Designer Jiang Qian has developed a concept charger that utilizes the mechanical energy generated in Chinese balls and converts it into electricity. Roll Charger, as Jiang calls his concept, harnesses energy as the balls are rolled in the palm. The device then converts this rotating motion into electricity, which is then fed into a single AA or AAA battery that fits neatly inside the ball. Since two balls are used to stimulate the acupuncture points, you can charge two batteries at once, which can then be used in a remote or other devices powered by them. A LED is integrated into the device which tells you that the charger is functioning and also alerts the user when the batteries are completely charged.
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