Storage battery module
Through the special design of the end plate and cover plate, and by utilizing the bulge and constraint rod cutout, the problems of miniaturization and bolt tightening pressure of the battery module are solved, thereby improving battery safety and reducing weight.
Patent Information
- Application Number
- CN202422493515.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-15
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-10-15
AI Technical Summary
Existing battery modules have problems with miniaturization and bolt tightening pressure, resulting in larger dimensions in the stacked direction of individual battery cells and increased tightening pressure applied to the stacked cells.
The module employs a special design for end plates and cover plates. The end plates are configured at both ends in the stacking direction of the battery cells, and the cover plates are fixed to the end plates by bulges and constraint rods. The bulges and constraint rods reduce the bolt tightening pressure and module weight.
It effectively suppresses the dimensional increase in the stacking direction of battery cells, reduces the impact of bolt tightening pressure on the stacked cells, improves battery safety, and reduces module weight.
Smart Images
Figure CN223487180U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a battery module. Background Technology
[0002] Previously, a battery module was known, which had a single-cell stack composed of multiple battery cells (see Patent Document 1 and Patent Document 2).
[0003] Prior art patent document 1: Chinese Utility Model No. 219717144 specification
[0004] Patent Document 2: Japanese Patent No. 7387223 Utility Model Content
[0005] [The problem that the utility model aims to solve]
[0006] When housing the cell stack using a housing component, in the battery module described in Patent Document 1, since bolts are tightened in the stacking direction of the cell stacks, the tightening pressure of the bolts may exert pressure on the cell stacks. Furthermore, in the battery module described in Patent Document 2, since bolts are directly inserted into the end plate constituting the housing component and positioned at the end of the cell stack in the stacking direction to assemble the housing component, the thickness of the end plate needs to be greater than the length of the bolt shaft, thus posing a problem for miniaturization of the battery module.
[0007] The purpose of this utility model is to provide a battery module that, in order to improve battery safety, suppresses the increase in size of the battery cells in the stacking direction and suppresses the application of bolt tightening pressure to the cell stack.
[0008] [Technical means to solve the problem]
[0009] To achieve the above objectives, this utility model provides a battery module (e.g., "battery module 1" described below), comprising: a single-cell stack composed of a plurality of stacked battery cells (e.g., "battery cell 2" described below); and a housing component that internally houses the aforementioned single-cell stack; the aforementioned housing component includes: end plates (e.g., "end plates 4" described below), disposed at both ends of the aforementioned single-cell stack in the stacking direction of the aforementioned battery cells (e.g., "D1 direction" described below); and A cover plate (e.g., "cover plate 6" as described later) is disposed at both ends of the aforementioned cell stack in a direction orthogonal to the stacking direction of the aforementioned cell (e.g., "D2 direction" as described later); the fixing portion (e.g., "fixing portion 42" as described later) of the aforementioned end plate fixed to the aforementioned cover plate has a bulge portion (e.g., "bulge portion 422" as described later), which bulges out in the stacking direction of the aforementioned cell relative to the central portion (e.g., "central portion 411" as described later) of the aforementioned end plate.
[0010] In addition, preferably, the long side direction of the aforementioned end plate is aligned with the direction orthogonal to the stacking direction of the aforementioned battery cell, and multiple fixing portions are provided in the width direction relative to the long side direction of the aforementioned end plate, and an end plate cutout (e.g., "end plate cutout 43" described later) is formed between the multiple fixing portions of the aforementioned end plate.
[0011] In addition, preferably, the aforementioned battery cell has an electrode body (e.g., "electrode body 201" as described below) and a cell tab (e.g., "cell tab 202" as described below) disposed at the end of the aforementioned electrode body, and the aforementioned end plate cutout has a positional relationship that coincides with the aforementioned cell tab in the aforementioned stacking direction.
[0012] Alternatively, preferably, the aforementioned housing component includes the aforementioned end plate and binding bar (e.g., "bind bar 5" described later), the binding bar being fixed to the aforementioned cover plate and covering the aforementioned monolithic laminate, the binding bar having a binding bar cutout (e.g., "bind bar cutout 53" described later), the binding bar cutout having a shape in which the corners are cut away.
[0013] Additionally, preferably, the aforementioned constraint bar cutout has a shape that protrudes further toward the center of the long side of the end plate than the welded portion of the aforementioned constraint bar welded to the aforementioned end plate (e.g., "welded portion 52" described later).
