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How to use a solar panel without frying a battery when it's done charging? Answered

I am curious to know if i need a component that will stop my homemade solar panel USB charger to stop charging a device when the battery is full. could the solar panels over charge the battery when it's full? Will the unneeded voltage just turn into heat? I also would like to know if I can hook multiple devices that each use 5v and 500MA with a solar panel that puts out 5v and 8 amps without slowing the charging speed. Im sorry if I can't phrase the question right... please try to decipher my description of my problem


I have a very limited knowledge in some areas, and more in others. I don't have access to anything but shop tools, scrap parts, and the internet; and i will have a much better working knowledge buy learning it from experience. If i learn it once by my self even the hard way, I will never forget it. Thank you for your knowledge!

So if I had a 5v and 8 amp solar panel, I could have 2 ports that each supply 2.5v and 4amps? Or would they each supply 5v and 4amps? Thanks! I've done days of research on the net and even built a working charger without a regulator or overcharge protector. I'm thinking of making a solar trickle charger, once I figure out more specifics (with the help of these question! :) )

How could I make something that could stop the battery from receiving charge? Does such a component already exist...?

If you've got 8 amps coming out of the solar panel you have to be careful using it to charge any usb type battery. That is over 16 times what usb is rated at.

I would have a voltage regulator of 5v and .5amp. is it possible to fry a battery by over charging it with the solar panels?

how do I find the load capability of a solar panel?