A module end plate structure for inhibiting cell bulging

Abstract

The utility model discloses a kind of module end plate structures of inhibiting battery bulge, for fixing battery, including two module end plates, two module end plates are clamped in the thickness of battery two sides;Module end plate includes outer end plate face and inner end plate face, outer end plate face is straight face plane, for receiving and transmitting external constraint force;Inner end plate face is provided with the convex structure of close contact on the surface of battery, for inhibiting the bulge deformation of battery;The top of convex structure is also provided with a layer of flexible layer, and flexible layer is used to increase contact area.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a module end plate structure for suppressing cell bulging. Background Technology

[0002] Lithium batteries are prone to swelling or bulging under long-term cyclic use or abnormal operating conditions (such as overcharging, over-discharging, and high-temperature environments). Battery bulging not only reduces structural space and affects the compact design of equipment, but also leads to battery performance degradation and may even cause internal short circuits, thermal runaway, and other safety issues, threatening the overall safety of the system. Existing technologies for suppressing battery bulging mainly suffer from the following problems: 1. These methods mainly focus on optimizing the internal materials and management systems of batteries. However, these methods are complex, costly, and difficult to apply to batteries that have already been manufactured. 2. The existing CN120021080A, which uses mechanical restraint, relies on passive deformation after being subjected to force to increase the contact area. Its suppression of bulging is delayed, and the uniformity of pressure distribution is limited by the material's deformation capacity, making it difficult to achieve active and precise suppression of bulging in the center of the cell.

[0003] Therefore, it is necessary to provide a module end plate structure that suppresses cell bulging, so as to solve the problem of battery bulging and expansion without changing the internal design of the battery or significantly increasing the weight and volume of the battery module. Utility Model Content

[0004] In view of this, the present invention aims to propose a module end plate structure for suppressing cell bulging, so as to solve the problems of high cost and complex process caused by the reliance on the optimization of internal battery materials in the prior art; as well as the problems of suppression lag and uneven pressure distribution caused by the passive deformation of the mechanical constraint structure.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A module end plate structure for suppressing cell bulging, used to fix a cell 1, includes two module end plates 2, which are sandwiched on both sides of the thickness of the cell 1; each module end plate 2 includes an outer end plate surface 21 and an inner end plate surface 22, the outer end plate surface 21 is a flat plane for receiving and transmitting external constraint forces; the inner end plate surface 22 is provided with a protruding structure that closely contacts the surface of the cell 1 for suppressing the bulging deformation of the cell 1; a flexible layer is also provided on the top of the protruding structure to increase the contact area with the cell 1.

[0006] Compared with the prior art, the beneficial effects of this utility model are: the module end plate structure of this utility model can actively mechanically suppress the bulging area of ​​the battery cell by setting a protruding structure on the inner end plate surface and making close contact with the surface of the battery cell; at the same time, the flexible layer set on the top of the protruding structure can adaptively deform under the action of prestress, effectively increasing the contact area, avoiding stress concentration, achieving uniform distribution of interface pressure, and simultaneously improving the heat dissipation performance of the battery cell.

[0007] As a preferred technical solution: As described above, in a module end plate structure for suppressing cell bulging, the protrusion structure is an arc-shaped protrusion whose highest point abuts against the middle of the cell end face; this curved surface can provide precise centering suppression force in the early stage of bulging, effectively preventing the bulging from expanding further.

[0008] As described above, the module end plate structure for suppressing cell bulging includes multiple arc-shaped protrusions that simultaneously abut against the end face of the cell. This curved surface forms a wave-like contact interface, which can adapt to the different bulges in different areas of the cell surface, achieving a more comprehensive pressure distribution and suppression effect.

[0009] As described above, a module end plate structure for suppressing cell bulging includes an arc-shaped protrusion abutting the middle of the cell end face, and multiple arc-shaped protrusions simultaneously abutting the cell end face; through the synergistic effect of central dominant suppression and peripheral adaptive compensation, efficient suppression and pressure balance of the cell's full-area bulging morphology are achieved.

[0010] As described above, a module end plate structure for suppressing cell bulging is provided, wherein the module end plate 2 is hollow inside, and a reinforcing rib 23 for enhancing structural rigidity is provided in the hollow cavity of the module end plate 2; the reinforcing rib 23 is supported between the outer end plate surface 21 and the inner end plate surface 22; the provision of the reinforcing rib significantly reduces the self-weight of the end plate while ensuring the end plate's resistance to deformation, thus optimizing the overall weight distribution of the module.