[0014] (Effects of the utility model)
[0015] According to this utility model, a battery module can be provided, which, in order to improve battery safety, suppresses the increase in size of the battery cells in the stacking direction and suppresses the application of bolt tightening pressure to the cell stack. Attached Figure Description
[0016] Figure 1 This is a perspective view illustrating the battery module in this embodiment.
[0017] Figure 2 This is a perspective view of the battery module in this embodiment, viewed from the end plate side.
[0018] Figure 3 This is a plan view showing the bolt fastening parts of the end plate and cover plate constituting the battery module in this embodiment.
[0019] Figure 4 This is a diagram illustrating the positional relationship between the welded portion of the end plate and the constraint rod, and the cut portion of the constraint rod, which constitute the battery module in this embodiment.
[0020] Figure 5 This is an enlarged front view of the bulge of the end plate of the battery module in this embodiment.
[0021] Figure 6 It is a drawing from Figure 5 The enlarged front view shown is a diagram showing the situation after removing the end plates.
[0022] Figure 7 This is a plan view illustrating the positional relationship between the individual tabs of the battery module and the bulge of the end plate in this embodiment.
[0023] Figure Labels
[0024] 1 Battery Module
[0025] 2 battery cells
[0026] 4-end plate
[0027] 5 constraint bars
[0028] 6 cover plates
[0029] 42 Fixing part
[0030] 43 End plate cut
[0031] 52 Welding Section
[0032] 53. Constraint bar cutout
[0033] 201 electrode body
[0034] 202 single-cell electrode
[0035] 411 Central Department
[0036] 422 Drum section. Detailed Implementation
[0037] The following describes the embodiments of this utility model.
[0038] <Overall Structure of Battery Module>
[0039] The battery module 1 is mainly composed of multiple battery cells 2, a pair of end plates 4, constraint rods 5, and a cover plate 6. The end plates 4, constraint rods 5, and cover plate 6 constitute a housing component, which internally houses a stack of battery cells composed of multiple battery cells 2.
[0040] In the directions shown in the diagram, direction D1 is along the stacking direction of the multiple battery cells 2, representing the length direction of the battery module 1. Direction D2 is orthogonal to the stacking direction of the multiple battery cells 2, representing the width direction of the battery module 1. Direction D3 is orthogonal to the stacking direction of the multiple battery cells 2, representing the height direction of the battery module 1.
[0041] Battery cell 2 Figure 2 As shown, for example, an electrode body 201 is housed inside a cuboid-shaped cell case 20 made of aluminum or aluminum alloy. At the end of the electrode body 201 in the D2 direction, as... Figure 6 As shown, a single-cell tab 202 is provided throughout the entire D3 direction at this end. The upper surface of the battery cell 2 is covered by a constraint rod 5, and the battery cell stack composed of multiple battery cells 2 is covered by the constraint rod 5.
[0042] On the upper surface of the battery cell 2, a positive terminal 21 and a negative terminal 22 are protruding (see reference). Figure 7 (etc.). Among the multiple battery cells 2, the faces having the positive terminal 21 and the negative terminal 22 are arranged facing upward along the D3 direction in the figure, and a battery cell stack is formed by stacking multiple cells along the D1 direction. An insulating plate 25 is clamped between adjacent battery cells 2, 2, respectively, to achieve insulation between adjacent battery cells 2, 2.
[0043] Adjacent battery cells 2, 2 along direction D1 are oriented with alternating positive terminals 21 and negative terminals 22. The positive terminals 21 and negative terminals 22 of adjacent battery cells 2, 2 are electrically connected via a plate-shaped busbar 23. Thus, multiple stacked battery cells 2 are connected in series. In the battery cells 2, 2 respectively located at both ends, a wiring harness (not shown) is provided on the positive terminal 21 or negative terminal 22 where the busbar 3 is not provided.
[0044] End plates 4 are respectively disposed at both ends of the stacked battery cells 2 in the stacking direction (D1 direction). That is, a pair of end plates 4 are respectively disposed on the outside of the battery cells 2, 2 disposed at both ends in the stacking direction (D1 direction), clamping the multiple battery cells 2 as a whole. The detailed construction of the end plates 4 will be described below.
[0045] The constraint rods 5 are fastening components made of metal strips, respectively disposed on two sides parallel to the stacking direction (D1 direction) of the battery cells 2 (the upper and lower surfaces in the D3 direction of the battery cell stack composed of multiple battery cells 2). The two ends of the constraint rods 5 in the stacking direction (D1 direction) of the battery cells 2 are welded and fixed to the end plate 4, thereby fixing the constraint rods 5 to the cover plate 6 via the end plate 4.
