Another battery that need consideration would be the AGM. Compare that along side the gel .
When I installed my solar system, I did quite a bit of reading, and that is where I came up with telling you about using the gel inside the coach. I seen pictures of installations of a battery bank under the seat of the dinette. They claim they don't gas like a flooded cell and that is how they can do it.
Try doing a Google search, or go to some of these web sites for solar power.
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