Battery for a motor vehicle

Abstract

Battery (1) comprising a battery module (2) and a temperature control plate (4), wherein a thermal paste (3) is arranged between the battery module (2) and the temperature control plate (4), where An electrically insulating spacer (5) is arranged between the battery module (2) and the temperature control plate (4), characterized by the fact that the electrically insulating spacer (5) has a thickness which, when a battery module (2) is arranged on the temperature control plate (4), leads to an elastic and / or plastic deformation of the temperature control plate (4), at least in the area where the electrically insulating spacer (5) is in contact with the temperature control plate (4).

Description

Technical field

[0001] The present invention relates to a battery, in particular a traction battery for a motor vehicle, according to the preamble of claim 1. State of the art

[0002] The performance requirements for modern batteries are constantly increasing, with development focusing on optimizing the use of available space and materials to improve the power-to-weight ratio. Safety is always a priority in this development process, for example, to prevent short circuits.

[0003] Batteries can have a battery casing in which one or more battery modules are installed. Within the battery modules, the actual battery cells are organized mechanically, logically, and electrically. A temperature control plate for maintaining the temperature of the battery modules may be provided, with the temperature control plate typically being cooled or heated by a temperature control medium.

[0004] The battery modules can be thermally connected to the temperature control plate by means of a thermal interface material. A thermal paste can be used as the thermal interface material between the battery module and the temperature control plate.

[0005] It is known from DE 10 2021 000 981 A1 to insert a structural mat between the battery cell and the housing base in order to facilitate disassembly, in particular the removal of battery cells.

[0006] A battery with a composite structure is known from DE 10 2012 221 689 A1.

[0007] A battery storage system is known from DE 10 2018 102 957 A1.

[0008] A battery module is known from DE 10 2014 016 471 B3. Description of the invention

[0009] Starting from the known state of the art, it is an object of the present invention to provide a further improved battery.

[0010] The problem is solved by a battery, preferably a traction battery for a motor vehicle, having the features of claim 1. Advantageous embodiments are described in the dependent claims, the description, and the figures.

[0011] Accordingly, a battery, in particular a traction battery for a motor vehicle, is proposed, comprising a battery module and a temperature control plate, wherein a thermally conductive paste is arranged between the battery module and the temperature control plate. According to the invention, an electrically insulating spacer is arranged between the battery module and the temperature control plate.

[0012] By using a spacer, a minimum distance in the form of a gap between the battery module and the temperature control plate can be ensured, so that the electrical insulation between the battery module and the temperature control plate can be maintained despite unevenness in the temperature control plate or particles in the gap, such as metal shavings.

[0013] To prevent the spacer from forming an electrically conductive bridge between the battery module and the temperature control plate, it is made of an electrically insulating material, preferably a plastic.

[0014] Accordingly, the electrically insulating spacer can have a thickness that ensures a predetermined gap between the battery module and the temperature control plate.

[0015] This arrangement of the spacer also makes it possible to ensure a minimal gap without an additional safety margin between the battery module and the temperature control plate, thus enabling a compact design and advantageous and effective temperature control of the battery module.

[0016] Furthermore, this method allows for a reduction in the volume of thermal paste required compared to conventional applications, as only the actual gap thickness needs to be filled with thermal paste, rather than a gap increased by safety margins. By reliably setting a predefined minimum gap, the amount of thermal paste can be reduced and kept to a minimum, thus saving costs and weight. Additionally, the reduced use of thermal paste also has a positive effect on the battery's lifespan.

[0017] According to the invention, in the assembled state, the electrically insulating spacer, due to its thickness, causes the temperature control plate to be elastically and / or plastically deformed. The electrically insulating spacer, at least in the area where the spacer contacts the temperature control plate, effectively pushes the plate away when the battery module presses against it during assembly.

[0018] The chosen material of the tempering plate, for example the alloy of the tempering plate material, ensures that the forces acting on the battery module due to deformation remain within the permissible range.

