BATTERY ARRANGEMENT AND METHOD FOR FIGHTING A BATTERY FIRE AND MOTOR VEHICLE

Abstract

A battery arrangement for a motor vehicle for fighting a battery fire. The battery arrangement includes a battery having at least one battery cell, which is arranged in a battery housing. A charging device is designed to provide electrical energy to the at least one battery cell when connected to a motor vehicle-external energy supply system. Furthermore, a detection device is formed for detecting a predetermined heating state of the battery, which indicates that a battery fire is present or at least imminent. The charging device also includes an extinguishing agent supply unit for fighting fires. The extinguishing agent supply unit is designed, when connected to a motor vehicle-external extinguishing agent reservoir and when the predetermined heating state is present, to provide a predetermined extinguishing agent for supply into the battery housing.

Claims

1. A battery arrangement for a motor vehicle for fighting a battery fire, comprising a battery having at least one battery cell which is arranged in a battery housing, a charging device which is designed to provide electrical energy to the at least one battery cell when connected to a motor vehicle-external energy supply system, and a detection device for detecting a predetermined heating state of the battery, which indicates that a battery fire is present or at least imminent, wherein the charging device comprises an extinguishing agent supply unit, wherein the extinguishing agent supply unit is designed, when connected to a motor vehicle-external extinguishing agent reservoir and when the predetermined heating state is present, to provide a specified extinguishing agent for supply into the battery housing.

2. The battery arrangement according to claim 1, wherein the charging device for coupling to the motor vehicle-external energy supply system comprises a charging connection and the extinguishing agent supply unit for coupling to the motor vehicle-external extinguishing agent reservoir comprises an extinguishing agent supply connection, wherein the charging connection and the extinguishing agent supply connection form a common connection element of the charging device.

3. The battery assembly according to claim 1, wherein the charging device comprises a locking element having a locking mechanism for allowing and/or preventing access to the charging device.

4. The battery arrangement according to claim 1, wherein the extinguishing agent supply unit comprises a valve element which is designed to adjust a mass flow of the extinguishing agent provided depending on the detection of the predetermined heating state.

5. The battery arrangement according to claim 1, wherein the detection device for detecting the predetermined heating state comprises at least one temperature sensor and/or a pressure sensor and/or a gas sensor and/or a fracture sensor.

6. The battery arrangement according to claim 1, wherein the battery housing has an extinguishing agent outlet element for discharging the extinguishing agent from the battery housing.

7. The battery arrangement according to claim 1, wherein the charging device comprises an extinguishing agent discharge unit which is designed to discharge the supplied extinguishing agent from the battery housing to the waste water reservoir when connected to a motor vehicle-external waste water reservoir.

8. A method for fighting a battery fire of a battery arrangement for a motor vehicle, wherein the battery arrangement comprises a battery having at least one battery cell, which is arranged in a battery housing, wherein a charging device of the battery arrangement is connected to a motor vehicle-external energy supply system to provide electrical energy to the at least one battery cell, and a detection device of the battery arrangement is used to check whether a predetermined heating state is present for the battery, which indicates that a battery fire is present or at least imminent, characterized in that the charging device comprises an extinguishing agent supply unit, and by means of the extinguishing agent supply unit, when connected to a motor vehicle-external extinguishing agent reservoir and when the predetermined heating state is present, a predetermined extinguishing agent for supply into the battery housing is provided.

9. A motor vehicle having a battery arrangement according to claim 1.

10. A motor vehicle according to claim 9 wherein the charging device comprises a locking element having a locking mechanism for allowing and/or preventing access to the charging device, wherein the locking element is designed as a charging connection flap of the motor vehicle, by which the charging connection of the charging device and the extinguishing agent supply connection of the extinguishing agent supply unit can be covered from the outside.

11. The battery assembly according to claim 2, wherein the charging device comprises a locking element having a locking mechanism for allowing and/or preventing access to the charging device.

12. The battery arrangement according to claim 2, wherein the extinguishing agent supply unit comprises a valve element which is designed to adjust a mass flow of the extinguishing agent provided depending on the detection of the predetermined heating state.

13. The battery arrangement according to claim 3, wherein the extinguishing agent supply unit comprises a valve element which is designed to adjust a mass flow of the extinguishing agent provided depending on the detection of the predetermined heating state.

14. The battery arrangement according to claim 2, wherein the detection device for detecting the predetermined heating state comprises at least one temperature sensor and/or a pressure sensor and/or a gas sensor and/or a fracture sensor.

15. The battery arrangement according to claim 3, wherein the detection device for detecting the predetermined heating state comprises at least one temperature sensor and/or a pressure sensor and/or a gas sensor and/or a fracture sensor.

