While our trailer was set up well for towing running vehicles, a stranded vehicle was a different story. Having a battery in a trailer can give a point to jump a dead battery off of, and a power source for running a winch. There is a pin that can be utilized in seven-pin trailer wiring harnesses to charge the trailer battery while the trailer is hooked to a tow vehicle. We used an Odyssey PC 1700 battery we purchased at West Coast Batteries and set it inside a Summit Racing aluminum battery box that we bolted down to the floor of the trailer’s front cargo box. We have the lid off the box for picture purposes, but the box is a covered, sturdy unit strong enough for two people to stand on.