Method for producing a thermal interface in a battery for a motor vehicle and battery for a motor vehicle

Abstract

The invention relates to a method for producing a thermal interface in a battery for a motor vehicle, the method comprising: providing at least one battery module and at least one receiving structure having a receiving area, the receiving area having a heat transfer surface and being used to receive the battery module side of the battery module in an installation position; applying a heat conducting material to the heat transfer surface according to a predetermined dosage, the heat conducting material being used to fill a gap between the heat transfer surface and the battery module side; installing the battery module while filling the applied heat conducting material, the filled heat conducting material then filling the gap and forming a thermal interface between the battery module side and the heat transfer surface; wherein before applying the heat conducting material, at least one recess is produced in the receiving area with a volume coordinated with the predetermined dosage of the heat conducting material, the recess being used as a container for excess heat conducting material when filling the heat conducting material. The invention also relates to a battery for a motor vehicle.

Description

Technical Field

[0001] The invention relates to a method for producing a thermal interface in a battery for a motor vehicle and to a battery for a motor vehicle. Background Art

[0002] So-called thermal interface materials or gap fillers, also often referred to as heat-conducting materials, are often used in battery systems of motor vehicles for heat dissipation and for tolerance compensation when gaps are present. In order to ensure heat conduction within all tolerance ranges, such heat-conducting materials are generally metered to the largest possible gap size and thus usually to a relatively high degree of overfilling relative to the nominal tolerance and, above all, the minimum tolerance.

[0003] Batteries for motor vehicles usually include a plurality of battery modules, in which a plurality of battery cells are often combined. Such battery modules are received by a receiving structure, for example in the form of a battery frame or the like. Such a receiving structure can have a heat transfer surface, for example in the form of a partition as an intermediate layer, a cooling plate, another cooling structure or generally a heat sink, via which excess heat is to be dissipated from the battery cells and thus from the battery module to the battery's cooling system. Due to manufacturing tolerances, for example, different shapes and positions of the partitions, the battery frame, the lower side of the battery module and different positions of the connection points on the battery frame and the battery module occur for the battery.

[0004] Since a certain overfilling degree of heat-conducting material, i.e. in the form of thermal interface material or gap filler, often has to be tolerated, very high forces may occur during the installation of the battery module, especially during the positioning of the battery module, if the battery module is filled and the already applied heat-conducting material is displaced. In addition, it may also happen that very long process times have to be tolerated, since the filling of the already applied heat-conducting material can only be carried out very slowly in order to keep the forces occurring here low and not damage the structure, in particular the relevant battery module and the receiving structure for the battery module. When too little filling with heat-conducting material is carried out, i.e. when the gap to be filled is not sufficiently filled with heat-conducting material, there is a risk that the thermal properties of the associated cooling system are very poor. Therefore, insufficient dosing of heat-conducting material is also disadvantageous.

[0005] In addition, overfilling of heat-conducting materials results in high material input and thus high costs. This also represents a waste of resources and thus leads to a poor environmental balance. In addition, the heat-conducting materials commonly used have a density of more than 2 g / cm 3 The density of the fuel cell is therefore relatively high, that is to say it has a relatively high weight, which the vehicle concerned must also carry during its service life, which in turn has a negative impact on the energy balance of the motor vehicle. Summary of the invention

[0006] It is therefore an object of the present invention to provide a solution by means of which at least one thermal interface in a battery of a motor vehicle can be produced as efficiently as possible.

[0007] This object is achieved by a method for producing a thermal interface in a battery for a motor vehicle and a battery for a motor vehicle, which are provided by the invention.

[0008] In the method for producing a thermal interface in a battery for a motor vehicle according to the invention, at least one battery module and at least one receiving structure having a receiving area are provided, the receiving area having a heat transfer surface and being used to receive the battery module side of the battery module in a prescribed installation position. The battery module can, for example, have one or more battery cells that are electrically connected to each other, for example based on lithium ions. Other single cell technologies are of course also possible. The battery can, for example, be a high-voltage battery for an electrically driven motor vehicle. The receiving structure can, for example, be a battery frame or a similar component. The heat transfer surface can, for example, be a partition, a cooling plate or also other cooling structures or generally a heat sink.

