DE102021101215A1 - Method for operating a cooling device, cooling device and battery for a motor vehicle - Google Patents

Abstract

The invention relates to a method for operating a cooling device (12) for cooling at least one battery cell (14) of a battery (10) for a motor vehicle, the cooling device (12) having at least one cooling channel (18) through which a coolant (16) can flow, has one of the at least one battery cell (14) facing cooling side (26), which is at least partially flexible, wherein the cooling device (12) is controlled such that the at least one cooling channel (18) in a specific operating mode (B) of a coolant (16) with a definable operating pressure (p1) flows through it. The cooling device (12) is controlled in a time-limited calibration mode (K) that differs from the specific operating mode (B) in such a way that the coolant (16) flows through the at least one cooling channel (18) at a definable calibration pressure (p2), which is greater than the operating pressure (p1).

Description

The invention relates to a method for operating a cooling device for cooling at least one device, in particular a battery cell of a battery, for a motor vehicle, wherein the cooling device has at least one cooling channel through which a coolant can flow, which has a cooling side facing the at least one device, which has at least Part is flexible. The cooling device is controlled in such a way that, in a specific operating mode, a coolant with a definable operating pressure flows through the cooling channel. The invention also includes a cooling device for cooling at least one battery cell and a battery with such a cooling device.

Batteries, in particular high-voltage batteries, for electric or hybrid vehicles are usually cooled. Cooling plates are often used, on which the battery cells or battery modules are arranged. In order to optimize the heat transfer from the battery cells to the cooling plate, there should be as little air as possible between the battery cells and the cooling plate and the cooling should ideally be applied directly to the battery cells. However, due to tolerances in the component position and/or the components themselves, this is often not possible. The resulting gaps between the cooling plate and the battery cells are therefore often filled with a heat-conducting compound, also known as a gap filler, in order to improve heat transfer. Although such a gap filler has a higher thermal conductivity than air, its thermal conductivity is nevertheless significantly lower than, for example, that of typical metals. Accordingly, there is an effort to keep the gaps between a cooling plate and battery cells to be filled with such a gap filler as small as possible. This also resulted in additional cost and weight savings.

In order to be able to better bring a cooling plate into contact with a component to be cooled, cooling devices are also known from the prior art that can provide flexible cooling sides that can be inflated or inflated by a corresponding coolant pressure. For example, describes the DE 10 2018 216 713 A1 a cooling plate for controlling the temperature of a battery cell for a traction battery with a flow space for a coolant to flow through, and a flexible cover which at least partially delimits the flow space in a fluid-tight manner and is provided for thermal contacting of the battery cell. Furthermore describes the U.S. 2013/0250512 A1 a cooling device with an at least partially flexible cover that closes a fluid-carrying chamber. Furthermore describes the US 4,938,279A a heat sink with a flexible membrane that can be placed between two electronic units. By pumping a coolant into a sealed interior, this flexible membrane can be brought into contact with the electronic units. When the pressure is reduced, the flexible membrane returns to its non-deformed state. One electronic unit can then be exchanged for another without having to disassemble the heat sink.

Nevertheless, there is still a desire to further increase the cooling efficiency of a cooling device for a motor vehicle battery.

It is therefore an object of the present invention to provide a method, a cooling device and a battery that allow at least one device, in particular a battery cell of a battery, for a motor vehicle to be cooled as efficiently as possible in the simplest and most cost-effective manner possible.

This object is achieved by a method, a cooling device and a battery having the features according to the respective independent patent claims. Advantageous configurations of the invention are the subject matter of the dependent patent claims, the description and the figures.

In a method according to the invention for operating a cooling device for cooling at least one device, in particular a battery cell of a battery, for a motor vehicle, the cooling device has at least one cooling channel through which a coolant can flow, which has a cooling side facing the at least one device, which is at least partially flexible is trained. In this case, the cooling device is controlled in such a way that the at least one cooling channel is flowed through by a coolant with a definable operating pressure in a specific operating mode. Furthermore, the cooling device is controlled in a time-limited calibration mode that differs from the specific operating mode in such a way that the coolant flows through the at least one cooling channel at a definable calibration pressure that is greater than the operating pressure.

