Originally Posted by
IamJEEP
I researched a bit online and according to a couple of RV forums, 12g wire at 10amps of charge is all you need for a trailer battery. So I would say you can use the trailer 7 wire to charge you trailer battery with no issues.
Sal, I agree that a deep cycle would be the ideal battery here. Trickle charge is the way to go, but I think you would need a battery monitor to stop charging when full.