[0009] A heat conducting material is applied to the heat transfer surface and / or the battery module side according to a predetermined dosage. The heat conducting material is used to fill a gap between the heat transfer surface and the battery module side, which is present in a prescribed installation position, and the battery module side can be received in a receiving area of ​​a receiving structure. The battery module is installed while filling the applied heat conducting material, after which the filled heat conducting material fills the gap and forms a thermal interface between the battery module side and the heat transfer surface.

[0010] Before applying the heat-conducting material, at least one recess is produced in the receiving area and / or in the battery module side with a volume coordinated with a predetermined dosage of the heat-conducting material, wherein the recess is used as a container for excess heat-conducting material when filling with the heat-conducting material. "Before applying" can, for example, mean that the recess is produced immediately when the receiving area and / or the battery module side is manufactured. However, it is also possible that the mentioned recess is also produced later. The battery module side can, for example, be a housing part of a battery module. The heat-conducting material is therefore used as a so-called gap filler or thermal interface material.

[0011] It is important for the method according to the invention that the aforementioned recess is arranged in the receiving area and / or in the battery module side, which recess serves as a container for excess heat-conducting material when filling with heat-conducting material. The arrangement and volume of the at least one recess are realized or predetermined in accordance with a predetermined dosage amount of heat-conducting material, so that an excessively high increase in force can be avoided when filling with the applied heat-conducting material with only minimal influence on the degree of wetting of the heat-conducting material. For example, it can be provided that the recess is designed to be relatively narrow, so that a particularly large heat transfer surface is also available for the actual heat transfer.

[0012] First, the at least one recess or also a plurality of recesses in the recess can be arranged in such a way that a short flow path for the corresponding flow front of the heat-conducting material can be ensured during the filling, in particular. By maintaining a short flow path at least until complete wetting of the heat transfer surface is achieved, it can be ensured that no excessive force occurs during the filling. As long as the actual gap between the heat transfer surface and the battery module side has been completely filled with heat-conducting material, the excess heat-conducting material can easily be offset into at least one recess or flow into the recess, which serves as a container for the excess heat-conducting material. Therefore, the drastic increase in force that is usually caused by overfilling the gap can be avoided. In addition, the recesses can also be made in such a way that air can be guided to the outside in a controlled manner through or via these recesses, so that air locks inside the heat-conducting material can be prevented.

[0013] Thus, by providing the at least one recess serving as a container for excess heat-conducting material, a so-called sharp increase in the holding force can be avoided when filling the applied heat-conducting material, in particular for large-area applications. Furthermore, it can also be prevented that the heat-conducting material flows out uncontrolled at specific locations of the battery during filling or that it is distributed uncontrolled. Furthermore, as mentioned, it is also possible to prevent air locks within the heat-conducting material. The use of expensive measuring systems, for example for tolerance-controlled coating methods, for which, for example, the gap dimensions are measured beforehand, can be dispensed with.

[0014] The present invention is based in particular on the recognition that the heat-conducting material used as a filler in batteries or battery systems is usually quite viscous and therefore difficult to fill due to the relatively high filler content for heat conduction. For example, during filling, the coating shape of the heat-conducting material can be selected, which ensures a favorable initial distribution of the heat-conducting material, for example on a heat transfer surface. As long as the heat-conducting material has not yet merged during filling and there is therefore a considerable number of flow fronts, the heat-conducting material can usually still be filled with less force, but in the further process the heat-conducting material is to be filled in full, the flow fronts between the battery module side and the heat transfer surface converge and thus annihilate each other. In this case, a very long flow path is left for the heat-conducting material to the outside, so that a high force must be applied for further filling. The at least one recess serving as a container for excess heat-conducting material is provided, whereby this mentioned increase in force can be prevented as much as possible.

