Originally Posted by Yarome
Nope. It's pretty much just that simple. :-) The only thing you really want to watch out for is ensuring that the cable runs are equal in length. The converter/charger with be charging both batteries at the same rate.
AND the positive from the camper goes to the positive of the first battery and the negative from the camper's frame goes to the last battery in the stack to keep the battery usage (charge/discharge) equal.
The wires in between the batteries should be exactly the same length and gauge; as well as the heaviest you can buy to keep the current loss between batteries as low as possible. The OEM wires to the converter and the frame don't matter as they are properly sized for the camper's current draw. The middle graphic implies that the camper wires also need to be equal length, but that is not correct.
As stated before, the only "drawbacks" are weight and cost. They also must be replaced in pairs if a two battery stack (all 4 if a 4 battery stack) when even one goes bad to keep the stack balanced.
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