Bacteria oxidize the organic matter and, in the process, produce electrons that run from the anode to the cathode within the fuel cell, creating an electrical current.

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Many companies are working on coming up with better materials for the cathode or the anode in order to increase the energy density of the battery cell.

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There are several sorts of fuel cell, but all consist of two electrodes (an anode and a cathode) separated by a material called an electrolyte.

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