Just buy a spare battery (doesn't need to be expensive, wal-mart would be fine) and make sure it's charged before you take the trailer out. It's not that difficult, a deep cycle marine battery would be the best (the kind you use for tolling motors). Just hook the battery to the winch when you need it, otherwise leave it on the trailer or in the bed of the truck when not in use. make sure you buy a battery boc and secure it to the trailer if you leave it on the trailer.

 

Thanks for the pics 79pacecar. Looks like a slick setup. I'll have to check out the pieces at NAPA and see if I can put a similar setup together cheaper than just mounting a battery. Tnanks again for all the replies.