Maintaining RV batteries

Batteries like to be stored in cold areas WHEN they are fully charged. A small [6 or 10 amp] battery charger with an ammeter should be enough. The charge rate may start at full charging with a weak battery, and after several[?] hours the ammeter will drop down to near zero. A sign it is fully charged. Disconnect the charger. Wait a day and measure the batteries' voltage. Should be 12.6 or so. Remeasure the voltage every month and if you notice a drop in voltage from the 12.6, recharge the battery. It may go for 6 months without the need for recharging. This only applies IF the batteries are isolated!!!!