The invention is based on the finding that precisely when a material is used for the cooling side that is flexible but only slightly or not elastic, it can happen over time that the cooling side, which originally, for Example in a specific plant area of the cooling side, with one side of the Bat tery cell was brought to the plant, no longer comes completely to the plant. In addition, cooling sides, which should be at least partially flexible, are usually very thin-walled, so that, for example, switching off the cooling function and an associated reduction in the operating pressure can be sufficient to change the surface geometry of the cooling side, which means that it is no longer complete comes into contact with the battery cell as intended. Even during the initial calibration of the cooling device, for example during production of the battery, it may be that the normal operating pressure is not sufficient to optimally bring the cooling side into contact with the at least one battery cell. However, an increase in the operating pressure would result in enormous energetic disadvantages of a high pump pressure, would also require a more complex design of the coolant pump in some cases and an overall more robust design of the entire coolant circuit in relation to an increased pressure. The time-limited calibration mode, on the other hand, can advantageously be used to temporarily increase the coolant pressure to the predeterminable calibration pressure in order to bring the cooling side into contact with the at least one battery cell and thereby compensate or iron out any deformations of the cooling side. You can imagine this, for example, similar to the abrupt inflation of a crumpled or dented metallic beverage can. After this inflation, the pressure can be reduced again to the normal operating pressure, while the cooling side, however, at least essentially retains its geometric shape, which it has achieved through inflation, at least for a certain time. By temporarily increasing the coolant pressure, which can also be carried out cyclically, as provided by the calibration mode, it is advantageously possible to carry out a thermal calibration of the cooling device both in production and in customer service or even while driving. Since the calibration mode is limited in time, energy disadvantages of a fundamentally higher pump pressure are advantageously avoided. A correspondingly complex design of the entire coolant circuit is also not required, as would be the case if the coolant circuit as a whole had to permanently withstand such a high coolant pressure. Such a calibration or recalibration can also be carried out at very long time intervals, for example once or twice a year, which is therefore very rare and therefore does not particularly stress the coolant system mechanically. Nevertheless, this is already sufficient to optimize the efficiency of the thermal connection of the cooling device to the at least one battery cell. By inflating the at least one cooling channel with the definable calibration pressure, it is also possible that fewer or no gap fillers have to be used during production, since the gap width between the at least one cooling channel and the at least one battery cell can be additionally reduced as a result. In this way, better cooling can also be achieved in principle.

Although the method described and the cooling device explained in more detail below are particularly advantageous for cooling one or more battery cells of a battery, in particular a high-voltage battery, of a motor vehicle, the invention and its embodiments can not only provide a cooling function but also a heating function in addition or as an alternative and on the other hand, the at least one device can also represent a device that is different from a battery and/or a battery cell, in particular an electrical or electronic device. Consequently, the component to be cooled or also to be heated can also be something other than a battery cell, for example power electronics or a control unit or control units. The invention and its embodiments are therefore also suitable for temperature control of other devices, in particular outside of the motor vehicle sector. Although the embodiments and examples described in more detail below relate mainly to the cooling of at least one battery cell, the examples and embodiments described can also be used analogously without restriction for devices other than battery cells.

As mentioned, the at least one device is preferably designed as a battery cell of a battery. The battery cell of the battery can be designed as a lithium-ion cell, for example. Furthermore, the battery of the motor vehicle is preferably designed as a high-voltage battery and includes a number of battery cells. In particular, the battery can include multiple battery modules, which in turn have multiple battery cells. The battery cells can be designed as prismatic battery cells, round cells or pouch cells, for example. Furthermore, the cooling device can be designed, for example, with a cooling plate or a cooling floor, which has the at least one cooling channel. Such a cooling plate can accordingly also comprise a number of cooling channels. For example, such a cooling plate can be designed as a roll-bond cooling plate, which comprises two thin metal sheets joined together by means of a roll-bonding process, between which the cooling channels are formed. The flexible design of at least part of the cooling side is provided by appropriate design of these metal sheets puts. The calibration pressure can be measured in such a way that it exceeds the plastic material limit of the cooling side. However, the cooling device does not necessarily have to have a cooling plate, but can, for example, also be designed as a cooling pad or the like. The at least one cooling channel can also be arranged on an underside of the at least one battery cell in relation to an intended installation position of the battery in the motor vehicle or between two battery cells or battery modules. For this purpose, the at least one cooling channel can run horizontally or also vertically. In principle, there are generally no limits to the design options for the at least one cooling channel or the cooling device.

