Originally Posted by bring_it_on

If weight and size is a concern, and you don't mind spending some more $$ then you may want to consider the relion RB75 which fits most standard aux battery plates on the 5th gen, works with your BMS and has more available juice. Some of the additional cost can be reduced by going for a smaller solar panel as you won't need as much solar replenishment as with an AGM battery that needs to be topped up above 50%. In my setup, I was initially planning to use a Group 34 battery under the hood and a 100-160 Watt solar panel up on the roof rack. The Roof rack is also going to carry a RTT so I was limited on space and had to find a solar panel that would fit. I'm now considering the RB-75 and not mounting a solar panel at all and picking up a slightly used 90 Watt Zamp portable solar panel. That frees up room on the rack for traction boards or fuel.