DutchmenSport wrote:
I can't respond on the type of battery, but I think to use the battery from the trailer in the canoe is NOT a very wise thing to do. If you tip the canoe, there goes your battery. at best get a second battery for the canoe and leave the one alone in the camper. It would be bad enough to have your battery at the bottom of a lake, it would be just as bad to have your trailer battery at the bottom of a lake!
We rented a canoe once, and lost everything at the bottom of a river! Camera, clothes, food, drinks, everything with it tipped on us. Our kids said they'd never go in another canoe again.
Fast forward. Kids pretty much grown, no longer camping with us, and we purchase our own canoe. BUT! I got outriggers! They actually cost more than the canoe. We've NEVER tipped the canoe. It's so stable, I can stand and fish!
So, unless you have something like this, you really need a separate battery for the canoe. It will tip over ... sooner or later!

Maybe I should have been more specific. In addition to using the RV we also float and camp out of the canoe with a tent. I want a lightweight battery to use on the trolling motor and also use to charge phones and use the fillet knife when tent camping. Also, everything is in water proof bags or tote and they float so when you tip over (it happens but not often) everything floats. You just have to gather it up and go again. The battery is strapped into the canoe so it does not fall out.