Cooling device, motor vehicle battery and method for operating a cooling unit

Abstract

A cooling device (12) for cooling a battery (10) of a motor vehicle having a plurality of individual cells (14, 14a, 14b), wherein the cooling device (12) has a plurality of cooling units (22, 22a, 22b), each of the cooling units (22, 22a, 22b) being assigned to one of the individual cells (14, 14a, 14b), the cooling device (12) having a control device (24) designed to control the cooling power of each of the cooling units (22, 22a, 22b) individually. The control device (24) is designed to control the cooling units (22, 22a, 22b) in a defined first cooling mode (M1) in a different manner than in a defined second cooling mode (M2) different from the first cooling mode. The cooling device (12) is set up to switch from the first cooling mode (M1) to the second cooling mode (M2) in the event of a fault condition (F) involving a first individual cell (14, 14a) of the plurality of individual cells (14, 14a, 14b).

Description

Technical Field

[0001] This invention relates to a cooling device for cooling a single-cell assembly having multiple individual cells in a motor vehicle battery. The cooling device has multiple cooling units, each of which is assigned to one of the individual cells. Each cooling unit has a control device designed to individually control the cooling power of each cooling unit. Furthermore, this invention also relates to a motor vehicle battery having such a cooling device and a method for operating the cooling units. Background Technology

[0002] Batteries for motor vehicles, particularly electric or hybrid vehicles, are known in the prior art. These batteries are typically constructed as high-voltage batteries and comprise multiple individual cells, which may also form battery modules. The cells must be cooled during charging and during vehicle operation. For this purpose, current high-voltage batteries are equipped with large cooling plates according to existing technology. Here, all or at least multiple individual modules are positioned on a single cooling plate. Thus, multiple individual modules always share a single cooling plate. Cooling water is always simultaneously distributed across all modules positioned on this common cooling plate. Since the modules are distributed on a common cooling plate, a disadvantage is that these modules can only be cooled or heated collectively. Therefore, individual modules cannot be cooled specifically. Consequently, the cooling power is always controlled according to the cooling requirements of the hottest module. To avoid this disadvantage, cooling systems that achieve individual cooling of individual cells or battery modules are also known in the prior art.

[0003] For example, WO 2013 / 178577 A1 describes a coolant distribution system capable of cooling individual cells separately. Furthermore, DE 10 2010 025 525 A1 describes a method for cooling a battery pack, wherein at least one battery pack is divided into multiple modules, each module being cooled individually. Here, the cooling of one module can be performed independently of the cooling temperatures of other modules. However, the cooling of one module can also be performed based on the temperature of another module with the highest temperature value. Simplification is achieved here by adjusting only based on the temperature of the hottest module. However, this compromises the advantages of the individually cooled approach.

[0004] In addition, DE 10 2016 215 851 A1 also describes a cooling device for battery components. Here, the cooling device has at least two individually designed individual cooling elements opposite to the battery, each of which is supplied with coolant through its own valve associated with the respective individual cooling element.

[0005] In addition, DE 10 2019 213 757 B3 describes a cooling circuit device for a battery device having multiple battery modules, wherein a coolant valve associated with the corresponding battery module is opened, particularly for the purpose of cooling the relevant battery module, when the operating temperature of the corresponding battery module exceeds a predetermined threshold, or particularly for the purpose of heating the battery module, when the operating temperature is below a predetermined threshold.

[0006] In the system described above, the premise is always to cool all the battery cells as uniformly as possible to achieve the most uniform aging of all the battery cells, thereby maximizing the overall battery life. However, other aspects, especially safety, are neglected. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide a cooling device, a motor vehicle battery, and a method that improves safety related to motor vehicle batteries.

[0008] This objective is achieved by a cooling device, a motor vehicle battery, and a method having the features according to the respective independent claims. The subject matter of the dependent claims, the specification, and the drawings represents advantageous embodiments of the invention.

[0009] The cooling device for cooling a vehicle battery cell assembly having multiple individual cells according to the present invention has multiple cooling units, wherein each cooling unit is assigned to one of the individual cells, and the cooling device has a control device designed to control the cooling power of each cooling unit in the cooling unit separately. Here, the control device is designed to control the cooling units in a different manner in a defined first cooling mode than in a defined second cooling mode different from the first cooling mode, wherein the cooling device is configured to switch from the first cooling mode to the second cooling mode in the event of a failure involving a first individual cell among the multiple individual cells.

