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convert 12v cordless battery to solar charge Answered

My first post- great site! I'm a complete idiot when it comes to electrical; does anyone out there know of a way to charge a 12v cordless drill battery with a solar panel- the eventual end result being to power a bank of LED lights and can all LED lights be powered with DC, if so how many could I expect to run?


not sure about power. youd need a voltage regulator, such as a 7812 or zener diode, in order to protect the battery.

could he do it with just a diode if it's a nicad?

probably, yes. but id still use a zener diode. they are cheap to buy and easy to install, while protecting the battery

yeah, that too ;) One last time to make sure I get this, let's say you have a 5 volt zener. You put it in series with a ninevolt battery (backwards, reverse biased, how zeners are meant to be used). If you were to take the voltage from the opther side of the zener and ground, would it be 4 volts?

(and yes, LEDs can be powered with DC. They are, in fact, DC devices. If you're using a 12V supply, though, you will need a resistor in series with each LED to protect it. "How many" depends on what voltage you charge your battery to, on the exact model of LED you use, and how you wire them together (series or parallel))

Thanks for the advice guys, like I said the tech stuff is kinda beyond me but my neighbor is a field engineer so I'll pick his brain when he returns from China- I was mostly concerned as to whether I'm on the right track: the actual project will be a solar powered table top with glass mosaic tiles, embedded solar panel and glow in the dark grout.