[0015] Thus, even for large-area applications with regard to the heat transfer surface and the battery module side, the occurrence of forces which could otherwise lead to damage to the battery structure, such as individual battery cells, or also to damage to the cooling device, can be prevented when filling the applied heat-conducting material. Thus, deformations, such as bending in the middle region of the heat transfer surface, which would lead to uneven layer thicknesses in the heat-conducting material, can also be avoided in the method according to the invention. As a result, the thermal resistance in the thermal interface can be kept low.

[0016] The present invention is based in particular on the recognition that, as soon as the filling material completely fills the gap between the battery module side and the heat transfer surface before reaching the prescribed installation position when filling the heat-conducting material, the force for reaching the prescribed installation position, i.e. the force still to be applied for further filling of the heat-conducting material, increases very sharply. This can hardly be influenced in terms of process technology. Different coating patterns and different set speeds in the coating of the heat-conducting material show an influence on the generation of forces, especially within the technically significant scope, only when the heat-conducting material flows, i.e. when a flow front is also constructed by the selected coating pattern, but not when overfilling of the area between the heat transfer surface and the battery module side occurs. The influence of temperature also does not show a significant influence, although higher temperatures lead to lower viscosities and thus to better flowability of the heat-conducting material used as a gap filler.

[0017] Therefore, in particular, by means of the arrangement according to the invention of the at least one recess, it is possible to prevent excessively high forces from occurring when filling the applied heat-conducting material until the intended installation position of the battery module is reached, which could, for example, deform the battery module and / or the heat transfer surface.

[0018] A possible embodiment of the present invention provides that the metering amount is predetermined in such a way that after the filling of the heat-conducting material, the gap is completely filled with the heat-conducting material while making maximum use of the tolerance range associated with the gap volume of the gap. The tolerance range associated with the gap volume can be generated, for example, by the dimensional tolerances and position tolerances of the individual components of the battery, first of all the battery module and the receiving structure. Therefore, in other words, the metering amount is predetermined in such a way that it is at least so high that after the filling of the heat-conducting material, the gap is completely filled with the heat-conducting material for the maximum possible gap volume of the gap. That is, due to manufacturing tolerances, position tolerances, etc., it may occur and it is also permissible that the heat transfer surface and / or the battery module side, for example, has a certain waviness, there are certain position tolerances in terms of the connection points, etc. For example, the metering amount can be predetermined in such a way that even for the maximum possible gap height and thus for the maximum possible gap volume of the gap, the gap is completely filled with the heat-conducting material after the filling of the heat-conducting material. It can also be provided that the metered amount is predefined with a certain excess so that, when the tolerance range associated with the gap volume of the gap is maximally utilized, the gap is completely filled with the heat conducting material after filling with the heat conducting material and a portion of the heat conducting material also flows into the at least one recess serving as a container. This ensures that the best possible wetting of the heat transfer surface and the battery module side is achieved.

[0019] Another possible embodiment of the invention provides that the arrangement of the recesses is predetermined in coordination with a predetermined application pattern of the heat conducting material. This allows particularly short flow paths to be ensured with respect to the respective flow fronts of the heat conducting material when filling with the heat conducting material. This ensures that the smallest possible forces occur when filling with the applied heat conducting material until the intended installation position of the battery module is reached.

[0020] According to another possible embodiment of the present invention, it is provided that the coating diagram is provided with a plurality of lines extending side by side of the heat-conducting material, wherein a plurality of recesses in the recesses are made as grooves extending parallel to the provided lines. In other words, it is therefore possible that the recesses are made in the form of grooves or similar structures. The grooves or recesses can be constructed so that they can also be vented to the outside during the filling of the heat-conducting material. This can prevent the air plug inside the heat-conducting material from being contained, which would otherwise increase the thermal resistance in the manufactured thermal interface. For example, it is possible that the coating diagram is provided with a plurality of lines or welds extending side by side in parallel of the heat-conducting material, wherein in this case the recesses are arranged so that these recesses always alternate with the linear coating diagram in the prescribed installation position of the battery module. This can achieve a particularly short flow front with the advantages mentioned above.

