Battery module of a high-voltage battery for an electric vehicle

Abstract

Battery module (1) of a high-voltage battery for an electric vehicle, wherein the battery module (1) comprises a battery module housing (2) and a plurality of battery cells (3) arranged in the battery module housing (2), wherein the battery module housing (2) comprises a central part (4) with a cavity in which the battery cells (3) are arranged, and an end plate (5) arranged at each of two axial ends of the central part (4), wherein the respective end plate (5) has several attachment points (6) oriented transversely to a principal extension plane of the central part (4) for attaching the battery module (1), characterized in that at least one of the end plates (5) has an inner wall (9) connected to the central part (4), a central deformable area (10) and an outer area (11) with the attachment points (6) for attaching the battery module (1).

Description

[0001] The invention relates to a battery module of a high-voltage battery for an electric vehicle, wherein the battery module comprises a battery module housing and a plurality of battery cells arranged in the battery module housing, wherein the battery module housing comprises a central part with a cavity in which the battery cells are arranged, and an end plate arranged at each of two axial ends of the central part, wherein the respective end plate has several attachment points oriented transversely to a principal extension plane of the central part for fastening the battery module.

[0002] In an electrically or partially electrically powered vehicle, numerous battery cells are connected together to form a traction battery, according to the current state of the art. The complete battery, and thus the traction battery, consists of more than one hundred, sometimes up to several thousand, battery cells. The battery cells of a traction battery are connected to form subgroups, in this case battery modules, which usually each contain the same number of battery cells and are interconnected to form the traction battery.

[0003] Battery modules, in addition to a specific number of electrically connected battery cells, comprise a battery module housing that mechanically holds, secures, and protects the battery cells. According to current technology, battery module housings are made of metal or plastic. They often consist of a central section that encloses the battery cells and end plates that close the housing and typically serve to mechanically secure the battery module. To this end, the end plate often features vertical through-holes, particularly two vertical through-holes. The end plate is made of cast aluminum, plastic, sheet metal, or a combination of metal and plastic.

[0004] Of particular importance in the design of battery modules is that they, and especially the battery cells of the battery module, remain largely undamaged in the event of a vehicle crash.

[0005] CN 108923000 describes a battery with a crash structure.

[0006] German patent DE 20 2016 100 631 U1 describes a double-walled battery housing. A cavity is provided between an inner wall and an outer wall of the battery housing. The outer wall has a corrugated design.

[0007] DE 10 2011 005 403 A1 discloses a battery housing for an underfloor battery of a vehicle, wherein a housing wall facing a roadway is partially double-walled, with the double-walled sections defining a cavity.

[0008] DE 20 2016 100 629 U1 discloses a double-walled battery housing, wherein a cavity is provided between an inner wall and an outer wall, and wherein cylindrical, stiffened hollow bodies are arranged in the cavity.

[0009] Documents EP 1 939 028 A1 and EP 2 837 048 A1 disclose a battery which is arranged in a battery frame, the battery frame serving to protect the battery in the event of a crash.

[0010] The object of the present invention is to further develop a battery module having the features of the preamble of claim 1 in such a way as to prevent damage to the battery cells in the event of a crash.

[0011] The problem is solved by a battery module designed according to the features of claim 1.

[0012] The high-voltage battery module comprises a battery module housing and a plurality of battery cells arranged within the battery module housing. The battery module housing has a central section with a cavity in which the battery cells are arranged, as well as two end plates located at each of the axial ends of the central section. Each end plate has several mounting points oriented transversely to a principal plane of extension of the central section for attaching the battery module. At least one of the end plates has an inner wall connected to the central section, a central deformable area, and an outer area with the mounting points for attaching the battery module.

[0013] This design of the battery module results in less intrusion into the inner area of ​​the battery module housing requiring protection in the event of a crash. The load is introduced into the battery module housing, and particularly into the central section, in such a way that the mounting points as a whole are slightly shifted inwards during the crash, preventing the fasteners located at each mounting point from undergoing deformation that would lead to failure, especially breakage. The significant deformation occurs in the central deformable area of ​​the end plate.

