I acquired a dead solar cellphone charger unit. I did minimal testing of it, and it was totally dead. It has the surface mount components, so I did not go any further. I salvaged the 2.5" X 4" solar cell panel, and tossed the rest of it. In a lighted room, (lights turned on) it puts out just under one volt DC. I imagine it will put out more voltage in sunlight, but I have not tried it, since we have not seen the sun in days. Anyhow, can I connect that panel directly to a common AA rechargable battery? (or maybe I should charge two batrteries at once, in series)? If not, is there a simple circuit I can build, or should I just steal a circuit board from one of them solar yard lights, (which have a much smaller solar panel).

oldschool wrote Some charge controller chip would be in place. Do not use AA, use lipos. What is the short circuit current that panel gives in direct bright sunlight? And the open voltage? Your controller needs to be able to handle that. That also determines if you need a switcher or not to go the battery voltage level.

Can a small photocell panel be connected to a flashlight type rechargable battery?

Oct 11, 2018 42 Replies

Rate this thread:

John S 7 years ago

Well, this is an interesting revelation to me. I had never thought about it in this way before. Thank you for leading me to this understanding.

Vote

gnuarm.deletethisbit 7 years ago

Is that so surprising? When you run a steam engine, the steam leaving the cylinder is cooler than the steam entering. In an internal combustion engine the temperature in the cylinder is higher before the power stroke than after.

Rick C.

Vote

John S 7 years ago

I didn't say it is surprising. I have been using panels without thinking about energy conservation. It won't change my designs, however I have gained some insight into them.

Vote

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required