I've been doing this since 2004, with multiple RVs. We are in FL, and I leave the A/C on, set to about 78F. This keeps the temps lower inside, and removes the humidity. Both will destroy the interior of an RV.
Furthermore, most RVs come with a smart charger, with multiple stages of charging. Letting the charger do its job is the best thing you can do for your batteries. Sulfation occurs when a battery is deprived of a full charge, it builds up and remains on battery plates. And a trickle charger allows the battery fluid to stratify, also causing damage if used for long periods. Batteries either need mechanical movement (i.e. in a vehicle), or periodic fast (bulk) charging to mix the fluid.
I have a solar setup at home, and I've learned a lot over the years on how to extend the life of my batteries.