Furthermore, the specific operating mode represents a normal cooling mode for cooling the at least one battery cell of the battery, such as is activated, for example, when the battery is being charged or while the motor vehicle is being driven. The calibration mode, on the other hand, as already described above, is only used very rarely, at intervals of several weeks, months or even years.

The coolant can generally be a liquid and/or gaseous coolant. The coolant preferably comprises water, in particular for the most part. This enables a particularly simple and cost-effective design of the cooling device.

In a further very advantageous embodiment of the invention, the at least one cooling channel in the calibration mode is flowed through by the coolant at the predeterminable calibration pressure such that in the event that the cooling side is not in contact with the at least one device, in particular the battery cell, in a specific contact area of the cooling side is applied, is brought into contact with the at least one device, in particular the battery cell, in the contact area by the calibration pressure, in particular with the coolant flowing through the cooling channel at an operating pressure of less than 1.5 bar in the operating mode, and with a calibration pressure in the calibration mode in the range between 2.0 bar and 4.0 bar inclusive, preferably between 2.5 bar and 3.5 bar. The calibration pressure is therefore about one to three bar above the normal operating pressure, but lower than the test pressure of the cooling plate or the cooling system. This has the great advantage that such calibration pressures are particularly well suited to inflating or inflating a very thin-walled cooling side without damaging it. The calibration pressure therefore advantageously makes it possible for a specific contact area, which should ideally come into contact with the battery cell, to also be brought into contact if it does not or no longer does so. This is a simple way of optimizing the cooling performance.

In a further advantageous refinement of the invention, the calibration mode is carried out for a predefined, limited period of time which is less than ten minutes, in particular less than five minutes. In particular, a relatively short pressure pulse is already sufficient to enable efficient inflation or pumping of the at least one cooling channel. Such a pressure pulse can also only be in the range of seconds or in the low single-digit range of minutes. Preferably, the predetermined period of time is measured to be significantly shorter than five minutes, for example the period of time can also be between five seconds and 120 seconds inclusive, or only between five seconds and 60 seconds inclusive. Such a short execution of the calibration mode is particularly energy-efficient and gentle on components.

In a further very advantageous embodiment of the invention, thermal calibration is carried out according to the calibration mode during production of the at least one device, in particular the battery, and/or during customer service or during operation of the motor vehicle in which the cooling device is used. During the production of the battery, such a thermal calibration can be used to initially minimize the gap width between a cooling plate providing the at least one cooling channel and the at least one battery cell, so that either no thermal compound at all or only very little thermal compound is used to fill such a gap . The thermal resistance between the at least one battery cell and the at least one cooling channel can be minimized as a result. In addition, costs and weight can be further saved by saving the heat-conducting compound. If the cooling side deforms over time and, for example, no longer comes into contact with the battery cell as intended in a certain area, this can be done by recalibrating, for example in the event of customer service, or during normal driving. In the case of customer service or repairs, there is also the possibility, for example, of exchanging a battery module for a new battery module and then optimally adapting the at least one cooling channel or its cooling side to the geometry of this new battery module by executing the calibration mode. This advantageously allows the air gap between the cells and the at least one cooling channel to be recalibrated. This means that the cooling plate does not always have to be replaced in the event of a repair. The cooling plate can be easily contacted with the new module and thermally calibrated using the calibration mode. It is also conceivable that the calibration mode is also carried out during normal vehicle operation, for example as a function of predetermined events or at fixed time intervals. A predetermined event can be, for example, a longer standstill time of the vehicle, in particular when the outside temperatures are very low. Touching down and settling effects due to bending or torsion within the battery can also result in the above-mentioned specific contact area of the cooling side no longer being in proper contact with the at least one battery cell. This can also be remedied by repeated, for example regular, execution of the calibration mode during vehicle operation. This means that numerous application options are advantageously provided in order to use the calibration mode advantageously and thus maximize the efficiency of the cooling device.

In a further advantageous embodiment of the invention, the cooling device for executing the calibration mode is coupled to a vehicle-external pressurization device that generates the calibration pressure during the calibration mode, and/or the cooling device generates the calibration pressure during the calibration mode.

