Crank up power generator or flashlight are not something new in the market in the past decade. But wind up battery will definitely become the next green energy idea as it utilize conventional but working energy idea for convenience and easy to use system.

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If you have been thinking of other solution rather than those  rechargeable lithium-ion batteries, this wind-up battery concept would pretty similar to those old days when cars and radios are powered by hand-crank  system.

[ Source: Yanko Design ]