אפר' 04
A charger that could charge any battery (regular AA batteries, or others), without being hooked up to electricity.
The purpose of such an product is for travelers, that carry multiple battery-run devices, and want the ability to charge them on the road.
The charger itself has a large chargable battery (which is a paradox, i know...).
It has to be small enough to be carried in a bag, but its battery has to be strong enough to be able to charge others.
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