The Growatt 3kW AC Coupled Inverter + x2 LV 3.3kWh Battery. This AC-coupled storage can offer a number of advantages such as flexibility of installation and also future upgrades or changes to either the solar or storage system. With Growatt AC-coupled storage, system upgrades or changes are more flexible and can be realised at lower future cost and risk. The Growatt 3.3 kWh Batteries can be added on to make a system with a maximum of 6 batteries, giving a maximum of 19.8 kWh. Add EXTRA 3.3kWh batteries (max 5 batteries) to meet your storage configuration.