POLITECNICO DI MILANO SCHOOL OF INDUSTRIAL AND … · Son olarak sevgili ailem, Annem Safiye’den...

POLITECNICO DI MILANO

SCHOOL OF INDUSTRIAL AND INFORMATION ENGINEERING Master of Science in Electrical Engineering Department

CHARGING INFRASTRUCTURES FOR ELECTRIC ROAD VEHICLES

Supervisor: Prof. Morris BRENNA

Author:

Semih SEVER

872135

Academic Year 2018-2019

iii

ABSTRACT

In the electric vehicle industry, one of the biggest challenges is to maintain the electric

power to the battery pack. Therefore, several methods used to charge vehicles.

Conventionally cable connects methods established since first invented battery electric

vehicle. These charging stations are supporting by different levels of electric power.

There are international standards with the purpose of to use these charging stations

across the globe by governmental and private institutions. As a consequence of this for

the different vehicle types, there are multiple options of plugs and connectors. Thus

accessibility of charging stations system getting ease in terms of technical and

financial. Furthermore, not only conventional charging stations under the use of

electric vehicle users, but there is also a system for wireless charging methods that can

charge the vehicle on parking position and on-road as well. The battery swap method

is also on the developing process to with some significant lacks on the system. This

thesis focus on charging stations with technical, financial and regional perspectives. By

the help of the local market analyzes of countries, it shows that why and how electric

vehicle industry get shape from past to future.

Keywords: Electric Vehicles, Charging Stations, DC Fast Chargers, Ultra-Fast

Chargers, Wireless Chargers, Battery Swapping

v

SOMMARIO

Una delle maggiori sfide è quella di mantenere l'energia elettrica per il pacco

batterie nell'industria dei veicoli elettrici. Pertanto, ci sono diversi metodi usati per

caricare i veicoli. Dal momento che il primo veicolo elettrico inventato ha stabilito i

metodi di connessione via cavo. Queste stazioni di ricarica sono supportate da diversi

livelli di energia elettrica. Esistono standard internazionali con lo scopo di utilizzare

queste stazioni di ricarica in tutto il mondo da parte di istituzioni governative e private.

Di conseguenza, per i diversi tipi di veicoli, esistono diverse opzioni di spine e

connettori. In questo modo l'accessibilità del sistema delle stazioni di ricarica sta

diventando più facile in termini tecnici e finanziari. Inoltre, non le uniche stazioni di

ricarica cablate sotto l'uso di utenti di veicoli elettrici, esiste anche un sistema per i

metodi di ricarica wireless che può caricare il veicolo in posizione di parcheggio e anche

su strada. Il metodo di sostituzione della batteria è anche in fase di sviluppo con alcune

carenze significative nel sistema. Questa tesi si concentra su stazioni di ricarica con

prospettive tecniche, finanziarie e regionali. Con l'aiuto delle analisi del mercato locale

dei paesi, mostra perché e come l'industria dei veicoli elettrici prende forma dal passato

al futuro.

Parole chiave: veicoli elettrici, stazioni di ricarica, caricabatterie veloci DC,

caricabatterie ultra veloci, caricabatterie wireless, cambio batteria

vii

ACKNOWLEDGMENTS

First of all, I would like to express my special thanks of gratitude to my advisor

Prof. Morris Brenna for his support, guidance, understanding, and encouragement

throughout my study and research.

I would also like to thank my tutors, In the last 2 years without their inspirational mini-

talks, well-proven knowledge, and high motivational support I would not have been

ready for my professional life in this field.

I would like to thank many of my friends and colleagues from Milan and Istanbul.

Especially, I owe special thanks to my friends, who are considered as a brother.

Mohit, Aroon, and Alberto. There was lots of trouble on my way in Milan, but you guys

always stand together next to me and encourage me to square things up. Thank you

guys for this amazing brotherhood. I know that I have a family in India, Spain, and

Pakistan.

I would not forget to remember Berke for his encouragement and moreover for his

timely support and guidance until the completion of our project work. We always

follow our dreams together, and we will continue to do it, my brother.

I would like to express my gratitude towards Alara and Betül. Girls, in the last 1 year we had lots of memories that I will never forget, but especially it is really significant to providing me with unfailing support and continuous encouragement throughout my years of study and through the process of researching and writing this thesis. This accomplishment would not have been possible without them. Thank you Son olarak sevgili ailem, Annem Safiye’den paylaşmanın, Babam Selim’den

dürüstlüğün, Ablam Begüm’den okumanın ne kadar kutsal bir şey olduğunu öğrendim.

Zor günleri sırtsırta verip aşılacağını bir kez daha Milan’da gördüm. Sizlere layık bir

evlat, kardeş, kayınbro ve torun olmak için her zaman hayallerimin peşinden

gittim.Bana olan inancınız , sabrınız ve sevginiz için sizlere teşekkür ederim.

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Contents

ABSTRACT ............................................................................... iii

SOMMARIO .............................................................................. v

ACKNOWLEDGMENTS ............................................................ vii

CHAPTER 1 - INTRODUCTION ................................................. 1

1.1 Motivation of the Thesis ............................................... 7

1.2 State of Art ........................................................................ 8

1.3 Goals of the Thesis ............................................................ 9

1.4 Structure of the Thesis .................................................... 10

Chapter 2- CHARGING STATIONS ......................................... 12

2.1 CONNECTOR TYPES ......................................................... 15

2.2 Charging Modes .............................................................. 19

2.2.1 Mode 1 ......................................................................... 22

2.2.2 Mode 2 ......................................................................... 24

2.2.3 Mode 3 ......................................................................... 26

2.2.4 Mode 4 ......................................................................... 28

2.2.5 Mode 4*1 ..................................................................... 31

2.3 Alternative Charging Systems ......................................... 36

2.3.1 Wireless Charging ........................................................ 36

2.3.2 Autonomous Battery Swap .......................................... 40

CHAPTER 3- CHARGING TIME ............................................... 44

3.1 Battery Types .................................................................. 44

3.1.1 Thermal condition of Battery and Environment .......... 45

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3.1.2 State of Charge value of Battery .................................. 48

3.2 Charging Characteristics ................................................. 49

3.3. Wireless Charging .......................................................... 54

Chapter 4 –COST ANALYSE OF CHARGING STATION AND

OPERATION .......................................................................... 58

4.1. The user side of Charging Cost ...................................... 58

4.2. Cost of Charging Techniques .......................................... 60

CHAPTER 5 - WORLDWIDE .................................................. 66

CHAPTER 6 – CONCLUSION .................................................. 74

xii

List of Figures

Figure 1 The first electric vehicle of Thomas Edison and BMW i3 2018 ................................................. 2

Figure 2 Tesla battery pack with car body............................................................................................... 4

Figure 3 a2a company DC charging station in Milan ............................................................................... 6

Figure 4 General Standards ..................................................................................................................... 7

Figure 5 PHEV vehicle illustration .......................................................................................................... 13

Figure 6 EV vehicle illustration .............................................................................................................. 14

Figure 7 Pantograph system .................................................................................................................. 17

Figure 8 Mode 1 connection type ......................................................................................................... 22

Figure 9 Electric system schematic of Mode1 ....................................................................................... 23

Figure 10 Mode 2 Connection type ....................................................................................................... 24

Figure 11 Electric system schematic of Mode 2 .................................................................................... 25




Figure 15 Tesla Supercharger ................................................................................................................ 29


Figure 17 Charge Mode 4*1 .................................................................................................................. 32

Figure 18 Siemens Ultrafast Charger and Substation............................................................................ 33

Figure 19 Ultra-Fast Charging stations for Large Scale EV .................................................................... 34

Figure 20 Electric Scheme of Ultra-fast charging station for Bus .......................................................... 35

Figure 21 Electric system illustration of Mode 4*1 for e-bus ............................................................... 35

Figure 22 Wireless charger for the house (Plugless,2019) .................................................................... 37

Figure 23 Electric schematic of wireless charger .................................................................................. 38

Figure 24 Two forms of Wireless Power Transfer ................................................................................. 39

Figure 25 Qualcomm Halo ..................................................................................................................... 40

Figure 26 Tesla Battery Swap ................................................................................................................ 41

Figure 27 Gogoro battery charging and swapping station .................................................................... 42

Figure 28 Charging characteristic in Thermal conditions ...................................................................... 47

Figure 29 Discharging characteristic in Thermal conditions ................................................................. 47

Figure 30 SOC levels .............................................................................................................................. 48

Figure 31 Constant Current and Constant Voltage .............................................................................. 50

Figure 32 Li-Ion battery charge profile .................................................................................................. 51

Figure 33 NiMH Battery charge profile ................................................................................................. 51

Figure 34 The efficiency of power transfer regard on the vertical gap ................................................ 55

Figure 35 Number of electric cars in circulation, 2013-2017 (in millions) ............................................ 66

Figure 36 Lithium-ion batteries placed on the global market (cell level, tonnes) ................................ 67

Figure 37 Charging Station Availability map.......................................................................................... 70

Figure 38 South Africa charging station map ....................................................................................... 71

Figure 39 Tesla Charger Map ................................................................................................................. 72

xiv

List of Tables

Table 1.Connector types........................................................................................................................ 16

Table 2. Important standards for EV ..................................................................................................... 18

Table 3. Charging Station Modes .......................................................................................................... 21

Table 4. Case information ..................................................................................................................... 46

Table 5. Charging time ........................................................................................................................... 53

Table 6. wireless charging duration ...................................................................................................... 56

Table 7.Case information on cost .......................................................................................................... 59

Table 8. Price list of charging station and accessories ......................................................................... 61

1

CHAPTER 1 - INTRODUCTION

Transportation tools and vehicles developed due to the needs of humans from

the first invention to the last one, the human brain tried to make it more efficient and

beneficiary to their life. After many developments in conventional vehicles around the

globe, Thomas Edison brought a good idea and he started to develop his first electric

vehicle with a developed battery system for the automobile market. Meanwhile, on the

other side of the Atlantic Ocean, Ferdinand Porsche created the world’s first hybrid car.

This brings that new brands and developments on automobile technology. Of course

on some years, the industry got huge drawbacks, especially during World War years,

automobile companies turn in to developed and produced more military vehicles,

which need more power on engine and fuel. Well-developed companies in Europe and

US started to continue their growing after 1945 and new kinds of vehicles take to roads.

Especially, high-speed engine systems of Ferrari SPA started production in 1947. These

kinds of situations increase the consumption of fossil fuels, and that’s why in the 1960s

there were huge crises happening about fuel prices all around the world. So as we can

understand from all issues about fossil fuels, the Automotive industry always needs

new developments. By the help of this mentality, NASA’s Lunar rover ran by electricity,

helping to raise the profile of electric vehicles. In this way, Electric Vehicles came into

our life more and more.

Governmental regulations about roads, electricity infrastructures,

manufacturing processes and etc. all started to shape considering to Electric Vehicles

and internal combustion engine-powered vehicles. More importantly, these facts made

way for new R&D projects in this field. A significant example of this, Tesla Motors,

which was a start-up company on field EV. Developing battery technology, motor

technology or material technology, all of them shed light on these kinds of projects in

this field. Meanwhile, in different countries battery charging systems and battery

systems got developed by scientific research groups. Finally, Electric vehicles started

to get find a place on the roads more day by day. Thus investments of the charging

infrastructures rise in the field of residential, commercial and public areas. According

to the European Commission, more than 100000 EV charging stations installed across

Europe till 2016. In a financial way, due to decreasing in costs of Battery systems car

on last years, Electric vehicles became more affordable for different customer groups.

