adding to coach battery capacity

brianokeefe wrote:
I can try and find 6V batteries of the size that will fit in my limited compartment space. It just fits the current 12V deep cycle one. I could get 2 larger (dimension) in which one fits into the battery compartment and one I could put in the closet and connect them in parallel. If I did that by connecting both to the inverter, thus they'd only charge or do nothing than run the 12V coach system, if the inverter isn't on. Is that a solution? Sort of loath to replace the inverter because 1) it was expensive and 2) it will run a toaster, coffee maker and even a toaster oven.

Two 12V batteries in parallel, each in a differnet compartment with a gap between them is a very bad scenario. Two 12V batteries must be butted against each other with minimal length cabling between them. Even then it's not ideal as previously explained. You will do so much better separating two 6V batteries hooked up in series.