[0021] Another possible embodiment of the invention provides that the coating pattern provides a plurality of points of the heat conducting material arranged side by side, wherein a plurality of the recesses between the provided points are produced as depressions. In other words, it is also possible that the coating pattern provides a dot screen for the heat conducting material. The aforementioned recesses can then be provided in the corresponding gaps of the dot screen, which recesses can be designed as depressions. The alternating arrangement of the aforementioned depressions and points of the heat conducting material also serves to produce a short flow front with the advantages already mentioned above.

[0022] Another possible embodiment of the invention provides that at least one part of the receiving structure and at least one recess in the receiving region are produced by means of an extrusion process. The heat transfer surface can belong, for example, to a cooling plate, which can be a component of the receiving structure. The cooling plate can be produced, for example, in the form of an aluminum extruded profile. The individual cooling channels of the cooling plate can be produced very easily, wherein the at least one recess in the receiving region can also be produced very easily.

[0023] An alternative possible embodiment of the invention provides that the at least one recess is produced by means of a stamping process. For example, it is possible that at least one part of the receiving structure and / or the battery module side is produced by deep drawing. During the deep drawing process or a subsequent process, the aforementioned stamping process can be provided for producing the at least one recess. In this way, a concave-shaped recess or a plurality of concave-shaped recesses can be produced very easily.

[0024] According to another possible embodiment of the present invention, it is provided that the recess in the battery module side is made in such a way that it extends into at least one gap between adjacent single cells of the battery module. The battery module side can, for example, be a component of a separate housing module, which surrounds the mentioned single cells, and the single cells themselves can have their own single cell housing. It is also possible that the corresponding single cell housings of the adjacent single cells are components of the battery module side. Therefore, in principle it is possible that the battery module has an open structure, which includes at least one recess, which extends into the gap between adjacent single cells of the battery module. In this way, the at least one recess can also be realized very easily on the battery module side. Firstly, the single cell gaps that are already present can be effectively utilized here to provide the mentioned container or additional space for accommodating excess heat-conducting material.

[0025] Another possible embodiment of the present invention provides that the depth of at least one recess is greater than the width and / or the depth is greater than the length. Thus, the area for heat transfer is lost particularly little and nevertheless can accommodate enough redundant heat-conducting material at the same time. The width and / or length of the recess can be selected so that the heat-conducting material can flow or be squeezed into the recess without a significant pressure increase under the premise of matching the viscosity of the heat-conducting material. It is also possible that the recess starts from an opening-the heat-conducting material can flow into the recess through the opening-and widens as the depth of the recess increases. Thus, a particularly large container can be provided, wherein a relatively small area for heat transfer is lost at the same time due to a relatively small opening. It is also possible that the opening-the heat-conducting material can flow into the recess through the opening-has a cross-section smaller than the maximum cross-section of the recess. For example, the recess can also be constructed in a drop shape. In this case, a good ratio between the volume of the recess and the area still used for heat transfer is also obtained. It is also possible to predetermine a certain ratio between the area of ​​the heat transfer surface and the volume of the at least one recess or the total volume of all recesses (if a plurality of recesses are present).

[0026] The battery for a motor vehicle according to the invention comprises at least one battery module and at least one receiving structure having a receiving area, the receiving area having a heat transfer surface, in which the battery module side of the battery module is received in a prescribed installation position. In addition, the battery comprises a heat-conducting material, which fills the gap between the heat transfer surface and the battery module side and forms a thermal interface between the battery module side and the heat transfer surface. The receiving area and / or the battery module side have at least one recess serving as a container for excess heat-conducting material. The aforementioned embodiments of the method according to the invention can also be embodiments of the battery or embodiments derived therefrom.

