Battery module

Abstract

The invention relates to a battery module comprising a plurality of battery cells (2), in particular lithium-ion battery cells (200), and a battery separation device (3), in particular an overcurrent protection device (30), which has power electronics (4) arranged on an upper side (31) of the battery separation device (3), the at least one heat pipe (5) is connected in a thermally conductive manner to an underside (32) of the battery separation device (3), which underside is arranged facing away from the power electronics (4), and wherein the at least one heat pipe (5) is further connected in a thermally conductive manner to a temperature control body (6).

Description

Technical Field

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

[0002] A battery module usually has a plurality of individual battery cells, each of which has a positive voltage tap and a negative voltage tap, wherein, in order to connect a plurality of battery cells electrically conductively in series and / or in parallel with one another, the respective voltage taps are electrically conductively connected to one another and can thus be connected together to form a battery module. In particular, the battery cells can each have a first voltage tap, in particular a positive voltage tap, and a second voltage tap, in particular a negative voltage tap, which are electrically conductively connected to one another by means of a cell connector, thereby forming an electrical series and / or parallel connection. The battery modules themselves are furthermore connected together to form a battery or an entire battery system.

[0003] The battery disconnect device is in particular an overcurrent protection device, which is used to interrupt the current circuit of the battery module when the current exceeds a certain current intensity, in particular within a predetermined time range. Such a battery disconnect device can be configured as a fuse or a circuit breaker, for example.

[0004] In principle, such a battery disconnect device is preferably actively cooled. For this purpose, such a battery disconnect device can be connected to a heat sink, such as, for example, a cooling channel of a housing made of metal of a battery module.

[0005] Prior art in this regard includes, for example, DE 10 2019 205 388, DE 10 2019 214 199 and DE 10 2019 215 338, which describe cooling of battery disconnect devices by means of a direct thermal connection to a liquid cooler, wherein such a heat sink is an integral component of the housing structure of the housing of the battery module.

[0006] Furthermore, DE 10 2021 204 787 and DE 10 2021 204 696 are also prior art, which each describe heat dissipation via an indirect thermal connection to cooling channels of the housing of the battery module.

[0007] In order to achieve good heat dissipation, the housing of the battery module is preferably made of a metal with relatively good thermal conductivity, preferably as an aluminum die-cast component. Summary of the invention

[0008] A battery module having the features of the independent claim offers the advantage that reliable temperature control, in particular cooling, of the battery disconnect of the battery module can be provided. In particular, such temperature control can be implemented indirectly via the underside of the battery disconnect by means of at least one heat pipe.

[0009] For this purpose, the invention provides a battery module having a plurality of battery cells which are in particular designed as lithium-ion battery cells.

[0010] The battery module further comprises a cell disconnect device, in particular an overcurrent protection device. The cell disconnect device further comprises power electronics, which are arranged on the top side of the cell disconnect device.

[0011] Furthermore, at least one heat pipe is connected to the underside of the battery disconnect device in a heat-conducting manner, wherein the underside is arranged on the battery disconnect device facing away from the power electronics.

[0012] Furthermore, at least one heat pipe is connected to the temperature control element in a heat-conducting manner.

[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] It should be noted that "heat pipe" should be understood as a heat exchanger, which is also called Heatpipe in English, and the heat pipe allows a high heat flux density when using the evaporation enthalpy of the medium. Therefore, a relatively large amount of heat can be transferred on a small cross-section. When the heat is transferred to the heat pipe, the liquid evaporates in the heat pipe, wherein the absorbed heat is transferred to the temperature regulating body by the heat pipe with a relatively low temperature difference. The heat can be output by the temperature regulating body by means of free convection or forced convection. Therefore, at least one heat pipe can then transfer heat from the heat source to the heat absorbing device and thus dissipate the heat of the battery separation device.

[0015] It should be noted here that the plurality of battery cells are in particular each designed as a prismatic battery cell. The prismatically designed battery cells each comprise a battery cell housing having a total of six side surfaces, which are arranged opposite one another in pairs and 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 respective battery cell are accommodated in the interior of the battery cell housing. Two voltage taps, such as in particular a positive voltage tap and a negative voltage tap, are usually arranged on the upper side surface, which is referred to as the cover surface. The lower side surface, which is arranged opposite the upper side surface, is referred to as the bottom surface.