But still, there will be lots of developments to achieve on different points in this field.

Especially, increasing of benefits of renewable systems to this system.

http://tureng.com/tr/turkce-ingilizce/internal%20combustion%20engine-powered%20vehicle

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Figure 1. The first electric vehicle of Thomas Edison and BMW i3 2018

In numerous cities across the world, personal vehicles are the single greatest polluter,

as emissions from millions of vehicles on the road add up. Vehicles working with a

combustion engine are rising up the pollution level in every kilometer that we drive

them. A regular personal car can emit about 4.5 metric tons of carbon dioxide per year,

and also regarding to production number of automobile companies, more than 70

million of a new vehicle is hitting the roads. By the help of this number of a pollutant

can understand much more easily. The effect of hazardous gases, which emitted by

vehicles with combustion engines, directly affects our globe and it has more trouble

with climate change year by year. On the other hand, governments have an agreement

on these subjects which is called the Paris climate agreement. This agreement

encourages to ban petrol and diesel engines from roads to decrease CO2 emission rates.

By the help of the Paris Climate Agreement, the sale number of diesel cars drop around

10 percent in the first year. With the new regulations in the EU, costumers are changing

their habits on this matter, and they tend towards hybrid and fully electric vehicles.

This new technological field plays a critical role on climate change issue.

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Fueling with electricity offers a good environment, especially EV has a zero-emission

rate because there is no combustion process on the system, even PHEV has a

significantly low level of emission than combustion engine vehicles. As a result of this,

utilization of EV, HEV or PHEV is one of the great solutions to decrease hazardous

gasses due to mobility. Adding to this, of course, it will increase electricity production

but the biggest advantage of it, it is not depending on the source. Most electricity

distributor companies try to supply this energy from renewable energy sources which

are more preferred one’s solar power, wind power, biomass. Thus, it will indirectly help

to the environment in a good way.

Furthermore, switching from fossil fuels to electricity will bring huge financial earning

to costumers. According to global petrol prices data in 2018, gasoline sold by 1,63€/lt

on average. Medium level family cars like Fiat Tipo contain a 45-liter gas tank, so every

refill the car will cost around 73,35 € to the costumer. However, on the same class for

Electric vehicle can be an example by Nissan Leaf fully electrical vehicle and customer

has to pay around 15€ per each full recharge and range of the car is around 320 km per

full charge. Thus electric vehicles will bring a good financial benefit to their owners on

using duration.

On the other hand, it has got some critical drawbacks. For instance, most of EVs have

short-range because of battery technology which is still developing day by day. Mostly

medium level EVs are limited to range 90 – 300 kilometers, but a small minority of

models can have reached 400 – 500 kilometers per charge. But of course the long-

range limit needs good technological development on the system of the vehicle, due to

the cost of vehicles getting high and it will cause to decrease in the accessibility of

costumers. Adding to this, a comparison of conventional vehicles and EV’S shows that

filling up the fuel of normal vehicles can take few minutes, but EVs’ recharging time is

not limiting by minutes, mostly it needs hours to recharge it. This is the result of the

technology of battery and charging stations, which will be told by this paper.

Technological developments on these components of EVs are improving together day

by day. These two subjects strictly depend on each other. And the story behind this is

a very long time ago.

As mentioned above electric vehicles were used in the early 1880s, thus the evolution

of the charging system, which includes a battery, charging station and power

converters, started on those days, the first rechargeable battery system which one is

also can usable on an electric vehicle is lead-acid. It invented by French physicist

Gaston Plante. Lead-acid batteries were cost-effective systems with high wave

currents. However, the lifecycle of this battery system was not well enough, when the

lifetime of a vehicle is really long. When Thomas Edison did investment in this field,

he aimed to build commercial automobiles with battery. On those electric vehicles,

charging stations were basic level power converters. Mostly they were settled on private

4

buildings to use. In the next 50 years, there were lots of investments happened, but

Lithium-Ion (Li-ion) and Nickel Metal Hydride (NiMH) were the most significant ones.

NiMH was more environmental battery system when compared with previous batteries

that invented. This battery type direct improved and supported by Daimler-Benz and

Volkswagen AG in 1989. They used Hydrogen-absorbing alloy as an anode, and Nickel

Hydroxide as a cathode. Most hybrid vehicles were used NiMH in those years, such as

Toyota Hybrid. Later on this system a technology company Sony released the first

commercial lithium-ion battery. Li-ion batteries have Graphite as an anode material,

and most often electrolyte type is salt suspended in an organic solvent. This system is

more flexible in the utilization part. Even that it can be used more effectively on

vehicles by changing cathode ingredients. In these years, Especially Tesla company

prefers to use the Lithium battery system, which is used in cathode side Lithium nickel

cobalt aluminum oxide (LiNiCoAlO2) cathodes, also known as NCAs. The biggest

advantage of Li-ion battery system can include more power with a high level of current

when compare with Lead-Acid or NimH.

Figure 2.Tesla battery pack with car body

5

Meanwhile, on the other side of the plug, basic charging stations started to be clever

devices to run this business in a profitable way. Distribution companies or vehicle

companies invested huge amounts of budgets in different levels of charging stations.

Especially regarding the utilization area of these vehicles show the way of investments

of charging stations. First of all, the main expectation was to increase the power

capacity of the individual charging station. Because every development of electric

vehicles needs to have a large capacity of the battery. The biggest disadvantage of

electric vehicles is the range of cars on one battery. Even although there is lots of

improvement in the battery management system, automobile companies are trying to

increase the capacity of batteries. Thus will bring a problem with long charging time.

That’s the way new improvements came at first by aimed to build a good capacity and

less charging time. In the meantime, a new development of smart grid systems on the

electricity industry brings the new concept to the charging stations, which is called

smart metering. Especially, this system works on convenience three subjects which are

billing, metering and safety of charging stations. Nowadays, these subjects are

important for better user experience as well as technical developments. The original

purpose of these new applications on charging stations, to build a new connection

between customers and companies. New mobile applications to get information about

the charging state or to have data to make billing in an easy way. Also, car share

companies are more intent to use this kind of services on charging stations. For

instance, Car2go and Drivenow companies do co-operation on the electric vehicle

category. They are using some kind of charging stations and they can encourage to use

electric vehicle services on their system instead of conventional ones. In addition to

that, when charging station companies do the billing, it’s free of charge to costumers,

even that if costumer will plug the car to the station when they are logged their account

on system, they are getting extra discount on their next trips. These kinds of

improvements on charging stations and battery systems are still in the process that will

shape by user experiences. Especially range and charging time problems are the main

aims for companies to solve them. Thus, there are different charging levels and types

in the field. At first, there were only AC outlets but now under the aim of fast charging,

there are DC charging systems.

6

Figure 3. a2a company DC charging station in Milan

Meanwhile, trustable Associations work to specify rules and regulations for the

systems on charging stations. International Electrotechnical Commission (IEC) trying

to work on Plugs, Socket-outlets, and Couplers for industrial and similar applications,

and for Electric Vehicles. They have got lots of projects to provide quality and safety.

Moreover, they are encouraging the countries to make an investment in this field for

research and development projects with the help of their committees in their member

countries. Besides IEEE is being at the fore on technical standards of Electric Sourced

transportation with the 2030 and 11-2000 standards. They are reaching to different

subjects under these standards as like as IEC standards. By the help of these standards,

different types of plugs like CHAdeMo or IEC 62196 Type 2 connectors are more

reachable with low costs with high quality. In another way to say this standard will

bring the getting to grow of the electric vehicle industry.

7

Figure 4. General Standards

In parallel with these developments and regulations, side industries of EV are getting

larger day by day. Plug producers, socket producers, high tech cable producers are

doing their research and developments. For different types of charging stations, there

are different solutions from these companies. SAE series sockets, CHAdeMo series

electric sockets producing by different companies from all over the world. But mostly

the production of charging station creates a giant industry in this field. According to

the needs of the industry they are bringing varied cost-effective power solutions.

However, all these developments are not necessary for every vehicle group, some of

them won’t bring any benefit. Thus, this thesis will bring the answer to which kind of

charging station will be better for a specific charging group and is it going to lead the

way of the electric vehicle industry in the next years.

1.1 Motivation of the Thesis

Electric Vehicle industry is on the developing process. There is much progress to

be made this technology more stable, cost-effective and environmentally friendly. On

the way to develop this industry, there are some critical parameters to achieve the

goals. Thus, usage of EVs, PHEVs or Hybrids will become widespread across the world.

8

The necessity of this thesis is to show the past and future of technological

developments in the EV industry by focusing on charging stations. Meanwhile,

compare the different charging levels regarding the technological background of

electric vehicles. Results will show that not the expensive product will give the best

solution to EV. Power level, area of utilization, battery type and this kind of parameters

will show what is the best charging station and what kind of technology it has got on

the behind. Moreover, the same type of charging stations can vary regarding to country.

Especially the percentage of renewables that feed the charging stations or safety

conditions of charging stations will bring different technological developments on the

same power level of charging stations.

1.2 State of Art

Once the main topics of this thesis have been concisely explained, the state of

the art of such technology is analyzed in this Section. Recent studies in this field

recharge operation of the vehicles focus on 3 different techniques as a problem solver,

which are cable type charging stations, wireless chargers, and battery swapping.

Researches and developments primarily focus on conventional charging stations. Thus

industry moves forward to this way. Scientific researches are running by both private

companies and universities. Developments on the side of private, public and

commercial transportation have needed different charging station solutions, regards

to power level and area of usage. Thus connector types and charging stations have

different types. Electric vehicle industry can get growing up in the globe more easily by

the help of the vehicles can interoperable with side service products, as like as charging

stations, and affordable access to this technology. Furthermore, emergent battery

technology keeps pace with the electric vehicle industry day by day. On the power

transfer side of the charging stations, first levels supply AC, and on the developed

model chargers started supply DC to the vehicle due to decline the charging time of the

battery pack. Besides high power, DC ultra-fast chargers are on developing a process

to maintain high power starting from mid-class electric vehicles to heavy-duty electric

vehicles as e-trucks, e-buses.

On the other side, wireless charges have great potential to solve the

disadvantages of the conventional cable type charging station. The wireless charging

method is just emerging technology. With the inductive and capacitive models of the

wireless chargers, currently, provide service to users on the park mode with a special

receiver pad which installs the vehicle later by private companies. But in the near

9

future, on-road charging models of the wireless chargers will be on the use of electric

vehicle drivers. According to yearly reports of the institutions, they believe that wireless

charger becomes widespread after the achievements of more efficient electricity

transfer by magnetic transfer system, default magnetic receiver on vehicles and

suitable electric network for this charging system.

Finally, the battery swapping system has a long story by big market players as

like Tesla. However, compared with other charging methods, the battery swap

technique has got more disadvantages due to that market players changed their scopes

on this field to 2 wheel electric vehicles and heavy-duty public transportation instead

of mid-class electric vehicles.