[0014] To determine after an accident whether a battery module has been damaged and needs to be replaced or can continue to be used, the inventive design of the battery module allows for inspection of the central deformable area between the end plate and the mounting points for attaching the battery module. If this central deformable area is deformed, the battery module must be replaced. If this area is not deformed, the battery module can continue to be used.

[0015] Furthermore, it is advantageous that the central deformable area deforms at a lower load level when force is applied, leaving the inner part of the battery module undamaged. This means that only those battery modules with damage to the deformation zone need to be replaced, thus saving customers repair costs.

[0016] Preferably, both end plates each have the inner wall connected to the middle part, the middle deformable area and the outer area with the attachment points for attaching the battery module.

[0017] The battery module housing is arranged, with respect to its longitudinal direction, particularly in a transverse direction of the electric vehicle. In terms of a typical orientation, this corresponds to a Y-direction of the electric vehicle, defining a longitudinal direction X and a vertical direction Z.

[0018] The end plate is specifically designed as an extruded profile. This is preferably an aluminum extrusion profile.

[0019] The end plate is arranged in particular with an extrusion direction of the end plate in the vertical direction Z of the electric vehicle.

[0020] The deformable area is advantageously formed by at least one hollow chamber arranged between the components forming the fastening points and the inner wall. The area, which is particularly deformable in a Y-direction, is thus formed by the at least one hollow chamber arranged, in particular, between external mechanical fastening points and the inner wall.

[0021] In particular, a space for the battery cells within the battery module is enclosed by the central part and the inner walls.

[0022] The inner wall is advantageously mechanically connected to the central section. This allows for easy assembly and disassembly of the inner wall relative to the central section. This is beneficial both during assembly and repair of the battery module.

[0023] It is also advantageous if the inner wall is sealed to the central section. The inner wall of the end plate, together with the central section of the battery module housing, seals the battery cells against media and environmental influences.

[0024] The battery module is mechanically fastened primarily via through-holes in the outer area of ​​the end plate. A screw connection is particularly advantageous here, as it is easy to make and also easy to remove.

[0025] In particular, the through holes form cavities of screw bosses and / or the central deformable area forms cavities that are formed between the screw bosses and the inner wall.

[0026] The screw-on domes are connected to the inner wall, in particular by means of webs. Preferably, the screw-on domes are integrally connected to the inner wall by means of these webs.

[0027] Furthermore, it is advantageous if the webs are arranged diagonally or in an arc between the mounting bosses and the inner wall. The webs are thus not positioned along the shortest direct paths, but diagonally or in an arc, allowing a reduction in the distance between the mounting bosses and the inner wall by means of plastic deformation of the deformation zone and the associated reduction in the size of the cavities forming the deformation zones, without significantly pressing the inner wall into the interior of the battery module containing the battery cells.

[0028] Furthermore, it is advantageous if the end plate has a flat extruded outer wall that forms a further cavity with the inner wall and the webs surrounding the through-holes. Thus, the outer wall is only indirectly connected to the inner wall, and a cavity open in opposite directions, in particular a cavity open at the top and bottom, is formed between the inner and outer walls.

[0029] The term "hollow chamber" used above should also be understood in this context. A hollow chamber can be formed by an open cavity.

[0030] According to an advantageous embodiment, webs can extend inwards from the inner wall into the central section, creating a favorable positive fit in the event of a crash. In particular, these webs are extruded webs joined in one piece, projecting inwards in the Y-direction and forming a favorable positive fit in the event of a crash, when loaded from the front, i.e., in the X-direction.

[0031] Key advantages of the battery module according to the invention, along with its further developments, are robust crash behavior, weight reduction and cost reduction in the event of repairs.

