Battery module of a traction battery and traction battery

Abstract

Battery module (10) of a traction battery of a motor vehicle, comprising a battery module housing (11) which has a first housing wall (16) and a second housing wall (17) opposite the first housing wall (16), with several battery cells (12) arranged in a stack-like manner in the battery module housing (11) such that a stacking direction of the battery cells (12) extends parallel to the first and second housing walls (16, 17), wherein a preloading element (18) is arranged between each battery cell (12) and the first housing wall (16), wherein a positioning element (19) is arranged between each battery cell (12) and the second housing wall (17), wherein at least one degassing opening (20, 21) is provided in the second housing wall (17) and in the positioning element (19) for each battery cell (12),wherein the respective preloading element (18) presses the respective battery cell (12) against the positioning element (19) in the direction of the respective at least one degassing opening (20, 21) towards the second housing wall (17), wherein, viewed in the stacking direction of the battery cells (12), a cooling plate (15) is arranged on both sides of each battery cell (12), and wherein the preloading element (18) and the positioning element (19), which is assigned to a respective battery cell (12), fix one of the cooling plates (15) assigned to the respective battery cell (12) in its position.

Description

[0001] The invention relates to a battery module of a traction battery and a traction battery.

[0002] EP 2 843 729 A1 discloses a battery module with a battery module housing and a plurality of battery cells arranged in a stack within the battery module housing. The battery module housing has a receiving part with a bottom wall and side walls. A cover with recesses is arranged opposite the bottom wall of the receiving part. Connection terminals of the battery cells extend through first openings in the cover. Second openings in the cover are aligned with degassing areas of the battery cells. Prestressing elements for prestressing the battery cells are arranged on the bottom wall of the receiving part.

[0003] DE 10 2011 077 331 A1 and US 9 928 965 B2 disclose further prior art.

[0004] DE 10 2021 129 317 A1 discloses a battery module of a traction battery according to the preamble of claim 1.

[0005] DE 10 2022 112 014 A1, DE 10 2014 218 126 A1, DE 10 2008 059 953 A1 and DE 10 2018 114 226 A1 disclose further prior art.

[0006] There is a need for a battery module with improved battery cell containment and alignment.

[0007] Based on this, the present invention is based on the object of creating a novel battery module of a traction battery and a traction battery with such a battery module.

[0008] This object is achieved by a battery module of a traction battery according to claim 1 and a traction battery according to claim 8.

[0009] The battery module according to the invention has a battery module housing which has a first housing wall and a second housing wall opposite the first housing wall.

[0010] The battery module according to the invention has a plurality of battery cells arranged in a stack in the battery module housing such that a stacking direction of the battery cells extends parallel to the first and second housing walls.

[0011] A prestressing element is arranged between each battery cell and the first housing wall of the battery module according to the invention.

[0012] A positioning element is arranged between each battery cell and the second housing wall of the battery module according to the invention.

[0013] At least one degassing opening is introduced into the second housing wall and into the positioning element for each battery cell of the battery module according to the invention, wherein the respective prestressing element presses the respective battery cell with its respective at least one degassing region against the positioning element in the direction of the second housing wall, aligning the same with the respective at least one degassing opening of the positioning element and the second housing wall.

[0014] Viewed in the stacking direction of the battery cells, a cooling plate is arranged on each side of each battery cell. The preloading element and the positioning element assigned to a respective battery cell fix one of the cooling plates assigned to the respective battery cell in its position, preferably the cooling plate arranged in front of the respective battery cell in the stacking direction. The preloading elements and positioning elements not only improve the alignment of the battery cells in the battery module, but also advantageously fix the cooling plates in the battery module.

[0015] The battery module according to the invention allows for improved accommodation and alignment of the battery cells.

[0016] Preferably, the first housing wall and the second housing wall have ribs on a side associated with the battery cells, which extend transversely to the stacking direction of the battery cells, wherein the ribs have a groove-like profile on a side facing the stacking direction. Holding devices of the cooling plates engage in the groove-like profiles of the ribs, wherein a prestressing element is arranged in the region of the first housing wall between each two immediately adjacent ribs of the first housing wall, and a positioning element is arranged in the region of the second housing wall between each two immediately adjacent ribs of the second housing wall.The retaining devices of each cooling plate are secured by a preloading element and a positioning element in the groove-like profiles of the ribs on the first housing wall and the second housing wall, namely in the area of ​​the first housing wall via a preloading element and in the area of ​​the second housing wall via a positioning element. This makes it possible to alternately arrange cooling plates and battery cells in the battery module housing and to alternately fix, preload, and align them using the preloading elements and positioning elements.