[0010] Here, the present invention is based on several understandings: in many cases, such as under external force or short circuit, a single battery cell may experience thermal penetration. This causes intense heat release in the cell in question, which is also transferred to adjacent cells in the module. These adjacent cells may also experience thermal penetration, leading to heat propagation. If the cell or module is intensely cooled, this heat propagation can be prevented or at least delayed in time. However, very high cooling power is required to delay or even prevent this heat propagation as effectively as possible, which is typically not provided by conventional cooling equipment or strategies. This is particularly impossible when cooling all cells or modules together via a common cooling plate, as the required cooling power at the module is reduced due to cooling all modules. Even in cooling systems that allow individual cooling of modules, the maximum cooling power achievable for a particular module under conventional cooling strategies is significantly limited when simultaneously cooling other modules. This is advantageously overcome here by providing at least two different cooling modes. Here, the first cooling mode corresponds to the conventional cooling mode, according to which the control device controls the cooling unit when no fault is detected. Such control can be performed, for example, as described in the prior art. In this first cooling mode, each individual cooling unit can be controlled independently, for example, according to the corresponding temperature of its associated unit. For example, a unit that is hotter than other units can be cooled more strongly than other units. It is also conceivable to cool all units in association in the first cooling mode. That is, in the first cooling mode, it is not necessary to cool all units individually. For example, in the first cooling mode, the cooling power of all cooling units can be set the same, for example, according to the temperature of the hottest unit. Conversely, the second cooling mode advantageously allows for, for example, another control strategy, according to which the cooling of the faulty first unit is prioritized. This means that achieving the adjustment objectives related to the cooling of the remaining units can be correspondingly secondary. This, in turn, advantageously enables targeted and prioritized cooling of the faulty unit in the event of a fault, especially in the event of thermal runaway, and, for example, concentrates the maximum cooling power available from the cooling equipment on the relevant unit. This may also include, for example, the remaining units being completely de-cooled in order to maximize the cooling power used on the relevant first unit. Therefore, in the second cooling mode, achieving the most uniform cooling possible for all cells or cell modules is secondary or completely unimportant. In this second cooling mode, every effort is made to prevent heat propagation or at least delay it for as long as possible. Through this control strategy, or a possible switching of this control strategy, or in general, a switching of cooling modes, the safety associated with automotive batteries can be significantly improved.

[0011] Here, the transition from the first cooling mode to the second cooling mode can also be controlled by a control device. In particular, the control device can also be designed to switch from the first cooling mode to the second cooling mode upon detection of a fault related to the first unit among multiple individual units. However, this transition can also be passively controlled, for example, by a passively controllable valve in the relevant cooling circuit. For example, it is feasible to use the heat generated in the module or individual unit to passively control a valve in the cooling circuit based on temperature, for example, by a bimetallic strip. Thus, the valve can be automatically moved to a predetermined valve position when the temperature is sufficiently high without the need for control device intervention, depending on which valve position, for example, an additional cooling circuit of the relevant cooling unit that is not used in the first operating mode is released to allow coolant flow. Such a valve can also passively move to a maximum open position that would never be occupied in the first cooling mode when the temperature is sufficiently high. In this passive control or this passive cooling mode transition, no additional sensing device is required to detect thermal runaway.

[0012] Here, a single cell can be understood not only as a single battery cell, but also as a group of cells or multiple cells within such a group. Preferably, a single cell comprises multiple battery cells. For example, a single cell can also be a battery module comprising multiple battery cells. Here, the single cell forming the cell assembly is part of a motor vehicle battery. The motor vehicle battery is preferably configured as a high-voltage battery. Furthermore, the motor vehicle battery serves as a power battery for a motor vehicle. The battery cell can be, for example, a lithium-ion cell. Each cooling unit can be configured, for example, as a cooling plate or cooling base plate, and in particular, each cooling unit is preferably through which a coolant, such as a water-glycol mixture, flows. In principle, the cooling device can be used not only to cool the individual single cells, but also, for example, to heat the single cells.

[0013] Furthermore, the control device can be designed to receive a detection signal from a detection device used to detect fault conditions. This detection signal notifies the control device that a fault condition has been detected or exists. Accordingly, upon receiving this definitive detection signal indicating the existence of a definitive fault condition, the control device can trigger or activate a switch from a first cooling mode to a second cooling mode and accordingly change its control strategy for manipulating the cooling unit. Here, the control device can also be designed to determine which of a plurality of individual units has detected a relevant fault condition. In particular, this can also be communicated to the control device via the detection signal. For example, each individual unit, such as a single module, can be equipped with its own module control unit. If the relevant module control unit detects a relevant fault condition, such as when the module temperature exceeds a predetermined limit, the relevant module control unit can inform the control device, which could be, for example, a higher-level controller, such as a battery management controller. Based on which module control unit the control device received the detection signal from, it is also correspondingly determined which individual unit in the unit has been damaged or faulty. Therefore, another highly advantageous design of the invention is that the cooling device has a detection device designed to detect fault conditions. Here, for example, such a detection device can also be provided for each individual unit, such as a battery module. This detection device may include one or more sensors for detecting fault conditions. If a fault condition is detected in a single unit, the detection device can transmit the corresponding information to the control device.