16. The battery arrangement according to claim 4, wherein the detection device for detecting the predetermined heating state comprises at least one temperature sensor and/or a pressure sensor and/or a gas sensor and/or a fracture sensor.

17. The battery arrangement according to claim 2, wherein the battery housing has an extinguishing agent outlet element for discharging the extinguishing agent from the battery housing.

18. The battery arrangement according to claim 3, wherein the battery housing has an extinguishing agent outlet element for discharging the extinguishing agent from the battery housing.

19. The battery arrangement according to claim 4, wherein the battery housing has an extinguishing agent outlet element for discharging the extinguishing agent from the battery housing.

20. The battery arrangement according to claim 5, wherein the battery housing has an extinguishing agent outlet element for discharging the extinguishing agent from the battery housing.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0039] Exemplary embodiments of the invention are described hereinafter. In the figures:

[0040] FIG. 1 shows a schematic representation of a motor vehicle having a battery arrangement for fighting a battery fire;

[0041] FIG. 2 shows a schematic representation of a charging device of the battery arrangement according to a first exemplary embodiment; and

[0042] FIG. 3 shows a schematic representation of a charging device of the battery arrangement according to a second exemplary embodiment.

DETAILED DESCRIPTION

[0043] The exemplary embodiments explained hereinafter are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention to be considered independently of one another, which each also refine the invention independently of one another and are thus also to be considered to be part of the invention individually or in a combination other than that shown. Therefore, the disclosure is also intended to comprise combinations of the features of the embodiments other than those represented. Furthermore, the described embodiments can also be supplemented by further ones of the already described features of the invention.

[0044] In the figures, the same reference numerals respectively designate elements that have the same function.

[0045] FIG. 1 shows a motor vehicle from a bird's eye perspective in a schematic sectional view. The motor vehicle 1 has a battery arrangement 10 which is designed to fight a battery fire. The battery arrangement 10 comprises a battery 11 having at least one battery cell 12, which is arranged in a battery housing 13. In FIG. 1, the battery 11 is embodied, for example, as a drive battery or high-voltage battery (HV storage device) for operating an electric drive of the motor vehicle 1. The motor vehicle can thus be an electric vehicle or a hybrid vehicle. The battery 11 in the present example comprises three battery cells 12. Of course, more or fewer such battery cells can also be provided to form the battery 11.

[0046] To form the battery 11, the battery cells 12 can, for example, be electrically connected to one another in a suitable manner (not shown in FIG. 1). The battery cells 12 are so-called electrochemical or galvanic cells. In the present case, the battery cells 12 are lithium-ion cells, for example. The battery cells 12 are designed as accumulator cells or secondary batteries. That is, the battery cells 12 can be both charged and discharged.

[0047] In order to be able to charge the battery 11, i.e., the battery cells 12 for the electrical energy supply, i.e., to be able to supply it with electrical energy, the battery arrangement 10 according to FIG. 1 comprises a charging device 20. The charging device 20 is designed to be coupled to a motor vehicle-external energy supply system 40. The motor vehicle-external energy supply system 40 can be, for example, a charging infrastructure or charging station or, for example, a home power connection. In the coupled or connected state, electrical energy can be provided or transferred to the battery cells 12 of the battery 11 by the motor vehicle-external energy supply system. In order to be able to couple the energy supply system 40 to the battery arrangement, the charging device 20 comprises, for example, a charging connection 22a (not shown in FIG. 1) (see FIGS. 2 and 3) and an electrical line element 22b. The line element 22b can be connected or installed for electrical contacting or connection between the respective battery cell 12 and the charging connection 22a.

[0048] Overheating can occur under certain conditions, for example if one of the respective battery cells 12 is defective. The overheating can occur both in the charging or discharging mode of the battery 11, but also in the idle state of the battery 11. In the present case, overheating means that the respective battery cell 12 thermally runs away. That is, the temperature of the battery cell 12 reaches or exceeds a predetermined temperature limiting value, so that the battery cell 12 undergoes an unstoppable and exothermic chemical reaction. A large part of the electrochemical energy stored in the battery cell can be released in the form of thermal energy. The release of thermal energy can cause a battery fire. The temperature limiting value and the amount of energy released as well as the reaction speed depend, for example, on a technology of the respective battery cell 12. With a lithium-ion battery cell, for example, the temperature limiting value is approximately 80 to 85 degrees Celsius. If the temperature of a lithium-ion cell exceeds this limiting value, it releases approximately 60 percent of the stored electrical energy in the form of thermal energy within a few milliseconds.