[0027] Further possible advantages, features and details of the invention are apparent from the following description of a preferred exemplary embodiment and with the aid of the drawings. The features and feature combinations mentioned above in the description and the features and feature combinations shown below in the description of the figures and / or in the figures themselves can be used not only in the respectively described combination but also in other combinations or alone without departing from the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In the attached picture:

[0029] Figure 1 A schematic cross-sectional view of a cutout of a battery for a motor vehicle is shown, the battery having a battery module arranged on a receiving structure, wherein a thermally conductive material serving as a thermal interface material or gap filler is arranged between the battery module and the receiving structure;

[0030] Figure 2 A schematic diagram is shown showing a packing of thermally conductive material disposed between the battery module and the receiving structure, the receiving structure being bent due to the packing; and

[0031] Figure 3 Another schematic diagram shows the process of filling the heat conducting material, wherein a plurality of recesses are provided inside the receiving structure, and the recesses are used as containers for receiving excess heat conducting material.

[0032] In the figures, identical or functionally identical elements have been provided with the same reference symbols. DETAILED DESCRIPTION

[0033] A battery 10 for a motor vehicle is partially shown in a schematic side view. Figure 1. The battery 10 can have a plurality of battery modules 12, wherein only one of the battery modules 12 is schematically shown here. The battery module 12 can, for example, include a plurality of lithium-ion cells connected to one another, which are arranged in a housing of the battery module 12, which is not shown in detail. In addition, a heat transfer surface 14 can be seen, which belongs to a receiving structure for receiving the battery module 12, which is not indicated in detail here. The heat transfer surface 14 can be, for example, a partition or also a housing side with a heat sink or a cooling plate.

[0034] In the proper installation position of the battery module 12, a gap (not indicated in detail here) is produced between the lower side 16 of the battery module 12 and the heat transfer surface 14, which gap is filled as much as possible with a heat conducting material 18. The heat conducting material 18 is a thermal interface material or a so-called gap filler. The heat conducting material 18 is used to ensure the best possible thermal connection and thus the heat transfer from the battery module 12 to the heat transfer surface 14. For this purpose, it is particularly important to fill the aforementioned gap between the lower side 16 of the battery module 12 and the heat transfer surface 14 as much as possible without air locks.

[0035] For production reasons, it is generally not always possible to produce the battery modules 12 and in particular also the heat transfer surfaces 14 in exactly the same manner. Therefore, certain tolerances are already predetermined or permitted, also for cost reasons, within which fluctuations in size, position and shape are permitted for the battery modules 12 and the heat transfer surfaces 14. A tolerance range 20 for the shape of the bottom side 16 of the battery module 12 is schematically indicated here. A tolerance range 22 for the shape of the heat transfer surface 14 is also schematically indicated.

[0036] Thus, different corrugations or cambers can occur on the underside 16 and on the heat transfer surface 14, which can occur purely for manufacturing reasons and are also permissible within tolerance ranges 20, 22. Furthermore, corresponding connection points 24, 26 on the underside 16 of the battery module 12 and in the region of the heat transfer surface 14 are schematically outlined. Certain tolerance ranges 28, 30 are also permissible for the connection points 24, 26. In particular, certain position tolerances can be produced with respect to the connection points 24, 26.

[0037] Due to the different tolerance ranges 20, 22, 28, 30, certain clearances arise in the size and shape of the gaps mentioned, which are to be filled by means of the heat conducting material 18. A minimum gap height 32 and a maximum gap height 34 are schematically shown, which would result when all tolerances are exhausted. Depending on the minimum or maximum gap height 32, 34, a corresponding metering volume 36 also results for the smallest possible gap and a metering volume 38 for the maximum size of the gap.

