Paper-Thin Batteries Made from Algae

Scientists worldwide are striving to develop thin, flexible, lightweight, inexpensive, environmentally friendly batteries made entirely from nonmetal parts. Among the most promising materials for these batteries are conducting polymers. However, until now these have impractical for use in batteries — for instance, their ability to hold a charge often degrades over use. The key to this new battery turned out to be an often bothersome green algae known as Cladophora. Rotting heaps of this hairlike freshwater plant throughout the world can lead to unsightly, foul-smelling beaches. 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