1.3 Goals of the Thesis

The main targets of this thesis are mostly two. In the first place, to develop a

proper categorization of charging stations regarding vehicle type. The most important

fact is to determine the power level of the vehicle at first. Regarding this, there are

requirements of these power levels that will directly affect range, charging time, cost of

the system. Thus there is a different variation of the trade-off between all parameters

according to the utilization type of EVs or PHEVs. Consequently, the first target is to

justify the way that how and why to use in the most correct utilization method of EVs.

Secondly, once the model has been properly verified and checked, the next

potential step is to analyze worldwide solutions about these systems. Regarding

customer habit and selection of EV on some main destinations in the globe. The

solutions for different countries or regions will show the perspectives and approaching

of those companies, due to that we can understand how the EV ındustry getting shape

in the same ways of the first part.

10

1.4 Structure of the Thesis

Chapter 2 introduces all variatıons of charging stations regarding the

international level class. There is a chart that combines all information about charging

levels. After all kinds of charging station levels are detailing step by step. On this part

there is no specific comparison, just detailed informing pros and cons about all

charging types. As technically there are also electrical power schemes of charging

stations, thus it is going to be more easy to understand the process on the system from

beginning till end. There is also an explanation of alternative charging stations, which

are wireless charging method and battery swapping technique.

Chapter 3 discusses the charging time of the charging stations. On the path to

explain the charging time, the main dependency will be power transformers and

battery profiles of vehicles. It is going to focus more on power electronic side of the

system. Furthermore, it is going to show how it will change the performance of battery

charging after long term usage of the vehicle for both charging time and discharging

time. Results support by the graphic on time domain.

Chapter 4 introduces the initial and operating costs of the charging stations.

Starting from infrastructural investment cost with technical aspects of all charging

stating, and if the power capacity of the system will increase or decrease how it will

affect to that initially. Furthermore, in the long term using time, what kind of

maintenance can be happening and fix costs for them. Lastly the customer side, how

much they have to pay to full recharge their vehicles.

Chapter 5 tells the world wide solutions about distribution and charging

stations. What kind of charging station is mostly used on the globe and future way of

EV charging station industry depends on EV type and selections.? Finally, significant

developments in this area regarding to green energy, user-friendly solutions or

technical developments from companies will be introduced.

Chapter 6 summarizes the main findings of this research and it includes a set of

recommendations for future work.

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Chapter 2- CHARGING STATIONS

EVs and PHEVs started to take place in the automobile industry day by day after

first innovations in that area. This system continues to the rising trend with the help of

the necessity to find a solution for fossil fuels. EVs and PHEVs are started to preferred

in these years by costumers. Under the details of those two vehicle types, systems are

different a lot.

PHEV is a hybrid vehicle that has an internal combustion engine and electric

engine at the same system. The biggest difference between PHEV and HEV is users can

charge the battery of the car from external energy sources via charging stations. These

vehicles’ system is depending on the RPM level of the engine. On the high RPM levels

IC engine working for high performance, but on low rpm levels as such as 1000-3000

RPMs electric motor is working directly energized by batteries. Another way of the

working system of PHEV is vehicle initially works with an electric motor and when the

battery gets close to cut off level, the internal combustion engine starts to work. The

energy of PHEV also supported by the braking system, the regenerative braking

method converts some of the energy lost during the breaking into useful energy. PHEV

has got different transmission systems, it can be series, parallel or series-parallel. Thus

the complexity of the electrical system part will change regarding -working type of ICE

and electric Engine. One of the parallel configurations is illustrating in the picture

below. Adding to that, as a power system it has got on-board charger system, which

takes incoming electricity supplied by charging station in AC current. This on-board

charger works as AC/DC converter. Also one of the main duties is monitoring the

battery statutes with parameters of voltage, current, temperature or state of charge

during the charging time. Also, there is an individual DC/DC converter to convert

supplied electricity from regenerative braking system to battery pack. With the help of

the power electronics controller, all these power unit operating in efficient way in a

bidirectional.

13

Figure 5.PHEV vehicle illustration

On the other side, EV works with an electric traction motor with feed by the battery

pack. From the initial starting of the motor to the final stop, all processes working by

one or more electric motor and battery systems. That’s why the battery pack is much

bigger than PHEV which means that power needs, charging time and this kind of

parameter are different than other systems. In the picture below, there is an illustration

of the basic system of electric vehicles. On the side of the power unit, there is a charge

port, on-board chargers are the main components to energize the battery pack. There

is also a second auxiliary battery that provides electricity to vehicle accessories such as

an entertainment system. This battery connects to DC/DC converter which is directly

connected to the on-board charger. This on-board charger works as AC/DC converter.

Also one of the main duties is monitoring the battery statutes with parameters of

voltage, current, temperature or state of charge during the charging time. In the

illustration vehicle is a medium scale electric car, for larger or small scale vehicle types

system, is mostly the same but the size of the motors or battery pack change regarding

power necessity of vehicle.

14

Figure 6.EV vehicle illustration

These two types of vehicle common necessities are charging. There are several charging

types according to vehicle type. According to customers ' facilities that they have, these

charging stations can be changed. For instance, the basic version of charging station is

the residential type which can be feed by household power inlet 220-volt Ac. It’s a basic

system, on the same cable it contains a transformer, connector which plugs into

vehicles, and other connectors fit the basic power inlet which feeds 220 Volt AC. This

is more personal usage and this system named Level 1 charging stations. There can be

different connector types on this system according to the brand of vehicle and also

socket type can be changed regarding to country.

Another way to charge the electric vehicle is charging pools. These charging pools

mostly operate by private companies, and each charging pool can be found on common

areas inside of the city, universities, shopping malls, workplaces, airports and etc. and

also can be found on highways as well. In another way to say that charging pools are

parking lots to charge electric vehicles. Thus it contains one or more electric vehicle

charging stations, which is an essential device that charge vehicle charging stations can

15

be equipped with RFID Reader, buttons, displays and LEDs to make the process much

easy for users. Or it can be plug and charge type of station without any tool. On the

system of charging stations for power delivery, there is a charging point and

connectors. Charging points are electric vehicle supply equipment. This tool plug part

of the system. Electricity feed by this socket. It may have several types of connectors.

Because for every level of charging station, the connector type can show a change.

Connector work as an interconnection cable between vehicle and charging point. As a

type of connector cable system, there are four main types of connectors.

-A plug on cable that each side of cable ahead has one female or one male version. One

side of the cable plug into charging point of the charging station, the other one plug

into the energy inlet of the vehicle.

- A fixed cable directly coming out from the charging point and its inseparable, other

side of the cable has a connector and it plugs into energy inlet of vehicle.

- Pantograph system is mostly used on the utilization of buses, trucks or minivans. A

practical way to recharge the vehicles on the road stops or in their parking slots. Also,

the Pantograph system is a good way to deliver a large amount of energy from charging

station to vehicle.

-Induction plate last type of connection system. This is not a common method to charge

vehicles, but for the future, it will. On the basic energy delivered via inductors, one

under the ground, one under the vehicle. When the vehicle stops at the top of the

charging lot, electricity delivered by the rule of electromagnetic energy delivery.

In general, number of charging points and number of the connector is the same on

charging spots, however, some multiuse charging stations can serve different

connector types, however from all charging points can be charged only one car at the

same time.

2.1 CONNECTOR TYPES

Connector types divided into 5 different models. These models featured

according to the charging system of the vehicle. Thus all vehicle brands use different

models of the connector, according to their vehicles’ technical features. As a brief type

of connectors can bee see on the table.

16

Type of connector Connector & Vehicle Inlet

TYPE 1

SAE J1772 , IEC 62196-1

Type 2

IEC 62196-2

Combined Charging System

CCS Combo 2

Type 4

CHAdeMO

Tesla Supercharger

Table 1.Connector types

17

Type 1; its standard model for AC charging systems which design in Japan. For the

models are SAE J 1722 and IEC 62196-1. It designed for single-phase electricity with

120 V or 240 V. It has got 5 pins for Ac line, Ground, proximity detection, Control Pilot.

Useable for charging levels 1 and 2. A few popular cars that use this Nissan Leaf,

Peugeot ion, Ford focus electric, Toyota Prius plug-in.

Type 2; this type of connector approved by the commission of the European Union for

the standards of electrical vehicles. it is designed for single or three-phase electricity

with voltage range 250 – 400 V. It includes 7 pins for Ac line, Neutral, Proximity

detection, Control Pilot, Connection Confirmation. Useable for charging levels 1 and 2.

Some of the popular vehicles that used to charge with type 2, BMW I3, i8, Audi A3 E-

Tron, Volvo V-60 PHEV, Renault Kangoo ZE.

Combined Charging System; developed version of type 2, which included fast charging

by additional pins. The system is designed for DC system with a voltage range of 200

– 500 V. Additionally to type 2 it has got 2 more pins for DC inlet. This connector can

be used for charging level 3. Some of the European automobile companies selecting

these connector types, for example, Audi, BMW, Porsche, Volkswagen.

Type 4; this connector designed to use in DC electricity with a voltage range 250 -400

V. It has ten pins with two different pin diameters. These pins are for ground for

insulation, control EV relay, N/A, ready to change control, power line negative, power

line positive, proximity detection, communication positive, communication negative,

Control EV relay 2. This connector can be used on charging level 3. Some of the popular

vehicles that used to charge with type 4, Nissan Leaf, Nissan E-NV200, Citroen C-Zero,

and Kia Soul.

Tesla Supercharge is designed specially for Tesla

vehicles. It designed for single/three-phase electrical

systems with voltage range 110 VAC or 480 VDC. This

connector has got five pins in total. These are AC line 1,

AC line 2, Neutral, Proximity Detection, Control Plot,

Connection conformation. This connector can be used on

charging levels 1 and 3.

In addition to these connector types, a Pantograph is also

one of the styles of connectors. The purpose of this

system is to charge heavy vehicles such as buses, trucks.

It is a great solution for public transportation. It’s

designed like CCS, so it works for the DC system with a

high capacity for power delivery. Figure 7.Pantograph system

18

On the standardization of connectors to work on all brands of electric vehicles,

institutions regulate them via international standards for safety and quality, charge

connection, communications, and charging system. Standardization organizations are

setting a baseline on the EV charging industry with the help of these regulations. One

of the significant examples is IEC, which is the leading organization on

standardization, has standards with code of IEC 62196-1 /-2 /-3 to maintain the

standards of plugs and sockets on electric vehicles charging stations. These kinds of

regulations take manufacturers to the common standards, that’s the way Electric

vehicle system can be international. In another way to say that, on the same connector

type there will be no difference in US or European systems. Furthermore, another

benefit of these regulations to specify the safety and quality of products. Starting from

grid to electric traction engine minimum safety and quality levels fixed by IEC and ISO.

Insufficient products and companies are getting a ban from the system. On the below

table, different standards can be seen for the EV charging system. These regulations

get expand year by year to achieve a more efficient EV industry.

