The photovoltaic system and energy storage system are relatively independent, and can be rear-installed for energy storage, making it convenient to transform the existing photovoltaic system. Photovoltaic inverters and energy storage converters are available in different brands.

Photovoltaic DC directly charges the battery (or through a DC/DC conversion), and when discharged, the battery DC power is supplied by a primary inverter to supply the load. Fewer conversions often result in higher overall efficiency.

A single device integrates functions such as photovoltaic inverter, energy storage and current conversion, and on-grid switching, saving space and installation. It can be used efficiently to charge batteries like DC coupling solutions, and can also be compatible with AC coupling (such as AC input of existing photovoltaic inverters).