Ultra capacitors (Super capacitors)

SAISRI.R16031DA708

Nano Electronics & Photonics

ABSTRACT• Super capacitor also known as electric double-layer

capacitor (EDLC), super condenser.• Compared to conventional electrolytic capacitors the energy

density is typically on the order of hundreds of times greater than the comparison with conventional batteries like fuel cells.

• In this article the use of super capacitors likes hybrid power supply for various applications is presented.

• The main application is in the field of automation.• Carbon Nano tubes,Graphene,Carbon Aerogel are mainly

used to develope super capacitor using Nano technology.

Introduction• Capacitor• Super Capacitor• Types of Super Capacitor• Construction and Working of Super Capacitor• Super Capacitor Vs Normal Capacitors• Advantages & Disadvantages• What are the Technologies used• Applications• Conclusion• Reference

Capacitors• In general, capacitor is a device to store the

charge in an electric circuit. • Basically, a capacitor is made up of two

conductors separated by an insulator called dielectric.

• The dielectric can be made of paper, plastic, mica, ceramic, glass, a vacuum or nearly any other nonconductive material.

Super Capacitors

• Super capacitors can be defined as a energy storage device that stores energy electrostatically by polarizing an electrolytic solution.

• Super capacitors are also known as double-layer capacitors or Ultra capacitors.

Supercapacitor Types

Supercapacitor Types• Double-layer capacitors – with activated carbon electrodes or

derivate with much higher electrostatic double-layer capacitance than electrochemical pseudo capacitance.

• Pseudocapacitors – with transition metal oxide or conducting polymer electrodes with a high amount of electrochemical pseudo capacitance.

• Hybrid capacitors – capacitors with asymmetric electrodes one of which exhibits mostly electrostatic and the other mostly electrochemical capacitance, such as lithium-ion capacitors.

Construction

• Ultracapacitor consist of a porous electrode

• Electrolyte• A current collector

(metal plates)• A membrane, which

separates, positive and negative plated is called separator

Working

Diagram shows the formation of double layer

c

Super capacitors Vs. Rechargeable Batteries

Super Capacitors:• Higher power density • Much faster charge and

discharge rate• Environmentally friendly • Extremely low internal

resistance or ESR • High efficiency (97-98%)• Over a million charge-

discharge cycles

Rechargeable Batteries: • Have higher energy density • Typically 200–1000 charge-

discharge cycles• Contain highly reactive and

hazardous chemicals • Negatively effected by low

temperatures

Advantages• Long life: It works for large number of cycle without wear and

aging.

• Rapid charging: it takes a second to charge completely.

• Low cost: it is less expensive as compared to electrochemical battery.

• High power storage: It stores huge amount of energy in a small volume.

• Faster release: Release the energy much faster than battery.

Disadvantages• They have Low energy density

• Individual cell shows low voltage

• Not all the energy can be utilized during discharge

• They have high self-discharge as compared to battery.

• Voltage balancing is required when more than three capacitors are connected in series.

Development in Super capacitor using Nano technology

• Nano technology is used for expanding the possibilities and practically of an alternative energy future.

• Nano technology uses for producing highly efficient and effective nano technology are showing more effective future.

• Carbon Nano tubes, carbon aerogels are used for super capacitor plates or electrodes.

• Sodium perchlorate or lithium are used as electrolytes.• Polyacrylonitrile is used as a separator which has thickness

of (0.3-0.8nm).• Aluminum as a packing component.

Carbon Nanotubes

Approximately 1/50,000th the width of a human hair

Strongest and stiffest material on earth (>300 X Steal)

Low density Semiconductor

Carbon Aerogel

• Composed of nanometer sized particles covalently bonded together

• High porosity (>50% under 100 nm)

• Large surface area (400–1000 m²/g)

- Aerogel is a low-density solid derived from gel that has had the liquid component replaced with a gas.

Applications• They are used in electronic applications such as

cellular electronics, power conditioning, uninterruptible power supplies (UPS).

• They are used in industrial lasers, medical equipment.

• They are used in electric vehicle and for load leveling to extend the life of batteries.

• They are used in wireless communication system for uninterrupted service.

Different styles of supercapacitors

Flat style used for mobile

components

Typical knob capacitor for PCB

mounting used for memory backup

Radial style of a (lithium-ion

capacitor) for PCB mounting

used for industrial

applications

Conclusion

• Ultracapacitors (Supercapacitors) offer a promising alternative approach to meeting the increasing power demands of energy storage systems and electronic devices.

• With their high power density, ability to perform in extreme temperatures, and millions of charge-recharge cycle capabilities, supercapacitors can increase circuit performance and prolong the life of batteries.

THANK YOU

References

• 1.http://www.tecategroup.com/ultracapacitors-supercapacitors/ultracapacitor-FAQ.php#What_is_end_of_life_and_failure_mode_for_an_ultracapacitor

• 2. http://batteryuniversity.com/learn/article/whats_the_best_battery