This is kinda neat:

CrunchGear ป Archive ป Panasonic presents electric bike recharging its battery via the braking system

The bike’s main feature is a braking system that can recharge a 10Ah Li-ion secondary battery, which weighs 2.5kg, has a rated voltage of 26 V and is located next to the rear wheel. Every time the owner brakes, a mini motor mounted on the front wheel generates power.
日本語が読めますか?
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