[0032] Further features of the invention will become apparent from the dependent claims, the accompanying drawing and the description of the embodiments shown in the drawing, without being limited thereto.

[0033] It shows: Fig. 1 A first embodiment of a battery module of a high-voltage battery, illustrated in a spatial representation, Fig. 2 a section through the battery module in the area of ​​one of the two end plates of the battery module, cut in an XY plane, Fig. 3 A second embodiment of a battery module of a high-voltage battery, illustrated in a spatial representation, Fig. 4 a cut through the in Fig. 3 Battery module shown in the area of ​​one of the two end plates of the battery module, cut in an XY plane. Character description

[0034] The Fig. 1 and Fig. Figure 2 shows a battery module for the first embodiment. 1 a high-voltage battery for a motor vehicle. The battery module 1 a battery module housing 2 and a plurality in the battery module housing 2arranged battery cells 3 on. The battery module housing 2 has a middle section 4 with a cavity in which the battery cells 3 are arranged, as well as one at each of the two axial ends of the central part 4 , relative to the Y-axis, arranged end plates 5 up. From these two end plates 5 is just an end plate 5 To illustrate, the other end plate is identically designed. The respective end plate 5 exhibits several, perpendicular to a main extension plane XY of the middle part 4 aligned, thus Z-direction aligned, mounting points 6 for attaching the battery module 1 on.

[0035] The battery module housing 2 is divided by two parallel narrow side walls 7 and these connecting, parallel, wider side walls 8 formed. Thus, the battery module housing2 The front face, open in the area of ​​the two XZ planes. The middle section is located there. 4 by means of the two mechanically connected middle parts 4 connected end plates 5 sealed. The end plates 5 seal the middle section 4 away.

[0036] The respective end plate 5 has an interior wall 9 , which connects to the middle part 4 represents, furthermore, a medium deformable area 10 and an outer area 11 with the attachment points 6 for attaching the battery module 1 up. The mounting of the battery module 1 This takes place at a battery box or on the body of the electric vehicle.

[0037] The end plate 5 It is designed as an extruded profile, specifically as an aluminum extrusion profile. The extrusion direction of the end plate 5is in the Z-direction. The deformable area 10 has a hollow chamber 12 open in the Z-direction. The hollow chamber 12 is between the inner wall 9 and the respective attachment point 6 arranged. The space for the battery cells 3 within the battery module 1 is through the middle part 4 and the two end plates 5 enclosed.

[0038] The mounting of the battery module 1 in the area of ​​the two end plates 5 assigned four attachment points 6 This is done mechanically, in particular by means of a screw connection. For this purpose, the area of ​​the respective fastening point is marked accordingly. 6 a screw-on dome 13 a through hole 14 in the Z-direction. The central deformable area 9 furthermore, it points between the inner wall 9 and the two screw-on bosses associated with these13 another cavity 15 on.

[0039] The screw-on domes 13 are by means of bridges 16 one piece with the inner wall 9 connected. The respective bridge 16 runs in an arc shape between the associated screw-on dome 13 and the inner wall 9 .

[0040] The end plate 5 It also has a flat outer wall 17 on, which the cavity 15 at a distance from the inner wall 9 and the screw-on domes 13 limited. Screws for connecting the end plate 5 with the middle part 4 are with the reference number 18 designated.

[0041] In this embodiment, the outer wall connects 17 the screw-on domes 13 . In the inner wall 9 far-facing area of ​​the bridges 19 are these on the outer wall 17 far side of the screw-on bosses 13with the screw-on domes 13 connected and furthermore with the inner wall 9 connected in the area of ​​their far ends, relative to their extension in the X direction. The webs 19 This contributes to further stiffening of the end plate. 5 at.

[0042] Regarding the battery module 1 are with the reference number 20 Areas of electrical contacts of the battery module 1 illustrated.

