Battery Management System for a High-Voltage Battery of a Motor Vehicle, High-Voltage Battery, and Motor Vehicle

Abstract

A battery management system for a high-voltage battery of a motor vehicle monitors battery cells of the high-voltage battery. The battery management system can be arranged in a battery housing of the high-voltage battery and has an electronic circuit which is arranged on a circuit carrier and has a processor and a communication interface for communication with at least one vehicle-side unit external to the high-voltage battery. The electronic circuit has at least one pressure sensor, which is designed to detect pressure signals in the battery housing and transmit same to the processor. The processor is designed to detect, on the basis of the transmitted pressure signals, a thermal runaway of at least one battery cell of the high-voltage battery, to generate a signal in the event that a thermal runaway is detected, and to provide the signal of the communication interface for transmission to the unit.

Claims

1.-8. (canceled)

9. A system for a high-voltage battery of a motor vehicle for monitoring battery cells of the high-voltage battery, comprising: a battery management system arrangeable in a battery housing of the high-voltage battery, the battery management system comprising an electronic circuit, arranged on a circuit carrier, with a processor and with a communication interface for communicating with at least one in-vehicle, high-voltage-battery-external device, wherein the electronic circuit additionally has at least one pressure sensor designed to capture pressure signals in the battery housing and to convey said pressure signals to the processor, and the processor is configured to: take the conveyed pressure signals as a basis for detecting a thermal runaway of at least one battery cell of the high-voltage battery, generate a signal on detection of the thermal runaway, and provide the signal to the communication interface for conveyance to the device.

10. The system according to claim 9, wherein the at least one pressure sensor is an absolute pressure sensor.

11. The system according to claim 9, wherein the processor is configured to take the pressure signals as a basis for determining a rate of pressure change and to detect the thermal runaway if a value of the rate of pressure change exceeds a predetermined threshold value.

12. The system according to claim 9, wherein the processor is configured to generate a warning signal for a vehicle occupant of the motor vehicle as the signal on detection of the thermal runaway and to provide said warning signal to the communication interface for conveyance to the device in the form of a warning device.

13. The system according to claim 9, wherein the battery management system has a housing in which the circuit carrier is arranged, and the housing has at least one pressure compensation element for a pressure compensation between an interior of the housing of the battery management system and an interior of the battery housing.

14. A high-voltage battery for a motor vehicle, comprising: a plurality of interconnected battery cells; a battery housing; and a battery management system according to claim 9, wherein the battery cells and the battery management system are arranged in the battery housing.

15. A motor vehicle comprising a high-voltage battery according to claim 14.

16. The motor vehicle according to claim 15, further comprising: an in-vehicle, high-voltage-battery-external, warning device for outputting a warning signal for a vehicle occupant of the motor vehicle on detection of the thermal runaway.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0020] The single FIGURE shows a schematic depiction of an embodiment of a motor vehicle according to the invention.

DETAILED DESCRIPTION OF THE DRAWING

[0021] The FIGURE shows a schematic depiction of a motor vehicle 1, which is in particular in the form of an electrically driven motor vehicle. The motor vehicle 1 comprises a high-voltage battery 2 with a plurality of interconnected battery cells 3 and with a battery management system 4, or battery control unit, for monitoring and controlling the battery cells 3. The battery cells 3 and the battery management system 4 are arranged in a battery housing 5 of the high-voltage battery 2. The battery management system 4 comprises an electronic circuit 6 that is arranged on a circuit carrier 7, or a circuit board, of the battery management system 4. The circuit carrier 7 with the electronic circuit 6 is arranged in a housing 8 of the battery management system 4 in this instance.

[0022] The electronic circuit 6 in this instance has a measurement interface 9, which is electrically connected to the battery cells 3 via measurement lines 10. The measurement lines 10 can be used to convey battery-cell-specific data from the battery cells 3 to a processor 11 of the electronic circuit 6. There may also be provision for signals to be conveyed from the processor 11 to the battery cells 3. The battery-cell-specific data may be sensor data from sensors close to the cells, for example, which the processor 11 can evaluate and which can be taken as a basis for the battery management system 4 to monitor the battery cells 3. The signals conveyed to the battery cells 3 may be signals for cell balancing, for example. The processor 11 is likewise arranged on the circuit carrier 7. The communication between the measurement interface 9 and the processor 11 can take place via conductor tracks 12, for example.

[0023] A cell-internal short in one of the battery cells 3 can result in a thermal runaway of the battery cell 3 occurring. The resultant heat generation in an interior 13 of the battery housing 5 can result in a thermal runaway of all of the battery cells 3, which in turn can result in a fire in the high-voltage battery 2. In order to be able to warn vehicle occupants of the motor vehicle 1 about this destruction of the high-voltage battery 2, the thermal runaway of the battery cell(s) 3 is supposed to be detected. For example, the thermal runaway can be detected on the basis of the sensor data of the sensors of the battery cells 3 that are conveyed via the measurement lines 10. However, it may be that the measurement lines 10 are severed by a gas escaping from the runaway battery cell 3, which means that the sensor data can no longer be transmitted to the processor 11.

[0024] In order to still be able to reliably detect the thermal runaway, the battery management system 4 has at least one pressure sensor 14, which is a component of the electronic circuit 6 and is therefore likewise arranged on the circuit carrier 7 together with the processor 11. The pressure sensor 14 is designed to capture pressure signals describing a pressure in the interior 13 of the battery housing 5 and to convey said pressure signals to the processor 11, for example via a conductor track 12. The pressure sensor 14 is in particular an absolute pressure sensor, which may be in the form of an MEMS component, for example.

[0025] In order to be able to reliably capture the pressure signals in the interior 13 of the battery housing 5, the housing 8 of the battery management system 4 is in non-gastight form. By way of example, the housing 8 can have a pressure compensation element 15 that permits a pressure compensation between the interior 13 of the battery housing 5 and an interior 16 of the housing 8. The pressure compensation element 15 can be a breathable membrane, for example. The processor 11 is designed to take the pressure signals as a basis for detecting the thermal runaway. By way of example, the processor 11 detects the thermal runaway if a rate of pressure change determined on the basis of the pressure signal exceeds a predetermined threshold value.

[0026] The electronic circuit 6 in this instance additionally has a communication interface 17 that can communicate with the motor vehicle 1, in particular with a device 18 of the motor vehicle 1. As soon as the processor 11 has detected the thermal runaway on the basis of the pressure signal conveyed by the pressure sensor 14, it can generate a signal, for example a warning signal, and provide said signal to the communication interface 17. The latter conveys the warning signal to the device 18, which is in the form of a warning device, for example, and which then outputs the warning signal to the vehicle occupants. The warning signal can ask the vehicle occupants to leave the motor vehicle 1, for example. The warning device can have a warning lamp and/or a loudspeaker arranged in a passenger compartment, for example. There may also be provision for the device 18 to be an in-vehicle control unit that itself generates a warning signal for a warning device on receiving the signal generated by the processor 11.

LIST OF REFERENCE SIGNS

[0027] 1 motor vehicle [0028] 2 high-voltage battery [0029] 3 battery cell [0030] 4 battery management system [0031] 5 battery housing [0032] 6 electronic circuit [0033] 7 circuit carrier [0034] 8 housing [0035] 9 measurement interface [0036] 10 measurement lines [0037] 11 processor [0038] 12 conductor track [0039] 13 interior of the battery housing [0040] 14 pressure sensor [0041] 15 pressure compensation element [0042] 16 interior of the circuit carrier housing [0043] 17 communication interface [0044] 18 device