[0014] Furthermore, it is highly advantageous that the detection device is designed to detect the temperature of the first unit cell in order to detect a fault condition, and to detect a fault condition when said temperature exceeds a predetermined first limit. In particular, thermal penetration of a single unit cell can be detected with particular reliability based on the temperature of that single unit cell or only one unit cell within that unit cell. Thus, if the predetermined limit is exceeded, this indicates the onset of such thermal penetration, and advantageously, countermeasures can be taken immediately by purposefully and particularly preferentially cooling the first unit cell. For example, the predetermined limit may be in the temperature range between 50°C and 70°C, such as 60°C. However, a larger predetermined limit may also be selected, for example, in the range between 90°C and 130°C, particularly in the range between 100°C and 120°C. However, multiple limits may also be set to implement a suitable cooling strategy in the second cooling mode, as explained in detail later. This achieves a stepwise adjustment of the cooling strategy to prevent heat propagation as effectively as possible.

[0015] However, it is not necessary or permissible to detect a determined fault condition solely based on the obtained temperature of the relevant individual cell; alternatively, it can be detected in other ways. For example, other methods include detecting the cell voltage, especially voltage interruption, and / or detecting overvoltage within the cell housing and / or module housing, detecting gases escaping from the battery cell, etc. Accordingly, the detection device may include not only one or more temperature sensors, but also other sensors such as gas sensors, pressure sensors, voltage sensors, and / or current sensors. This enables reliable detection of the presence of fault conditions, particularly those representing thermal penetration of the cell or at least the onset of such thermal penetration.

[0016] According to another advantageous design of the invention, the cooling device has a cooling circuit through which coolant can flow, wherein the cooling unit is configured to be through which coolant can flow and is part of the cooling circuit, wherein each cooling unit is provided with at least one valve device of the cooling device, which is particularly controllable by a control device, by means of which the flow rate of coolant through the corresponding cooling unit can be adjusted, particularly the flow rate, and wherein coolant can be supplied to the cooling unit through a common supply line of the cooling device and / or a common coolant reservoir of the cooling device.

[0017] This structure enables particularly simple and individual control of individual cooling units. Here, the valve device can be configured as a valve, particularly an electrically or electromagnetically controllable valve. However, it is also feasible to use the heat generated in the module with the penetrated unit to passively control the valve, for example, via a bimetallic strip based on temperature. Thus, no additional sensing device is needed to detect thermal runaway. Therefore, the transition from a first cooling mode to a second cooling mode is passively achieved by changing the valve position of the valve associated with the cooling unit and the penetrated unit or unit in relation to temperature. This passive valve opening, for example, can release additional cooling circuits or additional cooling channel circuits that additionally cool the corresponding cooling unit but are not used in the first cooling mode. This increases the flow rate through the relevant cooling unit, thereby automatically reducing the flow rate of other cooling units when they are connected to the same cooling circuit. For example, a valve in the form of a throttle valve can be provided. It is also conceivable to control the valve device via a control device. This allows for particularly simple adjustment of the flow rate. Therefore, if the valve device for a particular cooling unit in the cooling system is closed, coolant does not flow through that cooling unit or at least not through the additional cooling circuit, and the flow rate is zero. If the valve device is open, coolant flows through the associated cooling unit or the additional cooling circuit, and the flow rate is not zero. The flow rate can then be appropriately adjusted according to the valve position. A common supply line can be used to supply coolant to individual cooling units. This common supply line can, for example, branch into individual supply paths for each cooling unit. In other words, each corresponding supply path can be arranged with its own cooling unit and its associated valve or valve device. Here, the associated valve device can be connected before or after the corresponding cooling unit in the flow direction. Furthermore, the individual supply paths can converge again downstream into a common discharge line. The common supply line and common discharge line simplify the structure of the cooling circuit because common circuit components can be used, such as a common pump, for example a water pump, or a common coolant reservoir, for example a water tank. In a specific example (in which each individual unit is a single module and the cooling unit is provided as a cooling plate), each cooling plate has its own valve, allowing stepless adjustment of the cooling power for each module. In cases of thermal runaway with severe heat generation and the resulting heat propagation, cooling power can be selectively delivered to the failed module via individual cooling plates and associated valves, thereby cooling and dissipating heat more effectively. This slows heat propagation and thus improves system safety. That is, the focus here is not on the actual condition of the cooling plate for each individual module, but on targeted operating strategies that can cool individual modules to delay or even prevent heat propagation. The highly advantageous cooling strategies will now be explained in detail.

