We recommend keeping the battery power above 20% when using or storing the power station regularly. 2. A fully charged battery can last for several months. However, please recharge it every 3 months to keep the battery power above 50% if you don't use it. Please make sure you charge and store your power station within an ambient temperature of 0-40℃ (32-104°F), and charge the unit within an ambient temperature of -10-40℃ (14-104°F).