Biobattery

A bio-battery is an energy storing device that is powered by organic compounds, usually being glucose, such as the glucose in human blood. When enzymes in human bodies break down glucose, several electrons and protons are released. Therefore, by using enzymes to break down glucose, bio-batteries directly receive energy from glucose. These batteries then store this energy for later use. This concept is almost identical to how both plants and many animals obtain energy. Although the batteries are still being tested before being commercially sold, several research teams and engineers are working to further advance the development of these batteries.

Like any cell battery, bio-batteries contain an anode, cathode, separator and electrolyte with each component layered on top of another. Anodes and cathodes are the negative and positive areas on a battery that allow electrons to flow in and out. The anode is located at the top of the battery and the cathode is located at the bottom of the battery. Anodes allow electrons to flow in from outside the battery, whereas cathodes allow current to flow out from the battery.

Between the anode and the cathode lies the electrolyte which contains a separator. The main function of the separator is to keep the cathode and anode separated, to avoid electrical short circuits. This system as a whole, allows for a flow of protons (H+) and electrons (e-) which ultimately generates electricity.

Bio batteries are heavily based on the amount of glucose available. This glucose (sugar) can be provided from nearly anything, including soda, waste materials (such as old papers), or the glucose in living organisms. The decomposition of materials to glucose (if they are not already in the proper stage) is the main step in getting the cycle started. Materials can be converted into glucose through the process of enzymatic hydrolysis. Enzymatic hydrolysis is the process in which cellulose (an insoluble substance) is converted to glucose by the addition of enzymes. Once glucose is present, oxygen and other enzymes can act on it to further produce protons and electrons.

Similar to how human bodies convert food to energy using enzymes, bio-batteries use enzymes to convert glucose into energy. When glucose first enters the battery, it enters through the anode. In the anode the sugar is broken down, producing both electrons and protons.

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Wikipedia