[0018] In another advantageous embodiment of the invention, a first unit is assigned to a first cooling unit among a plurality of cooling units, and a second unit, different from the first unit, is assigned to a second cooling unit among a plurality of cooling units. In other words, exemplarily, a unit with damage or a known fault condition is referred to as the first unit, and all the remaining units are referred to as the second unit. Correspondingly, the cooling unit assigned to the first unit is referred to as the first cooling unit, and all the remaining cooling units are referred to as the second cooling units. According to a highly advantageous embodiment of the invention, the control device is now configured to deactivate at least one of the second cooling units in the second cooling mode. In other words, the control device manipulates the second cooling unit, particularly the valves associated with the second cooling unit, so that the deactivated second cooling unit is no longer circulated by coolant. For example, the valve device assigned to the second cooling unit is closed by the control device. This deactivation of the second cooling unit is independent of whether the second unit to which the deactivated second cooling unit is assigned currently has a cooling requirement. This is based on the understanding that by intentionally deactivating the cooling unit, the maximum cooling power available from the first cooling unit can be increased. This is achieved, in particular, by having each individual cooling unit share a common cooling circuit assembly, such as the aforementioned pump or coolant reservoir, and be supplied through this common supply line. This cannot be achieved if each individual cooling unit is arranged in a separate cooling circuit with its own cooling circuit assembly. In this way, the maximum available cooling power can be concentrated on the faulty cell, the faulty cell module, or the group of cells with the faulty battery module. This significantly increases the possibility of preventing or stopping heat transfer.

[0019] According to another advantageous embodiment of the invention, the control device is configured to, in the second cooling mode, increase the cooling power allocated to the first cooling unit and / or maximize the cooling power allocated to the first cooling unit under at least one predetermined boundary condition. In principle, there are several feasible schemes for implementing controllable and cooling strategies in the second cooling mode. Here, it is highly advantageous, for example, to deactivate at least one of the second cooling units to increase the cooling power for the first cooling unit, as described above. However, it is not necessary to immediately switch to such deactivation in the second cooling mode upon detecting such damage or failure of the first unit. It is also conceivable, for example, to implement the cooling strategy in multiple stages. For example, the cooling power for all the remaining second cooling units may be slightly reduced before switching to deactivation. But in all these cases, it is highly advantageous to increase the cooling power of the first cooling unit and / or maximize the cooling power of the first cooling unit under defined boundary conditions. For example, the boundary conditions define the stages for each individual unit. The increase in cooling power here is particularly referenced to a comparison with the cooling power in the first cooling mode and / or a comparison with the cooling power of other second cooling units.

[0020] In another highly advantageous embodiment of the invention, the predetermined boundary conditions include controlling the second cooling unit in the same manner as in the first cooling mode, and / or operating at least one, and especially all, of the second cooling units at a lower cooling power compared to the first cooling mode, and / or deactivating at least one of the second cooling units. In particular, it is also possible to deactivate all cooling units in the second cooling unit. For example, it can be specified that when, for example, a fault condition is detected and the temperature associated with the first unit module is greater than a first predetermined limit, such as 60 degrees Celsius, the control device controls the cooling units such that the cooling power used first for the first cooling unit is maximized, while the second cooling units are still controlled in the same manner as in the first cooling mode. In other words, the second cooling units can be regulated according to temperature, for example, as is currently done, so that the temperature of the second cooling units is within a predetermined rated range, for example, between -30°C and +60°C. Meanwhile, the cooling power used for the first cooling unit is maximized, at least within the remaining cooling power framework. For example, the valve allocated to the first cooling unit can be fully opened. However, if the temperature of the first unit module continues to rise, the control device may switch to reducing the cooling power used for the remaining second cooling units. Cooling of the second cooling units can also be achieved in this case. Alternatively, the control device may immediately switch to this cooling strategy of reducing the cooling power used for the second cooling units when the first limit is exceeded. Subsequently, if the temperature of the first unit module continues to rise and, for example, exceeds a second limit, such as 100°C or 120°C, the control device may switch to deactivating at least one of the second cooling units or deactivating all of the second cooling units. Here, the deactivation of the second cooling units can also be performed gradually, as will be explained in detail below. Subsequently, increasingly higher cooling power can be gradually provided to cool the first unit module. Alternatively, the control device may immediately switch to deactivating at least one of the second cooling units when a fault condition is detected and the temperature exceeds a predetermined temperature limit of the first unit module. This maximizes safety because it prevents heat transfer as much as possible.

