Method for creating a thermal interface between a contact surface and a receiving surface

Abstract

A method for creating a thermal interface between a contact surface and a receiving surface, comprising: providing at least one contact surface S1; providing a receiving surface S2, wherein the receiving surface comprises an area in which the contact surface can be thermally connected with the receiving surface. The method further comprises: applying a thermally conductive paste S3 in the area of the receiving surface; placing the contact surface onto the receiving surface, creating vibrations S4 on the contact surface and / or the receiving surface, wherein by creating the vibrations a uniform force distribution is provided during the placement of the contact surface onto the receiving surface.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for creating a thermal interface between a contact surface and a receiving surface. BACKGROUND

[0002] In an electrically driven vehicle, the vehicle is driven by an electric motor. The energy required for the electric motor is provided by a traction battery. The traction battery comprises a plurality of battery modules which are accommodated in a housing of the traction battery. The battery modules heat up during operation, which can lead to damage to the traction battery, which is why the battery modules have to be cooled. For this purpose, a thermally conductive paste is applied to a receiving surface of the housing of the battery module before the battery module is accommodated in the housing. By means of the thermally conductive paste, excess heat is dissipated during operation of the battery module. The battery module is then accommodated in the receiving surface of the housing, wherein a high setting force is generated when the battery module is accommodated. Due to the high setting force, it is possible that the battery module is damaged. Furthermore, it is possible that, when the battery module is accommodated, the thermally conductive paste is distributed unevenly on the receiving surface, which leads to an uneven dissipation of heat from the battery module.

[0003] DE 10 2018 118 682 relates to a battery for a motor vehicle, comprising a battery housing having at least one battery module arranged in a module receiving region of the battery housing, a housing seal sealing the module receiving region, and a cooling plate arranged on the battery module, which can be flowed through by a coolant. Furthermore, the battery comprises at least one connection piece connected to the cooling plate, which serves to at least indirectly connect to a coolant connection of the motor vehicle for the supply and discharge of coolant, and a coolant seal arranged on the connection piece, which is arranged outside the module receiving region of the battery housing. SUMMARY

[0004] It is therefore an object of the present invention to achieve the accommodation of a battery module in a battery housing using a mechanism which is as simple in construction as possible, without the battery module being damaged in the process.

[0005] This object is achieved by the subject matter of the present invention. Advantageous refinements of the invention are given in the description and the drawings.

[0006] One aspect of the present invention relates to a method for creating a thermal interface between a contact surface and a receiving surface, comprising:

[0007] At least one contact surface is provided. A receiving surface is then provided, wherein the receiving surface comprises a region in which the contact surface can be thermally connected to the receiving surface. A thermally conductive paste is then applied in the region of the receiving surface, the contact surface is arranged on the receiving surface, and vibrations are generated on the contact surface and / or the receiving surface, wherein, by generating the vibrations, a uniform force distribution is provided during the arrangement of the contact surface on the receiving surface.

[0008] The contact surface can be, for example, a surface of a battery module housing. The battery module housing can comprise one or more battery cells. The battery cells can be, for example, pouch cells or prismatic battery cells. In another embodiment, the battery module housing does not comprise any battery cells.

[0009] The receiving surface can be, for example, a surface of a battery housing. In the region where the contact surface can be thermally connected to the receiving surface, a thermally conductive paste is applied to the receiving surface. The thermally conductive paste can be applied to the receiving surface in the form of a strip, as a plane or in a skeletal shape.

[0010] In the case of strip-shaped application, the thermally conductive paste is applied to the receiving surface in predetermined regions. Between the predetermined regions, a spacing is selected at which no thermally conductive paste is applied.

[0011] In the case of planar application, the thermally conductive paste is applied over a large area on the receiving surface.