[0049] In order to be able to detect or establish the presence or at least the imminence of a battery fire, the battery arrangement 10 in the present case comprises a detection device 30. The detection device 30 is designed to determine a predetermined heating state Z of the battery 11 or its battery cells 12. In the present case, heating state Z means, for example, exceeding the specified temperature limiting value, i.e., the presence of thermal runaway. For this purpose, the detection device 30 comprises a control unit 31a and a sensor unit 31b. According to FIG. 1, the sensor unit 31b is arranged in the battery housing 13 of the battery 11. Here, the sensor unit 31b can comprise, for example, one or more temperature sensors to monitor the temperature of the battery cells 12. The temperature data or sensor data acquired by means of the temperature sensor can be evaluated by means of the control unit 31a. The control unit 31a can thus check, for example, whether the temperature of the respective battery cell 12 according to the temperature data exceeds the predetermined temperature limiting value, which allows conclusions to be drawn about the presence of the heating state Z. The control unit 31a of the detection device 30 can be provided by a central on-board computer of the motor vehicle 1 or a battery management system of the battery 11, for example.

[0050] In order to be able to fight the battery fire, for example, to be able to extinguish it, when it is determined that the heating state Z is present, the detection device can, for example, send an emergency call signal to alert the fire department. For this purpose, the detection device 30 can have a corresponding communication unit, for example a radio module, such as a mobile radio module.

[0051] In order to avoid personal injury and/or property damage in case of fire, the battery arrangement, as shown in FIG. 1, can provide another firefighting measure. For this purpose, the charging device 20 according to FIG. 1 additionally comprises an extinguishing agent supply unit 23. The extinguishing agent supply unit is designed to be coupled to a motor vehicle-external extinguishing agent reservoir 50. A desired extinguishing agent that is suitable for extinguishing the battery fire can be temporarily stored or made available in the extinguishing agent reservoir. Water, for example, can be used as an extinguishing agent. The extinguishing agent reservoir 50 is shown here, for example, as a water tank. Alternatively, the extinguishing agent reservoir 50 can also be implemented as a house water connection or city water connection, for example. In the connected or coupled state of the extinguishing agent supply unit 23 with the extinguishing agent reservoir 50, a predetermined extinguishing agent can be made available or provided by the extinguishing agent reservoir 50. As soon as the detection device 30 additionally confirms the presence of the heating state Z for the battery 11 or at least one of the battery cells 12, the extinguishing agent can be introduced or supplied into the battery housing 13 via the extinguishing agent supply unit.

[0052] For the fluidic connection of the extinguishing agent supply unit 23 to the battery housing 13, the extinguishing agent supply unit 23 comprises an extinguishing agent supply connection 23a (not shown in FIG. 1) and a fluidic line element 23b. As shown in FIG. 1, the fluidic line element 23b is installed for the fluidic connection between the battery housing 13 and the extinguishing agent supply connection 23a.

[0053] In order to provide the extinguishing agent only when required, i.e., only when the heating state Z is present, the extinguishing agent supply unit 23 comprises a valve element 24, for example in the area of the extinguishing agent supply connection 23a. A mass flow of the provided extinguishing agent can be adjusted by means of the valve element 24 in dependence on the detection of the heating state Z. In this case, for example, a control signal can be provided by the detection device 30 to an actuator of the valve element 24 when the heating state Z is detected. The valve element can be put into an open position by the control signal, so that the extinguishing agent reservoir 50 and the battery housing are fluidically connected to one another. The extinguishing agent can thus flow into the battery housing 13. Otherwise, the valve element 24 is in a closed position, in which a pressure of the extinguishing agent is applied to a valve body of the valve element 24, but the valve element blocks the mass flow.

[0054] The valve element 24 can additionally be secured or protected against vandalism or misuse from the outside. This means that the valve element only opens, for example, when the control signal from the detection device 30 confirms the presence of the heating state Z. Mechanical opening, on the other hand, is not possible. Alternatively, a mechanical opening or unlocking of the valve element can be possible, for example, using a predetermined unlocking unit. Thus, the fire department can use the extinguishing agent supply unit 23a, for example, to supply an extinguishing agent. For example, a predetermined key or a corresponding unlocking code, which is provided in the detection device 30, can be provided here as the unlocking unit.

[0055] To improve the extinguishing effect, the battery housing 13 has, as shown in FIG. 1, an extinguishing agent outlet element 14 for discharging the extinguishing agent introduced into the battery housing 13. The extinguishing agent outlet element 14 can be designed, for example, as a pressure compensation valve. This means that the extinguishing agent outlet element can be adjusted automatically between the open and the closed position in dependence on a pressure which acts on a valve body. A steady flow of extinguishing agent in the battery housing 13 can thus be ensured and improved cooling or firefighting can be implemented as a result.

