Battery Inverter

A battery inverter is a dedicated device that manages the charging and discharging of a battery storage system. It converts AC electricity to DC for battery charging and then converts the stored DC back to AC when the battery discharges to power your home.

Battery inverters are used in AC-coupled solar-plus-storage systems, where the solar array has its own separate solar inverter. This configuration is common when adding battery storage to an existing solar system — you keep your existing solar inverter and add a battery with its own inverter. The battery inverter handles the bidirectional power flow: charging the battery from excess solar production or cheap grid power, and discharging to the home during outages or expensive peak-rate periods. Some batteries, like the Tesla Powerwall and Enphase IQ Battery, have the inverter built in, making installation simpler. Stand-alone battery inverters are used with battery banks that don’t include integrated electronics. The key specification to compare is continuous power output (measured in kW), which determines how many appliances the battery can power simultaneously.