[0021] In another advantageous embodiment of the invention, the control device is configured to deactivate at least one second cooling unit and / or all second cooling units in the second cooling unit according to the position of the second cooling unit relative to the first cooling unit in the second cooling mode. For example, it may be specified that the cooling unit spatially furthest from the first cooling unit assigned to the damaged unit module is deactivated first. This is based on the understanding that heat propagation typically spreads rapidly to adjacent modules. To prevent or delay this propagation, i.e., to other second unit modules arranged adjacent to the first unit module, such as the first unit module, the adjacent unit module may also be cooled. However, the cooling power for the first unit module and, in particular, the adjacent unit modules also used by the first unit module can be increased by deactivating the more distant second cooling units. It is also conceivable that all second cooling units assigned to unit modules not affected by the fault condition are immediately deactivated once the fault condition is detected.

[0022] This provides several advantageous and feasible solutions for stopping or at least delaying heat propagation in a suitable manner.

[0023] Furthermore, the present invention also relates to a motor vehicle battery having a cooling device or design thereof according to the invention. Thus, the advantages described for the cooling device and design thereof according to the invention are applied in the same manner to the motor vehicle battery according to the invention. Here, the motor vehicle battery may comprise a cell assembly having multiple individual cells. These individual cells may be constructed as described above. Each cooling unit is assigned to its respective individual cell. The motor vehicle battery is preferably constructed as a high-voltage battery.

[0024] Furthermore, the present invention also includes motor vehicles having a cooling device according to the present invention or one of the designs thereof, or having a motor vehicle battery according to the present invention or one of the designs thereof.

[0025] The motor vehicle according to the invention is preferably designed as an automobile, especially a passenger car or a truck, or a bus or motorcycle.

[0026] Furthermore, the present invention also relates to a method of operating multiple cooling units for cooling a single-unit assembly having multiple individual units, wherein each cooling unit in the cooling unit is assigned to one of the individual units, particularly exactly one individual unit. Furthermore, a control device controls the cooling power of each cooling unit in the cooling unit separately. Moreover, in a defined first cooling mode, the control device controls the cooling units in a different manner than in a defined second cooling mode different from the first cooling mode, wherein the switching from the first cooling mode to the second cooling mode is based on a fault condition involving the first individual unit among the multiple individual units.

[0027] The advantages described herein, in conjunction with the cooling device and its design according to the invention, are equally applicable to the method according to the invention.

[0028] Here, the control device can specify how to control the cooling unit in a given cooling mode by storing corresponding control strategies in its memory. The control device controlling the cooling unit in a different manner in the first cooling mode than in the second cooling mode means that a different control strategy is specified for the first cooling mode than for the second cooling mode. In other words, for example, one control strategy can be assigned to the first cooling mode, and a different control strategy can be assigned to the second cooling mode. The control strategies can be stored in the control device and used depending on whether a fault condition is detected. Therefore, correspondingly, once a fault condition of the first unit is detected, the control device can switch from the first cooling mode to the second cooling mode and correspondingly switch from the first control strategy to the second control strategy.

[0029] The present invention also includes a control device for a motor vehicle. The control device may have a data processing device or a processor device configured to execute embodiments of the method according to the invention. For this purpose, the processor device may have at least one microprocessor and / or at least one microcontroller and / or at least one FPGA (Field Programmable Gate Array) and / or at least one DSP (Digital Signal Processor). Furthermore, the processor device may have program code configured to execute embodiments of the method according to the invention when run by the processor device. The program code may be stored in the data memory of the processor device.

[0030] This invention also includes improvements to the method according to the invention, which have the features already described in conjunction with improvements to the cooling device according to the invention. For this reason, corresponding improvements to the method according to the invention will not be described again here.

