Wiring batteries in parallel.

[Dieseltech910]

So I just bought a new to me boat over the weekend. It’s an 81 14’ Lund that’s been converted to have a console and front/rear decks. The only issue I’m having is with just me in the boat it likes to favor the side the console is on when I’m driving the boat. It has 2 deep cycle batteries one in front and one rear. I was thinking of moving the batteries to the rear opposite of the console to add some counter weight. I’d also be wiring the batteries in parallel to give some increased capacity for running the trolling motor. Any thoughts on this? Any other way I could add some counter weight to balance the boat when it’s just myself using it?. Thanks

 

[H20Rat]

Conventional wisdom says that batteries have to be identical to be wired in parallel, but I can tell you that I've done non-identical batteries for many, many years in my RV. I have mix and matched various group sizes depending on where they fit, and I get great performance with no issues. I would absolutely not mix and match battery chemistries though, that is a recipe for disaster. (and a potential fire)


So with that said, your engine isn't going to be able to recharge that battery bank. It has maybe 5 or 10 amps max of charging current. You might want to keep them split, and if you need additional capacity, add a second battery to the trolling bank. Keep a small starting battery dedicated to the engine.

 

[The Force power]

So I just bought a new to me boat over the weekend. It’s an 81 14’ Lund that’s been converted to have a console and front/rear decks. The only issue I’m having is with just me in the boat it likes to favor the side the console is on when I’m driving the boat. It has 2 deep cycle batteries one in front and one rear. I was thinking of moving the batteries to the rear opposite of the console to add some counter weight. I’d also be wiring the batteries in parallel to give some increased capacity for running the trolling motor. Any thoughts on this? Any other way I could add some counter weight to balance the boat when it’s just myself using it?. Thanks

Depending on the battery seize, I tried my two 31C seize in the back (15' runabout) and it was sitting waay too low (too heavy) so I moved one of the to the center under the back bench (that was as far as I could come forward) that solved it for me.
but every boat is different

 

[Lowlysubaruguy]

The biggest factor is the quality and size of the battery cables between them and there supply and consumers. I mentioned quality a larger sized wire does not mean a better wire in todays times any way 20 years ago that was not the case I see a lot of really poor quality wires they corrode internally and you cant see there condition. Same as above I have ran a variety of different batteries in parallel with no issues at least no issues that I’d blame on there routing. Batteries in boats here take a physical beating which is probably harder on them than almost anything. Placing one up front where the bows hammering on big waves is less desirable in my book than placing them more rearward. But our local River is pretty rough. This may not be a factor for most.