Paper-thin, flexible, biodegradable battery

... a new material that eliminates the need for a multilayer battery. They grew carbon nanotubes on a silicon substrate and impregnated the gaps between the tubes with cellulose—that's right, plain old paper ... By putting two sheets of paper together with the cellulose side facing inwards [tubules sticking out as electrodes] (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.