A High-Performance PHEV Battery Pack€¦ · 13/05/2013 · A High-Performance PHEV Battery Pack....
Transcript of A High-Performance PHEV Battery Pack€¦ · 13/05/2013 · A High-Performance PHEV Battery Pack....
A High-Performance PHEV Battery Pack
PI: Mohamed Alamgir and Geun-Chang Chung
LG Chem Power / LG Chem
May 13, 2013 Project ID: ES002
“This presentation does not contain any proprietary, confidential, or otherwise restricted information”
ABS/EP
NCC/Polyolefin
PVC/Rubber
Acrylate
LCD Polarizer
LCD Glass
OLED Materials
Color Filter
Lithium-Ion Batteries for
- Mobile Phone, Laptop, Power Tool
- Hybrid & Electric Vehicles
- ESS
Energy
Solution(10%)
Petro- chemicals
IT & Electronics
Materials $ 22 B (2012) IT &
Electronics Materials
Petro- chemicals
Energy
Solution
Revenue R&D Expense
Energy Solution Petrochemicals IT & Electronics Materials
LG Chem at a glance
Battery Pack Concepts, Design and Prototype Builds
Battery Management Systems Sales and Customer Support
LGCPI
$300M+ investment with ARRA funding
Groundbreaking: Summer 2010
Production begins in 2013
LGCMI
Troy, MI Sales & Pack R&D
Holland, MI Cell Manufacturing
Cell Structure: Unique Stack- and-Fold Design
Positive terminal
Negative terminal
Lead film (insulation tape)
Stack and Folded cell
Bi-cell Laminated film
SRSTM
Stacking of Plates & Folding
SRSTM provides superior abuse-tolerance By improved mechanical and thermal stability By preventing internal short circuit By providing lower shrinkage
Nano scale Ceramic Particles
Micro porous Polyolefin film
Proprietary Safety Reinforcing Separator (SRSTM)
Significantly higher puncture strength than conventional separator
• Project Start: April 1, 2011 • Project End: December 31, 2013 • Percent complete: 79%
• Total project funding: $9.6M • DOE share: $4.8M • Contractor share: $4.8M • Funding for FY12: $2.0M
Timeline
Budget
Barriers
• LG Chem, INL, SNL, NREL
• Project lead: LGCPI
Partners
Overview of Current Program
• Specific Energy and Power
• Cycle- and Calendar-life
• Cell Cost goal of <$200/kWh
• Efficient Refrigerant-to-Air cooling system
Develop a cell suitable for use in the PHEV-40 Mile program using next generation, high capacity Mn-rich cathode materials.
A key goal of the program is to lower the pack cost to close to the $3400 target.
Improve upon the Refrigerant-to-Air cooling system we have developed in our previous program with respect to mass, volume, cost and power demand.
Deliver cells and battery packs to USABC for testing.
Objectives
PHEV 40-Mile Battery Pack Goals
Characteristics at EOL Units
Requirements for
40-MileProgram
Reference Equivalent Electric Range Miles 40Peak Pulse Discharge Power, 2 Sec kW 46Peak Pulse Discharge Power, 10 Sec kW 38Peak Regen Pulse Power, 10 Sec kW 25Available Energy, CD4 mode, 10kW rate kWh 11.6
Available Energy, CS4 mode kWh 0.3
Minimum round-trip Energy Efficiency5 % 90Cold Cranking Power at -30°C, 2 sec / 3 pulses (2-10-2-10 2)
kW 7
Cycles; 5000
MWh 58CS HEV Cycle Life, 50Wh Profile Cycles 300,000Calendar life at 35°C Years 15Maximum System Weight Kg 120Maximum System Volume Liters 80Maximum Operating Voltage Vdc 400Minimum Operating Voltage Vdc >0.55VmaxMaximum Self-Discharge Wh/da
y50
1.4
(120V/15A)Maximum System Production Price @100k units/year US$ $3,400
CD Life / Discharge throughput
System Recharge Rate at 30°C kW
Study high capacity, Mn-rich, layered-layered cathode materials from multiple vendors.