[0017] Preferably, each preload element has a preload section for the respective battery cell to be preloaded and a positioning section for a holding device of the respective cooling plate to be fixed, wherein a cavity is formed between the preload section and the positioning section. Such preload elements are particularly suitable for providing, on the one hand, the preload function for the respective battery cell and, on the other hand, the positioning function for the respective cooling plate.

[0018] Preferably, each biasing element and each positioning element has a projection arranged between a respective rib and a respective battery cell. These projections can prevent direct contact of the respective battery cell with a rib of the first and second housing walls.

[0019] Preferred developments of the invention will become apparent from the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail, without being limited thereto, with reference to the drawings. Herein: Fig. 1 a section of a battery module in the area of ​​a battery cell and two cooling plates, Fig. 2 a detail of the battery module, Fig. 3 another detail of the battery module, Fig. 4 a perspective section of a detail of the battery module, Fig. 5 another perspective section of a detail of the battery module, Fig. 6 a detail of the battery module to illustrate the assembly of the battery module, Fig. 7 the detail of the Fig. 7 to further clarify the assembly of the battery module Fig. 8 the detail of the Fig. 7 to further clarify the assembly of the battery module.

[0020] The invention relates to a battery module 10 of a traction battery of a motor vehicle. Fig. 1 shows a section of a battery module 10 in the area of ​​a battery module housing 11 and a battery cell 12 positioned in the battery module housing 11. Of the battery cell 12 are in Fig. 1 shows a cell housing 13 and a cell coil 14 accommodated in the cell housing 13. The battery module 10 is a high-voltage battery module.

[0021] Furthermore, Fig. 1 cooling plates 15 are shown, with a cooling plate 15 being arranged on each side of a battery cell 12. Fig. The right-hand cooling plate 15 shown in Figure 1 is followed by another battery cell 12, this additional battery cell 12 is followed by another cooling plate 15, and this additional cooling plate 15 is followed by another battery cell 12, and so on. The battery cells 12, together with the cooling plates 15, are thus arranged in a stack in the battery module housing 11.

[0022] A first housing wall 16 and a second housing wall 17 of the battery module housing 11 are shown, wherein in the installed position of the battery module 10 in the motor vehicle, the first housing wall 16 is an upper housing wall and the second housing wall 17 is a lower housing wall of the battery module housing 10.

[0023] According to Fig. 1 is between the Fig. 1 and the first housing wall 16, a biasing element 18 and between the in Fig. A positioning element 19 is arranged between the battery cell 12 shown in Figure 1 and the second housing wall 17. This is provided in the area of ​​each battery cell 12.

[0024] At least one degassing opening 20 and 21, respectively, is introduced into the second housing wall 17 and into the positioning element 19 for the respective battery cell 12, which interact with at least one respective degassing region 22 of the respective battery cell 12.

[0025] The respective prestressing element 18 presses the respective battery cell 12 perpendicularly or orthogonally to the direction of extension thereof in the direction of the second housing wall 17 against the positioning element 19.

[0026] During operation, the battery cells 12 are subject to expansion caused by a pressure change within the battery cells 12. This expansion typically occurs in the stacking direction of the battery cells 12 within the battery module housing 11.

[0027] Then, when the pressure within a battery cell 12 becomes too great, the at least one degassing region 22 of the battery cell 12, namely the cell housing 13 of the respective battery cell 12, breaks in order to degas the respective battery cell 12 via the degassing openings 20, 21 of the second housing wall 17 and the respective positioning element 19.

[0028] In the exemplary embodiment shown, the degassing openings 21 in the positioning element 19 are initially closed by a wall section 23, which then opens when the degassing area 22 of the respective battery cell 12 has opened as a result of an overpressure in the respective battery cell 12.

