With the rapid decrease in the size of mobile phone and other Gizmos which keep reducing their size, it become necessary for Scientists to make a really thin battery which will further decrease the size of batteries. Thats what they have done, make it papper thin. If you remember those motorolla Slim phone, battery is the only thing that makes them thinner. Now let us see what this new technology can do to the size of mobile phones. The best thing about this battery is that, it is biodegradable(Now we can say we are doing something to overcome the pollution)and flexible (means you can make it as slim as anything).

By putting two sheets of paper together with the cellulose side facing inwards (and a drop of electrolyte on the paper), a supercapacitor is formed. These supercapacitors retain the flexibility of normal paper, but they have a rating that is comparable to that of standard commercial hardware—a 100g sheet could replace a 1300mAh battery. Because the medium is flexible, the researchers say you could shape batteries of all sizes for very specific use.

Read more at ARS