In other words, the cooling device itself does not have to be designed to provide the increased calibration pressure, but this can optionally also be done by connecting a vehicle-external pump or another vehicle-external pressurization device. This variant is particularly advantageous for carrying out the calibration mode during production or in the event of customer service. This therefore also requires no special training of the pump of the coolant circuit of the motor vehicle. In this case, for example, the external pressurization device can be connected to an external connection device for coupling to the cooling device, in particular to the coolant circuit of the cooling device, in particular to the coolant circuit of the cooling device, and this can generate an increased coolant pressure for carrying out the calibration mode. After the calibration mode has ended, the external pressurization device can again be decoupled from the cooling device. Alternatively, however, it is also conceivable that the cooling device itself is designed to generate an increased calibration pressure, for example using a coolant pump of the motor vehicle. This has the great advantage that the calibration mode can then be carried out at any time, for example even during normal driving operation, and the motor vehicle does not necessarily have to go to a workshop or customer service for this.

In a further advantageous embodiment of the invention, a leak test is carried out in the calibration mode, according to which it is checked whether there is a leak in the cooling channel. This makes it possible to detect micro-leaks in particular, which would not be detectable under normal operating conditions, but also larger leaks. Leaks in the cooling system can also generally be detected by monitoring the cooling water level and if this drops this indicates a leak. In the event of micro-leakage, however, the cooling water level drops so slightly that this is usually not detectable. Carrying out a leak test during the calibration mode has several advantages at the same time: On the one hand, the excessive pressure, namely the calibration pressure, can force coolant out of very small microcracks in the cooling system, which could then still be registered by a drop in the cooling water level. Alternatively, there is also the possibility of detecting such microcracks based on the reduced coolant pressure that occurs when coolant leaks out. In this way, microcracks in the cooling system can also be detected and repaired at an early stage and/or other measures can also be taken temporarily. For example, it can be provided that the cooling water reservoir is filled or topped up with another liquid present in the motor vehicle, in particular also mostly water, from another reservoir if the level drops too much. This can be, for example, wiper water, which is usually used for the windshield wiper system in the front and rear area. If the motor vehicle is, for example, a hybrid vehicle with an internal combustion engine, it can also be water from a water tank for water injection in accordance with the EU7 exhaust emission standard. If the motor vehicle has a fuel cell, for example, then the motor vehicle typically also includes a water collecting container for the fuel cell. Water that has been separated into such a water collecting tank can also be used as a coolant. In this way, temporary emergency cooling can advantageously also be provided in the event of a leak, for example until the vehicle has reached the nearest workshop.

Furthermore, the invention also relates to a cooling device for a motor vehicle for cooling at least one battery cell of a battery of the motor vehicle, wherein the cooling device has at least one cell through which a coolant can flow Has a cooling channel, which has a cooling side for cooling the at least one battery cell, wherein the cooling side is at least partially flexible, and wherein the cooling device is set up in such a way that the at least one cooling channel is flowed through by a coolant with a specifiable operating pressure in a specific operating mode . The cooling device is set up in such a way that the coolant can flow through the at least one cooling channel at a definable calibration pressure that is greater than the operating pressure in a time-limited calibration mode that differs from the specific operating mode.

The advantages mentioned for the method according to the invention and its configurations apply in the same way to the calibration device according to the invention.

Although the cooling device according to the invention and its embodiments are preferably used for cooling at least one battery cell of a battery, it is nevertheless also suitable and usable for cooling or heating another device, as already described above.

The invention also includes developments of the cooling device according to the invention, which have features as have already been described in connection with the developments of the method according to the invention. For this reason, the corresponding developments of the cooling device according to the invention are not described again here. Conversely, the further developments of the cooling device according to the invention, explained in more detail below, also enable the further development of the method according to the invention through further corresponding method steps.

In an advantageous embodiment of the cooling device according to the invention, the cooling side is made of a metal or an alloy. In principle, the cooling side can also be formed from a plastic or plastic composite. However, a metal or an alloy has the great advantage that a significantly higher thermal conductivity of the cooling side can be provided as a result. Although the cooling side has a thickness that, as explained in more detail below, is significantly less than one millimeter, the use of a plastic film with such a thickness as the cooling side would already result in a significantly increased thermal resistance compared to a cooling side made of metal or a Alloy are provided. Accordingly, a significantly higher efficiency of heat dissipation can be provided by a cooling side made of a metal or an alloy. Furthermore, it is preferred that the cooling side is designed in such a way that when changing from the calibration mode to the specific operating mode, it retains its geometric shape, at least essentially, and at least for a specific period of time. In other words, the cooling side is inflated when changing from operating mode to calibration mode, while the cooling side remains inflated when changing from calibration mode to operating mode, i.e. when changing from calibration mode to operating mode, the volume of the at least one cooling channel is at least not noticeably reduced. This can also be implemented in a particularly simple manner by means of a metal cooling side, since a cooling side made of metal or an alloy can have high dimensional stability even with a very thin-walled design and low operating pressure.