[0038] exist Figure 2 , a schematic sectional view is shown of the filling of the heat conducting material 18 between the battery module 12 and the heat transfer surface 14. The heat transfer surface 14 may belong to a cooling plate, not indicated in detail, which has a plurality of cooling channels 40. In the case shown here, the heat conducting material 18 is applied to the heat transfer surface 14 in the form of a plurality of lines or weld beads. Thereafter, the battery module 12 is pressed or compressed in the direction of the heat transfer surface 14. As a result, the heat conducting material 18 is filled, which can be seen in this schematic diagram from the fact that the initially circular lines or weld beads, along which the heat conducting material was initially applied, are first flattened and then merged into a continuous block.

[0039] The greater the degree to which the heat conducting material 18 is filled, the greater the force that must be applied in order to move the battery module 12 further in the direction of the heat transfer surface 14. If, first of all, individual flow fronts of the heat conducting material 18 are no longer present, since the heat conducting material 18 merges into a single continuous mass, the force that must be applied in order to press the battery module 12 further in the direction of the heat transfer surface 14 increases significantly.

[0040] In this case, not only the battery module 12 but also the heat transfer surface 14 or the associated receiving structure (not shown in detail) which includes the heat transfer surface 14 may be deformed. The deformation or strain of the heat transfer surface 14 is only schematically shown here. The disadvantage of such a deformation is that the heat conducting material 18 does not have a uniform thickness after the setting process of the battery module 12. This has a negative effect on the discharge of excess heat from the battery module 12, in particular from the individual cells contained in the battery module 12, in the direction of the heat transfer surface 14.

[0041] exist Figure 3, the filling of the applied heat-conducting material 18 is again schematically shown. The receiving structure 42 mentioned here is now provided with a reference numeral for the first time. The receiving structure 42 includes the aforementioned receiving area 44 for the lower side 16 of the battery module 12. The receiving area 44 includes the heat transfer surface 14 mentioned above, wherein a plurality of recesses 46 have been made in the receiving area 44. These recesses 46 serve as containers for excess heat-conducting material that may remain when filling the heat-conducting material 18, which is applied linearly here again. The receiving structure 42 can include a cooling plate that is not indicated in detail, which is schematically outlined with the help of a plurality of cooling channels 40. For the sake of clarity, not all cooling channels 40 are provided with reference numerals.

[0042] The heat conducting material 18 is applied according to a predetermined dosage, in the example shown here, to the heat transfer surface 14. The heat conducting material 18 is applied linearly in the form of a plurality of weld beads extending parallel to one another, which extend into the plane of the drawing according to the present illustration. The individual recesses 46 are designed in the form of grooves or slots, which likewise extend into the plane of the drawing.

[0043] Combination Figure 1 It has already been explained that due to the different tolerance ranges 20, 22, 28, 30, a minimum gap height 32 or a maximum gap height 34 can occur, which is then accompanied by a corresponding metering volume 36, 38. Depending on the coordination of the tolerance ranges 20, 22, 28, 30, the gap between the heat transfer surface 14 and the bottom side 16 of the battery module 12 can be different.

[0044] Generally speaking, in the specified installation position of the battery module 12, the gap 48 is present between the heat transfer surface 14 and the lower side 16. The dosage of the heat-conducting material 18 is predetermined in such a way that even when the tolerance ranges 20, 22, 28, 30 are utilized to the maximum and for the respective maximum gap volume of the gap 48, the gap 48 is completely filled with the heat-conducting material 18 after filling. As can be seen here, the arrangement of the recesses 46 is carried out in coordination with the predetermined application pattern of the heat-conducting material 18. In the case shown here, the application pattern provides a plurality of lines of the heat-conducting material 18 running side by side, wherein a plurality of recesses in the recesses 46 are produced as grooves running parallel to the provided lines. The cooling channel 40 and the recesses 46 can also be produced, for example, in the process of an extrusion method.