[0019] The electrically insulating spacer can have a thermal conductivity that matches that of the thermal paste. This allows for a particularly homogeneous thermal conductivity.

[0020] Heat transfer is achieved that extends across the entire surface of the temperature control plate.

[0021] The underside of the spacer, which rests on the top side of the temperature control plate, can be shaped to ensure full-surface contact between the underside of the spacer and the top side of the temperature control plate. Similarly, the top side of the spacer can contact the underside of the battery module, with the contact also being full-surface.

[0022] The desired minimum gap is set by the contact between the battery module and the spacer. At the same time, this provides additional support for the battery module against the temperature control plate, which can have a beneficial effect on the overall stability of the battery.

[0023] The electrically insulating spacer can be bonded to the temperature control plate. This ensures reliable positioning of the spacer and thus simplifies battery installation.

[0024] In another configuration, the thickness of the electrically insulating spacer can also result in a gap remaining between the spacer and the temperature control plate and / or the battery module, and this gap may then be at least partially filled with thermal paste. This situation can also occur, for example, if the displacement resistance of the thermal paste causes the gap between the battery module and the temperature control plate to remain larger than the thickness of the electrically insulating spacer.

[0025] The electrically insulating spacer can be arranged on a central plane of the battery module. For example, the spacer is positioned centrally on the upper surface of the temperature control plate facing the battery module, and the battery module is positioned such that the spacer is centered on its underside. Thus, in a sectional view, the spacer, the temperature control plate, and the battery module share a common central plane.

[0026] In an advantageous embodiment, the spacer has a length that is less than or equal to the length of the battery module extending in a parallel direction.

[0027] This allows for contact between the battery module and the spacer over the largest possible direction, thus ensuring a constant gap. To still enable a compact battery design and provide advantageous temperature control, the length of the spacer is less than or equal to the length of the battery module.

[0028] The electrically insulating spacer can be arranged at a position on the temperature control plate that lies within an area of ​​the temperature control plate formed by fastening devices for mounting the battery module, for example in a central area of ​​this area.

[0029] This allows the spacer to be positioned in the area of ​​greatest sagging between the mounting points, thus providing additional support for the battery module. Simultaneously, the spacer also ensures the correct gap dimensioning in this area of ​​greatest sagging.

[0030] The thermal paste can at least surround the spacer laterally.

[0031] Surrounding the spacer with thermal paste leads to advantageous temperature control of the battery module even in the area of ​​the spacer, so that a substantially homogeneous temperature control can be achieved here.

[0032] The electrically insulating spacer can have a constant cross-section along its length, and the cross-section can be square or rectangular.

[0033] This results in simple and cost-effective manufacturing of the spacer. Furthermore, the constant cross-section ensures a uniform load distribution along the length of the spacer. To optimally shape the contact surfaces between the spacer and the battery module and temperature control plate, the respective contact surface of the spacer is shaped parallel to the contact surface of the component in contact (temperature control plate or battery module).

[0034] The height of the spacer can be less than its length or width. This design is cost-effective and reduces weight. Furthermore, the contact area is relatively large, ensuring a consistent gap and improved load distribution.

[0035] The spacer can be molded in one piece.

[0036] The one-piece design of the spacer is cost-effective to manufacture and offers structural advantages regarding its placement between the temperature control plate and the battery module. Furthermore, a one-piece design results in a more uniform force distribution across the surface, thus positively influencing the uniform deformation of the temperature control plate.

[0037] The temperature control plate can have a recess which forms a receptacle for the electrically insulating spacer; the electrically insulating spacer can then be arranged in the recess and the electrically insulating spacer can project beyond the plane formed by the temperature control plate.

[0038] To form the recess in the temperature control plate, the plate is permanently deformed, preferably by deep drawing. After deformation, the recess can have a bearing surface that can accommodate the underside of the spacer. This ensures advantageous support of the spacer in the recess, allowing for a constant gap. Furthermore, the structural load on the temperature control plate in the installed state is advantageous.