Characterize and Improve the performance, life and abuse-tolerance of Mn-rich cathode materials.
Optimize, fabricate and deliver battery packs based on Refrigerant-to- Fin indirect cooling system.
Approach/Strategy
Mn-rich cathode materials from multiple sources have been evaluated.
Built cells with control of various cell fabrication parameters/processes such as electrode formulations, formation protocol etc. to identify conditions optimum for performance and life.
Studied the effect of operational voltage ranges on energy, power and life.
Studied the effect of electrolyte additive on life. Surface coatings on cathode particles considerably
improve the durability of Mn-rich cells.
Technical Accomplishments/Results
1st Gen cells (24Ah) were built and sent to National Labs for evaluation. Results showed the need for significant improvement in life.
Battery packs using refrigerant-to- fin indirect cooling system have been designed and optimized with respect to Volume Weight, Robustness, and Power demand.
Testing of prototype packs under various heat-loads using different
driving profiles have been carried out. Data show good efficacy of this cooling system.
Prototype packs have been built and delivered to National Labs for evaluating their cooling efficiency.
Technical Accomplishments/Results
Baseline studies with Mn-rich cathodes show capacities as high as ~ 250 mAh/g at RT.
Strong dependence on rate.
0 50 100 150 200 250 3002.5
3.0
3.5
4.0
4.5
Volta
ge (V
)
Discharge capacity (mAh/g)
0.1C 1C
0 50 100 150 200 250 3002.5
3.0
3.5
4.0
4.5
Volta
ge (V
)Discharge capacity (mAh/g)
0.1C 1C
Sample A Sample B
Results- continued……
Rapid increase in DC resistance at low SOCs. This can limit the usable SOC range for PHEV
applications.
Results- continued……
0 10 20 30 40 50 60 70 80 90 1000.0
2.0
4.0
6.0
8.0
Resi
stan
ce (m
ohm
)
SOC (%)
Discharge resistance Regen resistance
Charging to voltages such as 4.5V to access higher capacity leads to significant gas evolution. This causes swelling and premature cell failure.
This gas generation necessitates considerable adjustment to cell processing conditions, such as formation.
Results- continued……
Co Mn Ni 24 ppm 145 ppm 19 ppm
High voltage operation results in severe Mn dissolution in regular electrolyte.
Results- continued……
0 20 40 60 80 100 120 140 1600.0
20.0
40.0
60.0
80.0
100.0
25oC 4.5V~2.0V 1C/2C cycle
Norm
aliz
ed c
apac
ity (%
)
Cycle
Max charge voltage has a strong influence on cycle-life.
Results- continued……
0 100 200 300 400 5000.0
0.2
0.4
0.6
0.8
1.0
1.2
67%72%
28% 4.35V-2.5V DOD100 4.5V-2.5V DOD80 4.5V-2.5V DOD100
Nor
mal
ized
Cap
acity
Cycle
Discharge cut-off voltage has significant effect on cycle-life.
Results- continued……
0 50 100 150 200 250 300 350 4000
20
40
60
80
100No
rmali
zed
capa
city (
%)
Cycle
4.4V~2.0V 4.4V~3.18V
45oC 1C/2C cycle
Electrolyte additives appear to enhance cycle-life.
45oC 4.5V~2.0V 1C/2C cycle
0 20 40 60 80 100 120 140 160 180 2000
1020
30
4050
60
7080
90
100
Nor
mal
ized
cap
acity
(%)
Cycles
Ref. Ref. + Add#5 Ref. + Add#7 Ref. + Add#5 & Add#7
Results- continued……
Improved separator helps to enhance cycle-life.
45oC 4.45V~2.5V 0.5C/1C cycle
Results- continued……
0 20 40 60 80 100 120 140 1600.0
6065707580859095
100105110
Reference New Separator
Cyc
le R
eten
tion
(%)
Cycle Number
Surface coating enhances cycle-life.
Results- continued……
0 20 40 60 80 10070
80
90
100
ALD Mn-rich (mono cell) Bare Mn-rich (mono cell)
Nor
mal
ized
Cap
acity
Cycle
25oC 4.35V- 2.5V 0.5C/1C cycle
Surface Coated - Red Bare- Black
Surface coating reduces resistance rise during cycling.
