1. What ratings are the batteries? Volts, mAh... anything else. 2. How old? Physical condition. 3. I'm assuming lead acid. Do they have a 'top up' cap on them? I'm sure you can get a standard battery recharger, like for automobiles to charge them up. As for running your equipment off them, you need some kind of DC to AC converter. I have one for my car that hooks up into the lighter socket. It runs off 12v and its rated for 60W continuous. You would need one rated 130W or more depending on what your equipment sucks down, and how much equipment you are hooking up. Oh and one more thing. I hope you are aware of the dangers of messing around with lead acid batteries. 1. If you overcharge them, they can and do explode. 2. If they discharge less than 40% the acid begins eating the lead degrading your battery. 3. Risk of fatal (that means you die) electric shock if you do something stupid. Read up if you don't know.