Circuit assembly

The circuit device has battery unit (10) that is composed of several battery cells or cell strands (11-18) that are arranged in series and are switched in parallel manner. A device (20) for galvanic disconnection is provided with switches (21-28) that are arranged at respective output of battery cells or cell strands. The controllers (30-32) are configured to monitor charging state of battery unit, and to release or disrupt the connection of battery unit to load.