In a further very advantageous embodiment of the invention, the cooling side has a wall thickness in the range between 0.2 millimeters and 0.5 millimeters inclusive. Such a thin wall thickness is particularly suitable for providing sufficient flexibility to inflate the cooling side. In addition, a cooling side with such a wall thickness is sufficiently robust to withstand a calibration pressure in the range between two and four bar.

In a further advantageous embodiment of the invention, the cooling device has a cooling plate which is designed as a roll-bond cooling plate and which provides the cooling channel. In particular, the cooling plate can also provide several cooling channels or a winding cooling channel.

The design of the cooling plate as a roll-bond cooling plate is particularly advantageous in order to provide a sufficiently thin-walled metal cooling plate in a simple and cost-effective manner.

Furthermore, the invention also relates to a battery with a cooling device according to the invention or one of its configurations. Here, too, the advantages mentioned in connection with the cooling device according to the invention and the method according to the invention apply in the same way to the battery according to the invention.

The battery is also preferably embodied as a high-voltage battery of a motor vehicle and in particular comprises a number of battery modules, each with a number of battery cells.

In addition, a motor vehicle with such a battery should also be regarded as belonging to the invention. The motor vehicle according to the invention is preferred as a motor vehicle, in particular designed as a passenger car or truck, or as a passenger bus or motorcycle.

The invention also includes the combinations of features of the described embodiments. The invention also includes implementations that each have a combination of the features of several of the described embodiments, unless the embodiments were described as mutually exclusive.

• 1 eine schematische Querschnittsdarstellung einer Batterie mit einer Kühleinrichtung vor einer thermischen Kalibrierung gemäß einem Ausführungsbeispiel der Erfindung;
• 2 eine schematische Darstellung der Batterie mit der Kühleinrichtung aus 1 während einer thermischen Kalibrierung; und
• 3 eine schematische Querschnittsdarstellung der Batterie mit der Kühleinrichtung aus 1 und 2 nach der Durchführung der thermischen Kalibrierung gemäß einem Ausführungsbeispiel der Erfindung.

Exemplary embodiments of the invention are described below. It shows:

• 1 a schematic cross-sectional view of a battery with a cooling device before a thermal calibration according to an embodiment of the invention;
• 2 a schematic representation of the battery with the cooling device 1 during a thermal calibration; and
• 3 a schematic cross-sectional view of the battery with the cooling device 1 and 2 after performing the thermal calibration according to an embodiment of the invention.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that are to be considered independently of one another and that also develop the invention independently of one another. Therefore, the disclosure is also intended to encompass combinations of the features of the embodiments other than those illustrated. Furthermore, the described embodiments can also be supplemented by further features of the invention that have already been described.

In the figures, the same reference symbols designate elements with the same function.

1 shows a schematic representation of a battery 10 with a cooling device 12 in a cross section according to an embodiment of the invention. The battery 10 has, in particular, a plurality of battery cells 14, examples of which are shown in 1 four are shown. Furthermore, the battery cells 14 are designed as prismatic battery cells 14 in this example, but can also be designed as pouch cells or round cells. The cooling device 12 comprises at least one cooling channel 18 through which a cooling medium 16 can flow. Two such cooling channels 18 are shown in this example. In principle, the cooling device 12 can have any configuration and can also be arranged on any side of a battery cell 14 . In the present example, the cooling channels 18 are provided by a cooling plate 20 which is designed in particular as a roll-bond cooling plate 20 . The cooling channels 18 are correspondingly formed by two thin metal sheets 22, 24 connected to one another by means of a roll-bonding process. Furthermore, the cooling plate 20 is preferably made of metallic material, but can generally also be made of plastic or a plastic composite. The side 26 facing the battery cells 14 is referred to here as the cooling side 26 and is provided in this example by the sheet metal 22 of the cooling plate 20 facing the battery cells 14 . This cooling side 26 is designed to be flexible, at least in certain areas. This means that this cooling side 26 can be deformed when a corresponding force or pressure is applied. In this case, the cooling side 26 does not necessarily have to be elastic. The cooling side 26 preferably even has extremely low elasticity. The reason for this will be explained in more detail later. These properties can be provided in a particularly simple manner by a thin sheet metal 22, for example with a wall thickness d in the range between 0.2 and 0.5 millimeters. On the other hand, the sheet metal 24 facing away from the battery cells 14 can optionally also be made thicker and does not necessarily have to provide the same flexibility as the cooling side 26. Nevertheless, this second sheet metal 24 can also be made with the same wall thickness d. On the underside, the cooling plate 20 can also be supported by a corresponding support device, for example a housing bottom of a housing of the battery 10, which is not explicitly shown in the present example. In order to cool the battery cells 14, the cooling ducts 18 are used during normal operation, i.e. for example in a specific operating mode B, which is present in 1 is illustrated, in particular at a first time t1, flows through the coolant 16 with a first coolant pressure p1, which represents an operating pressure. This operating pressure p1 is preferably less than 1.5 bar and is preferably in the range of approximately one bar.