[0046] The constraint rod 5, located near the two end edges of the battery cell 2 in the stacking direction (D1 direction), connects the welded portion 52 (see reference) along these two end edges. Figure 2 , Figure 4 The cells 2 are respectively fused to the ends of the end plate 4 in the width direction (D3 direction) and fixed relative to the end plate 4. As a result, the multiple battery cells 2 are given a constraint force in the stacking direction (D1 direction), thereby suppressing the expansion caused by the charging and discharging of the battery cells 2.
[0047] The cover plate 6 is disposed at both ends of the cell stack in a direction orthogonal to the stacking direction of the battery cell 2 (D2 direction). The cover plate 6 is formed into a rectangular shape that covers the entire surface of the cell stack of the battery cell 2 in the D2 direction. The four corners of the cover plate 6 are fixed to the end plate 4 by bolts 63.
[0048] <Endplate 4>
[0049] like Figures 1 to 5 As shown, the end plate 4 has a central plate-shaped portion 41 and a fixing portion 42. The central plate-shaped portion 41 has a rectangular plate shape and is located in the center of the end plate 4. The long side direction of the central plate-shaped portion 41 is consistent with the long side direction of the end plate 4 and is consistent with the direction orthogonal to the stacking direction of the battery cell 2 (D2 direction).
[0050] The fixing portions 42 are provided from the four corners of the central plate-shaped portion 41, protruding towards the long side of the central plate-shaped portion 41 and away from the central plate-shaped portion 41. In other words, there are four fixing portions 42, two in each direction in the width direction (D3 direction) relative to the long side direction (D2 direction) of the end plate 4. The fixing portions 42 have plate-shaped portion extensions 421 and bulges 422. The plate-shaped portion extensions 421 are composed of a portion with the same thickness as the central plate-shaped portion 41 that protrudes away from the central plate-shaped portion 41.
[0051] The bulge 422 is integrally formed with the plate-shaped extension 421. It extends from the protruding end of the central plate-shaped portion 41 toward the central plate-shaped portion 41 to a predetermined position and is composed of a portion that bulges out further toward the stacking direction (D1 direction) of the battery cell 2 than the inner surface 412 of the central plate-shaped portion 41.
[0052] The fixing portion 42, which is composed of the plate-shaped extension 421 and the bulge 422, is thicker in the stacking direction (D1 direction) of the battery cell 2 compared to the central plate-shaped portion 41. As a result, a screw hole is formed at the protruding end of the fixing portion 42 (the end in the direction orthogonal to the stacking direction of the battery cell 2 (D2 direction)) extending in the D2 direction and towards the central portion 411 of the central plate-shaped portion 41, for the bolt 63 to be screwed in.
[0053] The fixing portions 42 are provided from the four corners of the central plate-shaped portion 41, in the direction of the long side of the central plate-shaped portion 41 and away from the central plate-shaped portion 41. Therefore, the space between the pair of fixing portions 42, which is surrounded by the C-shaped portion formed by the end edge of the central plate-shaped portion 41 in the long side direction (D2 direction) of the end plate 4 and the pair of fixing portions 42 in the width direction (D3 direction) of the end plate 4, constitutes an end plate cutout portion 43 that is recessed toward the central portion 411 of the central plate-shaped portion 41.
[0054] like Figure 5 As shown, in the stacking view (D1 direction view) of the battery cell 2, the end plate cutout 43 is positioned to coincide with the cell tab 202. Specifically, the end plate cutout 43 is positioned near... Figure 5 The central portion 411 ( Figure 5 The portion on the right side of the end plate cutout 43 shown has a portion opposite to the end of the single electrode tab 202 in the D2 direction, i.e., the portion connected to the electrode body 201. Figure 5 The positional relationship of the overlapping of the left side portion of the single cell tab 202 in the battery cell 2. Therefore, in the stacked direction view (D1 direction view) of the battery cell 2, the single cell tab 202 and the insulating plate 25 can be visually confirmed by means of the end plate cutout 43.
[0055] <Cover plate 6>
[0056] Cover plate 6 Figures 2-4 As shown, it has a rectangular plate-shaped cover body 61, an end flange 62 integrally provided at the end of the long side of the cover body 6, and fixing portions 621 protruding from both ends of the end flange 62 in the D3 direction.
