Researchers at the University of Illinois at Urbana-Champaign have developed a super-dense battery that measures only a few millimeters, but can both store and release a lot of power, resolving a problem that has long plagued consumers and electronics manufacturers. Capacitors can release power very quickly but can't store much. Fuel cells and batteries can store power but release it slowly.
Source: http://www.technewsworld.com/rsstory/77832.html
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