Category Standards

Safety and quality

IEC 60529

IEC 62262

EN 50160

IEC 61140

IEC 61000-X

IEC 60364-X

ISO-6469-3

Draft ISO/IEC 17409

Charge connection

IEC 62196-1

IEC 62196-2

IEC 62196-3

Communication

IEC 61851-24

IEC 61851-X

ISO/IEC 15118-X

Charging system IEC 61851-1,21,22,23

IEC 61439-7

Table 2. Important standards for EV

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2.2 Charging Modes

For the different power levels, there are several charging modes for electric

vehicles. As mentioned in the below table there are four main modes of charging

stations regarding European standards. The main parameters to divide into groups of

these charging modes are the current type, and power levels. Thus to describe all

parameters;

-Charge speed; charging stations category according to charging duration. This can be

slow or fast as a parameter, but to more specific categorization charging time must be

checked to understand the speed of charging.

-Current type; this can be AC or Dc.

- Phase; On the grid side regarding the charging level, it shows power type to the reader.

-Voltage; to understand the electrical potential difference. It can vary from 0- 1000

Volt. This is the first variable to find the power of the charging station.

-Current; on the basic, it is mention that the flow of electrons per second. It can vary

from 0- 500 Ampere. This is the second variable to find the power of the charging

station.

-Useful power; to find transferred electrical energy by the formulation of Power =

Current*Voltage. It can vary from 0- 200 Kilowatt. This is the main parameter to

specify the category of the charging station. Useful power is the nominal value of power

that fed by the charging station.

-Maximum power output; max power available power on that charging station.

-Charging time; respect to selected vehicle type ‘s battery capacity and power inlet of

charging station, average time duration to full fill the battery.

-Connector; regarding input charging current and type, selected connector type that

mentioned previously in this chapter

-Communication; regarding connector type, if there is any communication between

vehicle and charging station, this parameter can be yes or no and specified in one

direction or bidirectional.

20

-Area of use; mostly selected area to use of these charging stations. It can be residential,

public or commercial.

21

MODES MODE 1 MODE 2 MODE 3 MODE 4 MODE 4*1

CHARGE SPEED Slow Slow Slow/Fast Fast Ultra-Fast

CURRENT TYPE

(OUTPUT)

AC AC AC DC DC

PHASE

(INPUT)

Single-phase Single-

phase/Three-

phase

Single-

phase/Three

-phase

Three Phase Three Phase

VOLTAGE

(OUTPUT)

120 V 240 V 240 V-480 V 200-450 V 1000 V

CURRENT

(OUTPUT)

15-20 A 15-20 A 40-120 A 80-200 ADC 500 ADC

USEFUL POWER

OUTPUT [KW]

1.4 3,7 7.2 50 350

MAXIMUM POWER

OUTPUT [KW]

1.9 22 >22 150 500

CHARGER On-board On-board On-board Off-board Off-board

CHARGING TIME

[HOURS]

7-17 6-13 3-7 0,5-1,5 0,2-2

CONNECTOR SAE J1772 SAE J1772 SAE J1772 SAE J 1772 Combo,

CHAdeMO and

Supercharger

CCS Combo,

CHAdeMO and

Pantograph

COMMUNICATION No Yes Yes Yes Yes

AREA OF USE Residential Residential/Co

mmercial

Commercial Residential /

Commercial

Commercial/Public

transportation

Table 3. Charging Station Modes

22

2.2.1 Mode 1

This one is the basic level of charging stations. It directly energized single-phase

AC current via regular household socket (NEMA 5-15) with 120 V and around 16 A

with the standard. Mode 1 can charge less than 2 kW per hour. The connection

provided by type connector, one side is directly plugged of the NEMA other side of the

cable is SAE J 1772, due to that there is no initial cost except charging cable. On the

side of the charged vehicle connector, connects to the onboard charger which

component works as AC/DC converter. Adding to that, it is work for monitoring the

battery statutes with parameters of voltage, current, temperature or state of charge

during the charging time. This model is not a preferred charging model in European

countries. However, in the US market, it is still a choice of selection. If we exemplify

with a real electric vehicle, such as Nissan Leaf 24kWh edition, car will get a full charge

in 15 hours. Thus mode 1 is a slow charging method. Another disadvantage of this mode

is there is no communication system between cars and socket. Adding to that there no

additional electrify safety system on this system. As it is seen from these lacks of

system, it is more feasible to use at residences.

Figure 8 .Mode 1 connection type

23

Charging mode 1 does not require any special system as an electrical infrastructure.

Users can directly connect their vehicle to plug and supply 120 Volt with 16 A via

household socket. As seen in the below figure on the behind of the socket there are only

three electrical components for only safety. As a safety rule of charging station, voltage

cannot exceed 120 Volt for US (250 Volt for EU), and charging current can must to

limited on 16 A or 480 Volt – 16 A in case of three-phase AC. Thus from the power

supplier of the house/apartment, there has to be a circuit breaker to prevent overload

faults. For the safety rules, it’s recommended to put surge arrester to prevent

overvoltage. Thus it is feasible to use this simple design to charge the vehicle as an

electrical infrastructure, which is the elements;

1-Residual current operated circuit breaker,

2-Surge arrester

3-Circuit breaker

Figure 9.Electric system schematic of Mode1

24

2.2.2 Mode 2

Mode 2 charging is a bit developed model of mode 1. It directly energized single-

phase AC current via regular household socket with 240 V and around 16 A with a

standard. Adding to that three-phase 480 V can be also used with a standard socket.

There is an opportunity to do AC charge at any household socket, in European

Countries F type is using as a standard. Mode 2 can charge around 4 kWh. The

connection provides via cable with the controller. This communication is providing via

PWM communication. Socket part is again a male version of F type and another side

of the cable is SAE J 1772 or IEC 62196-1. In the middle of the cable, there is a controller

that provides electrical stability and safety and also communication as well. On the side

of the charged vehicle connector, connects to the onboard charger which component

works as AC/DC converter. Adding to that, it is work for monitoring the battery statutes

with parameters of voltage, current, temperature or state of charge during the charging

time. If we exemplify with a real electric vehicle, such as Nissan Leaf 24kWh edition,

car will get a full charge in 7 hours. Thus mode 2 is also a slow charging method. The

mode 2 charging option can be used in residential. For the night charge, it can be basic

but safest option to charge. However, it is not a good way to drive through a charging

option.

Figure 10. Mode 2 Connection type

25

Charging mode 2 does not require any special system as electrical infrastructure. Users

can directly connect their vehicle to plug and supply 120 Volt with 16 A via a household

socket. As seen in the below figure on the behind of the socket there are only three

electrical components for only safety. As a safety rule of charging station, voltage

cannot exceed 250 Volt for EU, and charging current can must to limited on 32 A or

480 Volt – 32 A in case of three-phase AC. Thus from the power supplier of the house

or apartment, there has to be a circuit breaker to prevent overload faults. For the safety

rules, it’s recommended to put surge arrester to prevent overvoltage. In this mode,

there has to be in cable control box(ICCB) in which product supply communication

between car and charging port. ICCB is coming with charging cable. Thus it is feasible

to use this simple design to charge the vehicle as electrical infrastructure. On this

system electrical components are;

1-Residual current operated circuit breaker,

2-Surge arrester

3-Circuit breaker

4- ICCB

Figure 11.Electric system schematic of Mode 2

26

2.2.3 Mode 3

The latest version of the AC charging mode is mode 3. On the electricity feeder

part, there is a wall box or individual charging station. Charging cable is separately

from the charger again, but on both sides of the cable, there is Type 1 or Type 2 style

multi-pin connector. This charger type is working with 250 V with 32 A single-phase

AC current or it can be also use as a three-phase current with 480 V and current can be

reached to 70 A. Mode 3 can charge more than 22 kWh. On the type of mode 3 type

charging stations, electrical protection and safety devices are inside of the charging

module. PWM communication system also inside of the charging station. On the side

of the charged vehicle connector, connects to the onboard charger which component

works as AC/DC converter. Adding to that, it is work for monitoring the battery statutes

with parameters of voltage, current, temperature or state of charge during the charging

time. This is system is one of the most preferred models in charging pools and

residential use. If we exemplify with a real electric vehicle, such as Nissan Leaf 24kWh

edition, car will get a full charge in 4 hours. This system is a more preferred option to

charge the car by automobile companies. Because number of installed charging

stations in countries. Also, Battery systems are available to this model.

Figure 12. Mode 3 Connection type

27

In opposition to mode 2, this charging mode does not have restrictions for the current

and voltage supply of AC power. The charging stations can connect to a single-phase

or three-phase AC grid and this can manage by charge control box which

instantaneously communicates with onboard charger and charge controller in the

charging station. The charging station of mode 3 needs to protect from the line-side

residual current by circuit breaker and overcurrent protection device. For the safety

rules, it’s recommended to put surge arrester to prevent overvoltage.

1-Measuring Device

2-Surge arrester

3- Residual current operated circuit breaker

4-Circuit breaker

5-Contactor

6-Charging controller


28

2.2.4 Mode 4

At the end of the first decade of the 2000s, the CHAdeMO connector system was

invented by a Japanese company. The main purpose was to convert the charging power

from AC to DC. With the help of this charging time and lifetime circle of the battery

would be much better. Finally, just in Japan, they set around 600 CHAdeMO DC fast-

charging stations which are operated by Type 4 connectors. This system is supply DC

current from charging station to vehicle. Supply power feeds up to 500 Volt and input

current is changing proportional but mainly 80 ADC. Mode–4 is the first level of Dc

charging station. It can charge up to 150 kWh. From the power grid side supply itself,

AC current with three-phase with 480 V. Similarity between mode 3 charging stations

and DC type charging station is electrical protection and safety devices are inside of the

charging module. PWM communication system also inside the charging station.

However, instead of an on-board charger, there is an off-board charger system inside

of the charging station. Thus vehicle energizes directly by DC current. Connection of

charging station and vehicle is direct with a cable and as a connector plug, there is

mostly use type 4 connectors. If we exemplify with a real electric vehicle, such as Nissan

Leaf 24kWh edition, car will get full charge in 30 minutes. After all these technical

benefits CHAdeMO has the largest charging station service in globe. Instead of

residential use, this system installed more commercially. That’s why on the highways

or in urban areas of city there are lots of Mode-3 charging stations.

Figure 14 . Mode 4 Connection type

29

Furthermore, there is also an efficient version of the DC charging station developed by

Tesla company. This charging station type named Tesla Supercharger. Tesla

supercharger has integrated specifically for Tesla vehicles. As a technically significant

benefit of Tesla Supercharger is, charging rate power is 150 kWh with 480 V DC and

250 A. Tesla Supercharger can recharge the battery in 1 hour when compared with

regular DC chargers. Adding to that cooling system of superchargers is based on liquid-

cooled cable instead of a regular fan system. On the system of Tesla Supercharger CCS

type connector is using.

Mode 4 charging station is a much more developed system when compared with the

first three. In the following figure, a proper DC charging station is illustrating. The IEC

61851-1 standard recommends further options on using of AC connection. In this

mode, there has to be a control system between the vehicle and the charging station.

However, regarding standard connection cable need to permanently connect to the

charging station.

Starting from the AC grid side to the DC side, the main supply of power will be three-

phase Ac. This electric flow will pass through a measuring device to control the billing

system. This mode requires a line side AC/DC sensitive residual current operated

Figure 15 .Tesla Supercharger

30

circuit breaker and overcurrent protection device for both AC and DC. As seen in figure

16, this charging station has own AC/DC converter. This brings the opportunity to

bypass the on-board charger in-vehicle, if it has, and charge the battery faster than the

first 3 modes.

