ShoelaceExpress wrote:
The new TT needed a new battery, so I ended up purchasing two deep-cycle RV/marine batteries to install in parallel.
It's too late now but two 6 V in series is really a better arrangement.
Nothing seriously wrong with what you propose to do and for all intents and purposes the two together can be treated just as one larger battery.
Yes, a disconnect switch would be good. Or just disconnect the negative battery cable.
The only potential problem with a parallel arrangement is: If one battery goes bad or starts getting weak, it will drag the other one down with it.
I suggest that each year when you take them into the garage, you charge each one individually first and check the specific gravity and resting voltage after removing the charger for 24 hours. IF they still seem to match, connect them in parallel again and attach the battery maintainer. It needs to have a capacity of AT LEAST 2 amps and must NOT be just a cheap trickle charger.