[0016] 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 largest side faces, which are arranged in particular at right angles to the upper side face and to the lower side face, respectively. It should be noted here that the longitudinal direction of the battery module is therefore arranged perpendicularly to the largest side faces of the battery cells in this case.

[0017] Preferably, the battery disconnect device also has a first electrical connection, which is electrically conductively connected to an end battery cell of the plurality of battery cells by means of a first busbar. It is also preferred that the battery disconnect device also has a second electrical connection, which is electrically conductively connected to a total voltage tap, in particular of a battery module, by means of a second busbar.

[0018] In particular, the first busbar is mechanically connected to the battery cells located at the end, in particular to the voltage taps of the battery cells, for example by integral bonding, in particular by means of a welded connection.

[0019] In particular, the second busbar is mechanically connected to the main voltage tap, for example by integral bonding, in particular by means of a welded connection.

[0020] Furthermore, the connection between the first electrical connection and the first busbar and the connection between the second electrical connection and the second busbar are designed mechanically, for example, in an integrally bonded manner, in particular by means of a welded connection.

[0021] Furthermore, the battery module preferably comprises a carrier element, wherein the battery separator is mechanically connected to the carrier element. Furthermore, at least one heat pipe is arranged between the battery separator and the carrier element. As a result, a reliable thermal contact can be established between the at least one heat pipe and the battery separator. For this purpose, the carrier element can preferably comprise a receiving portion, which is configured to receive at least one heat pipe.

[0022] In this case, the support element can be mechanically connected to the housing of the battery module, for example, by means of a screw connection.

[0023] According to a preferred concept of the present invention, the mechanical connection between the battery disconnect device and the support element is designed as a heat-riveted connection. Such a heat-riveted connection can reliably ensure thermal contact during operation.

[0024] Advantageously, at least one heat pipe is arranged in a manner electrically insulated from the battery disconnect device. In particular, the current path or the current-conducting region of the battery disconnect device is electrically insulated from the at least one heat pipe. As a result, the electrical path and the thermal path can be reliably separated from each other.

[0025] It is expedient if a thermal compensation material is also arranged between the battery disconnect device and the at least one heat pipe. This allows an improved thermal contact to be formed between the at least one heat pipe and the battery disconnect device. In particular, the thermal compensation material can also be designed to be electrically insulating. In addition, the thermal compensation material can also be arranged between the at least one heat pipe and the temperature control body.

[0026] The electrical insulation described here can then be formed by means of a compensation element which is preferably formed in an electrically insulating manner.

[0027] Preferably, the compensating element can include an additive that is embodied in a thermally conductive manner, so that the heat transfer can be increased reliably.

[0028] Advantageously, 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 an injection molded part. This provides the advantage that electrical insulation is provided between the plurality of battery cells and the housing of the battery module. In addition, the advantages provided by the plastic construction are that relatively large freedom can be provided when designing the housing and that the weight can be reduced compared to a housing made of metal. In particular, the advantages provided by the embodiments of the present invention according to the present invention are that even in the case of a housing made of a material with relatively low thermal conductivity, reliable heat dissipation of the battery separator can be provided.

[0029] The battery disconnect device can preferably be mechanically connected to the housing of the battery module, for example by means of a screw connection.

[0030] Advantageously, the heat-conducting connection between the at least one heat pipe and the temperature control element is formed in the housing of the battery module. This offers the advantage that no seal is required between the at least one heat pipe and the housing of the battery module, and only a seal is formed between the temperature control element and the housing of the battery module. Such a seal can be formed, for example, by means of a sealing element received in a sealing groove.

[0031] In particular, it is possible to specifically adapt the design of the heating element to the respective requirements, in particular because the heating element is not an integral component of the housing.

[0032] Advantageously, the temperature control body is arranged on the outside of the housing, wherein the temperature control body is in particular designed as an extruded cooling body, a die-cast cooling body or an impact-extruded cooling body. The arrangement of the temperature control body on the outside can provide a reliable heat exchange with the surroundings of the battery module, in particular the surrounding air. In addition, in particular because the at least one heat pipe can also work against gravity, the temperature control body can be arranged almost arbitrarily on the outside of the housing as a heat sink.

[0033] The temperature control body is preferably made of a material with a relatively high thermal conductivity and a relatively large surface, so that a reliable heat transfer to the surrounding environment is established. In particular, the temperature control body can be made of aluminum, copper and / or a copper alloy. In addition, the temperature control body can have ribs that increase the surface of the temperature control body. The heat transfer between the temperature control body and the surrounding air can be achieved by forced convection or free convection.