[0012] The placement of the contact surface onto the receiving surface can be, for example, the pressing of the contact surface against the receiving surface. By placing the contact surface onto the receiving surface, a strong force acts on the components comprising the contact surface and / or the receiving surface. In order to avoid damaging the components, vibrations are generated on the contact surface and / or the receiving surface. By means of the vibrations, a uniform force distribution is provided during the placement of the contact surface onto the receiving surface. The constantly increasing force acting on the contact surface and / or the receiving surface during the placement is temporarily interrupted by the continuous vibrations and is distributed uniformly over the contact surface and / or the receiving surface.

[0013] The vibrations can be generated by means of an oscillating mass. Here, the vibration frequency or the bandwidth of the vibration spectrum depends on the shape and size of the battery module, the contact surface and / or the receiving surface, and on the material properties of the thermally conductive paste and the size of the insertion force when the battery module is inserted. The frequency of the vibrations generated on the contact surface can be different from the frequency of another vibration generated on the receiving surface.

[0014] In one embodiment, the vibrations can be input at specific locations on the components. For example, screw tabs can be provided on the components. The vibrating mass can be docked on the screw tabs by means of a device and generate vibrations which are transmitted to the components via the screw tabs.

[0015] In one embodiment, vibrations are introduced over the entire surface of the contact surface and / or over the entire surface of the receiving surface.

[0016] By generating vibrations on the contact surface and / or the receiving surface during the placement of the contact surface onto the receiving surface, a uniform force distribution on the contact surface and / or the receiving surface can be achieved. Furthermore, a smaller amount of the thermally conductive paste can be applied to the receiving surface, since the forces acting on the contact surface and / or the receiving surface during the placement are interrupted by the vibrations. Due to the uniform force distribution ensured by the vibrations, the thermally conductive paste is distributed uniformly in the contact surface area. Due to the uniform distribution of the thermally conductive paste, a uniform thermal connection between the contact surface and the receiving surface can also be achieved.

[0017] Furthermore, by generating vibrations, heat is generated. By the additional heat, the thermally conductive paste can be cured more quickly, whereby the overall production time from the placement of the contact surface to the curing of the thermally conductive paste can be reduced.

[0018] In one embodiment, the contact surface is a surface of a battery module housing, wherein the battery module housing is designed to accommodate at least one battery cell, and the receiving surface is arranged in the battery. The receiving surface can be a surface of the battery housing. The battery can comprise a cooling plate connected to the receiving surface. Another vibration can be generated on the cooling plate. For example, vibrations can be generated on the battery module housing, but also on the battery housing and the cooling plate.

[0019] In one embodiment, the vibrations are applied to a workpiece carrier. The battery module housing can be loaded into the battery housing by means of the workpiece carrier, so that the surface of the battery module housing is placed onto the surface of the battery housing. The vibrations are then transmitted from the workpiece carrier to the battery module housing. By introducing the vibrations directly into the workpiece carrier, no further mechanical fastening is required on the battery module housing. Furthermore, the workpiece carrier can be a fixed component of the production process. The production time can thus be shortened, since no additional mechanical fastening of the vibration mass to the battery module housing is necessary, so that time can be saved. For example, the battery housing can be arranged on a further workpiece carrier. The vibrations can also be input into the further workpiece carrier.

[0020] In one embodiment, the vibrations are generated on a battery housing of a battery.

[0021] In one embodiment, the contact surface is a surface of a battery cell. The battery cell can be, for example, a pouch cell or a prismatic cell. For example, the contact surface can be an end face of a pouch cell. A plurality of battery cells can be placed on the receiving surface and thermally connected to the area of the receiving surface. A battery cell frame can hold the individual battery cells together.

[0022] In one embodiment, the vibrations are generated on a vehicle body accommodation, wherein the battery is accommodated in the vehicle body accommodation.

[0023] In one embodiment, the contact surface is a surface of a busbar, and the receiving surface is arranged in a vehicle body accommodation of a vehicle.

[0024] In one embodiment, vibrations are generated on the contact surface and / or the receiving surface at predetermined positions of the contact surface and / or the receiving surface.

