Using your EcoFlow Delta Max Portable Smart Additional Battery is easy. First, plug it into your DELTA Max portable power station. You can add up to two units to increase the total capacity. When it's time to recharge, you can use various sources like solar panels, AC outlets, your vehicle, or the Smart Generator. The battery will charge together with the DELTA Max. In an emergency, you can even recharge it directly from the Smart Generator without the DELTA Max. To keep track of the battery's status, look at the LCD screen on the battery or use the EcoFlow app. Remember to store the battery in a cool and dry place. Avoid exposing it to extreme temperatures or moisture. If you're not using the battery for a long time, charge it to about 50% and then store it. This will help keep the battery in good condition over time.