Paper-thin Batteries Made from Algae

Imagine wrapping paper that could be a gift in and of itself because it lights up with words like "Happy Birthday." That is one potential application of a new biodegradable battery made of cellulose, the stuff of paper.

The key to this new battery turned out to be green algae known as Cladophora. This algae makes an unusual kind of cellulose typified by a very large surface area, 100 times that of the cellulose found in paper. This allowed researchers to dramatically increase the amount of conducting polymer available for use in the new device, enabling it to better recharge, hold and discharge electricity.