[0045] The battery module 12 is installed by filling the applied heat-conducting material 18 by correspondingly exerting a force on the battery module 12. The battery module 12 is thus moved in the direction of the heat transfer surface 14. In this process, the individual lines or beads of the heat-conducting material 18 are pressed together. As a result, the individual lines or beads of the heat-conducting material 18 flow into each other and, when the battery module 12 is further pressed or moved in the direction of the heat transfer surface 14, excess heat-conducting material 18 flows into the recess 46 serving as a container.

[0046] “Excessive” means, in particular, that the proper installation position of the battery module 12 is reached and the gap 48 that then occurs is already completely filled with the heat conducting material 18 and that a certain amount of heat conducting material 18 always remains. The air enclosed within the heat conducting material 18 can also escape through the recess 46. For this purpose, the recess 46 can be extended in such a way that it opens into an opening (not shown in detail) through which the air can reach the outside.

[0047] Therefore, with Figure 2 Compared to the situation shown in FIG. 1 , the forces occurring when filling the applied heat conducting material 18 are much smaller in the situation shown here. Since the gap 48 is not reached until the intended end position of the battery module 12 is reached, in which the gap 48 is formed between the bottom side 16 and the heat transfer surface 14, any excess heat conducting material 18 can escape very easily into the recess 46. Even when individual lines of the heat conducting material 18 merge, in this case, there is no gap as in FIG. Figure 2 As shown in FIG, a large continuous mass of the heat conducting material 18 must be displaced at some point before the intended installation position is reached. Figure 2 Compared to the situation shown in , significantly lower forces occur. On the other hand, this can also prevent undesirable deformations of the battery module 12 and / or of the receiving structure 42 from occurring.

[0048] It is important that the arrangement of the recesses 46 is selected in coordination with the respectively selected application pattern of the heat conducting material 18 . Figure 3 The coating pattern shown in FIG. 1 with a plurality of lines of heat conducting material 18 running side by side is to be understood purely as an example. The same applies to the arrangement of the recesses 46 and the shape of the recesses 46. For example, it is also possible that the coating pattern provides a plurality of points of heat conducting material 18 arranged side by side, wherein a plurality of the recesses in the recesses 46 between the provided points are - in contrast to the present illustration - produced as depressions and not as continuous strips, grooves or the like.

[0049] Different application patterns can also be combined, so that the heat conducting material 28 can be applied not only in the form of lines or beads, but also in the form of spots. If all or some of the recesses 46 are made in the form of depressions, these recesses can be produced, for example, by means of a stamping process. This can be particularly suitable if at least a portion of the receiving structure 42 is produced by deep drawing.

[0050] In a case different from the present illustration, it is also possible to produce one or more of the recesses 46 on the lower side 16 of the battery module 12. This can be done as an alternative or in addition to the recesses 46 in the receiving area 44. For example, such recesses 46 on the lower side 16 can be produced in such a way that they extend into at least one gap between adjacent individual cells of the battery module 12. In this case, it is also possible to keep the forces that occur when filling the heat conducting material 18 low and at least partially in the receiving area 44. Figure 2 This is significantly reduced compared to the situation shown in .

[0051] Therefore, a sharp increase in the setting force when filling the heat conducting material 18 can be prevented by a corresponding advantageous arrangement of the recess 46. In addition, an uncontrolled outflow and distribution of the heat conducting material 18 can be prevented. In addition, depending on the design, the recess 46 can also help the air trapped during the filling of the heat conducting material 18 to escape.