[0034] The temperature control body can preferably be mechanically connected to the housing of the battery module, for example the outer side of the housing of the battery module, for example by means of a screw connection. In particular, a sealing element can be pressed in for sealing when the screw connection is formed.

[0035] The advantages provided by the embodiments of the present invention are that the power electronic components to be temperature-controlled, in particular to be cooled, are indirectly connected to at least one heat pipe, wherein the power electronic components are arranged on the upper side of the battery disconnect device and at least one heat pipe is arranged on the lower side of the battery disconnect device, so that an indirect heat-conducting connection is formed through the battery disconnect device.

[0036] Finally, it should also be noted here that the heat for cooling the battery disconnect device can then be transferred, in particular from the power electronics through the battery disconnect device, preferably by means of a thermal compensation material, to the at least one heat pipe and subsequently from the at least one heat pipe, in particular by means of a thermal compensation material, to the temperature control body. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description.

[0038] in:

[0039] Figure 1 An embodiment of a battery module according to the invention is shown in a perspective view.

[0040] Figure 2 An embodiment of a battery module according to the invention is shown in a sectional view from the side.

[0041] Figure 3 The steps of manufacturing a battery module according to the present invention are shown, and

[0042] Figure 4 Further steps for producing a battery module according to the invention are shown. DETAILED DESCRIPTION

[0043] Figure 1 An embodiment according to the invention of a battery module 1 is shown in a perspective view.

[0044] The battery module 1 comprises a plurality of battery cells 2 which are preferably designed as lithium-ion battery cells 200 . In particular, the battery cells 2 are also each designed as a prismatic battery cell 20 .

[0045] A plurality of battery cells 2 are accommodated in a housing 8 of the battery module 1 . In particular, the housing 8 is made of plastic 80 , preferably in the form of an injection-molded part 81 .

[0046] Furthermore, the battery module 1 comprises a battery disconnect device 3 which is designed in particular as an overcurrent protection device 30 .

[0047] The battery disconnect device 3 has a top side 31 and a bottom side 32 arranged opposite the top side 31 and disposed at a position adjacent to the top side 31. Figure 1 Not visible in.

[0048] The battery disconnect device 3 also has a first electrical connection 36, which is electrically conductively connected to the battery cells 21 at the ends of the plurality of battery cells 2 by means of a first busbar 71. The battery disconnect device 3 also has a second electrical connection 37, which is electrically conductively connected to the battery cells 21 at the ends of the plurality of battery cells 2 by means of a first busbar 71. Figure 1 The second busbar 72 not shown in the figure is connected to the battery module 1 in Figure 1 The main voltage tap, which is also not shown, is connected in an electrically conductive manner.

[0049] The power electronics 4 are arranged on the top side 31 of the battery disconnect device 3 .

[0050] At least one heat pipe 5 is connected in a heat-conducting manner to the bottom side 32 of the battery disconnect device 3. It should also be noted here that the bottom side 32 of the battery disconnect device 3 is arranged facing away from the power electronics 4.

[0051] In particular, according to Figure 1 The embodiment of FIG. 1 has two heat pipes 5 .

[0052] In this case, the heat pipe 5 is also connected in a heat-conducting manner to a temperature control body 6 . The temperature control body 6 is arranged here on an outer side 82 of the housing 8 of the battery module 1 .

[0053] Furthermore, the temperature control body 6 can preferably be designed as an extruded cooling body 61 .

[0054] The heat-conducting connection 9 between the heat pipe 5 and the temperature control body 6 is formed in this case in the housing 8 of the battery module 1 .

[0055] Figure 2 An embodiment according to the invention of a battery module 1 is shown in a sectional view from the side.

[0056] Here, firstly the battery disconnect device 3 with the power electronics 4 can be seen. Furthermore, the top side 31 and the bottom side 32 can also be seen.

[0057] As already described, at least one heat pipe 5 is arranged in this case in a heat-conducting manner on the underside 32 of the battery disconnect device 3 .

[0058] The battery module 1 further comprises a support element 11 , wherein the battery disconnect device 3 is mechanically connected to the support element 11 . In this case, at least one heat pipe 5 is arranged between the battery disconnect device 3 and the support element 11 .

