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Battery capacity anxiety may soon be a relic of the past, at least for small electronics. Chinese consumer electronics manufacturer Oppo has designed a lightweight tracking device that can transmit information like location and temperature, while collecting what little power it needs from ambient energy sources like radio waves, light, and heat, so it never runs out of power. The technology, which Oppo aims to commercialize within the next year, could someday be applied to other small devices.

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