We recommend that the batteries be placed indoors, especially if the system is used all year round. It is also possible to install outside or under the cottage in a place where the sun does not shine, as the operation of the battery is also affected by the operating temperature. The AGM battery has a very long life, many times the service life of a standard Freetime battery, but high temperatures significantly reduce battery life. So a steady cool temperature is best.
Ensure that the batteries are sufficiently charged during the winter.