Battery module

Abstract

The invention relates to a battery module having a plurality of battery cells (2) and having an electrical switching device (3), a first connection (31) of the electrical switching device (3) being electrically conductively connected to a battery cell (21) of the plurality of battery cells (2) via a first busbar (51), the second connection (32) of the electrical switching device (3) is electrically conductively connected to the total partial pressure tap (4) of the battery module (1) via a second busbar (52), and the at least one heat pipe (6) is connected to the electrical switching device (3) and the temperature control body (8) in a heat-conducting manner.

Description

Technical Field

[0001] The invention relates to a battery module of the type specified in the independent claim. Background Art

[0002] A battery module generally has a plurality of independent battery cells, each of which has a positive voltage divider tap and a negative voltage divider tap, wherein the corresponding voltage divider taps can be electrically connected to each other for electrically conductive series and / or parallel connection of the plurality of battery cells, and thus can be connected to each other to form a battery module. In particular, the battery cells can each have a first voltage divider tap (especially a positive voltage divider tap) and a second voltage divider tap (especially a negative voltage divider tap), and the first voltage divider tap and the second voltage divider tap are electrically conductively connected to each other via a cell connector, thereby forming an electrical series and / or parallel connection. In addition, the battery modules can also be connected to each other to form a battery or an entire battery system.

[0003] Electrical switching devices (eg relays) are usually arranged between voltage tappings of battery cells arranged at the ends of a battery module and a total voltage tapping of the battery module and are used in principle to switch (ie connect and disconnect) a battery module or a battery comprising such a battery module.

[0004] In principle, such electrical switching devices must be actively cooled, in particular because they conduct the entire current of the battery module. For this purpose, the electrical switching device can be connected to a heat sink, such as a housing made of metal of the battery module.

[0005] Prior art in this respect includes, for example, DE 102022203908, DE 102022203860 and DE 102022203861, which describe cooling of electrical switching devices by liquid cooling or air cooling, wherein cooling fins are an integral component of the housing structure of the housing of the battery module.

[0006] In order to achieve good heat dissipation of the electrical switching device, the housing of the battery module is preferably produced from a metal with relatively good thermal conductivity, preferably as an aluminum die-cast component. Summary of the invention

[0007] A battery module having the features of the independent claim offers the advantage that reliable temperature control, in particular cooling, of the electrical switching device of the battery module can be provided. In particular, such temperature control can be produced directly or directly by means of at least one heat pipe.

[0008] According to the invention, for this purpose a battery module is provided which has a plurality of battery cells which are in particular designed as lithium-ion battery cells.

[0009] The battery module also comprises an electrical switching device, in particular a relay.

[0010] The first terminal of the electrical switching device is electrically conductively connected to one of the plurality of battery cells via the first busbar. In particular, the first busbar is electrically conductively connected to the battery cell and to the first terminal of the electrical switching device. Thus, in particular, an electrical contact is thus formed between the battery cell and the first terminal.

[0011] The second connection of the electrical switching device is connected to the total voltage tapping of the battery module via the second busbar. In particular, the second busbar is conductively connected to the total voltage tapping and to the second connection of the electrical switching device. Therefore, in particular, an electrical contact is formed between the total voltage tapping and the second connection.

[0012] Furthermore, at least one heat pipe is thermally connected to the electrical switching device and the temperature control element.

[0013] Advantageous developments and improvements of the device specified in the independent claim are made possible by the measures listed in the dependent claims.

[0014] In particular, the first busbar is mechanically connected to the battery cell, in particular the voltage tapping of the battery cell, for example, in a material connection, in particular by a welded connection. In addition, the first busbar is mechanically connected to the first voltage tapping of the electrical switching device, in particular, in particular by a welded connection.

[0015] In particular, the second busbar is mechanically connected to the overall voltage tapping of the battery module, for example by a material bond, in particular by a welded connection.

[0016] Furthermore, the second busbar is mechanically connected to the second voltage dividing tap of the electrical switching device, for example, in particular by a materially bonded connection, in particular by a welded connection.

[0017] The electrically conductive connection can thus be formed directly between the first connection and the battery cell via the first busbar and between the second connection and the main voltage tap via the second busbar.

[0018] It should be noted that a heat pipe is to be understood as a heat exchanger, which is also referred to in English as a heat pipe, and which allows a high heat flux density by utilizing the evaporation enthalpy of the medium. Thus, a considerable amount of heat can be transferred over a relatively small cross section. When transferring heat to the heat pipe, the liquid evaporates in the heat pipe, wherein the absorbed heat is transferred via the heat pipe to a temperature regulating body having a relatively small temperature difference. The heat can be discharged from the temperature regulating body by free convection or forced convection.

