Traditional batteries which store energy in chemical reactions, a new device stores electricity by assembling ions on the surface & the engineers coated the surface with graphene. A team of engineers at Vanderbilt just built such a device. The Graphene protect the silicon; it also improved the device’s energy density by over two orders of magnitude. That made the silicon super capacitor capable of storing more energy.

26 October 2013 -Source: http://www.gizmodo.com.au/2013/10/this-graphene-coated-silicon-power-cell-signals-a-battery-free-future/

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