[0043] The second embodiment according to the Fig. 3 and Fig. 4 differs from the one according to the Fig. 1 and Fig. 2 essentially by the fact that it is not an exterior wall 17 and no bridges 19 features. The bridges 16 are not in the inner wall 9 facing area of ​​the respective screw dome 13 arranged, but rather engage at the respective screw-on dome. 13 on whose inner wall 9opposite side. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] CN 108923000

[0005] DE 202016100631 U1

[0006] DE 102011005403 A1

[0007] DE 202016100629 U1

[0008] EP 1939028 A1

[0009] EP 2837048 A1

[0009]

Claims

[1] Battery module (1) of a high-voltage battery for an electric vehicle, wherein the battery module (1) comprises a battery module housing (2) and a plurality of battery cells (3) arranged in the battery module housing (2), wherein the battery module housing (2) comprises a central part (4) with a cavity in which the battery cells (3) are arranged, and an end plate (5) arranged at each of two axial ends of the central part (4), wherein each end plate (5) has several attachment points (6) oriented transversely to a principal extension plane of the central part (4) for attaching the battery module (1), characterized by , that at least one of the end plates (5) has an inner wall (9) connected to the middle part (4), a middle deformable area (10) and an outer area (11) with the attachment points (6) for attaching the battery module (1). [2] Battery module according to claim 1, characterized by, that both end plates (5) each have the inner wall (9) connected to the middle part (4), the middle deformable area (10) and the outer area (11) with the attachment points (6) for attaching the battery module (1). [3] Battery module according to claim 1 or 2, characterized by a battery module housing (2) which is arranged in the longitudinal direction in a transverse direction (Y) of the electric vehicle. [4] Battery module according to any one of claims 1 to 3, characterized by , that the end plate (5) is designed as an extrusion profile. [5] Battery module according to claim 4, characterized by , that the end plate (5) is designed as an aluminum extrusion profile. [6] Battery module according to claim 4 or 5, characterized by an end plate (5) with extrusion direction of the end plate (5) in a vertical direction (Z) of the electric vehicle. [7] Battery module according to any one of claims 1 to 6, characterized by, that the deformable area (10) is formed by at least one hollow chamber (12) which is arranged between the components forming the attachment points (6) and the inner wall (9). [8] Battery module according to any one of claims 1 to 7, characterized by , that a space for the battery cells (3) within the battery module (1) is enclosed by the middle part (4) and the inner walls (9). [9] Battery module according to any one of claims 1 to 8, characterized by , that the inner wall (9) is mechanically connected to the middle part (4). [10] Battery module according to any one of claims 1 to 9, characterized by , that the inner wall (9) is sealed and connected to the middle part (4). [11] Battery module according to any one of claims 1 to 10, characterized by , that the battery module (1) is attached mechanically. [12] Battery module according to claim 11, characterized by, that the mechanical fastening of the battery module (1) is carried out via through holes (14) in outer areas of the end plate (5). [13] Battery module according to claim 12, characterized by that the mechanical fastening is done by means of a screw connection. [14] Battery module according to claim 12 or 13, characterized by , that the through holes (14) form cavities of screw bosses (13) and / or the central deformable area (10) forms cavities (12) that are formed between the screw bosses (13) and the inner wall (9). [15] Battery module according to claim 14, characterized by , that the screw-on domes (13) are connected to the inner wall (9) by means of webs (16). [16] Battery module according to claim 15, characterized by , that the screw-on domes (13) are connected in one piece to the inner wall (9) by means of the webs (16). [17] Battery module according to claim 15 or 16, characterized by, that the webs (16) are arranged diagonally or in an arc shape between the screw-on bosses (13) and the inner wall (9). [18] Battery module according to any one of claims 12 to 17, characterized by , that the end plate (8) has a flat outer wall (17) which forms a further cavity (15) with the inner wall (9) and the screw bosses (13). [19] Battery module according to any one of claims 1 to 18, characterized by , that the webs connected to the inner wall (9) extend into the middle part (4).

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