Secondary on-board network battery for a secondary on-board network that is redundant to a primary onboard network of a motor vehicle, on-board network system, and motor vehicle

A vehicle electrical system for a motor vehicle, comprising:

• a primary vehicle electrical system with at least one primary vehicle electrical system component and a primary vehicle electrical system battery for supplying the at least one primary vehicle electrical system component;
• and
• a secondary vehicle electrical system which is redundant with respect to the primary vehicle electrical system and comprises:
• a battery cell assembly for providing electrical energy;
• a first connection for electrically connecting the secondary vehicle electrical system battery to at least one secondary vehicle electrical system component;
• a second connection for electrically connecting the secondary vehicle electrical system battery to the primary vehicle electrical system;
• a first switching device between the first connection and a connection point electrically connected to the battery cell assembly;
• a second switching device between the second connection and the connection point;
• and
• a control device which is configured, in order to supply the at least one secondary vehicle electrical system component from the primary vehicle electrical system, to provide a conducting state for both the first and second switching devices in order to permit an energy flow from the second connection to the first connection via the connection point and, in order to keep an overload on the primary vehicle electrical system side away, to provide a blocking state for the second switching device in order to block an energy flow from the second connection to the connection point, wherein
• the secondary vehicle electrical system battery is electrically connected to the at least one secondary vehicle electrical system component via the first connection and is electrically connected to the primary vehicle electrical system via the second connection.

A motor vehicle comprising:

• a vehicle electrical system comprising:
• a primary vehicle electrical system with at least one primary vehicle electrical system component and a primary vehicle electrical system battery for supplying the at least one primary vehicle electrical system component;
• and
• a secondary vehicle electrical system which is redundant with respect to the primary vehicle electrical system and comprises:
• a battery cell assembly for providing electrical energy;
• a first connection for electrically connecting the secondary vehicle electrical system battery to at least one secondary vehicle electrical system component;
• a second connection for electrically connecting the secondary vehicle electrical system battery to the primary vehicle electrical system;
• a first switching device between the first connection and a connection point electrically connected to the battery cell assembly;
• a second switching device between the second connection and the connection point;
• and
• a control device which is configured, in order to supply the at least one secondary vehicle electrical system component from the primary vehicle electrical system, to provide a conducting state for both the first and second switching devices in order to permit an energy flow from the second connection to the first connection via the connection point and, in order to keep an overload on the primary vehicle electrical system side away, to provide a blocking state for the second switching device in order to block an energy flow from the second connection to the connection point, wherein
• the secondary vehicle electrical system battery is electrically connected to the at least one secondary vehicle electrical system component via the first connection and is electrically connected to the primary vehicle electrical system via the second connection.