[0057] The long side of the cover body 61 is aligned with the stacking direction (D1 direction) of the battery cell 2. The end flange 62 extends from one end to the other in the D3 direction at the end of the cover body 61 in the D1 direction, forming a flat plate orthogonal to the D1 direction. The fixing part 621 is integrally provided at both ends of the end flange 62 in the D3 direction, in other words, integrally provided at the four corners of the cover body 61, and has a flat plate orthogonal to the D2 direction.
[0058] The fixing part 621 is configured to overlap the end of the fixing part 42 of the end plate 4 in a direction orthogonal to the stacking direction of the battery cell 2 (D2 direction). A through hole is formed in the fixing part 621 in the D2 direction. By forming the fixing part 621 to overlap the end of the fixing part 42 of the end plate 4 in the D2 direction, and by having a bolt 63 pass through the through hole of the fixing part 621 and screw into the screw hole of the fixing part 42 of the end plate 4, the fixing part 621 is fixed to the plate-shaped extension 421 and the protruding part 422 of the fixing part 42 with the axis of the bolt 63 pointing in the D2 direction. Thus, the cover plate 6 is fixed to the end plate 4.
[0059] <Constraint Rod 5>
[0060] The constraint rod 5 has a rectangular shape that completely covers the two sides (the upper and lower surfaces in the D3 direction of the battery cell stack composed of multiple battery cells 2) parallel to the stacking direction (D1 direction) of the battery cell 2. The portions corresponding to the four corners relative to the central portion 51 of the rectangular constraint rod 5 are as follows: Figure 2 As shown, a constraint rod cutout 53 is formed.
[0061] The constraint rod cutout 53 is formed by cutting away the four corners of the rectangular constraint rod 5. Specifically, as shown in the figure... Figure 2 , Figure 4 As shown, it has a C-shaped opening in a direction orthogonal to the stacking direction of the battery cell 2 (D2 direction) and away from the central portion 51 of the constraint rod 5.
[0062] The constraint rod cutout 53 has a shape that protrudes further toward the center of the long side of the end plate 4 than the welded portion 52 of the constraint rod 5 welded to the end plate 4.
[0063] Specifically, the constraint bar cutout 53, as previously described, has a C-shape, therefore... Figure 2 , Figure 4 As shown, the central portion 531 of the constraint rod cutout 53 in the stacking direction (D1 direction) of the battery cell 2 is most perpendicular to the stacking direction of the battery cell 2 in the direction (D2 direction). Figure 2 , Figure 4The rightward protrusion is also present. Similarly, the central portion 532 of the constraint rod cutout 53 in the direction orthogonal to the stacking direction of the battery cell 2 (D2 direction) is closest to the stacking direction of the battery cell 2 (D1 direction). Figure 2 , Figure 4 (The upward direction) protrudes.
[0064] Therefore, the central portion 531 is located at the end 521 of the welding portion 52 of the constraint rod 5 in a direction orthogonal to the stacking direction of the battery cell 2 (D2 direction). Figure 2 , Figure 4 The left end of the welded part 52 in the middle, further towards Figure 2 , Figure 4 The right-hand direction (D2 direction) of the end plate 4, the central part 411, and the central part 51 of the constraint rod 5 protrude.
[0065] The effects of the above implementation method are as follows.
[0066] In this embodiment, the fixing part 42 of the end plate 4 fixed to the cover plate 6 has a bulge 422, which bulges out toward the stacking direction of the battery cell 2 relative to the central part 411 of the end plate 4.
[0067] Therefore, the cover plate 6 can be fixed to the end plate 4 by partially engaging the fixing part 42 with the protruding part 422 and the bolt 63. Thus, the cover plate 6 can be fastened to the end plate 4 while suppressing the overall thickness of the end plate 4, thereby suppressing the increase in size of the battery cell 2 in the stacking direction.
[0068] Furthermore, by bulging the 422 in the stacking direction (D1 direction) of the battery cell 2, the cover plate 6 can be fastened to the end plate 4 by bolts 63 whose axes point in a direction orthogonal to the stacking direction of the battery cell 2 (D2 direction). Therefore, compared to the case where the cover plate is fastened to the end plate by bolts whose axes point in the stacking direction (D1 direction) of the battery cell, the pressure generated by the tightening of the bolts 63 during this tightening can be suppressed from acting on the battery cell stack composed of battery cells 2 in the stacking direction (D1 direction).
