2. What is Capacitor?
A capacitor (originally known as condenser) is
a passive two-terminal electrical component used to
store energy in an electric field.
3. What is Supercapacitor?
A supercapacitor or ultracapacitor is an
electrochemical capacitor that has an
unusually high energy density when compared
to common capacitors. They are of particular
interest in automotive applications for hybrid
vehicles and as supplementary storage for
battery electric vehicles
4. History
The first supercapacitor based on a double layer
mechanism was developed in 1957 by General Electric
using a porous carbon electrode [Becker, H.I., “Low
voltage electrolytic capacitor”, U.S. Patent 2800616, 23
July 1957].
It was believed that the energy was stored in the carbon
pores and it exhibited "exceptionally high capacitance",
although the mechanism was unknown at that time. It
was the Standard Oil Company, Cleveland (SOHIO) in
1966 that patented a device that stored energy in the
double layer interface [Rightmire, R.A., “Electrical energy
storage apparatus”, U.S. Patent 3288641, 29 Nov 1966.].
5. Basic Design
• Electrochemical capacitors (supercapacitors) consist of two
electrodes separated by an ion permeable membrane
(separator), and an electrolyte electrically connecting both
electrodes. When the voltage is applied, ions in the electrolyte
form electric double layers of opposite polarity to the
electrode's polarity.
• For example, positive electrodes will have a layer of negative
ions and negative electrodes will have a layer of positive ions.
7. Features
Such energy storage has several advantages
relative to batteries.
Very high rates of charge and discharge.
Little degradation over hundreds of thousands
of cycles.
Low toxicity of materials used.
High cycle efficiency (95% or more).
8. • High energy storage.
• Wide working temperature(-400c to 600c).
• Eco-friendly.
• Quick charging time.
• Maximum life cycle.
• High cycle efficiency (95%).
• High specific power up to 17 kW/kg.
• Extremely low internal resistance.
• Safe.
ADVANTAGES
9. Disadvantage
The amount of energy stored per unit weight is
considerably lower than that of an electrochemical
battery (3-5 W.h/kg for an ultracapacitor compared to
30-40 W.h/kg for a battery). It is also only about
1/10,000th the volumetric energy density of gasoline.
The voltage varies with the energy stored. To effectively
store and recover energy requires sophisticated
electronic control and switching equipment.
Has the highest dielectric absorption of all types of
capacitors.
10. Applications:
Maintenance free applications
Public transportation, HEVs, Start-Stop System
Back-up and UPS systems
Systems of Energy Recuperation
Consumer electronics
11. • Supercapacitors may be used where high power or energy storage
is required.
• Supercapacitors can be used widely because of their long life &
short charging time.
• On the other hand it has limitations due to its high cost, self
discharge, packaging problems etc.
CONCLUSION