[0025] For example, marker points can be provided on the contact surface and / or the receiving surface. The marker points can then be detected by optical sensors. The optical sensors can be arranged on an automated device. The automated device can for example be a robot. With the aid of the marker points, the vibration mass can be positioned on the contact surface and / or the receiving surface at precise and predetermined positions.

[0026] In one embodiment, by generating vibrations on the contact surface and / or the receiving surface, the contact surface and / or the receiving surface are caused to move, and the direction of movement of the contact surface is opposite to the direction of movement of the receiving surface. Vibrations can be generated on the contact surface and / or the receiving surface such that the contact surface and / or the receiving surface vibrate in different directions. For example, the contact surface can vibrate along the receiving surface in a diagonal direction, while the receiving surface vibrates along the contact surface in a horizontal direction.

[0027] In one embodiment, the frequency of the vibrations is set, wherein the frequency is set in dependence on the number of predetermined positions and / or the size of the respective predetermined positions. The predetermined positions can be positions on the battery module housing or the battery housing. The predetermined positions can be positions on the cooling plate. The size of the predetermined positions can vary. For example, vibrations can be input onto the entire surface of the battery housing, while another vibration is input onto the battery module housing only on a small area, for example a corner or an edge of the battery module housing. For example, vibrations can be input onto the contact surface and / or the receiving surface only at certain points.

[0028] In one embodiment, the frequency is adjustable during the placement of the contact surface onto the receiving surface.

[0029] By means of at least one sensor arranged on the contact surface, a force acting onto the contact surface during the placement can be detected. If this force changes, the frequency of the vibrations can be adjusted in dependence on the force. The data processing device can be connected to the sensor by means of a wireless interface. The data processing device evaluates the data detected by the sensor and transmits a signal to the robot or the eccentric wheel, which then adjusts the frequency of the vibrations.

[0030] In one embodiment, the at least one sensor detects a force curve during the placement of the contact surface onto the receiving surface.

[0031] In one embodiment, a continuously increasing or decreasing frequency range can be set. Thus, during the placement of the contact surface onto the receiving surface, the frequency can be adapted to the force curve. As a result, the frequency can be precisely adapted to the currently acting force during the entire process of placing the contact surface onto the receiving surface.

[0032] In one embodiment, the frequency of the vibration depends on the surface condition of the contact surface and / or the receiving surface. In the case of a rough surface of the contact surface and / or the receiving surface, the thermally conductive paste adheres firmly to the contact surface and / or the receiving surface, whereby a higher vibration frequency is required in order to achieve a good distribution of the thermally conductive paste.

[0033] In the case of a smooth surface, the thermally conductive paste is distributed quickly, whereby a lower frequency is sufficient here.

[0034] In one embodiment, the frequency of the vibration depends on the amount of thermally conductive paste applied. The more thermally conductive paste is applied to the area of the receiving surface, the greater the force that has to be used when placing the contact surface on the receiving surface. The greater the force used, the higher the frequency of the vibration has to be. By means of the vibration and the resulting uniform force distribution on the contact surface and / or the receiving surface, the thermally conductive paste is uniformly distributed in the thermally connectable area of the receiving surface.

[0035] The density and viscosity of the thermally conductive paste also influence the frequency of the vibration. If the thermally conductive paste, for example, has a very thick consistency, the vibration frequency should be adjusted accordingly so that the thermally conductive paste can be distributed well.

[0036] In one embodiment, the vibration is generated by means of an eccentric. For example, a gripping surface can be provided on the contact surface and / or the receiving surface. On the gripping surface, for example, an eccentric can be arranged, without the need for additional mechanical connecting parts here. BRIEF DESCRIPTION OF DRAWINGS

[0037] An advantageous embodiment of the application is explained below with reference to the drawings.

[0038] Figure 1 is a schematic representation of a method for producing a thermal interface between a contact surface and a receiving surface.