[0059] Such a mechanical connection is preferably designed as a heat-riveted connection 10 .

[0060] In this case, the at least one heat pipe 5 is designed to be electrically insulated from the battery disconnect device 3 .

[0061] In this case, a first thermal compensation material 15 is arranged between the battery disconnect device 3 and the at least one heat pipe 5 , which first thermal compensation material is also preferably designed to be electrically insulating.

[0062] Furthermore, a second thermal compensation material 16 is arranged between the at least one heat pipe 5 and the temperature control body 6 .

[0063] In addition, Figure 2 The individual heat transfer processes are shown in FIG. 1 by means of arrows. Heat is then transferred from the battery disconnect device 3 to the at least one heat pipe 5 , conducted in the at least one heat pipe 5 , transferred from the at least one heat pipe 5 to the temperature control body 6 and from the temperature control body 6 to the surroundings.

[0064] Figure 3 The steps for manufacturing a battery module 1 according to the invention are shown, and Figure 4 Further steps for producing a battery module 1 according to the invention are shown.

[0065] Here, in Figure 3 The arrangement of the heat pipes 5 can be seen in FIG. 1 . Furthermore, a carrier element 11 can be seen, which has at least one receptacle 12 or a plurality of receptacles 12 in which at least one heat pipe 5 or a plurality of heat pipes 5 can be received in each case.

[0066] The support element 11 is connected to the housing 8 of the battery module 1 by means of a screw connection 13 .

[0067] Furthermore, at least one heat pipe 5 or a plurality of heat pipes 5 each have a deflection 14 which is designed, in particular, at a right angle.

[0068] Furthermore, it can be seen that at least one heat pipe 5 or a plurality of heat pipes 5 are of relatively flat design in the connecting region 18 and have, in particular, a rectangular cross section.

[0069] Depend on Figure 4 It can be seen that a first thermal compensation element 15 is arranged between the battery disconnect device 3 and the at least one heat pipe 5 or a plurality of heat pipes 5 .

[0070] The cell disconnect device 3 and the carrier element 11 are connected to one another by means of a heat-riveted connection 10 .

[0071] Furthermore, the carrier element 11 has a supporting element 19 which is designed to accommodate or support the battery disconnect device 3 on the carrier element 11 .

Claims

1. A battery module comprising a plurality of battery cells (2), in particular lithium-ion battery cells (200), and a battery disconnect device (3), in particular an overcurrent protection device (30), the battery disconnect device having a power electronic device (4) arranged on the upper side (31) of the battery disconnect device (3), It is characterized in that At least one heat pipe (5) is thermally conductively connected to a bottom side (32) of the battery disconnect device (3) which is arranged facing away from the power electronics (4), and the at least one heat pipe (5) is also thermally conductively connected to a temperature control element (6).

2. The battery module according to claim 1, It is characterized in that The battery disconnect device (3) also has a first electrical connection (36) which is electrically conductively connected to the battery cells (21) located at the ends by means of a first busbar (71) and a second electrical connection (37) which is electrically conductively connected to a total voltage tap of the battery module by means of a second busbar (72).

3. The battery module according to any one of the preceding claims 1 to 2, It is characterized in that The battery module (1) further comprises a carrier element (11), wherein the battery separator (3) is mechanically connected to the carrier element (11), and the at least one heat pipe (5) is arranged between the battery separator (3) and the carrier element (11).

4. The battery module according to claim 3, It is characterized in that The mechanical connection between the battery separator (3) and the supporting element (11) is constructed as a hot riveted connection (10).

5. The battery module according to any one of the preceding claims 1 to 4, It is characterized in that The at least one heat pipe (5) is designed to be electrically insulated from the battery disconnect device (3).

6. The battery module according to any one of the preceding claims 1 to 5, It is characterized in that Furthermore, a thermal compensation material (15) is arranged between the battery disconnect device (3) and the at least one heat pipe (5), which thermal compensation material is in particular 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 The plurality of battery cells (2) are accommodated in a housing (8) of the battery module (1), wherein the housing (8) is made of plastic (80), in particular is designed as an injection-molded part (81).

8. The battery module according to claim 7, It is characterized in that A heat-conducting connection (9) between the at least one heat pipe (5) and the temperature control body (6) is formed in a housing (8) of the 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 (6) is arranged on an outer side (82) of the housing (8), wherein the temperature control body (6) is in particular designed as an extruded cooling body (61).

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