BATTERY DEVICE FOR A VEHICLE

1 . Battery device ( 10 ) for a vehicle, having a main battery system ( 20 ) with at least two battery units (BS) and an emergency battery system ( 30 ) with at least one battery unit (BS), wherein the main battery system ( 20 ) has more battery units (BS) than the emergency battery system ( 30 ), wherein the main battery system ( 20 ) and the emergency battery system ( 30 ) furthermore have the same nominal voltage and are electrically connected in parallel with one another, and the main battery system ( 20 ) has a main switch ( 22 ) for disconnecting the main battery system ( 20 ) and the emergency battery system ( 30 ) has an emergency switch ( 32 ), separate from the main switch ( 22 ), for disconnecting the emergency battery system ( 30 ).

2 . Battery device ( 10 ) according to claim 1 , characterised in that the emergency battery system ( 30 ) has exactly one battery unit (BS).

3 . Battery device ( 10 ) according to claim 1 , characterised in that the battery units (BS) of the main battery system ( 20 ) and the battery units (BS) of the emergency battery system ( 30 ) are electrically identical or substantially identical.

4 . Battery device ( 10 ) according to claim 1 , characterised in that the main battery system ( 20 ) and the emergency battery system ( 30 ) are arranged in a common battery housing ( 40 ).

5 . Battery device ( 10 ) according to claim 1 , characterised in that the emergency switch is reduced in design in relation to the main switch ( 22 ) at least with regard to one of the following parameters:

electrical load limit

costs

weight

electrical fuse protection.

6 . Battery device ( 10 ) according to claim 1 , characterised in that the emergency battery system ( 30 ) is arranged adjacent or substantially adjacent to a common control module ( 50 ) of the emergency battery system ( 30 ) and of the main battery system ( 20 ), in particular closer than the main battery system ( 20 ).

7 . Battery device ( 10 ) according to claim 1 , characterised in that the main battery system ( 20 ) and the emergency battery system ( 30 ) have a common contact section ( 60 ) for a parallel-connected connection to a consumer.

8 . Battery device ( 10 ) according to claim 1 , characterised in that a common control module ( 50 ) is provided for the main battery system ( 20 ) and the emergency battery system ( 30 ), wherein in particular at least one common additional control module ( 52 ) is provided for the main battery system ( 20 ) and the emergency battery system ( 30 ).

9 . Method for monitoring a battery device ( 10 ) with the features of claim 1 , having the following steps:

detecting a defect in a battery unit (BS),

detecting an assignment of the defective battery unit (BS) to the main battery system ( 20 ) or the emergency battery system ( 30 ),

disconnecting the main battery system ( 20 ) or the emergency battery system ( 30 ) on the basis of the assignment of the defective battery unit (BS).

10 . Method according to claim 9 , characterised in that in the case of an assignment of the defective battery unit (BS) to the main battery system ( 20 ), the power output of the emergency battery system ( 30 ) is limited.

11 . Method according to claim 9 , characterised in that in normal operation of the battery device ( 10 ) the main battery system ( 20 ) and the emergency battery system ( 30 ) are at least at times operated together.