Sony Corp presented a bio battery that generates electricity by decomposing glucose using an enzyme at the International Hydrogen & Fuel Cell Expo. When supplied with Coke, it generated power and rotated a fan attached to a motor. (Can see it now, ordering a Coke on the airplane to charge my laptop.) The bio battery decomposes glucose using an enzyme at the negative electrode and generates power by extracting electrons and hydrogen ions from it. Absorbing oxygen in the air at the positive electrode, the battery generates water through a reductive reaction of electrons and hydrogen ions. Sony doubled the battery's output density per unit volume achieved by the previous model, which was announced in August 2007, to 2.5mW/ccl.
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