State of charge

State of charge, or SOC, is the current charge level of a battery, usually shown as a percentage. In a home battery system, the displayed SOC helps show how much of the battery's managed operating range is charged at that moment. Battery apps, inverter portals and commissioning documents may use SOC when showing live system data, setting battery reserve levels, scheduling charging or limiting discharge. It should be read alongside usable capacity, battery reserve, charge power and discharge limits rather than as a promise that the whole nameplate capacity is available. The percentage depends on how the product measures, synchronises and limits the battery, so it should not be treated as a warranty measure or a guarantee of backup runtime.