Regarding the IEC 61851-1 standard, this system can supply up to 1000-volt AC and

1500-volt dc. Adding to that regarding standard IEC 69/206/CDV2011. Due to

standard, there are lots of things to control this charging station mode. Under the

restrictions and regulation of these standards, this electrical system must check or

control these points in operation. The control box needs to check if coupler of the

vehicle is switched off, due to the user can plug or unplug the connector. This can be

done by mechanical or electronic systems. This communication needs to check by the

bidirectional communication system of the charging station. Thus it has to check, is

connection properly done or no. Checking of bonding and protective earth conductor.

System on /off switching. Instantly measurement of current and voltage on the system.

Blocking, locking and releasing the vehicle coupler with mechanical or electronic

system. Protection of charging device and battery from overvoltage or overcurrent.

Voltage check of the charge leads prior to unlocking the vehicle coupler. Short-circuit

check between +and – of DDC circuit output prior to charging. The user-triggered

off-switching of the charging current. Overload protection for parallel conductors. To

sustain all requirements of fault protection.

1-Measuring device

2-Surge arrester

3-AC/DC Sensitive residual current operated circuit breaker

4-Circuit breaker

5-AC/DC Converter and fuse

6- Insulation monitoring device

7-Cırcuıt breaker

8- Surge arrester DC

31

2.2.5 Mode 4*1

The high power charging option on DC charging stations is ultra-fast DC

charging station. It can charge up to 450 kW with the latest improvements. The system

is feeding by nominal 3 phase AC current with 480 Volt and the nominal input current

is around 248 A. Later on the conversion of AC to DC current output values are

maximum voltage 1000 V and maximum current up to 500 A. Ultra-fast charging can

charge up to 450 kW. This system generally consists of 2 parts. The first part is the

power unit, which includes the AC-DC converter and the electrical control system. The

second part is user interface and charger ports that inseparable cable with CCS

connector. Regarding the power level of the charging station power unit of the system

can get larger. Thus, e- bus or e-trucks can be charge more efficiently. Adding to that,

on the second side of the system, connection type can be preferable as a mechanical,

which mentioned above as a pantograph. Compared to other charging systems this one

needs more power than others. Instead of the traditional cooling fan system, it has got

liquid cooling system on power converter side and delivery side. On the behind of the

design concept, dielectric cooling liquid flow from the cables throughout connector’s

contact system which part is releasing heat more. This dielectric liquid is safe for

environment and also the weight of the cables is optimized and a small cable diameter

gives a flexible and easy to use working condition.


32

There are a few different scenarios for the ultra-fast charger. Regarding the power

necessity of the vehicle, the system can be more compact nor complicated. On the basic

level of the ultra-fast charging station, there are one body chargers which include

power unit and charging console. These charging stations can charge up with 175 A

maximum. Thus it is more efficient for small scale EVs. If we exemplify with a real

electric vehicle, such as Nissan Leaf 24kWh edition, the car will get a full charge in 30

minutes. In this type of charging station of ultrafast DC, users can use CCS or

CHAdeMo charging connectors.

“

Secondly, new full-electric models of Porsche and BMW adapted to this system which

project developed by Siemens. It is consisting of two-part, at first part power unit with

a high level of charging capacity and the second part is charging console which includes

a monitor and inseparable connector. This charger can charge up 350 kW and it aims

that it will charge these high capacity batteries less than 1 hour.

Figure 17.Charge Mode 4*1

33

Figure 18.Siemens Ultrafast Charger and Substation

Finally, one of the latest models and still it’s on the process to develop by different

companies. This system is a more complex model for public transportation and is

divided into 3 systems. The first one is especially for buses, high powered ultrafast

chargers which installed to stations can get connect to buses or trucks for 20 seconds

by pantograph and it can charge it around 20 kW and till the next station vehicle will

consume it. Thus it makes a charging cycle starting from the first station to the last

station. On the second step, the same charging station set it on main stations or stops

which can be also named as waiting area. On this stop vehicle generally, wait around

6-8 minutes and charging power can vary 150/300/450 kW. The final charging option

is plug based version, for the long duration charging this system can charge in 2 hours

with off-board DC charging system. This type of power unit consists of 1 or more high

capacity converters regarding the necessity of power level, thus it can charge up to 1000

V with a maximum 500 A. This system needs high investment initially. Because it needs

an individual transformer system that makes a connection between the grid and power

unit and also for the transportation web it needs station chargers with a pantograph

system. For the use of public transportation, it’s still on improving the process.

However, there are few ring systems work in service around the globe, which are in

Hamburg Germany by Siemens, Stockholm Sweden by Sıemens and Switzerland by

ABB.

34

On the fast-charging station, it’s a more developed system when compared with DC

fast charger. On the grid side, there is 3 phase AC electric supply up to 400 Volt with

250 A for the small size electric vehicles. This type of charging station generally

combines with an independent substation next to the charging station. This charging

station mode has to follow the regulations of IEC 61851-1 as well as mode 4. Thus the

same operational controls are the same for this station system. Adding to that, there is

one important point for ultra-fast chargers. On the charging process, the Temperature

of the cable system of the charging station will get high, due to that, there is a special

liquid-cooled cable system working on the charging station. This cooling system

having circulation inside of the charging station and it acts like heatsink on charging

cable and connector. With the help of this system, on the output side, it is possible to

transfer 500 A DC through the vehicle without any loose on efficiency. In the next

chapter, there will be an explanation of effect of thermal condition for battery and

charging station.

The heavy-duty vehicle system needs to have a more powerful charging station and

substation. On the input stage, ınstead of normal DC fast chargers, this system has a

DC/DC boost converter to supply up to 1500 Volt DC. Adding to that on the electric

transfer side from the charging station to the bus, there is a pantograph system that is

also equipped liquid cable system. The beneficiary side of the pantograph is universal

design. It means that these charging stations can charge all different model electric

busses or trucks equipped with the coupler of the pantograph.

Figure 19.Ultra-Fast Charging stations for Large Scale EV

35

Figure 21.Electric system illustration of Mode 4*1 for e-bus

Figure 20.Electric Scheme of Ultra-fast charging station for Bus

36

2.3 Alternative Charging Systems

The alternative of plug charging method, there are also two more charging

techniques which are an emerging technology. These are battery swapping and

inductive wireless charging for electric vehicles. These two technology responds to the

need of the main disadvantages of the plug charging station. Wireless charging method

will solve the safety problems due to old or damaged cables and also extra workforce

to plug/unplugged the cable for the user and extra to that with the new technology of

smart electrified roads, electric vehicles can chargeable while driving. On the other

side, battery swap technology can problem solver of one of the biggest problems of

traditional charging methods.

2.3.1 Wireless Charging

The wireless charging system is one of the hope-inspiring charging technique

for the future of the EV industry. This developing technology can analyze under two-

part, first parking slot charging, second driving charging.

On the parking condition, the wireless charging system is actually really compact and

based on a simple design. Under the regulation standards of IEC 61980-1, it provides

a secure and efficient system. Starting from the components, this charging station

power supply varies household power to a high voltage power supply system. That’s

why it can categorize into 3 types.

Household Wireless charger

This charger is equal to traditional charging station mode 2. The system is based

on three components as seen in figure 21, which are the control box, parking pad, and

vehicle pad. The control box directly connects with household socket, F type for the

European system. Thus it supplies energy 240 Volt Ac up to 32 A. Theoretical charging

37

power outlet is 7,2 kW continuously. This model of wireless charging stations is easy

to install in private areas. If EV doesn’t have own vehicle pad as a receiver, there is

mountable ready to use vehicle adapters. These adapters are directly connecting with

the onboard charger to be part of the charging system of the car. System work is really

simple after the connection of the charging station. The driver needs to park the car

just on the top of the parking pad. After all, charging will start immediately. If we

exemplify with a real electric vehicle, such as Nissan Leaf 24kWh edition, car will get a

full charge in 6- 8 hours.

Figure 22.Wireless charger for the house (Plugless,2019)

On the technical side of this system, the diagram of the wireless charging station can

see in below figure 22. The wireless charger has got two different models regarding to

power transfer types, one is capacitive power transfer and another one is inductive

power transfer. Inductive power transfer (IPT) using coils that are coupled through

magnetic fields, and capacitive power transfer (CPT) using plates coupled through

electric fields. As mention above, the system is feeding by the AC source. AC source

values depend on charge power output. Entered electric passes through the rectifier,

due to the purpose of having high frequency alternated current before primer coil. After

38

that magnetic field will arise on primer coil and magnetic energy transfer to the

receiver coil which is a part of the vehicle. With the help of the receiver coil, magnetic

energy will turn in to AC electric. If the vehicle has got own onboard charger this coil

can directly connect with onboard charger, otherwise, there has to be AC/DC converter

to charge up the battery.

As mentioned in the above, this system can work with different charging power outlets.

Not only small size electric vehicles, but it can also perfectly work on heavy-duty

charging stations. According to the power need of the vehicle’s battery system, the

charging station needs to potentiate.

Figure 23. Electric schematic of the wireless charger

On-road wireless charging technique, the system needs bigger technical infrastructure.

Under the idea of charging the vehicle, while driving process, it is one of the biggest

problem solvers of the EV industry. The working procedure of the on-road wireless

charging is so basic. The track system has to install under the road. In some periods of

meters, there has to be a capacitor for the continuity of power, and also there have to

39

be power supply points to feed the system properly. In the below figure 23. It can see

two different forms of on-road wireless charging systems which are, (a) CPT, (b) RIPT.

The main difference between these two forms is; transmitters are different in each

other. On the first one system is based capacitive power transfer. In the second one,

the power transfer system is different. It has got a coil system which divided into equal

lengths of pad. Consist of a series array of these pads gives a chance to charge the

vehicle continuously as well.

Figure 24.Two forms of Wireless Power Transfer

Qualcomm company is working on the field of this project to make this dream real. As

seen in the picture, on the test track there are four 25 meter stubs each of them has its

own power supply, and each stub powers 14 base array network blocks couples

magnetically into backbone cable. Power transmitted across the air gap to two 10 kW

vehicle pad underneath the EV. The onboard charger of the EV converts 85 kHz AC

and delivers to the battery pack as DC power.

40

Figure 25.Qualcomm Halo

2.3.2 Autonomous Battery Swap

The second Alternative charging technique of the traditional charging station is

an autonomous battery swap. The answer to the question the range and the charging

time problem. The system based on the behavior of a gasoline station. Low charge

battery vehicle comes to Autonomous Battery Swap Station (ABSS) and just under the

90-second operation is done. No need for a workforce of anybody, all systems just

serving the service autonomously.

In 2013, Tesla company present their Autonomous Battery Swap system for Tesla S

vehicle and to prove the quickness of the system they introduce a live challenge with

Tesla S and one ICE vehicle. Result of the challenge Tesla S swapped the battery and

been fully charge condition 2 times faster than an ICE vehicle. However, the next year,

Tesla company cancel the battery swap program because their costumer shows no

interest.