[0019] It should be noted here that the plurality of battery cells are in particular each constructed as a prismatic battery cell. The prismatically constructed battery cells each comprise a battery cell housing having a total of six side surfaces which are arranged opposite one another in pairs and are substantially parallel to one another. In addition, the side surfaces arranged adjacent to one another are arranged at right angles to one another. The electrochemical components of the corresponding battery cell are accommodated in the interior of the battery cell housing. Two voltage divider taps, such as in particular a positive voltage divider tap and a negative voltage divider tap, are usually arranged on an upper side surface referred to as a cover surface. The lower side surface arranged opposite the upper side surface is referred to as a bottom surface.

[0020] Furthermore, it should be noted that a fuse can be arranged between the second connection and the total voltage tap. In particular, the fuse can be arranged in the second busbar.

[0021] Furthermore, a plurality of battery cells are arranged adjacent to one another, in particular in the longitudinal direction of the battery module. When the battery cells are arranged adjacent to one another in the longitudinal direction of the battery module, the battery cells are arranged adjacent to one another with their respective largest side faces, which are in particular arranged at right angles to the upper side face and the lower side face, respectively. It should be noted that the longitudinal direction of the battery module is therefore arranged perpendicularly to the largest side faces of the battery cells in this case.

[0022] It is advantageous if the at least one heat pipe is arranged to be electrically insulated from the electrical switching device. In particular, the at least one heat pipe is arranged to be electrically insulated from the first connection, the second connection, the first busbar and the second busbar.

[0023] Preferably, the first heat pipe is arranged to be electrically insulated from the first internal joint, and / or the second heat pipe is arranged to be electrically insulated from the second internal joint, and / or the third heat pipe is arranged to be electrically insulated from the first internal joint and the second internal joint, thereby enabling the electrical path and the thermal path to be reliably separated from each other.

[0024] Here, it is advantageous if the electrical insulation is formed by a spacing element that is electrically insulating. The first heat pipe, the second heat pipe and / or the third heat pipe are each accommodated in the spacing element. The spacing element is preferably designed as a plastic injection molded part.

[0025] Furthermore, the electrical insulation can also be formed by means of an electrically insulating compensating element. In particular, the electrically insulating compensating element for electrically insulating the at least one heat pipe from the electrical switching device can be formed as a so-called gap spacer, a so-called gap filler or a thermally conductive adhesive. This offers the advantage that, in addition to electrical insulation, reliable thermal conductivity can also be formed at the same time.

[0026] In particular, for this purpose, for example, a thermally conductive compensating material, known in English as Thermal Interface Material or TIM for short, can also be arranged in the region of the thermal connection between at least one heat pipe and the electrical switching device. The thermally conductive compensating material is hereby designed to be electrically insulating.

[0027] The spacing element and / or the compensating element can preferably comprise an additive which is embodied in a heat-conducting manner, so that the heat transfer can be increased reliably.

[0028] Furthermore, at least one heat pipe can have a maximum circumference to cross-sectional area ratio in the region of the thermal connection between the at least one heat pipe and the electrical switching device. In other words, this means that at least one heat pipe is constructed relatively flat in this region.

[0029] Thereby, the heat transfer can be further increased.

[0030] It is advantageous if a plurality of battery cells are accommodated in a housing of a battery module, wherein the housing is made of plastic. In particular, the housing is designed as a plastic injection-molded part. This offers the advantage that electrical insulation is provided between the plurality of battery cells and the housing of the battery module. Production from plastic also offers the advantage that a considerable degree of freedom can be provided when designing the housing and that the weight can be reduced compared to a housing made of metal.

[0031] Preferably, the electrical switching device can be mechanically connected to the housing of the battery module (eg, the bottom of the housing of the battery module), for example, by a screw connection.

[0032] It is advantageous if the heat-conducting connection between the first heat pipe and the temperature control element and / or between the second heat pipe and the temperature control element and / or between the third heat pipe and the temperature control element is formed in the housing of the battery module. This offers the following advantages: no seal is required between the first heat pipe and the housing of the battery module and between the second heat pipe and the housing of the battery module, and a seal is only formed between the temperature control element and the housing of the battery module. For example, such a seal can be formed by a sealing ring accommodated in a sealing groove.

[0033] In particular, it is possible to adapt the design of the temperature control body in a targeted manner according to the respective requirements, in particular because the temperature control body is not an integral component of the housing.