[0029] Each battery cell 12 is accordingly clamped by a respective pre-tensioning element 18 and pressed by the respective pre-tensioning element 18 in the direction of the second housing wall 17 against the respective positioning element 19, specifically aligning the battery cell 12, namely its at least one degassing region 22, with the degassing openings 20, 21 of the second housing wall 17 and the respective positioning element 19.

[0030] As already explained, a cooling plate 15 is arranged on both sides of each battery cell 12 within the battery module housing 11, as viewed in the stacking direction of the battery cells 12. The preloading element 18 and the positioning element 19 of each battery cell 12 interact not only with the respective battery cell 12, but also with at least one cooling plate 15 assigned to the respective battery cell 12, namely with the cooling plate 15 that is arranged in front of the respective battery cell 12 as viewed in the stacking direction of the battery cells 12. Thus, the respective cooling plate 15, which is arranged in front of a respective battery cell 12 in the stacking direction, is fixed in its position in the battery module housing 11 by the preloading element 18 and the positioning element 19 that interact with this battery cell 12.

[0031] How best Fig. 2 and Fig. 3, both the first housing wall 16 and the second housing wall 17 have the same ribs 24 and 25, respectively, on a side facing the battery cells 12. The ribs 24, 25 of the two housing walls 17, 18 extend parallel to one another at a distance transversely to the stacking direction of the battery cells 12.

[0032] Each of the ribs 24, 25 has a groove-like profile 26, 27 on a side facing the stacking direction. Holding devices 28 for the cooling plates 15 engage in sections in the groove-like profiles 26, 27 of the ribs 24, 25 of the housing walls 16, 17, wherein these holding devices 28 are fixed in the groove-like profiles 26, 27 via a respective prestressing element 18 and a respective positioning element 19. Thus, according to Fig. 2, a prestressing element 18 is arranged between two immediately adjacent ribs 24 of the first housing wall 16, which prestressing element fixes the cooling plate 15, which is arranged in front of the respective battery cell 12 as seen in the stacking direction of the battery cells 12, in its position in the region of the first housing wall 16, namely the holding device 28 of the respective cooling plate 15, which partially engages in the groove-like profile 26 of a respective rib 24 of the first housing wall 16. In the region of the second housing wall 17, a positioning element 19 is arranged between two immediately adjacent ribs 25, which fixes the cooling plate 15, which is arranged in front of the respective battery cell 12 as seen in the stacking direction of the battery cells 12, in its position, namely the holding device 28 of this cooling plate 15, which engages in the groove-like profile 27 of the respective rib 25 of the second housing wall 17.

[0033] The preloading elements 18 therefore perform a dual function, namely, on the one hand, the preloading or bracing of the battery cells 12 in order to press them towards the opposite second housing wall 17, and, on the other hand, the fixing function for the cooling plate 15 arranged in front of the battery cell 12 in the stacking direction in the region of the first housing wall 16. The positioning elements 19 also perform a dual function, namely a stop function for the battery cells 12 and a fixing function for the cooling plates 15, specifically in the region of the second housing wall 17.

[0034] According to Fig. 2, each prestressing element 18 has a prestressing section 18a for the respective battery cell 12 to be clamped and a positioning section 18b for the respective cooling plate 15 to be fixed, wherein a cavity 18c is formed between the prestressing section 18a and the positioning section 18b.

[0035] Each prestressing element 18 and each positioning element 19 has a projection 29 or 30, respectively, which is arranged at the end of the respective battery cell 12 facing away from the stacking direction between the respective battery cell 12 and the adjacent rib 24 or 25 of the respective housing wall 16 or 17.

[0036] This prevents direct contact between the respective battery cell 12 and the respective housing wall 16, 17, namely the respective ribs 24, 25. This is particularly preferred for precise alignment and positioning of the battery cells 12 within the battery module housing 11.

