Mr. Buzz is a lightweight solar power battery charger in a cup that uses flexible PowerFilm solar panels to charge a 2400mA battery pack.
This DIY article will teach you how to make a small solar panel that can charge two AA rechargeable batteries or power small DC electronic devices.
It’s not difficult to recondition your old battery, although it takes some skill to perfect the process. While the techniques needed to revive a battery are simple, you don’t need to be a rocket scientist to get the job done.
It would be nice to be able to charge your batteries charge without using any conventional electrical chargers. Well, Knut Karlsen did just that. His homemade solar batteries are made out of normal rechargeable batteries, with built-in solar cells. All you need to do is to leave the batteries under the sun, and they will slowly regain energy.