The libbi system can be installed with optional “blackout back-up".
This means that in the event of a power outage, libbi will provide the electricity it’s stored to a dedicated circuit or socket that’s connected to the libbi back-up output. Any connected solar will still charge your libbi in a power cut.
However, this is not an uninterrupted power supply, as UK regulations stipulate that the inverter must stop momentarily (around 5 seconds) to enable the connection to the grid supplier to be lost.