A bio-battery is a battery where the oxidation of organic matter (typically glucose) is aided by enzymes or is carried out by bacteria. These offer several advantages over the conventional batteries (e.g. Lithium ion batteries, etc.) including, instant recharging, non-flammable & non-toxic fuel, safe storage & distribution, sustainability and environmental friendly process.
In simplest terms, a bio-battery works on breakdown of organic molecule at the anode, with subsequent release of proton and electrons. These particles then complete an oxidation-reduction reaction at the cathode, aided by oxygen to generate water. The flow of electrons through the circuit thus causes generation of electricity. These reactions can be mediated by enzymes and/or carried out by specific microbes (thus making a microbial fuel cell or MFC).
However, the major drawback is that they are still in research and development phase and are at least few years away from the market.
The bio-battery offers the advantage of complete oxidation of the organic molecule and hence are more efficient. In a recent study, a sugar bio-battery (596 Ah/kg) has shown energy density which is an order of magnitude higher than that of Li-ion batteries (42 Ah/kg).
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