So how was the system’s operation, EV need to come to ABSS and need to stay on the

top of the automation parking system. After that, the swapping process works step by

step underneath the vehicle. At first low Battery taken by the system and on the second

step new fully charged battery plugging into vehicle and customer leaves the station

after this. An old battery stored inside of the station, it would charge on that station or

company would collect old batteries to charge up in a big facility.

41

Figure 26. Tesla Battery Swap

Unfortunately, this charging method doesn’t on the way of developing because of

disadvantages on technical and financial subjects. However, local e-motorcycle

companies are highly interested in this. Taiwanese company Gogoro is one of the

companies that is working in this field. Their aim is to build a battery swapping system

on their smart scooter web, thus user’s will swap their batteries instead of charging

them in the parking slots. In figure 26, the battery swapping station can serve 20

motorcycles at the same time. Meanwhile, the old batteries can charge up while waiting

time for the next customer.

42

Figure 27. Gogoro battery charging and swapping station

44

CHAPTER 3- CHARGING TIME

Charging time is one of the major challenges on EV charging. Starting from the

charging station to the battery there are few parameters that affect the

charging/discharging duration of EV. To understand the charging time on EV, the first

battery systems need to be understood.

3.1 Battery Types

The battery pack was one of the main trouble spots on this subject. As a basic

terminology, the battery is a closed system which occurs chemical reaction between

electrochemical cells with external connections. The flow of electrons between anode

and cathode provide power to the system by passing through electrolyte. At the

beginning of the story, batteries are started to use in the automobile industry for initial

energy or lighting with a lead-acid battery. Lead-acid batteries started to take a place

as an energy source to traction engines by reason of the low cost and maturity of the

technology and high availability on the market. On the technical side, it has got lead

dioxide (PbO2) as a cathode and lead (Pb) as an anode. The system can deliver very

high current and also internal impedance is low. However, the efficiency of the battery

is about 70%. The typical cycle life is 300 to 500 cycles, so it means that battery life is

no longer than the vehicle. Another disadvantage is it doesn’t have a compact structure,

thus for a large amount of power capacity it needs to occupy larger space and it will be

heavy. As an environmentalist view, lead has hazardous effects on the earth. On the

charging condition or regarding the temperature of the working area there is a danger

of exploding of battery because of overheating.

Secondly Nickel-metal- hydride batteries are preferred on EV by companies. This

battery comes with high energy density and it can charge up to 3000 time which is

much longer lifetime than the lead-acid battery and adding to that it’s possible to the

user on a fast charge. One of the best advantages of the NiMH is it has got a flat

discharge profile at the end of the cycle it falls rapidly. However, on the charging state,

it can rapidly charge. As an electrochemical side of the battery, it uses nickel hydroxide

as a cathode, an anode of Hydrogen absorbing alloys and there is Potassium-Hydroxide

(KOH) as an electrolyte. Absence of Cadmium, Mercury or Lead will bring this battery

as environmentally friendly. The main problem of NimH is poor efficiency especially

in cold weather condition and also it has got a high potential for self-discharge.

45

Thirdly, Sodium Nickel Chloride (NaNiCl) type batteries usable on EV. This battery

type is suitable for large capacity which is more than 20 KWh. Thus it has a high energy

density, with more than 1000 cycles of cycle life. This expensive system has to work

cooperatively with the thermal management system because it has to do pre-warm-up

for an electrolyte which is a waste of energy.

Last and one of the most preferred battery types on EV is a Lithium-Ion battery system.

This battery type has a compact structure with low weight. It uses Carbon as an anode

and lithium Cobalt dioxide for cathode product. The electrolyte is usually based on the

organic solvent of Lithium salt which is not a liquid electrolyte. This battery has a very

high power density when compared with lead-acid, it’s four times better than lead-acid.

With a long cycle life of this battery works in high efficiency. It is possible to do fast

charging. On the other side, there can be capacity loss due to wrong charging or

overcharging. It has to charge by constant current-constant voltage.

3.1.1 Thermal condition of Battery and Environment

All these battery models have their own charge and discharge characteristics.

And one of the main thing to have efficient battery charging cycle, working condition

is really important. Thus the thermal condition of the charging environment and

battery cell are very significant key factors. Environmental temperature directly affects

the charging time and discharging characteristics of the battery. High-temperature

levels will decrease the efficiency of the battery. To understand this behavior a simple

li-ion battery experiment can help to analyze this factor. This experiment is

experiencing with a Li-ion polymer cell which specification mention in the bellowed

table.

46

TYPE Nominal

Capacity

(Ah)

Nominal

Voltage (V)

Upper cut-

off

voltage (V)

Lower cut-

off

voltage (V)

Operating

temperature

Li-ion

polymer cell

1.5 3.7 4.2 3.2 -30 °C ~ 60

°C

Table 4. Case information

As a general perspective this experiment done between lower and upper cut-off levels,

and charge/discharge profiles monitor these cycles for 6 different temperature levels.

On the first graph, the constant charging current of 1 A experiences, on the second

graph discharging characteristics is at 0.25 A with different levels of temperatures. As

seen on the charging and discharging graphics, low environmental temperature levels

are more quickly charge, however on the discharge part of the cycle can quickly reach

to lower cut off level. According to these two graphics, the common assumption can

have approved which on the working condition of EV there need to be nominal

temperature conditions for a more efficient and long-life battery system. Furthermore,

the temperature level of this project varies between -15 °C ~ 25 °C, for higher

temperature levels capacity levels can occur on battery.

47

Figure 28. Charging characteristic in Thermal conditions

Figure 29. Discharging characteristic in Thermal conditions

48

3.1.2 State of Charge value of Battery

Secondly, the State Of Charge(SOC) is a very important factor that shows the

internal voltage level of the battery. A significant point of SOC, it can directly affect the

charging time of the battery by affecting the health of cells. Limits of SOC can

understandable more by figure 13. Regarding battery cells has a feasible working

range. This means that users of EV need to charge the car when the battery is around

20% and continue to charge till 80% for efficient battery cells. Charging time will be

stable and short in the long-term and the efficiency of the battery will be better for a

long which directly affects the charging and discharging cycle.

Figure 30. SOC levels

49

3.2 Charging Characteristics

Up until this point explained in this chapter were indirect factors on charging

time for the battery system. Charging time highly limited by the current capacity for

the battery. On the charging process current rate has to be high as much as possible

with the current capacity of the battery. The balance of proper current flow and voltage

flow will bring an efficient charging process. This controlled flow of voltage and current

is beneficiary for short charging time and battery health. Thus different combinations

of charging methods can select respect to needs. Significant battery charging methods

are constant current, constant voltage, and constant current- constant voltage.

Constant current (CC) is the basic method to charge the battery. The current value is

the same for all battery cells which are on series connection as a pack. As the charging

status of the batteries increases, the internal resistance rises up as well. That’s why

voltage, in order to continue charging It should be increased. Unless the current value

is very important in this because if selected charging current is too high in order to fast

charging, there will be a problem with overcharging and overheating which is

hazardous for the battery pack of vehicles.

Constant Voltage (CV) is basically a DC charging technique. This method needs a

simple and cheap design on the power system part. On the initial state of the charging

process, there can be high charging current can supply due to low internal resistance

of the battery, and this can damage battery cells. This problem can be solved by limiting

charging current value. So charging will start with filtered charging current and

constant voltage. As the charging status of the batteries increases, the internal

resistance rises up and charging current value goes down exponentially. This ensures

that the charge is completed with the leakage current, thereby reducing the likelihood

of the battery being overcharged compared to the previous method. However, because

of the exponential decrease in charging current, charging time will longer than the

constant current method.

Constant Current and Constant Voltage (CC/CV) method is the charging method

within two steps. Charging starts with constant current until a certain voltage level due

to the need for fast charging and prevents overcharging because of the high constant

voltage level. When SOC reaches that voltage level, the constant voltage step starts until

the final of the charging process. On the below chart charging procedure of these two

steps can be seen.

50

Eventually, just to clarify charging profiles on the side of power supply for common

battery type in the EV industry.

On Li-ion battery systems constant current and constant voltage, the charge profile is

more beneficiary for Fast charging. The process has to be done with 4 main stages.

These stages are shown in figure 15, in order to trickle charge, constant current charge,

constant voltage charge, and charge termination.

On NiMh battery system constant current and constant voltage, the charge profile is

preferable as well. However, the process consists of these four steps, trickle charge,

constant current, top-off charge, and charge termination. This charging profile can be

seen in figure 16 On NiMH transactions of current are sharper and as seen on the last

step cell voltage behavior is different than Li-Ion

Figure 31. Constant Current and Constant Voltage

51

Figure 32. Li-Ion battery charge profile

Figure 33. NiMH Battery charge profile

52

Trickle charge; this initial phase of charging, and it prepares deeply depleted cells to

charge. For Li-ion battery, when the battery cell voltage is below 3V, the cell can switch

to constant current charging of 0.1 C maximum. On the other side NiMh batteries,

trickle charge phase is happening for weak batteries, when the cell voltage is greater

than 0.9V per cell “fast” charge, or constant current charge can begin.

Constant current charge; Both for these two battery types, the battery cell voltage will

increase during trickle charge and on the threshold point charging current increases

instantly to operate constant current charging. As mentioned above because of rising

internal resistance, voltage rise during constant charging as well. This charging phase

should be in the 0.2C to 1.0C range.

Constant voltage; this phase is applicable only for Li-Ion batteries. Constant current

charge over and cell current exponentially decrease. The cell voltage already found the

top limited value in the previous step which 4.2 V in this graph. In order to maximize

performance, voltage regulation tolerance should be better than ±1%. On the side of

NiMH battery pack, when the voltage reached to top value at the end of the constant

current phase, the cell voltage won’t stay stable it will start to decrease.

Charge Termination; is the final part of the charging process. unless for Li-Ion

batteries, charge termination is a good option instead of continuity of trickle charging.

For NiMH batteries, a timed trickle charge ensures 100% of battery capacity use. When

the timed trickle charge is complete, charge termination is then necessary.

Under this charge profiles, charging stations has safety preferences. As mention in the

above thermal condition of the battery pack need to control in every step of the

charging process. For instance, the charging process has to stop if the battery

temperature is less than zero degrees or greater than 45 degrees. This working

condition must to have to provide from the station, otherwise battery packs of EV can

face with danger of explosion or battery cell health will lose the efficiency due to that

range of the vehicle shorten day by day.

53

To sum up, the charging time of the EV can cover in the below table. In this table,

charging is processing from 0% to 80 %, which is normally is not recommended for

battery pack health as mentioned in the SOC part. In all cases, chargers have 15%

efficiency losses and charging with of 0.5 C during CC phase, and the average current

is 0,05 C during CV phase. Each charging time shows minimum theoretical values.

