In a home solar-plus-storage system, one or more LG Chem RESU batteries are connected directly to your solar inverter, charging them using direct current (DC) power produced by your solar panels.
The batteries can hold between 7 and 9.8 kilowatt-hours (kWh) of electricity, depending on the size you choose. That corresponds to model # RESU7H for the 7-kWh battery and model # RESU10H for the 9.8-kWh version.
During the day, when the sun is high in the sky, home solar systems produce more electricity than the house needs. That stored solar energy can be used to power the home later in the evening, after the sun sets. It’s also possible to set the battery to retain a certain amount of its stored energy in case of a power failure.
The best solution for interfacing a RESU ESS with solar panels and the utility grid. The SolarEdge StorEdge is a single inverter for solar panel grid-tie applications that also manages DC battery backup storage power. It includes the hardware required to provide automatic backup power to backed-up loads in case of grid interruption. The SolarEdge also includes all of the interfaces needed for DC battery connection.
LG Chem’s warranty promises that its RESU batteries will maintain at least 60% of their initial rated energy storage capacity after 10 years OR before the battery has been used to provide 22.4 megawatt-hours (MWh) of electricity.
That distinction is important, because if you’re fully charging and discharging the battery daily, you’ll run through that amount of MWh sooner than 10 years. To spread 22.4 MWh over 10 years, you’d have to ensure the batteries discharge an average of only 6.14 kilowatt-hours (kWh) per day, which is 62% of their capacity.
This should be fine for most people, as daily cycling of the battery isn’t necessarily the plan. Talk to our experts to find out whether you should expect to use more than 6.14 kWh of battery storage per day.