Virus-Based Batteries

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By pouring a mixture of the harmless, genetically engineered M13 virus and the metal cobalt over stamped silicon film, Angela Belcher and her colleagues created a flexible, microscopic battery that could be cheaply mass produced.

In theory, it could turn virtually any surface -- from large computers to tiny implanted detectors for cancer or heart disease -- into an energy-storing device.
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Belcher and her colleagues created the first virus-powered battery in 2006. Since then they have been refining their viral battery while working to create other novel energy-storing devices that could be woven into fabrics or poured into containers.
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Gram for gram, the virus-based batteries are roughly twice as powerful as traditional chemical batteries, said Belcher, although the battery cells are so small -- about four microns across -- that exact measurements are difficult. It takes about an hour for an M13 battery to form.
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