[0052] List of reference numerals:

[0053] 10 Batteries

[0054] 12 battery modules

[0055] 14Heat transfer surface

[0056] 16 The lower side of the battery module

[0057] 18 Thermally conductive materials

[0058] 20 Tolerance range of the shape of the lower side of the battery module

[0059] 22 Tolerance range for the shape of the heat transfer surface

[0060] 24. Connection points of the battery module

[0061] 26 Connection points in the region of the heat transfer surface

[0062] 28 Tolerance range in the position of the connection points of the battery module

[0063] 30 Tolerance range for the position of the connection point in the region of the heat transfer surface

[0064] 32Minimum gap height

[0065] 34 Maximum gap height

[0066] 36 Dispensing volume for smallest gaps

[0067] 38 Dispensing volume for maximum gap height

[0068] 40 cooling channels

[0069] 42 Acceptance structure

[0070] 44 Reception area

[0071] 46 recess

[0072] 48 gap

Claims

1. A method for producing a thermal interface in a battery (10) for a motor vehicle, comprising the following steps: - providing at least one battery module (12) and at least one receiving structure (42) having a receiving area (44), the receiving area (44) having a heat transfer surface (14) and being used to receive the battery module side of the battery module (12) in a prescribed installation position, wherein the receiving structure (42) comprises a cooling plate having a plurality of cooling channels (40) arranged therein; - applying a heat conducting material (18) to the heat transfer surface (14) in a predetermined dosage amount, the heat conducting material (18) being used to fill a gap (48) between the heat transfer surface (14) and the battery module side in a prescribed installation position; - installing the battery module (12) while filling with the applied heat-conducting material (18), whereupon the filled heat-conducting material (18) fills the gap (48) and forms a thermal interface between the battery module side and the heat transfer surface (14); - wherein before applying the heat-conducting material (18), at least one recess (46) is produced in the receiving area (44) with a volume coordinated with a predetermined dosage amount of the heat-conducting material (18), the recess being used as a container for excess heat-conducting material (18) when filling with the heat-conducting material (18), and the recess (46) is formed between corresponding cooling channels (40) in the plurality of cooling channels (40), and the recess (46) is constructed to be vented to the outside during filling with the heat-conducting material (18) to prevent air locks from being contained inside the heat-conducting material (18).

2. The method according to claim 1, It is characterized in that The metered amount is predetermined in such a way that, after filling with the heat conducting material (18), the gap (48) is completely filled with the heat conducting material while maximally utilizing a tolerance range associated with a gap volume of the gap (48).

3. The method according to claim 1 or 2, It is characterized in that The arrangement of the recesses (46) is predetermined in coordination with a predetermined application pattern of the heat conducting material (18).

4. The method according to claim 3, It is characterized in that The coating pattern provides a plurality of lines of the thermally conductive material (18) running side by side, wherein a plurality of the recesses (46) are produced as grooves running parallel to the provided lines.

5. The method according to claim 3, It is characterized in that The coating pattern provides a plurality of points of the thermally conductive material (18) arranged next to one another, wherein a plurality of recesses in the recesses (46) between the provided points are produced as depressions.

6. The method according to claim 1, It is characterized in that At least one recess (46) in the receiving area (44) is produced by means of an extrusion method.

7. The method according to claim 1, It is characterized in that The at least one recess (46) is produced by means of a punching process.

8. The method according to claim 1, It is characterized in that The at least one recess (46) has a depth greater than its width and / or a depth greater than its length.

9. A battery (10) for a motor vehicle, comprising: - at least one battery module (12); at least one receiving structure (42) having a receiving area (44) with a heat transfer surface (14), in which the battery module (12) is received on its battery module side in a prescribed installation position, wherein the receiving structure (42) comprises a cooling plate having a plurality of cooling channels (40) arranged therein; a heat-conducting material (18) which fills a gap (48) between the heat transfer surface (14) and the battery module side and forms a thermal interface between the battery module side and the heat transfer surface (14); - wherein the receiving area (44) has at least one recess (46) serving as a container for excess heat-conducting material (18), and wherein the recess (46) is formed between corresponding cooling channels (40) among the plurality of cooling channels (40), and wherein the recess (46) is configured to be vented to the outside during packing of the heat-conducting material (18) to prevent a gas lock from being contained inside the heat-conducting material (18).

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