[0034] If the temperature control body is arranged on the outside of the housing, wherein the temperature control body is in particular designed as an extruded heat sink By arranging the temperature control body on the outside, a reliable heat exchange with the environment of the battery module, in particular with the ambient air, can be provided. In addition, the temperature control body can be arranged at almost any position outside the housing.

[0035] Preferably, the temperature control body can be mechanically connected to the housing of the battery module (eg, the outer side of the housing of the battery module), for example, by means of a screw connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description.

[0037] in:

[0038] Figure 1 An embodiment according to the invention of a battery module is shown in a perspective view;

[0039] Figure 2 The top view shows the Figure 1 A battery module according to an embodiment of the present invention;

[0040] Figure 3 The side cross-sectional view shows Figure 1 A battery module according to an embodiment of the present invention;

[0041] Figure 4 shows the manufacturing steps of the battery module according to the present invention;

[0042] Figure 5 Another manufacturing step of the battery module according to the present invention is shown;

[0043] Figure 6 Another manufacturing step of the battery module according to the present invention is also shown; and

[0044] Figure 7 A cross-sectional view of an embodiment according to the present invention is shown of a battery module. DETAILED DESCRIPTION

[0045] Figure 1 An embodiment according to the invention of a battery module 1 is shown in a perspective view.

[0046] The battery module 1 comprises a plurality of battery cells 2 which are in particular designed as lithium-ion battery cells 20 . Furthermore, the battery cells 2 are in particular designed as prismatic battery cells 200 .

[0047] Furthermore, the battery module 1 comprises an electrical switching device 3 , in particular a relay 30 .

[0048] A plurality of battery cells 2 and in particular also the electrical switching device 3 are accommodated in a housing 7 of the battery module 1. The housing 7 is produced here from a plastic 70. In particular, the housing 7 is designed as a plastic injection-molded part 71.

[0049] The first connection 31 of the electrical switching device 3 is electrically conductively connected to a battery cell 21 of the plurality of battery cells 2 via a first busbar 51 .

[0050] For this purpose, the first busbar 51 is connected, in particular electrically conductively, to the battery cell 21 and the first connection 31 .

[0051] The second connection 32 of the electrical switching device 3 is connected to the battery module 1 via the second busbar 52. Figure 1 The total voltage divider tap 4 which cannot be seen in FIG. 1 is electrically conductively connected.

[0052] For this purpose, the second busbar 52 is connected, in particular electrically conductively, to the total voltage tap 4 and to the second connection 32 .

[0053] Furthermore, at least one heat pipe 6 , in particular a second heat pipe 62 , is connected in a thermally conductive manner to the electrical switching device 3 and the temperature control element 8 .

[0054] Furthermore, the temperature control body 8 is arranged on the outer side 72 of the housing 7 . In particular, the temperature control body 8 is designed as an extruded heat sink 81 .

[0055] Figure 2 The top view shows the Figure 1 The battery module 1 according to an embodiment of the present invention, and Figure 3 The side cross-sectional view shows Figure 1 A battery module 1 according to an embodiment of the present invention.

[0056] Figure 2 and Figure 3 They should be explained together in the following text.

[0057] Firstly, a plurality of battery cells 2 as well as battery cells 21 can be seen here.

[0058] Especially from Figure 3 It can be seen that the second connection 32 of the electrical switching device 3 forms the second internal connection 162 or is connected to the second internal connection 162 .

[0059] Furthermore—not visible in the figure—the first connection 31 of the electrical switching device 3 can also form the first internal connection 161 or be connected to the first internal connection 161 .

[0060] The second heat pipe 62 is hereby connected in a heat-conducting manner to the second internal connection 162 .

[0061] Here, the first heat pipe 61 can also be thermally connected to the first internal connection 161 , and the third heat pipe 63 can be thermally connected to the first internal connection 161 and the second internal connection 162 .

[0062] At least one heat pipe 6 (in particular, a first heat pipe 61 ) is arranged and configured to be electrically insulated from the electrical switching device 3 .

[0063] In this case, in particular the second heat pipe 62 is arranged in an electrically insulated manner to the second internal connection 162 .

[0064] Furthermore, in particular, the first heat pipe 61 can be arranged to be electrically insulated from the first internal connection 161 , and the third heat pipe 63 can be arranged to be electrically insulated from the first internal connection 161 and the second internal connection 162 .

[0065] This electrical insulation 11 is formed here by a compensating element 13 which is designed to be electrically insulating.

[0066] Furthermore, this electrical insulation 11 can be formed here by a spacing element 12 (not visible in the figure) which is designed to be electrically insulating. Here, for example, the first heat pipe 61 , the second heat pipe 62 and / or the third heat pipe 63 can be accommodated in the spacing element 12 .