[0039] The spacer is shaped in such a way that, when positioned in the recess, it protrudes from the recess and thus from the plane formed by the temperature control plate, thereby ensuring the desired gap between the battery module and the temperature control plate.

[0040] At least two electrically insulating spacers can be provided per battery module.

[0041] This allows for improved load distribution and ensures a consistent gap. The arrangement and shape of the additional spacers are arbitrary, provided that they possess at least electrically insulating properties to prevent short circuits and are shaped to ensure a uniform gap.

[0042] The other spacers can, for example, run parallel and / or orthogonally to each other.

[0043] This ensures advantageous load distribution and maintains the gap on the underside of the battery module. If the additional spacers are arranged in such a way that they overlap with each other or with the spacer itself, they must be shaped so that their upper surfaces and the spacer's surface are flush. This can be achieved, for example, by dividing the additional spacers to allow contact on the opposing sides of the additional spacers or the spacer, although the application is not limited to the arrangement possibilities mentioned here.

[0044] The temperature control plate can include a base plate and cooling channels, thus essentially forming a conventional temperature control plate. Brief description of the characters

[0045] Preferred further embodiments of the invention are explained in more detail by the following description of the figures. These show: Fig. 1 a schematic sectional view through a battery, and Fig. 2 a perspective view of a tempering plate. Detailed description of preferred embodiments

[0046] Preferred embodiments are described below with reference to the figures. Identical, similar, or equivalent elements in the different figures are designated with identical reference numerals, and repeated descriptions of these elements are sometimes omitted to avoid redundancy.

[0047] In Fig. Figure 1 shows a schematic sectional view through a section of a battery 1, comprising a battery module 2 and a temperature control plate 4. The battery 1 has a housing, which is only indicated here, and includes, for example, a cover 23, the temperature control plate 4 forming the base of the housing, and lateral mounting structures 24 for securing the battery module 2 in the housing.

[0048] A thermal paste 3 is arranged between the battery module 2 and the temperature control plate 4 in order to establish a thermal connection between the temperature control plate 4 and the battery module 2 and thus enable efficient temperature control of the battery cells contained in the battery module 2.

[0049] The battery module 2 is mounted to the lateral mounting structures 24 of the housing by means of a mounting device 21. For this purpose, the mounting device 21 includes, for example, a screw bolt 22 by means of which the battery module 2 is screwed to the lateral mounting structures 24 of the housing and fixed in a predetermined position. The mounting device 21 also ensures that the battery module 2 is positioned relative to the temperature control plate 4 in a predetermined manner. The mounting device 21 can, for example, also be in the form of a snap-fit ​​or another screwless fastening mechanism.

[0050] The thermal paste 3, located between the battery module 2 and the temperature control plate 4, is distributed and partially displaced during the process of attaching the battery module 2 to the lateral mounting structure 24 of the housing, resulting in essentially complete wetting with the thermal paste 3 and, consequently, an essentially full-surface thermal connection between the battery module 2 and the temperature control plate 4. The thermal paste 3 also provides electrical insulation.

[0051] To prevent direct contact between the battery module 2 and the temperature control plate 4, which could lead to electrical contact and, in extreme cases, a short circuit, an electrically insulating spacer 5 is provided, positioned between the temperature control plate 4 and the battery module 2. For example, the spacer 5 prevents insufficient electrical insulation between the battery module 2 and the temperature control plate 4 due to vibrations during operation or flow of the thermal paste 3 at a later time, which could result from an insufficient thickness of the thermal paste 3 applied between them.

[0052] The thickness of the spacer 5 can be adjusted to ensure that a minimum distance between the battery module 2 and the temperature control plate is maintained at all times. This minimum distance is preferably also greater than the maximum size of dirt particles, such as metal shavings, that might be present during battery assembly. This ensures that even if contaminants are unintentionally introduced during the assembly process, the electrical insulation between the battery module 2 and the temperature control plate 4 remains intact.

