Before parking the RV for an extended time period, make sure the battery is charged completely. Don't overcharge it as this may boil the water away and cause the plates to overheat, warping them or eroding them and limiting the battery life. Check the water level. If it is low, fill it with only distilled water. Tap water contains minerals that can negatively affect the performance of the battery. A solution such as BatteryMinder can help desulfinate the plates and help maintain the battery.
Check the battery with a hydrometer periodically during storage and recharge as necessary.
If you are going to leave the battery in the RV, disconnect the ground (black) cable after you charge it completely, says Darrel Keyser, a mechanic in Blunt, S.D. If you live in a mild climate, it is probably not a problem to leave the battery in the RV, especially if it is parked indoors. In cold or hot climates, you will probably want to remove the battery and keep it indoors.
If the battery will be subjected to below-freezing or very high temperatures, it's best to remove the battery and store it indoors. Make sure it is completely charged before removal. Store it somewhere that is not subject to extreme temperature changes. Do not store the battery on a floor, especially not a cement floor. Cement floors have been known to drain batteries. Place the battery instead on a wooden pallet, shelf or block of wood. Do not store the battery in a room used for sleeping.
