
The key to the discovery lies in the way in which the algae, Cladophora, produce a unique type of cellulose with a very large surface area (approximately 80 square meters of surface area per gram of material).
By coating this algal cellulose material with a thin layer of a well-known, conductive polymer, called polypyrrole (PPy), the team has “succeeded in producing a battery that weighs almost nothing and that has set new charge-time and capacity records for polymer-cellulose-based [non-metallic] batteries,” according to Gustav Nyström, a doctoral student in nanotechnology and one of the main researchers.
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