[0069] Furthermore, in this embodiment, the long side direction of the end plate 4 is aligned with the direction orthogonal to the stacking direction of the battery cell 2 (D2 direction), and multiple fixing portions 42 are provided in the width direction (D3 direction) relative to the long side direction of the end plate 4. An end plate cutout 43 is formed between the multiple fixing portions 42 of the end plate 4. As a result, the weight of the battery module 1 can be reduced by reducing the weight of the end plate 4 in areas other than the multiple fixing portions 42.
[0070] Furthermore, in this embodiment, the battery cell 2 has an electrode body 201 and a cell tab 202 disposed at the end of the electrode body 201. The end plate cutout 43 is positioned to overlap with the cell tab 202 in the stacking direction (D1 direction) of the battery cell 2. Thus, by forming the end plate 4 to a shape that overlaps with the cell tab 202 in the stacking direction (D1 direction) of the battery cell 2 while protecting the electrode body 201 from the outside, the weight of the end plate 4 can be reduced as much as possible.
[0071] In this embodiment, the housing component includes an end plate 4 and a constraint rod 5. The constraint rod 5 is fixed to the cover plate 6 and covers the battery cell stack. The constraint rod 5 has a constraint rod cutout 53, which has a shape in which the corner is cut out. Thus, it can be configured such that the tension of the battery cell stack expanding in the stacking direction (D1 direction) of the battery cell 2 is concentrated on the periphery of the constraint rod cutout 53, and a structure can be formed in which the end portion of the constraint rod 5 fixed to the cover plate 6 is not easily peeled off from the cover plate 6.
[0072] Furthermore, in this embodiment, the constraint rod cutout portion 53 has a shape that protrudes further toward the center of the long side of the end plate 4 than the weld portion 52 of the aforementioned constraint rod 5 welded to the end plate 4. Thus, it becomes a shape in which a portion of the central portion 531 of the constraint rod cutout portion 53 is cut away from any part of the weld portion 52, specifically the end portion 521 of the weld portion 52, toward the center portion 411 of the end plate 4 and the center portion 51 of the constraint rod 5. This allows the tension that would cause the battery cell stack to expand in the stacking direction (D1 direction) of the battery cell 2 to be concentrated at the end portion 52.
[0073] Furthermore, this utility model is not limited to the above-described embodiments. Modifications and improvements within the scope of achieving the purpose of this utility model are included in this utility model.
[0074] For example, there may be two fixing parts 42 in each of the D3 directions, totaling four, but this is not a limitation; there may be multiple fixing parts. In addition, the structure and shape of the bulge, end plate cutout, and constraint rod cutout are not limited to the structure and shape of the bulge 422, end plate cutout 43, and constraint rod cutout 53 in this embodiment.
Claims
1. A battery module, characterized in that, have: A single-cell stack, composed of multiple stacked battery cells; and, The housing component internally houses the aforementioned monolithic laminate; The aforementioned housing component includes: End plates are disposed at both ends of the aforementioned cell stack in the stacking direction of the aforementioned battery cells; and, A cover plate is disposed at both ends of the aforementioned cell stack in a direction orthogonal to the stacking direction of the aforementioned cell; The fixing portion of the end plate fixed to the aforementioned cover plate has a bulge portion, which bulges out toward the stacking direction of the aforementioned battery cells relative to the central portion of the aforementioned end plate.
2. The battery module according to claim 1, wherein, The long side of the aforementioned end plate is aligned with a direction orthogonal to the stacking direction of the aforementioned battery cells. The aforementioned fixing part has multiple parts in the width direction relative to the long side direction of the aforementioned end plate. An end plate cutout is formed between the aforementioned fixing portions of the end plate.
3. The battery module according to claim 2, wherein, The aforementioned battery cell has an electrode body and a cell tab disposed at the end of the aforementioned electrode body. The aforementioned end plate cutout has a positional relationship with the aforementioned monomer tab in the aforementioned stacking direction.
4. The battery module according to claim 1, wherein, The aforementioned housing component includes the aforementioned end plate and constraint rod, the constraint rod being fixed to the aforementioned cover plate and covering the aforementioned monolithic laminate. The aforementioned constraint rod has a constraint rod cutout portion, which has a shape in which the corners are cut away.
5. The battery module according to claim 4, wherein, The aforementioned constraint rod cutout has a shape that protrudes further toward the center of the long side of the end plate than the welded portion of the aforementioned constraint rod welded to the aforementioned end plate.