[0037] Fig. 6 to 8 visualize the sequence of assembly of a battery module 10 according to the invention, wherein in Fig. 6 already the left cooling plate 15 and the Fig. 6 are arranged and fixed in the housing 11. The Fig. 6 on the right side of the battery cell 12, is already pre-fixed by its holding devices 28, the final fixing takes place in the area of ​​the housing wall 16 by means of the Fig. 6 pre-tensioning element 18 not yet brought into the final position, which in Fig. 7 is brought into the final position and arranged between two ribs 24, while fixing the Fig. 7 on the right side of the battery cell 12 shown therein arranged cooling plate 15. Subsequently, a further battery cell 12 can be arranged in the battery module housing 11, wherein the prestressing element 18 then this battery cell 12, when it is in the end position and at the in Fig. 8 right cooling plate 15, from the pre-tensioning element 18 in the direction of the Fig.8, or the positioning element 19 arranged there. In this way, cooling plates 15 and battery cells 17 can be successively arranged in stacks in the battery module housing 11. The arrangement of the positioning elements 19 on the second housing wall 17 is analogous to the arrangement of the preload elements 18 on the first housing wall 16.

Claims

[1] Battery module (10) of a traction battery of a motor vehicle, with a battery module housing (11) which has a first housing wall (16) and a second housing wall (17) opposite the first housing wall (16), with a plurality of battery cells (12) arranged in a stack in the battery module housing (11) such that a stacking direction of the battery cells (12) extends parallel to the first and second housing walls (16, 17), characterized by , that a prestressing element (18) is arranged between each battery cell (12) and the first housing wall (16), a positioning element (19) is arranged between each battery cell (12) and the second housing wall (17), at least one degassing opening (20, 21) is provided in the second housing wall (17) and in the positioning element (19) for each battery cell (12), the respective prestressing element (18) presses the respective battery cell (12) against the positioning element (19) while aligning it with the respective at least one degassing opening (20, 21) in the direction of the second housing wall (17), a cooling plate (15) is arranged on both sides of each battery cell (12) as seen in the stacking direction of the battery cells (12), the pretensioning element (18) and the positioning element (19), which is assigned to a respective battery cell (12), fixes one of the cooling plates (15) assigned to the respective battery cell (12) in its position. [2] Battery module according to claim 1, characterized by , that the first housing wall (16) is an upper housing wall in the installation position of the battery module (10) in the motor vehicle, the second housing wall (17) is a lower housing wall in the installation position of the battery module (10) in the motor vehicle. [3] Battery module according to claim 1 or 2, characterized by that the battery cells (12) are subject to expansion in the stacking direction during operation, wherein the respective prestressing element (18) presses the respective battery cell (12) perpendicular to the direction of expansion thereof in the direction of the second housing wall (17) against the positioning element (19). [4] Battery module according to one of claims 1 to 3, characterized by that the respective prestressing element (18) and the respective positioning element (19) fixes the cooling plate (15) arranged in front of the respective battery cell (12) in the stacking direction in its position. [5] Battery module according to one of claims 1 to 4, characterized by , that the first housing wall (16) and the second housing wall (17) have ribs (24, 25) on a side associated with the battery cells (12) which extend transversely to the stacking direction of the battery cells (12), the ribs (24, 25) have a groove-like profile (26, 27) on a side facing the stacking direction, holding devices (28) of the cooling plates (15) engage in the groove-like profiles (26, 27) of the ribs (24, 25), in the region of the first housing wall (16) between two immediately adjacent ribs (24) of the first housing wall (16) a prestressing element (18) is arranged, a positioning element (19) is arranged in the region of the second housing wall (17) between two immediately adjacent ribs (25) of the second housing wall (17), the holding devices (28) of each cooling plate (15) are fixed by a respective prestressing element (18) and a respective positioning element (19) in the groove-like profiles (26, 27) of the ribs (24, 25) on the first housing wall (16) and the second housing wall (17). [6] Battery module according to one of claims 1 to 5, characterized byin that each biasing element (18) and each positioning element (19) has a projection (29, 30) arranged between a respective rib (24, 25) and a respective battery cell (12). [7] Battery module according to one of claims 1 to 6, characterized by that each prestressing element (18) has a prestressing section (18a) for the respective battery cell (12) to be clamped and a positioning section (18b) for a holding device (28) of the respective cooling plate (15) to be fixed, wherein a cavity (18c) is formed between the prestressing section (18a) and the positioning section (18b). [8] Traction battery of a motor vehicle with at least one battery module according to one of claims 1 to 7.

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