[0031] The present invention also includes combinations of features from the described embodiments. Therefore, the present invention also includes implementations having combinations of features from multiple embodiments described, provided that these embodiments are not described in a mutually exclusive manner. Attached Figure Description

[0032] The embodiments of the present invention will be described below. Wherein:

[0033] Figure 1 A schematic diagram of a motor vehicle battery with a cooling device according to an embodiment of the present invention is shown;

[0034] Figure 2 A schematic diagram of a motor vehicle battery with a cooling device in a first cooling mode according to an embodiment of the present invention is shown; and

[0035] Figure 3 The second cooling mode of the cooling device according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of a motor vehicle battery. Detailed Implementation

[0036] The embodiments explained below are preferred embodiments of the present invention. The components of the embodiments described in the embodiments represent individual features of the invention that are considered independent of each other, and these features also individually improve the invention. Therefore, the disclosure should also include combinations of features different from those of the illustrated embodiments. Furthermore, the described embodiments may also be supplemented by other features of the invention already described.

[0037] In the figure, the same reference numerals represent elements with the same function.

[0038] Figure 1 A schematic diagram of a motor vehicle battery 10 with a cooling device 12 according to an embodiment of the present invention is shown. The motor vehicle battery 10 may be configured as a high-voltage battery, for example. Furthermore, the motor vehicle battery 10 includes a plurality of individual cells 14 arranged in a single cell assembly 16. In this example, the respective individual cells 14 are configured as battery modules 14. Each battery module 14 further includes a plurality of battery cells 18. For visibility reasons, only one battery cell 18 for each module 14 is referred to herein. Figure 1 A top view of the battery 10 is shown, particularly regarding its conventional installation location in a motor vehicle. However, other installation locations are also conceivable. Each battery cell 18 has two individual electrodes 20. In this example, the individual electrodes are arranged on the upper side of each individual cell 18; however, in principle, they could also be arranged on other sides of each individual cell 18. Furthermore, the cooling device 12 includes a plurality of cooling units 22. Here, each cooling unit 22 is assigned to a battery module 14, specifically exactly one battery module 14. In this example, each cooling unit 22 is configured as a cooling plate 22. For example, each cooling unit 22 can also be provided or formed by a common, identical cooling plate, whereby, for example, each plate portion 22 can have, for example, its own cooling channel system. Thus, in principle, each individual cooling unit 22 can be configured as a cooling plate 22 through which coolant can flow. Furthermore, the cooling device 12 includes a control device 24 for operating each respective cooling unit 22. Here, the control device 24 is designed to operate each individual cooling unit 22 individually. In other words, the control device 24 can also set different cooling powers for each cooling unit 22 as needed. This allows the battery modules to be cooled according to their individual cooling needs. Additionally, this also significantly improves the safety of the battery 10, as explained in detail later.

[0039] also, Figure 2 and Figure 3 Schematic diagrams of a battery 10 according to another embodiment of the present invention are shown. In principle, the battery 10 can be configured as described above... Figure 1 The structure described above is illustrated here, but for better explanation, only the two battery modules 14 of battery 10 and the cooling units 22 allocated to them are shown. Here, the first battery module 14 is designated 14a, and the second battery module 14 is correspondingly designated 14b. The cooling unit 22 allocated to the first battery module 14a is also designated 22a, and additionally, the cooling unit 22 allocated to the second battery module 14b is also designated 22b. Here, the cooling unit 22 is part of a cooling circuit 26. The cooling circuit 26 is further included in the cooling device 12. Here, the cooling circuit 26 has a coolant reservoir, such as a water tank 28, and a coolant pump 30, such as a water pump. Furthermore, as part of the coolant circuit 26, a common supply line 32 is provided for supplying the individual cooling units 22. This common supply line branches into individual supply paths 34a, 34b, each arranged with its respective cooling unit 22a, 22b. In the flow direction, particularly indicated by arrow 36, the individual supply paths 34a and 34b can converge again into a common discharge pipe 38. Therefore, the discharge pipe 38 serves as a return section, and the delivery or supply pipe 32 serves as an inflow section. Consequently, a corresponding cooling unit 22 is arranged in each individual supply path 34a and 34b. Additionally, a valve device associated with each cooling unit 22a and 22b is arranged in each of the respective supply paths 34a and 34b. For simplicity, the valve device is hereinafter referred to as valve 40a and 40b.

[0040] Therefore, in this example, each individual module 14 of the battery 10 has a respective cooling plate in the form of a cooling unit 22. The cooling plate 22 has a water inlet or outlet, i.e., a corresponding valve 40a, 40b, which may be electronically controlled, for example. In this example, the valve position can be changed by a motor 42. This control is performed by a control device 24. Valves 40a and 40b may be valves with electromagnetic actuators or valves with linear actuators, respectively.