Charge level and

Equivalent C Rate PHEV EV

EV

Heavy

Duty

Battery Capacity

(kWh) 10 24 50

Battery C rate

(Amps) 41 66 200

Charger Available power Charger

Efficiency (%) 85 85 90

Mode 2 3 kW Euro Domestic

Hours to 80% 3,1 7,8 14,8

Charge equivalent

C Rate 0,3 0,1 0,1

Mode 3 20 kW 3 Phase

domestic/public

Hours to 80% 0,5 1,2 2,2

Charge equivalent

C Rate 2,1 0,9 0,5

Mode 4 50 kW DC public Fast

Charge

Hours to 80% 0,05 0,1 0,2

Charge equivalent

C Rate 21,3 8,5 4,5

Table 5. Charging time

54

3.3. Wireless Charging

On the other side wireless charging technique need to take consider as well

because of the future. The wireless charging station has got different factor which

affects charging efficiency and time. Compared to conventional charging stations, the

battery system’s factor and onboard charger factors are the same. However, the biggest

efficiency problems are happening on the part of the wireless energy transfer part.

- Over high or insufficient Frequency on the transmitter.

- Location of couplers

- Distance between coupler

- Thermal condition of the coils

As mention in chapter 2, the electrical system is working with a really simple system.

Briefly, alternated current passing through a rectifier to obtain high-frequency

magnetic field on the transmitter coil, and later on, that magnetic field receiving by a

secondary coil which is assembled underneath of the vehicle. After that, the secondary

coil turns that the magnetic field into AC electric current and the rest is the same with

conventional charging techniques.

From the technical part of the wireless chargers, power transfer between the pads is

highly connected with the frequency of the magnetic field. For the two models of the

wireless charging station, CPT and IPT, if it needs to have a high power level of energy

there has to be right transfer on the right frequency level.

Secondly, the centering of the coils. Researches show that for the less loosely power

transfer transmitter and receiver pads’ middle points need to be face to face. Otherwise,

efficiency of power transfer will decrease. As a result of this, it will directly affect the

charging time.

On the other side, distance between two coils is significantly effective in the power

transfer efficiency of wireless charging systems. According to the test results of the

plug less company. They prepared a special construction to take down and up the

vehicle, to see them as vertically how efficiency is going to affect. So the testing of the

air gap started with 145 mm, and the vehicle goes up step by step. As seen from the

graphic, average efficiency did not change but instantly efficiency change on every step.

But the optimum level found in 190 mm.

55

Figure 34. The efficiency of power transfer regard on the vertical gap

Last but not least, the thermal condition of the pads is highly important. According to

Plugless company researches working condition of the pad is 32◦C and it can work

properly until 50◦C. However, the efficiency of the coils goes down slightly when the

temperature of the pad starts to rise.

Under these factors, basic wireless chargers work as Mode 2 charging station, with

maximum theoretical output is 7kW and 3 kW. Regarding this model, charging times

can be seen in the below table.

56

Model Charger output Charging time

Tesla Model S 7.2 kW 100 minutes

BMW İ3 7.2 kW 4.5 Hours

Nissan LEAF 3.3 kW 6-8 Hours

Chevrolet Volt Gen 1 3.3 kW 3-4 Hours

Table 6. wireless charging duration

58

Chapter 4 –COST ANALYSE OF CHARGING STATION AND

OPERATION

After all the technical advantages and disadvantages of the EV charging station,

the financial position of the system is a key point on this matter. Technically very useful

projects can be inaccessible on a financial basis. For instance, EV battery technology

had a huge drawback because of the cost of battery cells, however, because of

technological improvements and investments in the field of battery technology made

it easy to reach these products at affordable prices. These kinds of situations still

available in different positions of the EV industry. The maturity of technology will

bring affordability to the industry.

4.1. The user side of Charging Cost

To analyze the affordability of EV for users, however, because the system can

check by two perspectives. One for the customer side, charging/refueling cost of EV

and ICEV. Another point is if it needs the cost of infrastructure. For the first

comparison, a simple case can show all the situations easily. As seen in the table below,

two vehicles selected from the same brand and model, unless engine systems are

different. On the left side of the table, there is ICEV 2019 Volkswagen Golf with the

Gasoline engine, and on the right side, there is EV version Volkswagen E-Golf. With

one full tank, ICEV Golf has range approximately 680 km. EV Golf has a range of

around 200 km. To full up the tank of Golf with gasoline will cost to 36$.On the other

side E-Golf can full up with 5.6 $, however, the range is not sufficient to reach with the

Gasoline version. Charging cost is calculated by the average electricity cost in Italy,

0,176 €/kWh. By basic ratio, E-Golf can reach the range point of gasoline version in 3

full up and it will cost around 19.04 $. As mentioned in the previous chapter ICE type

vehicles has a great advantage in refueling time. Users of ICEV Golf can refuel their

vehicles less than 5 mınutes. On the other side EV, Golf users have to wait around 7

hours to fully charge their vehicles with Type 2. Adding to that system directly brings

extra costs for EV users, which is charging appliances that users have to but as initial

investment or they have to pay the extra charge to use charging stations of private

companies. Thus there will be an additional cost for every charging turn.

59

Internal Combustion Engine Vehicle Electric Vehicle

Model 2019 Volkswagen Golf 2019 Volkswagen e-Golf

Fuel Type Gasoline Electricity

Weight 1336 kg 1540 kg

Km/full tank ~680 ~200

Cost to drive

40 km 2.10 $ 1.12 $

Cost for 1

refuel 36 $ 5.6 $

Capacity 45 liter 32kWh

Refuel time Less than 5 minutes 7 hours (TYPE 2)

Table 7.Case information on cost

60

4.2. Cost of Charging Techniques

The financial side of the charging station depends on the type of charging

station. The cost of charging stations cannot be limited by the only cost of charging

stations. There are fix costs on the charging stations. These fix cost categories are;

-Cost of installing equipment and where relevant the cost of site preparation

-Cost of utility system upgrade

-The cost of the charging equipment

The first two can be called as pre-operation work which covered everything except

charging equipment. Table 8 is the list of the cost for a single charging station for the

residential and commercial.

61

Charging

Techniques Mode

1 AC

Mode

2 AC

Mode 3

AC

Mode 4

DC

Mode

4*1 DC

Wireless

Charger

7.2 kW

B.S

.

Installation - 1216 € 2.791 € 20.325 € 20.325

€ 1216 € -

Site Preparation -

-

2.695 € 11.229 € 11.229

€ - -

Utility Service - - 3.594 € 15.720 € 15.720

€ - -

Transformer - - 5100 € 29000€ 36000 - -

Cost of Charging

Station - -

450 -

2500 €

15.000 –

35.000 €

40.000-

60.000

€

12.000 € -

Cost of Cable and

Accessories 180 € 180 € 180 € - - 1.000 € -

Table 8. Price list of charging station and accessories

Starting from the basic levels to analyze this, from the end-user side Mode 1 and Mode

2 type charging stations do not need extra EVSE cost, because connection cable of the

vehicles is coming with a car from the factory. Even users need to buy a new cable or

new accessories for mode 1 and mode 2, it’s easy to reach via car-technology markets.

As mentioned in chapter 2, Mode 1 and 2 are directly feeding by a household socket.

Thus there is only cost for cable and electricity consumption to charging up their

vehicles. Unless in some cases Mode 2 charging station would require the installation

of new circuitry. The power demand of mode 1 and 2 won’t require the utility

infrastructure upgrade specifically to the resident. Unless, if several charging station

operates in the same circuit, it can be apartment or neighborhood, due to peak demand

62

on the system, it mac place the existing transformer at risk of overload and require an

upgrade. Adding to this price of the average quality cables for these modes is starting

from 180 €.

More advanced level charging stations need proper electric circuitry. As known, mode

3 charging stations are feasible to use both as Home and commercial. Adding to that

they are consist of a control box, cable and side accessories if the user needs. With the

purpose of commercial use, Mode 3 charging station requires some form of wiring

extensions, side product as a sign and constructional works to do. Installation costs are

highly depending on location; thus pre-operation costs can vary widely. This can

averagely cost 2.800 €. Generally, the cost of these ready to use wall chargers is starting

from 450€ and it is easy to purchase and connect to the house electricity system by

electrical technicians. Mostly for these wall chargers are coming with standard Type 2

connector but for extra cables or if there is no cable with wall charger it can cost around

180- 200 € as modes 1 and 2. Tesla company is a good example to understand the

average price of these products. Tesla US prices for wall connectors are 500$. Which

is not a really high price to charge EV faster than mode 1 and mode 2.

Mode 4 is a bit more expensive system among others. Mode 4 charging stations include

their own AC-DC converters and also there is a control box of it. Because of the

infrastructure cost and initial cost of charging stations, these charging stations are

mostly affordable to use as commercial aspects. Private companies serving these

charging stations as a charging pool, thus at the same time they can serve charging

service to more than one user. Carpool systems need a huge investments approximate

price of up to 50 kW DC fast charger, which can charge two vehicles at the same time,

is 35.000 €. Commercial installations can cost up to 50.000€ with all pre-operation

costs, but it depends on the locational state of the area. Even if users want to set a

private charger at House/office, it can cost around 15.000 €. These prices are only

charging station cost, there is also additional infrastructure cost in case of need,

because of insufficient electricity infrastructure in the building. If there is more than

one charger that connects to the same local network and transformer, the company

needs to do a utility infrastructure upgrade to provide power to stations. This case is

must to have a case for Mode 4 and Mode 4*1 charging stations because of increased

demand on locational networks. A new transformer can individually cost up to 30.000

€ only to energize these stations.

63

Adding to these modes, ultrafast chargers have to be mentioned as well. These new

advance level charging stations will be in the streets as well in the next years. Even that

nowadays heavy-duty EV’s are using these charging stations. Ultrafast charging

stations are coming with the need of well electrical infrastructure. Thus even carpools

or private ones need special transformer boxes with charging stations, which will

increase the initial cost of charging stations. According to the European Parliament

report on EV industry, Spöttle et al. (2018), single charging point for the public

transportation cost can vary from 40.000 to 60.000 €, which cost covers only chargers

with private substations, there is also additionally infrastructure and operation

expenses has to be added. This shows that the electric transportation system for public

use needs a strong financial background for governments. Even though vehicle costs

are higher than ICE vehicles for all these categories. It means that costumers of EV

have to pay more initially, however in the long term they can save that difference by

the help of less amount of charging and operational costs.

Moreover, to compare with conventional charging modes, wireless charging, and

battery swap techniques can give a good perspective about why cable systems are still

preferable by the user side. As it has seen wireless charger cost, one of the basic models

which equal to mode 2 charging station, will cost around 13.000 €. The price is

consisting of a house type wireless charging station, transmitter pad and receiver pad,

which pad install to the vehicle by-charger company. When compared with level 2

charging station as an economically. By today’s technology, it is obvious that the

wireless charging method for EV is not affordable, even if has advantages both the user

side and the technical side. But private companies still working on this to make it more

accessible technology in the near future. More powerful models of the wireless

charging models are still on the project phase. Thus, on-road wireless chargers’ costs

unforeseen for end-user side.

Lastly, the battery swap system couldn’t have actualized in the world. This technology

still under the process of research and development to fix the key point disadvantages.

However, according to financial reports of these projects, the battery swapping

technique needs to have a huge investment to change the behavior and the working

procedure of electric vehicle industry. Except for the fact that evolving into a common

battery pack system of the vehicle industry, autonomous battery swapping stations will

bring huge costs into the system and also operational cost will reflect customers.

Adding to that battery swapping costs will also contain energy prices to charge up the

battery.

