How ultracapacitors work (and why they fall short)

Hang around the energy storage crowd long enough, and you'll hear chatter about ultracapacitors. Tesla Motors chief executive Elon Musk has said he believes capacitors will even "supercede" batteries.

What is it that makes ultracapacitors such a promising technology? And if ultracapacitors are so great, why have they lost out to batteries, so far, as the energy storage device of choice for applications like electric cars and the power grid?

Put simply, ultracapacitors are some of the best devices around for delivering a quick surge of power. Because an ultracapacitor stores energy in an electric field, rather than in a chemical reaction, it can survive hundreds of thousands more charge and discharge cycles than a battery can.

A more thorough answer, however, looks at how ultracapacitors compare to capacitors and batteries. From there we'll walk through some of the inherent strengths and weaknesses of ultracaps, how they can enhance (rather than compete with) batteries, and what the opportunities are to advance ultracapacitor technology.

http://gigaom.com/cleantech/how-ultracapacitors-work-and-why-they-fall-short/

in Capacitors

Students at the Stevens Institute of Technology in Hoboken, New Jersey have created a supercapacitor - used for storing energy - that replaces activated carbon with biochar electrodes. The new substance is half as expensive, it's made from a by-product of biofuel, and it's much easier to produce than activated carbon. This breakthrough could bring the cost of supercapacitors down drastically while making it easier to store renewable energy for when it is needed.

http://inhabitat.com/new-supercapacitor-made-with-biofuel-by-product-is-cheaper-greener/

in Capacitors