An expansion battery is added to an existing storage system to increase its capacity. Eight modules are offered, from about 2.5 to 7 kWh, from EcoFlow, Anker, Jackery, Zendure and Lunergy, most of them LiFePO4 with an IP65 or IP66 protection rating.
Anker
Anker
Anker
EcoFlow
Jackery
Lunergy
Zendure
Zendure
An expansion unit cannot work alone: it connects to a main unit from the same range. Compatibility is therefore the first criterion. An EcoFlow STREAM, Anker SOLIX, Jackery SolarVault or Zendure SolarFlow battery does not pair with just any base, and the product page states the target system.
Then compare the capacity added, the weight (from 21 to 44 kg depending on the listing) and the IP rating if the installation is outdoors. Check how many modules your main unit accepts. If you are starting from scratch, a complete pack may be simpler, and our 2-year legal warranty applies. Finally, plan for the cables and connection listed on the product page, and read the specifications before ordering to avoid any incompatibility.