[0041] In addition, each battery module 14 has a temperature monitoring element. For this purpose, one or more temperature sensors can be provided for each module 14. Figure 2 and Figure 3 In this paper, only one of these temperature sensors 44a and 44b is shown. However, it is also possible to provide only one of these temperature sensors 44a and 44b for each battery module 14. The control device 24 may also have a detection module 46, which is designed to detect a temperature detection fault F obtained by means of the temperature sensors 44a and 44b (see Figure 3For example, when the detected temperature of the relevant module 14 exceeds a predetermined limit, a fault condition F is considered to have been detected. Figure 3 In the example shown, the first module 14a has this fault F. Conversely, Figure 2 The case where this fault F does not exist is shown. Accordingly, Figure 2 The diagram corresponds to normal operation. Accordingly, control device 24 controls valves 40a and 40b according to the first cooling mode M1. In this case, both valves 40a and 40b are at least partially open. Accordingly, cooling power is provided to both battery modules 14a and 14b through cooling units 22a and 22b, which are circulated by coolant according to the valve positions. In the first cooling mode M1, for example, it may be specified that both cooling units 22a and 22b are controlled simultaneously, or each cooling unit 22a and 22b may be controlled according to the temperature of the respective assigned individual modules 14a and 14b, which is obtained by means of the assigned temperature sensors 44a and 44b.

[0042] Now, if the detection module 46 detects a fault condition F, the control device 24 can advantageously switch from the first cooling mode M1 to the second cooling mode M2. The difference between the second cooling mode and the first cooling mode M1 lies in the different operation of the cooling unit 22. According to this changed operation, the faulty module 14a is cooled preferentially. This preference can take several forms. For example, the first cooling unit 22a can be operated at the maximum available cooling power, but the second cooling unit 22b continues to cool the second module 14b. It is also conceivable to reduce the cooling power provided by the second cooling unit 22b. However, the second cooling unit 22b can also be completely deactivated, for example, in Figure 3 As exemplarily illustrated, the control device 24 manipulates the second valve 40b such that it is now in the closed position G. Consequently, the flow rate in the second path 34b is zero. Thus, all the cooling power available from the cooling system can be concentrated on cooling the first module 14a.

[0043] Therefore, by monitoring the temperature in the individual module 14a, a signal is sent to the controller or battery management system, represented here by the control device 24, when the rated value is exceeded. Here, the controller 24 locates the position of the dangerous module 14a and blocks all the cooling plates 22 of the unaffected module 14a by manipulating the circuit. The faulty individual module 14a also has an open cooling plate 22a and can thus be cooled in a targeted manner. By blocking the remaining cooling plates 22b of the unaffected individual modules 14a, the volumetric flow of cooling water in the first cooling plate 22a of the faulty individual module 14a is also increased. As a result, the cooling power in the faulty individual module 14a is significantly increased. This advantageously achieves the ability to significantly delay and even potentially prevent thermal runaway and related heat propagation, even using conventional cooling methods.

[0044] Alternatively, it may be conceivable to also cool the adjacent battery modules 14a that are also malfunctioning, while only activating the battery modules 14 located further away and their assigned cooling units 22. Thus, by cooling the adjacent modules 14, the spread of heat propagation can also be prevented.

[0045] In general, the examples demonstrate how the present invention can provide switchable cooling in high-voltage batteries to prevent heat propagation.

Claims

1. A cooling device (12) for cooling a single-cell assembly (16) having multiple single-cell units (14, 14a, 14b) for a motor vehicle battery (10). - in, The cooling device (12) has multiple cooling units (22, 22a, 22b); - Each cooling unit in the cooling units (22, 22a, 22b) is assigned to one of the individual units (14, 14a, 14b); - The cooling device (12) has a control device (24) designed to control the cooling power of each cooling unit in the cooling units (22, 22a, 22b) respectively. Its features are, The control device (24) is designed to control the cooling units (22, 22a, 22b) in a different manner in a determined first cooling mode (M1) than in a determined second cooling mode (M2) which is different from the first cooling mode. The cooling device (12) is configured to switch from the first cooling mode (M1) to the second cooling mode (M2) in the event of a failure (F) of the first individual unit (14, 14a) among the multiple individual units (14, 14a, 14b). The control device (24) is configured to switch from a first cooling mode (M1) to a second cooling mode (M2) when a fault condition (F) involving the first of a plurality of individual units (14, 14a, 14b) is detected, wherein the cooling device (12) has a detection device (46) designed to detect the fault condition (F). A first unit (14, 14a) is assigned to a first cooling unit (22, 22a) among a plurality of cooling units (22, 22a, 22b). Second units (14, 14b) that are different from the first unit (14, 14a) among the plurality of unit units (14), are respectively assigned to second cooling units (22, 22b) that are different from the first cooling unit (22, 22a) among the plurality of cooling units (22, 22b). The control device (24) is configured to deactivate at least one cooling unit among the second cooling units (22, 22b) in a second cooling mode (M2). First, activate the cooling unit that is spatially furthest from the first cooling unit assigned to the damaged individual module. At least one of the second cooling units is deactivated to increase the cooling power used for the first cooling unit.