[0039] The figure is merely a schematic representation and serves merely to explain the application. Identical or identically acting parts are uniformly designated by the same reference numerals. DETAILED DESCRIPTION

[0040] Figure 1 A schematic representation of a method for producing a thermal interface between a contact surface and a receiving surface is shown. In this embodiment according to the figure, the contact surface is a surface of a battery module housing and the receiving surface is a surface of a battery housing.

[0041] In a first step, a surface of a battery module housing is provided (S1). The battery module housing comprises battery cells, for example pouch cells. In another embodiment, the battery module housing comprises prismatic battery cells. In another embodiment, the battery module housing does not comprise any battery cells.

[0042] In a second step, a surface of the battery housing is provided (S2). The surface of the battery housing comprises an area in which the surface of the battery module housing can be thermally connected with the surface of the battery housing.

[0043] In a third step, a thermally conductive paste is applied to the surface area of the battery housing (S3). The thermally conductive paste can be applied, for example, by strip application, plane application or skeleton application. The thermally conductive paste ensures a good thermal connection between the battery housing and the battery module housing, so that the excess heat of the battery cells can be well dissipated.

[0044] In a fourth step, the surface of the battery module housing is placed onto the surface of the battery housing and a vibration is generated on the surface of the battery module housing and / or on the surface of the battery housing (S4). The placement is carried out by pressing the surface of the battery module housing against the surface of the battery housing. By the pressing, the thermally conductive paste is also distributed on the surface of the battery housing. The battery housing can then be tightened with a lid. The lid protects the battery module enclosed in the battery housing from external influences such as dust or damage.

[0045] List of reference signs

[0046] S1 providing a surface of a battery module housing

[0047] S2 providing a surface of a battery housing

[0048] S3 applying a thermally conductive paste to the surface of the battery housing

[0049] S4 placing a surface of a battery module housing onto a surface of a battery housing and generating a vibration

Claims

1. A method for generating a thermal interface between a contact surface and a receiving surface for a battery, comprising: providing at least one contact surface (SI); providing a receiving surface (S2), wherein the receiving surface comprises a region in which the contact surface can be thermally connected to the receiving surface; applying a thermally conductive paste in the region of the receiving surface (S3); and positioning the contact surface onto the receiving surface, generating a vibration on the contact surface and / or the receiving surface (S4), wherein by generating the vibration a uniform force distribution is provided during positioning the contact surface onto the receiving surface, wherein a frequency of the vibration generated on the contact surface is different from a frequency of another vibration generated on the receiving surface.

2. The method of claim 1, wherein, The contact surface is a surface of a battery module housing, wherein the battery module housing is designed to accommodate at least one battery cell, and the receiving surface is arranged in the battery and is a surface of a battery housing of the battery.

3. The method of claim 2, wherein, The vibration is generated on the battery housing of the battery.

4. The method according to claim 1 or 2, characterized in that, The vibration is generated on a vehicle body accommodation, wherein the battery is accommodated in the vehicle body accommodation.

5. The method of claim 1, wherein, The contact surface is a surface of a busbar and the receiving surface is arranged in a vehicle body accommodation of a vehicle.

6. The method according to any one of claims 1 to 3, characterized in that, The vibration is generated on the contact surface and / or the receiving surface at predetermined positions of the contact surface and / or the receiving surface.

7. The method according to any one of claims 1 to 3, characterized in that, By generating the vibration on the contact surface and / or the receiving surface, the contact surface and / or the receiving surface is moved and the direction of movement of the contact surface is opposite to the direction of movement of the receiving surface.

8. The method according to any one of claims 1 to 3, characterized in that, The frequency of the vibration is set, wherein the frequency is set depending on the number of predetermined positions and / or the size of the respective predetermined position.

9. The method according to any one of claims 1 to 3, characterized in that, The frequency of the vibration depends on the amount of the applied thermally conductive paste.

10. The method according to any one of claims 1 to 3, characterized in that, The vibration is generated by an eccentric.

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