Ultracapacitors bridge the gap between batteries and capacitors. One application is the storage of energy in KERS, or dynamic braking systems (Kinetic Energy Recovery System) in the automotive industry. The challenge in this system is building an energy storage device capable of rapidly storing large amounts of energy. A possible solution is to use an electrical generator which convertsd kinetic energy to electrical energy and then stores it in an ultracapacitor.
Another application is low-power applications where high capacity is not critical, but a high life cycle or quick recharging is important. Applications like this would be photographic flash, MP3 players, static memories (SRAM) which need a low power constant voltage source.
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