2. The cooling device (12) according to claim 1, characterized in that, The detection device (46) is designed to detect the temperature of the first unit (14, 14a) in order to detect fault condition (F), and to detect fault condition (F) when the temperature exceeds a predetermined first limit.

3. The cooling device (12) according to claim 1, characterized in that, The cooling device (12) has a cooling circuit (26) through which coolant can flow, wherein cooling units (22, 22a, 22b) are configured to be through which coolant can flow and are part of the cooling circuit (26), wherein each cooling unit in the cooling units (22, 22a, 22b) is provided with at least one valve device (40a, 40b) of the cooling device (12) that can be controlled by a control device (24), wherein the flow rate of coolant through the corresponding cooling unit (22, 22a, 22b) can be adjusted by means of the valve device, wherein coolant can be supplied to the cooling units (22, 22a, 22b) through a common supply line (32) of the cooling device (12) and / or through a common coolant reservoir (28) of the cooling device (12).

4. The cooling device (12) according to claim 1, characterized in that, A first unit (14, 14a) is assigned to a first cooling unit (22, 22a) among a plurality of cooling units (22, 22a, 22b), and a second unit (14, 14b) among the plurality of unit units (14, 14a, 14b) that is different from the first unit (14, 14a) is assigned to a second cooling unit (22, 22b) among the plurality of cooling units (22, 22a, 22b) that is different from the first cooling unit (22, 22a), wherein the control device (24) is configured to, in a second cooling mode (M2), increase the cooling power assigned to the first cooling unit (22, 22a) and / or maximize the cooling power assigned to the first cooling unit (22, 22a) under at least one predetermined boundary condition.

5. The cooling device (12) according to claim 4, characterized in that, The predetermined boundary conditions include: - Control the second cooling unit (22, 22b) in the same manner as in the first cooling mode (M1); and / or - At least one of the second cooling units (22, 22b) operates at a lower cooling power compared to the first cooling mode (M1); and / or - Deactivate at least one of the second cooling units (22, 22b).

6. The cooling device (12) according to claim 4 or 5, characterized in that, The control device (24) is configured to, in the second cooling mode (M2), deactivate at least one of the second cooling units (22, 22a, 22b) and / or deactivate all of the second cooling units (22, 22b) according to the position of the second cooling units (22, 22a) relative to the first cooling unit (22, 22a) in the second cooling mode (M2).

7. A motor vehicle battery (10) having a cooling device (12) according to any one of claims 1-6.

8. A method of operating multiple cooling units (22, 22a, 22b) for cooling a single-unit assembly (16) having multiple individual units (14, 14a, 14b), wherein, Each cooling unit in the cooling units (22, 22a, 22b) is assigned to one of the individual units (14, 14a, 14b), and wherein the control device (24) controls the cooling power of each cooling unit in the cooling units (22, 22a, 22b) respectively; Its features are, In the determined first cooling mode (M1), the control device (24) controls the cooling units (22, 22a, 22b) in a different manner than in the determined second cooling mode (M2) which is different from the first cooling mode, wherein the switch from the first cooling mode (M1) to the second cooling mode (M2) is based on the failure condition (F) of the first unit (14, 14a) among the multiple unit units (14, 14a, 14b). The control device (24) is configured to switch from a first cooling mode (M1) to a second cooling mode (M2) when a fault condition (F) involving the first of a plurality of individual units (14, 14a, 14b) is detected, wherein the cooling device (12) has a detection device (46) designed to detect the fault condition (F). A first unit (14, 14a) is assigned to a first cooling unit (22, 22a) among a plurality of cooling units (22, 22a, 22b). Second units (14, 14b) that are different from the first unit (14, 14a) among the plurality of unit units (14), are respectively assigned to second cooling units (22, 22b) that are different from the first cooling unit (22, 22a) among the plurality of cooling units (22, 22b). The control device (24) is configured to deactivate at least one cooling unit among the second cooling units (22, 22b) in a second cooling mode (M2). First, activate the cooling unit that is spatially furthest from the first cooling unit assigned to the damaged individual module. At least one of the second cooling units is deactivated to increase the cooling power used for the first cooling unit.

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