[0053] In its assembled state, the thickness of the electrically insulating spacer 5 can cause the temperature control plate 4 to deform elastically and / or plastically. For example, the electrically insulating spacer 5 can, at least in the area where the spacer 5 contacts the temperature control plate 4, essentially push the plate away if the battery module 2 presses against the electrically insulating spacer 5 during assembly.

[0054] The selected material of the temperature control plate 4, for example the alloy of the material of the temperature control plate 4, can ensure that the forces acting on the battery module 2 due to deformation remain within the permissible range.

[0055] In another arrangement, the thickness of the electrically insulating spacer 5 can also result in a gap remaining between the electrically insulating spacer 5 and the temperature control plate 4 and / or the battery module 2, and this gap may then be at least partially filled with thermal paste 3. This situation can also occur, for example, if the displacement resistance of the thermal paste 3 causes the gap between the battery module 2 and the temperature control plate 4 to remain larger than the thickness of the electrically insulating spacer 5.

[0056] The spacer 5 can be arranged in a position determined by the geometric arrangement of the battery module 2, the temperature control plate 4 and the fastening devices 21 relative to each other.

[0057] For example, the spacer 5, as shown in the embodiment illustrated here, can be arranged centrally between the fixed mounting points defined by the fastening devices 21. At this position, or in this area, the sag is virtually at its maximum, and the potential for deformation of the battery module 2 and / or the temperature control plate 4 due to vibrations is potentially greatest. Therefore, the spacer 5 can achieve its best effect in this area.

[0058] The spacer 5 can also be arranged in other positions on the temperature control plate 4, for example between the vibration nodes of the temperature control plate 4, if it is excited to vibrate under operating conditions.

[0059] The spacer 5 can be designed with a thickness such that it is clamped between the battery module 2 and the temperature control plate 4 when the battery module 2 is fixed to the lateral mounting structure 24 via the mounting device 21. In other words, in the assembled state, a slight deformation of the temperature control plate 4 and / or the battery module 2 and / or the spacer 5 can occur, resulting in a slight preload.

[0060] In the illustrated embodiment, the spacer 5 is rectangular and molded in one piece from a plastic material. The spacer 5 makes full contact with a bottom surface 20 of the battery module 2 on a top surface 50 and with a top surface 40 of the temperature control plate 4 in the area of ​​deformation 41 on a bottom surface 51. This ensures an advantageous load distribution across the contacting surfaces.

[0061] The spacer 5 and the battery module 2 are arranged on the temperature control plate 4, for example, such that the spacer 5 is located on a median plane 6 with respect to the battery module 2. For this purpose, the spacer 5 is located centrally on the top surface 40 of the temperature control plate 4, and the battery module 2 is located such that the spacer 5 is located centrally on the battery module.

[0062] Furthermore, the spacer 5 has a length that is shorter than the parallel length of the battery module 2. The in Fig. The direction of extension L shown in Figure 1 is an axis that runs parallel to the length of the battery module 2 and the length of the spacer 5. The spacer 5 can also have the same length as the battery module 2.

[0063] The spacer 5 is arranged at a position on the temperature control plate 4 that lies within an area of ​​the temperature control plate 4 formed by the fastening devices 21 for attaching the battery module 2. The spacer can be located in a central or inner region of this area. In other words, the area is bounded by the fastening devices 21, such that the spacer 5 lies within the boundary formed by the fastening devices 21.

[0064] To ensure optimal temperature control of the battery module 2, thermal paste 3 is applied over the entire surface of the gap formed by the spacer 5 between the battery module 2 and the temperature control plate 4. The thermal paste 3 makes full contact with the spacer 5 on all sides, thus enabling optimal temperature control even in the area of ​​the spacer 5.

[0065] If the spacer 5 has the same or a similar heat transfer coefficient as the thermal paste 3, a particularly homogeneous heat transfer can take place here.

