Abstract
Super capacitors also known as Electric double-layer capacitors, or electrochemical double layer capacitors (EDLCs), or ultracapacitors, are electrochemical capacitors that have an unusually high energy density when compared to common capacitors, typically on the order of thousands of times greater than a high capacity electrolytic capacitor. For instance, a typical electrolytic capacitor will have a capacitance in the range of tens of millifarads. The same size super capacitor would have a capacitance of several farads, an improvement of about two or three orders of magnitude in capacitance but usually at a lower working voltage. Larger, commercial electric doublelayer capacitors have capacities as high as 5,000farads.
Super capacitor technology is based the electric double layer phenomenon that has been understood for over a hundred years. However, it has only been exploited by commercial applications for about ten years. As in a conventional capacitor, in an ultracapacitor two conductors and a dielectric generate an electric field where energy is stored. The double layer is created at a solid electrode-solution interface - it is, then, essentially a charge separation that occurs at the interface between the solid and the electrolyte. Two charge layers are formed, with an excess of electrons on one side and an excess of positive ions on the other side. The polar molecules that reside in between form the dielectric. In most ultracapacitors, the electrode is carbon combined with an electrolyte.
Consumer Electronics
Super capacitors can be used in PC Cards, flash photography devices in digital cameras, flashlights, portable media players, solar power calculator, electronic toy, internet equipments and in automated meter reading, particularly where extremely fast charging is desirable.
Fuel Cell Vehicles
In the future the combustion engine mechanical energy obtained from the fuel combustion could be replaced electrical engine supplied by electricity produced by a fuel cell. The promise of fuel cell technology has had a recent resurgence due to new advancements not in fuel cells, but in the double-layer capacitors. Indeed, high power energy storage is required in all types of fuel cell applications and double-layer capacitors are ideally suited to provide it. These improvements open up opportunities for the development of new power train and subsystem architectures utilizing both double-layer capacitors and fuel cells which can improve performance, efficiency, and cleanliness in electric and hybrid vehicle technology.
Introduction
This paper offers a concise review on the use of a super capacitor in various energy storage applications. Super capacitor is also known as Electric/electrochemical double layer capacitor (EDLC) is a unique electrical storage device, which can store much more energy than conventional capacitors and offer much higher power density than batteries. Electric double-layer capacitor would have a capacitance of several farads, an improvement of about two or three orders of magnitude in capacitance, but usually at a lower working voltage.
Conclusion
In this paper the use of super capacitor for various energy storage applications is described. They would have a capacitance of several farads, an improvement of about two or three orders of magnitude in capacitance, but usually at a lower working voltage. The specific Power of the super capacitors and its lifetime (1 million of Cycles) is very high. These peculiarities make it very attractive for various energy storage applications and the startup of the automobiles etc.
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