64

In the battery swap system, an e-motorcycle example needs to check as well, to at least

see the real life product cost. Battery swappable motorcycles are using in share type

programs of companies. One example of this system is Gogoro from Taiwan. According

to the driver trip, they can swap the battery from one of the battery stations in the city.

These stations include 40 battery pack as mentioned in chapter 4. The cost of the trip

is depending on the drivers’ trip range. The maximum range can be 80 km according

to company, and Gogoro company mentioned that full charge batteries cost per

motorcycle cost 1/3rd to full fill the ICE motorcycle with gasoline.

66

CHAPTER 5 - WORLDWIDE

The electric vehicle industry is getting more common across the globe. By the

reason of raised energy consumption from fossil fuels and the economic disadvantages

of the ICE vehicles are significant road making factors of the growing electric vehicle

industry. Especially in North America, Europe, China, and Japan ındustry highly in

demand. Eventually, these regions are meeting with innovations in this field by EV

companies. According to IEA global electric vehicle outlook 2018 report, the growing

rate of increase can see in Figure 34.

Figure 35. Number of electric cars in circulation, 2013-2017 (in millions)

67

All these markets are still dominated by fossil fuel vehicles, but the rating of the electric

vehicle is growing fast. The mentioned values on the report only show 2% in the

automobile industry. This means that there is still a long way to become common in

the globe for electric vehicles. These growth markets, private companies, and

governments doing their future plans to invest large amounts to make electric vehicles

more accessible with costumers. In these regions, the main top five competitors are

Nissan (Japan), Tesla (US), Toyota (Japan), Ford Motor (US) and Volkswagen

(Germany). These competitors have significant projects with companies who work on

the different scopes of the industry.

Primarily these projects continue to decrease the battery price, increase the range of

the vehicle and decrease the charging time of battery packs. Regarding forecast reports,

lithium battery prices will decline year by year and with the risen capacity density of

battery packs, vehicle ranges will rise as well. On the other hand, projects about

charging stations still developing, with the aim of cheap, sustainable and fast-charging

stations. For this matter, governments do investments on electrical network and

charging infrastructure due, European parliament,2019. Adding to this, they believe

that lithium-ion battery percentage on the market will boom especially on electric

vehicle areas, and the forecast graph can see in figure 35.

Figure 36. Lithium-ion batteries placed on the global market (cell level, tonnes)

68

In the light of these data, if we specifically examine countries whose systems have

reached a certain maturity level, each region has different regional, technical and

economic advantages and disadvantages.

In the high proportion of Europe, electric vehicle system established, for all that

companies focusing on to upgrade the electrical network, extend the fast-charging

station, decrease the range anxiety of users from both technical and accessibility of

charging station sides and lastly heavy-duty vehicles to use on public transportation

and commercial areas. Furthermore, under the purposes of maintaining financial

benefit to users, and tried to establish a system that will reduce the supply of demand

from the electricity generation in the network, which is called the vehicle to grid. The

common goal of these developments is also looking for direct benefits to decline the

CO2 emission level by increasing the usage of electric vehicles. As mentioned in chapter

1, the Paris Climate Agreement was a huge step to the help of growing this industry

across Europe.

On the other side of the Ocean, the USA have challenges with their own infrastructure

about to make it more sustainable, more efficient and more accessible for EVs. Adding

to that, ın US region, heavy-duty electric vehicle projects, different sizes of family

electric vehicle projects having significant investments. American market players aim

to dominate the market globally. Thus Tesla and Ford Company investing in the

electric vehicle industry and not only to manufacture the vehicle, but they also have

great developments about charging stations as like Tesla Superchargers.

Market shareholder The Far East countries. With the help of the population levels and

strong economic wealth, China and Japan became a market former player in a specific

field of the EV industry, which countries have the largest charging point web in the

world. CHAdeMo charging station system is a great example for Japan. Not only on the

local market, but they also created large web across Europe. Just in Europe, they have

got 9200 charging stations, on the global base this number is 25300 charging points.

Adding to this, With the largest amount of Lithium resources in the world, China is the

biggest producer of Li-Ion battery systems. China maintains the sustainability of these

achievements by using advantage of cheap workforce and research and developments.

On the local side, these two countries already established their electric vehicle web. On

the purpose of to spread electric 2 wheel vehicles in their city transportation instead of

conventional 2 wheel vehicles, both two countries have investments, which can also

great opportunity to become a market shareholder in European countries or countries

69

primarily use as a transportation vehicle as like Latin American countries, Indıa,

Taiwan. Even now, there is lots of Far East company from these countries, supplying

e-motorcycle share services with basic charging stations, in their different small

markets around the world.

Unfortunately, these three regions are covering 80% of the EV industry owing to their

economic wealth, improvement in technological fields and strong market structures.

The rest of the countries still have a path to get a strong electric vehicle industry. Some

of these countries can’t afford to make it common, mostly because of economic

conditions or insufficient electrical infrastructure.

One of the significant emerging country group for the electric vehicle in the globe is

South American countries. After conventional vehicle type its hard challenge for them

to switch BEV or PHEV. Starting from the financial problems of Latin American

countries, Governmental Taxes create a large amount of extra cost on the vehicle cost,

due to that costumers hesitate to step forward to this technology. Even in the largest

markets of South America, which are Colombia, Mexico, Brazil and Chile, there is a

problem of very few charging stations across all countries/cities, there is huge range

anxiety due to fragmented public charging landscape on the side of public charging. On

the house charging, there are insufficient charging speeds due to poor electric grids

and also even in the middle of the city centers, costumers need to upgrade their electric

infrastructures. And on the other side, local companies or partners do not have

experience with BEVs, even there is a problem of the inexistence of service companies

for specific fields. According to number of charging stations, CHAdeMO has got 80

fast-charging station points across South America. In the below figure, charging station

availability can see.

70

Figure 37. Charging Station Availability map

Africa has to divide into 3 main districts to analyze, as like North Africa, Mid African,

and South Africa. According to reports, this continent having adaption to electric

vehicle technology really slowly. Some specific countries have more potential to move

forward in this industry, because of technical infrastructure. For example, from the

Mid-African countries, Kenya has a great system in urban areas. Local companies are

mostly working on improvements in the infrastructure and sustainability of electricity.

It means that they are not a manufacturer of the technological components on this

term. On the other side, South Africa has the potential to increase the number of EVs

in the field. Automakers entering the market year by year. Even the number of sold

vehicles is not really high for this country. Just in 2018 South Africa market leader

BMW sold only 62 electric vehicles in total. South African charging station network is

currently including 120 public charging station which is an actually good number when

the market size compared with the East European market. On the north side of the

continent, Egypt, Morocco, Algeria, and Tunisia have the opportunity to connect with

European countries. Thus pilot projects can see in these countries more often. French

Renault, Peugeot, having a great connection with the northwest African countries in

these years. Unless by the established automobile industry, Egypt just started to do

investments in this area. These countries across Africa, not only interest in mid-class

electric vehicles. In most of them, e-motorcycles have great potential to use in private

transportation. And also for the public transportation E-bus systems have demand

especially in South Africa.

71

Figure 38.South Africa charging station map

Australia has different challenges when we compare it with Latin America. Because of

the distribution of urban areas, the charging system is not separated properly in all

countries. Thus their biggest problem is range anxiety. As seen in Figure 38, the Tesla

supercharger point map is illustrated. Lack of charging service points is pushing the

companies to invest more in the rural areas by cheaper charging station systems or

users of the vehicles go towards to self-charge system by household sockets. Totally 210

CHAdeMo charging station working, and there are 16 Tesla superchargers on the

system at investments of these two companies continue to system day by day. In urban

areas, the usage of electric vehicles rises day by day. According to the guardian forecast

prediction for EV ındustry in Australia, half the sold vehicles will be EV in 10 years.

72

Figure 39. Tesla Charger Map

74

CHAPTER 6 – CONCLUSION

The main contribution of this thesis is to create the right path on the mind of

users who own electric vehicles or will. As seen in the chapters, electric vehicle charging

stations do not cover only one subject. The conclusion side will be in two-part, at first

current situation, and secondly future of the charging systems.

In today’s electric vehicle industry, mode 3 and mode 4 is a preferable charging station.

Both of them categorized as fast charging with the main difference of Mode 3 is AC,

mode 4 is DC power. Other levels of the conventional charging stations have

disadvantages when compared with mode 3 and mode 4. However, Ultra-fast charging

stations will take the place of them in the future when that technology will become

affordable and usable with vehicles and electrical network systems. On the other side

wireless chargers are more preferable for 2 wheel electric vehicles, on the mid-class

electric vehicles or heavy-duty ones there is no common preference because wireless

charging stations do not maturate enough to take the place of conventional charging

stations, both for technical and financial. Battery swapping technique was also not

feasible on the user side, with the only advantage to recharge the car in 90 seconds but

there are still disadvantages like que for a battery swap, out of stock battery pack.

On the side of the market mode 3 and mode, 4 is preferable as well by vehicle

companies. Because of the maturity of the technology in these charging stations, it

creates more benefits than others with ease of low-cost accessibility and wide service

web with current state infrastructure or at least without a high upgrade on the electric

network system. On the commercial side, High powered systems are for trucks and

other but due to the cost of vehicles and stations, still, internal combustion engine

buses and trucks are more preferred by users. Adding to that, Lithium-ion batteries

took place in the vehicles which are still on developing process to aim for long-range

and efficient charge and discharge cycle.

In the long term, the drawbacks of these systems need to be solved. Users of the electric

vehicle won’t wait to charge up the vehicle or on the driving term, nobody wants to

have a problem of range anxiety. That’s why in the near future high power chargers

need to take place of the current ones. With today’s information, we can predict that

ultra-fast chargers will take the place of the others. In other words to say that the

infrastructure of the cities will change and will need to upgrade the substations, to

distribute a high capacity of power with efficiency. Besides battery capacities need to

develop as well under the purpose of long-range and short charging time. In the next

future, the range of the vehicles needs to increase from 120 km to at least 600 km,

which mid-class conventional vehicles range.

75

Last but not least, wireless chargers are going to be a problem solver to wait on the

charging stop with their on-road charging techniques and also it will decline the

workforce of drivers while they connect the cable of chargers to their vehicles.

According to researches and developments, there are some disadvantages to the

wireless charging method. Especially magnetic transfer of electric is such an important

research subject in these days. Because of the different important parameters charging

efficiency can change easily both for the parking slots and on-road systems. Another

disadvantage of the wireless charging stations is vehicles’ charging system adapts to

conventional cable charging systems. Thus, electric networks, substations’ capacity,

and distribution inside of the city and roads need to upgrade for this system.

Consequently, an upward trend in the electric vehicle industry will bring upgrade needs

to the infrastructure and charging stations. Investing in conventional cable charging

stations looks much more acceptable for both economic and technological maturity.

However, wireless charging stations have a chance to change the dynamics of the

industry, but it will cost more expensive to private companies and governmental

organizations. In today’s technology, DC fast chargers and AC fast chargers are more

reasonable to use, and in the near future if Ultra-fast DC chargers get common,

conventional charging stations will supply the increase raised demand from user side.

But of course, vehicles need to work coordinate with DC fast chargers, because of this

problem many vehicles cannot charge by Dc charging stations as like as Smart Electric

Vehicle models and Mercedes Benz B class.

77

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