Ive seen peolple do this to power a charger. Don't you need at least 10 amps to do that though? It looks like most power supplies have 4 to 7 amps for pc's I have a sweet 500watt modular power supply that I got for free. Very expensive when new. It's one that you only plug in the leads you need so you don't have a mass of wires in your case. Model was Matrix I believe. Can't remember who made it. Never even opened the box. But have used them before and they are very good.