I replaced the deep cycle battery that was on my 28' travel trailer, it was about the size of a car battery. I went with one about 3 times the size, alot more cold cranking amps, cause I wanted to be able to stay somewhere for a full week without worrying about losing juice. so the battery that I replaced is gonna be used with my troller....I looked at a couple small horsepower gas jobs, but decided to go w/ the troller, because my canoe is double ended and the troller was alot lighter to be hanging off the side.