[0056] Additionally or alternatively to the extinguishing agent outlet element 14, the charging device 20 can be supplemented by an extinguishing agent discharge unit (not shown in FIG. 1) in order to provide a steady extinguishing agent flow. This can be implemented analogously to the extinguishing agent supply unit 23, wherein the extinguishing agent discharge unit is designed to be coupled to a motor vehicle-external waste water reservoir. The supplied extinguishing agent can be discharged from the battery housing 13 to the waste water reservoir by means of the extinguishing agent discharge unit. Therefore, the contaminated extinguishing agent, i.e., the extinguishing agent that was exposed to electrochemistry of the battery cells 12, does not need to be released to the surroundings or to the environment. Instead, it can be temporarily stored in the waste water reservoir, such as a tank, until treatment or purification.

[0057] FIGS. 2 and 3 now show exemplary design options of how the charging device 20 can be implemented or embodied in the motor vehicle 1. This relates in particular to how the charging connection 22a and the extinguishing agent supply connection 23a can be designed. A common supply area 25 is provided in FIG. 2 and FIG. 3, from which the charging connection 22a and the extinguishing agent supply connection 23a are led out to an outer surface or surface of the motor vehicle 1. The supply area 25 of the charging device 20 can be provided with a locking mechanism, for example by means of a locking element, in order to permit or prevent access to the charging device. The closure element can be implemented, for example, by a charging connection flap of the motor vehicle 1 (not shown in FIGS. 2 and 3). The charging connection flap 22a and the extinguishing agent supply connection 23a can be covered from the outside by means of the charging connection flap.

[0058] According to FIGS. 2 and 3, the charging connection 22a is designed as a known electrical connection (high-voltage plug unit) for an electric or hybrid vehicle. The extinguishing agent supply connection 23a is designed accordingly as a standard water connection. To connect the motor vehicle-external energy supply system 40 or the extinguishing agent reservoir 50, a counterpart corresponding to the charging connection 22a and the extinguishing agent supply connection 23a can be provided as the respective connection element. For coupling, the respective mating connecting elements or connecting parts can be connected to one another in a known manner, for example in a plug connection or catch connection.

[0059] In FIG. 2, the extinguishing agent supply connection 23a and the charging connection 23a are designed as separate connection elements in the supply area 25. This means that two separate connecting or plugging processes are necessary in order to connect the motor vehicle-external energy supply system 40 and the motor vehicle-external extinguishing agent reservoir 50 to the battery arrangement 10.

[0060] In contrast to this, the charging connection 22a and the extinguishing agent supply connection 23a according to FIG. 3 form a common connection element. This means that the extinguishing agent supply connection 23a is combined with the connection element according to FIG. 1, which includes the charging connection 22a, in a common connection element 21. Thus, only one connecting or plugging process is necessary in order to be able to connect both the energy supply system 40 and the extinguishing agent reservoir 50 to the battery arrangement 10. As a result, the user only needs to apply one plug, as has been the case with battery-electric vehicles until now.

[0061] When the battery arrangement 10 described is used in a motor vehicle, the following procedure can be provided for fighting a battery fire. A customer can park his vehicle in a parking lot and connect the charging plug (energy supply system 40) and an external water line (extinguishing agent reservoir 50) to the charging device 20 of the battery arrangement 10. The water pressure of the water line, i.e., the extinguishing agent reservoir 50 external to the vehicle, is then applied to the electrically activatable valve element 24. If the vehicle now detects a critical temperature increase in the battery 11, the temperature information, i.e., the sensor data, can be processed in the central on-board computer. At the same time, an emergency call can be made and the fire department can, for example, view vehicle data via the Internet. For example, location information or access to a location system (GPS of the motor vehicle 1) can be transmitted or granted to the fire department. In addition, the central on-board computer, i.e., the control unit 31a, can initiate the flooding of the battery 11. This means that the inflow of the extinguishing agent into the battery housing 13 can be triggered by communication or by activation of the electrically activatable valve element 24. The valve element 24 opens and the extinguishing agent can penetrate into the battery housing 13. Motor vehicle (10) having a battery arrangement (11) according to any one of preceding claims 1 to 7.

[0062] Overall, the invention provides a combined charging plug having an integrated water connection. This results in the advantage that water pressure is applied to the water line for supply to the battery arrangement 10 at all times. This means that a battery fire can be extinguished immediately after thermal runaway has been detected. In the best case, extinguishing agents, such as water, can be introduced into the battery housing at an early stage so that a fire does not start in the first place. The time span until the arrival of the fire department can thus be bridged effectively. Overall, high property damage, for example to vehicles or buildings, can be effectively avoided. As a result, battery-electric vehicles can also in future be parked in areas that are difficult to access without fear of higher insurance ratings or such vehicles being banned.