Battery charger?

Question

If i connect a solar panel to a battery holder full of rechargeable batteries, is there a thing that can shut of electricity to the batteries when they are fully charged? How do commercial solar chargers do it?

Answer 1

For a solar system you need a regulator which has a feedback from the batteries. This refers to a reference voltage and when reached this opens a relay and closes the path to the charger.

There are several chargers using this technology on the market, or you can make your own:

http://www.uoguelph.ca/~antoon/gadgets/s...

Answer 2

Ebay is loaded with them.  I have one listed there myself right now.  They are called Solar Controllers.  Do an ebay search for "Solar Controllers"   They protect the batteries from overcharge, and also prevent the batteries from discharging back through the solar cells when the clouds are in.