Results- Effect of Surface coating…
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
HV Formation/SOC 100 EIS Measurement
Z''
Z'
Pristine Formation (R3 = 86.7 Ωcm-2, R4 = 34.8 Ωcm-2) 2ALD-Pristine Formation (R3 = 103 Ωcm-2) 5ALD-Pristine Formation
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
50 Cycle/SOC 100 EIS Measurement
Pristine Formation (R3 = 71.4 Ωcm-2, R4 = 58.0 Ωcm-2) 2ALD-Pristine Formation (R3 = 48.8 Ωcm-2, R4 = 12.1 Ωcm
Z''
Z'
Bare- Blue Coating I- Red Coating II- Red II
Bare- Blue Coating I- Red
• Amount of Al2O3 secondary ion (AlO-, AlO2-) after cycling was decreased, while that
of AlF3 secondary ion (AlF2-, AlF4
-) was increased. - Al2O3 was changed to AlF3 by the reaction of Al2O3 with HF.
• AlF3 is known to show lower resistance to Li ion diffusion than Al2O3.
Results- Effect of Surface coating…
Before Cycling After Cycling
Requires refrigerant loop; but: Avoids coolant fill and maintenance, obviates need for
complex coolant manifolds and risks of leaking.
Phase I- Two thermal zones: Refrigerated compartment (cells, evaporator, fan) Ambient compartment (controls, compressor, condenser,
fan)
Results: Refrigerant Cooling System
Thermal
Results: Phase II Cooling System- integrated design
Electronics
Cells
A refrigerant loop is used to cool the cold-plate at the bottom of the battery pack which, in turn, is attached to solid fins located between the cells.
Picture of a Pack delivered to USABC
Results: Thermal and Electrical Compartments
24.7
25.8
26.326.5
26.3 26.426.1
25.9
25.1
20.0
21.0
22.0
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
CT1 CT2-3 CT4-5 CT6-7 CT8-9 CT10-11 CT12-13 CT14-15 CT16
Tem
pera
ture
(C°)
Thermocouple Name
10Nov2011 USABC Module Thermal Testing Test 4--Repeated US06 Drive Cycles (derated) from 90%-20%SOC, Module at Room Temp, 15°C cold plate, 1mm Al fin - 90deg bend-
TC Cell Temps at Worst dT(1.8C°)
Results: Cooling System- Module Level Testing
US06 Drive Profile SOC range = 90- 20% 25oC, Cold-plate at 15oC Max ∆T among cells : ~2o C
Efficient cooling- satisfies target
Results: Cooling System- Pack Level Testing UDDS Drive Profile SOC range = 90- 20% 25oC, Cold-plate at 15oC Max ∆T among cells : ~0.5o C
Results: Cooling System- Pack Level Testing UDDS Drive Profile SOC range = 90- 20% 25oC, Cold-plate at 15oC Max ∆T among cells : ~0.5o C
Future Work
Studies to develop Gen 2 of cells having improved life and performance are currently underway. These include:
Use surface-modified cathodes Use of new electrolyte
compositions/additives.
Delivery of Gen 2 cells to National Labs for evaluation with improved power and life.
Delivery of final packs to National Labs.
OEM Vehicle GM Chevy Volt Ford Focus BEV Hyundai Sonata Hybrid Volvo XC 60 Renault Zoe
Use of LGC’s Cells in Production Vehicles
These cells benefitted directly from the development programs LGCPI had with USABC.
LGCPI team (Paul Laurain, Satish Ketkar, Jongmoon Yoon and Kwangho Yoo)
LG Chem team (Geun-Chang Chung, Hoejin Ha, Song-Taek Oh, Jaepil Lee)
USABC for their financial and technical support in course of these programs.
Paul Groshek- Program Manager
INL (Jeff Belt), NREL (Ahmad Pesaran, Kandler Smith), LBNL (Vince Battaglia) and SNL (Chris Orendorff) for valuable technical support
Acknowledgements