In order to maximize the cooling effect, it is advantageous if there are as few gaps as possible, in particular no air gaps, between the cooling plate 20 and the battery cells 14, in particular their undersides 14a. To improve the thermal connections, a heat-conducting compound, also frequently referred to as a gap filler, can optionally be provided between the undersides 14a of the respective battery cells 14 and the cooling plate 20 . Due to the flexible design of the cooling side 26, it can also advantageously be done without such a heat-conducting compound or with one accomplish extremely small amount of thermal compound to bring this cooling side 26 with the undersides 14a of the battery cells 14 in conditioning. In particular, this can be accomplished solely by the coolant pressure of the coolant 16 . The normal operating pressure p1 is normally sufficient for this. However, there can still be various reasons why, under certain circumstances, the cooling side 26, despite its flexible design, does not come to rest ideally on the undersides 14a of the battery cells 14, as is shown schematically in 1 is shown. Examples of this can be, for example, that there are settling effects after the battery assembly, in particular due to bending or torsion within the battery, which means that there is no longer an ideal contact with the battery cells 14 in places. Long standing times of the motor vehicle in winter or other aging-related influences can also have such an effect. This can now advantageously be avoided or rectified in that a thermal calibration or recalibration can be carried out. this is in 2 schematically illustrated.

while showing 2 turn the battery 10 and the cooling device 12 off 1 , but now during a calibration mode K at a time t2, which after in 1 shown time t1 is. During this calibration mode K, the coolant pressure is temporarily increased to a calibration pressure p2. This is, for example, in the range between two and four bar. Due to the flexible design of the cooling side 26, the cooling channels 18 are inflated accordingly, whereby the cooling side 26 nestles all the more against the battery cells 14, in this example on their undersides 14a, whereby gaps and unevenness are compensated for. Such an application of pressure with an increased calibration pressure p2 preferably takes place for a relatively short time, for example in the range of one to two minutes or even in the range of a few seconds. This pressure increase does not necessarily have to be able to be accomplished by the cooling device 12 itself, but can also be performed by a vehicle-external pressurization device that is coupled to the cooling device 12 at a connection device of the cooling device 12 . Such a temporary increase in pressure allows the calibration to be carried out in a particularly gentle manner on the components and is also particularly energy-efficient, since the cooling device 12 does not have to be operated permanently at such a high pressure. The pressure can then be reduced back to the normal operating pressure p1, as is shown schematically in 3 is shown. 3 shows the battery 10 with the cooling device 12 1 and 2 again in the specific operating mode B at a third time t3 after the calibration. As already mentioned above, it is preferable for the cooling side 26 to be designed with as little elasticity as possible. The reason for this is that the expanded shape of the cooling side 26 is then retained even after the coolant pressure has been reduced to the operating pressure p1. In other words, the cooling device 20 can now continue to be operated with the reduced operating pressure p1, which is particularly gentle on components and energy-efficient, but the cooling plate 20, in particular the cooling side 26, remains in the inflated form, at least for a while. Experience has shown that such time periods can extend over several weeks, in particular months or even years. Accordingly, it is sufficient to carry out such a thermal calibration extremely infrequently, for example once a year, in order to optimize the cooling effect and achieve a new calibration.