[0066] For this purpose, the thermal paste 3 can be applied to the temperature control plate 4 after the spacer 5 has been arranged, and then the battery module 2 can be mounted.

[0067] The temperature control plate 4 comprises a base plate 44 and cooling channels 45. A temperature control medium (not shown) can be passed through the cooling channels 45 so that, depending on the operating state of the battery 1, heat is removed from or supplied to the battery module 2.

[0068] In Fig. Figure 2 shows a perspective view of a temperature control plate 4. The temperature control plate 4 has a plurality of recesses 42 in which spacers 5 are arranged.

[0069] The temperature control plate 4 is deformed by deep drawing to create the recesses 42, so that the temperature control plate 4 has a defined contact surface for spacers 5. After a spacer 5 is placed in the recess 42, the spacer 5 protrudes from the recess 42 to achieve the required spacing between the battery module 2 and the temperature control plate 4. This creates a contact surface for the battery module 2, ensuring a minimum gap between the battery module 2 and the temperature control plate 4.

[0070] Where applicable, all individual features shown in the exemplary embodiments can be combined and / or exchanged without leaving the scope of the invention. Reference symbol list 1 battery 2 battery modules 3 Thermal paste 4. Tempering plate 5 spacers 6 Middle level 20 Underside of the battery module 21 Fastening device 22 screw bolts 23 lids 24 lateral mounting structures 40 Top of the tempering plate 41 Deformation 42 depression 43 Cooling unit 44 Base plate 45 Cooling channel 50 Top of the spacer 51 Underside of the spacer L Direction of extension

Claims

[1] Battery (1) comprising a battery module (2) and a temperature control plate (4), wherein a thermal paste (3) is arranged between the battery module (2) and the temperature control plate (4), where an electrically insulating spacer (5) is arranged between the battery module (2) and the temperature control plate (4), characterized by , that the electrically insulating spacer (5) has a thickness which, when a battery module (2) is arranged on the temperature control plate (4), leads to an elastic and / or plastic deformation of the temperature control plate (4) at least in the region where the electrically insulating spacer (5) rests on the temperature control plate (4). [2] Battery (1) according to claim 1, characterized by that the electrically insulating spacer (5) has a thermal conductivity which corresponds to the thermal conductivity of the thermal paste (3). [3] Battery (1) according to claim 1 or 2, characterized bythat the electrically insulating spacer (5) has a thickness that ensures a predetermined gap between the battery module (2) and the temperature control plate (4). [4] Battery (1) according to one of the preceding claims, characterized by that the electrically insulating spacer (5) is glued to the temperature control plate (4). [5] Battery (1) according to one of the preceding claims, characterized by that the electrically insulating spacer (5) is arranged on a central plane (6) of the battery module (2). [6] Battery (1) according to one of the preceding claims, characterized by that the electrically insulating spacer (5) is arranged at a position of the temperature control plate (4) which lies within a surface of the temperature control plate (4) formed by fastening devices (21) for fastening the battery module (2) or in a central region of this surface. [7] Battery (1) according to one of the preceding claims, characterized by that the electrically insulating spacer (5) has a length which is less than or equal to a length of the battery module (2) extending parallel thereto. [8] Battery (1) according to one of the preceding claims, characterized by that the thermal paste (3) surrounds the electrically insulating spacer (5) at least laterally. [9] Battery (1) according to one of the preceding claims, characterized by that the electrically insulating spacer (5) has a constant cross-section over its length, wherein the cross-section is square or rectangular. [10] Battery (1) according to one of the preceding claims, characterized bythat the temperature control plate (4) has a recess (42) which forms a receptacle for the electrically insulating spacer (5), the electrically insulating spacer (5) is arranged in the recess (42) and the electrically insulating spacer (5) projects beyond the plane formed by the temperature control plate (4). [11] Battery (1) according to one of the preceding claims, characterized by that at least two electrically insulating spacers (5) are provided per battery module (2).

Images