[0067] from Figure 2 It can also be seen in FIG. 1 that the heat-conducting connection 9 between the second heat pipe 62 and the temperature control body 8 is formed in the housing 7 of the battery module 1 .

[0068] Figure 4 The manufacturing steps of the battery module 1 according to the present invention are shown.

[0069] It can be seen that the second heat pipe 62 is accommodated in the housing 7 together with the compensation element 13 .

[0070] Figure 5 A further production step of the battery module 1 according to the invention is shown.

[0071] It can be seen that the second heat pipe 62 is accommodated in the first accommodation portion 171, and the compensation element 13 is accommodated together with the second heat pipe 62 in the second accommodation portion 172. In particular, the first accommodation portion 171 and the second accommodation portion 172 can reliably position the second heat pipe 62 and the compensation element 13.

[0072] Figure 6 A further production step of the battery module 1 according to the invention is also shown.

[0073] It can be seen here that the electrical switching device 3 is arranged in a housing 7 .

[0074] Figure 7 A sectional view of an embodiment of a battery module 1 according to the invention is shown.

[0075] Here, the second heat pipe 62 and the second internal connection 162 can be seen, between which the compensation element 13 is arranged.

[0076] Furthermore, the second receptacle 172 can also be seen, in which the second heat pipe 62 is received together with the compensation element 13 .

[0077] It can be seen here that a distance can be formed between the second heat pipe 62 and the second internal connection 162 by the second receptacle 172 .

Claims

1. A battery module comprising a plurality of battery cells (2), in particular lithium-ion battery cells (20), and an electrical switching device (3), in particular a relay (30), wherein a first connection (31) of the electrical switching device (3) is electrically conductively connected to a battery cell (21) of the plurality of battery cells (2) via a first busbar (51), and a second connection (32) of the electrical switching device (3) is electrically conductively connected to a total voltage tap (4) of the battery module (1) via a second busbar (52), It is characterized in that At least one heat pipe (6) is thermally connected to the electrical switching device (3) and the temperature control body (8).

2. The battery module according to claim 1, It is characterized in that The first connection (31) of the electrical switching device (3) forms a first internal connection (161) or is connected to the first internal connection (161), and / or the second connection (32) of the electrical switching device (3) forms a second internal connection (162) or is connected to the second internal connection (162), wherein the first heat pipe (61) is thermally connected to the first internal connection (161), and / or the second heat pipe (62) is thermally connected to the second internal connection (162), and / or the third heat pipe (63) is thermally connected to the first internal connection (161) and to the second internal connection (162).

3. The battery module according to any one of the preceding claims 1 to 2, It is characterized in that At least one heat pipe (6) is arranged and configured to be electrically insulated from the electrical switching device (3).

4. The battery module according to claim 2 , It is characterized in that The first heat pipe (61) is arranged and constructed to be electrically insulated from the first internal joint (161), and / or the second heat pipe (62) is arranged and constructed to be electrically insulated from the second internal joint (162), and / or the third heat pipe (63) is arranged and constructed to be electrically insulated from the first internal joint (161) and the second internal joint (162).

5. The battery module according to claim 4, It is characterized in that The electrical insulation (11) is formed by a spacing element (12) which is designed to be electrically insulating, wherein the first heat pipe (61), the second heat pipe (62) and / or the third heat pipe (63) are each accommodated in the spacing element (12).

6. A battery module according to any one of the two preceding claims 4 or 5, It is characterized in that The electrical insulation (11) is formed by a compensating element (13) which is designed to be electrically insulating.

7. The battery module according to any one of the preceding claims 1 to 6, It is characterized in that A plurality of battery cells (2) are accommodated in a housing (7) of a battery module (1), wherein the housing (7) is produced from plastic (70), in particular is designed as a plastic injection-molded part (71).

8. The battery module according to claim 7, It is characterized in that A heat-conducting connection (9) between a first heat pipe (61) and a temperature control body (8) and / or between a second heat pipe (62) and a temperature control body (8) and / or between a third heat pipe (63) and a temperature control body (8) is formed in a housing (7) of a battery module (1).

9. The battery module according to any one of the preceding claims 1 to 8, It is characterized in that The temperature control body (8) is arranged on the outer side (72) of the housing (7), wherein the temperature control body (8) is in particular designed as an extruded heat sink (81).

10. The battery module according to any one of the preceding claims 1 to 9, It is characterized in that At least one heat pipe (6) has a maximum circumference to cross-sectional area ratio in the region of the thermal connection between the at least one heat pipe (6) and the electrical switching device (3).

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