The calibration described can be carried out in different situations and can be advantageous. On the one hand, such a calibration can be carried out during the production of the battery, ie when the battery 10 is assembled for the first time. In this case, if the cooling plate 20 is inflated with water pressure, less gap filler is used and better cooling can be achieved. Such a calibration can also be carried out in the case of customer service, for example when repairing the battery. For example, a battery module can also be exchanged in this way and the cooling plate 20 can then be easily adapted to the geometry of the new battery module by carrying out such a thermal calibration. However, such a calibration can also be carried out while the vehicle is in operation. A leak test can also be carried out in this way, for example, in a particularly advantageous manner. Overall, cyclic movements can be generated by the cooling device 12 or the cooling plate 20 over the running time of the battery 10 in order to optimize the shaping of the cooling side 26 on the battery cells 14 and to improve the service life.

Overall, the examples show how the invention can provide a calibration function for a cooling plate that increases the cooling efficiency in a simple way by cyclically pumping up the cooling plate in production, in vehicle operation and/or in customer service to calibrate the cooling system surfaces. In this way, an ideal contact with the surface to be cooled can be created in a particularly component-friendly and energy-saving manner and the thermal connection can be optimized as a result.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102018216713 A1 [0003]
• US 2013/0250512 A1 [0003]
• US4938279A [0003]

Claims (10)

Method for operating a cooling device (12) for cooling at least one device (10, 14) for a motor vehicle, the cooling device (12) having at least one cooling channel (18) through which a coolant (16) can flow, which is one of the at least one device ( 10, 14) facing the cooling side (26), which is at least partially flexible, the cooling device (12) being controlled in such a way that the at least one cooling channel (18) in a specific operating mode (B) from a coolant (16) with a predeterminable operating pressure (p1), characterized in that the cooling device (12) is controlled in a time-limited calibration mode (K) that differs from the specific operating mode (B) in such a way that the at least one cooling channel (18) is filled with coolant (16) is flowed through with a definable calibration pressure (p2) which is greater than the operating pressure (p1). procedure after claim 1 , characterized in that the coolant (16) flows through the at least one cooling channel (18) in the calibration mode (K) at the predeterminable calibration pressure (p2) such that if the cooling side (26) is in a specific contact area of the cooling side (26) is not in contact with the at least one device (10, 14), in particular a battery cell (14) of a battery (10), is brought into contact with the device (10, 14) in the contact area by the calibration pressure (p2). , in particular wherein in operating mode (B) the coolant (16) flows through the at least one cooling channel (18) at an operating pressure (p1) of less than 1.5 bar, and in calibration mode (K) at a calibration pressure (p2) im Range between 2.0 bar and 4.0 bar inclusive. Method according to one of the preceding claims, characterized in that the calibration mode (K) is carried out for a predetermined limited period of time which is less than ten minutes, in particular less than five minutes. Method according to one of the preceding claims, characterized in that a thermal calibration according to the calibration mode (K) is carried out during production of the device (10, 14), in particular a battery (10) and/or at customer service or when the motor vehicle is in operation becomes. Method according to one of the preceding claims, characterized in that the cooling device (12) for executing the calibration mode (K) is coupled to a motor vehicle-external pressurization device which generates the calibration pressure (p2) during the calibration mode (K), and/or the cooling device ( 12) generates the calibration pressure (p2) during the calibration mode (K). Method according to one of the preceding claims, characterized in that a leak test is carried out in the calibration mode (K), according to which it is checked whether there is a leak in the at least one cooling channel (18). Cooling device (12) for a motor vehicle for cooling at least one battery cell (14) of a battery (10) of the motor vehicle, the cooling device (12) having at least one cooling channel (18) through which a coolant (16) can flow, which has a cooling side (26) for cooling the at least one battery cell (14), the cooling side (26) being flexible at least in part, the cooling device (12) being set up in such a way that the at least one cooling duct (18) in a specific operating mode (B) of a coolant (16) with a definable operating pressure (p1) flows through it, characterized in that the cooling device (12) is set up in such a way that the at least one cooling channel (18) differs from the specific operating mode (B) in a time-limited calibration mode ( K) the coolant (16) can flow through at a definable calibration pressure (p2) which is greater than the operating pressure (p1). Cooling device (12) after claim 7 , characterized in that the cooling side (26) is made of a metal or an alloy, in particular wherein the cooling side (26) is designed in such a way that it changes its geometric shape when changing from the calibration mode (K) to the specific operating mode (B). maintained at least for a certain period of time. Cooling device (12) according to one of Claims 7 until 8th , characterized in that the cooling device (12) has a cooling plate (20) which is designed as a roll-bond cooling plate (20) and which provides the at least one cooling channel (18). Battery (10) with a cooling device (12) according to one of Claims 7 until 9 .

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