I'm looking for some advice for marine batteries that is specific to the winter temperatures in the South central region. I have three batteries in my boat. Two flooded for starters and one AGM for house. Last winter all three were flood types and I just left them in the boat over the winter stored outside. They seemed to be fine this year after giving them a fresh charge in spring. I ended up replacing the house battery with an AGM this season.
What's the best practice for battery storage in our area? Do you guys bring them in the garage? Trickle charge? The flooded ones are cheap but I would like to do what I can to make the AGM last a while.