(Watch this video for more information)
A battery inverter/charger (a.k.a. backup inverter) can charge a connected battery with utility grid power (Eskom) and the stored energy can be used to power the connected loads when utility grid power is not available. This is a UPS.
Solar panels cannot directly be connected to a battery inverter/charger, but a separate charge controller must be added (DC-Coupling) or a grid-inverter must be added (AC-Coupling) to form a Constructed Hybrid System.