[0011] As described above, in a module end plate structure for suppressing cell bulging, the reinforcing rib 23 is in the shape of a ring and is arranged around the inner circumferential wall of the end plate to form a uniform stress transmission path, effectively improving the circumferential stiffness and structural stability of the end plate under compressive load.

[0012] As described above, a module end plate structure for suppressing cell bulging has a limiting groove 24 on the outer end plate surface 21 of the module end plate 2; at least one strapping 25 is fixed on the limiting groove 24, and the strapping 25 is used to fix and press multiple cells 1 and the module end plate 2 together; by setting a limiting groove on the module end plate structure and setting a strapping 25 on the limiting groove to tighten the module end plate and the cells, it can be ensured that the prestress is applied uniformly and stably to the cell stack.

[0013] The above technical solution is only one feasible technical solution of this utility model. The protection scope of this utility model is not limited to this. Those skilled in the art can reasonably adjust the specific design according to actual needs. Attached Figure Description

[0014] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein: Figure 1 This is a schematic diagram of the module end plate structure for suppressing cell bulging in this utility model; Figure 2A This is a schematic cross-sectional view of a curved surface of a pool in this utility model; Figure 2B This is a schematic cross-sectional view of multiple continuous curved surfaces of the pool in this utility model; Figure 2C This is a schematic cross-sectional view of the combined anti-pool surface curved surface in this utility model; Figure 3 This is a schematic cross-sectional view of the curved surface of the pool abutment with circular reinforcing ribs in this utility model; Figure 4 This is a schematic diagram of the module end plate structure with limiting grooves and strapping in this utility model.

[0015] Explanation of reference numerals in the attached diagram: 1. Battery cell; 2. Module end plate; 21. Outer end plate surface; 22. Inner end plate surface; 23. Reinforcing rib; 24. Limiting groove; 25. Bundling strap. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] like Figures 1-4 As shown, this utility model provides a module end plate structure for suppressing cell bulging, used to fix the cell 1, including two module end plates 2, which are clamped on both sides of the thickness of the cell 1.

[0018] The module end plate 2 includes an outer end plate surface 21 and an inner end plate surface 22. The outer end plate surface 21 is a flat surface used to receive and transmit external constraint forces. The inner end plate surface 22 is provided with a protruding structure that is in close contact with the surface of the cell 1 to suppress the bulging deformation of the cell 1.

[0019] The top of the raised structure is also provided with a flexible layer. The flexible layer is an elastic dielectric layer used to increase the contact area with the battery cell 1. For example, the flexible layer can be thermally conductive silicone, thermally conductive foam or phase change thermally conductive material. By deforming itself, it increases the contact area with the surface of the battery cell 1, so as to achieve uniform pressure distribution and improve heat dissipation efficiency.

[0020] Optionally, the flexible layer can be fixed to the surface of the raised structure by adhesive bonding or in-mold molding.

[0021] In this embodiment, cell 1 is a square aluminum-cased cell. When cell 1 begins to expand, the protruding structure on the inner end plate surface 22 of the module end plate 2 will contact it and apply pressure, which can actively mechanically suppress the bulging area of ​​the cell. At the same time, the flexible layer set on the top of the protruding structure can adaptively deform under prestress due to its own material properties, effectively increasing the contact area with the surface of cell 1, avoiding stress concentration, and achieving uniform distribution of interface pressure. Compared with traditional methods of suppressing battery bulging, this structure is simple and reliable, and can effectively suppress battery bulging without changing the internal design of the battery.

[0022] In order to more effectively improve the suppression of cell bulging and optimize stress distribution, the protrusion structure is further defined.

[0023] like Figure 2A As shown, the protruding structure is an arc-shaped protrusion with its highest point abutting against the middle of the end face of the cell. The surface is a smooth arch with a high middle and low ends. Its highest point is in close contact with the center of cell 1. Since the bulging deformation of cell 1 usually starts in the central area, this structure can provide precise centering suppression force in the early stage of bulging. The arched surface disperses the concentrated stress to the surrounding areas, effectively suppressing the further development of bulging.

[0024] like Figure 2B As shown, the protruding structure consists of multiple arc-shaped protrusions that simultaneously abut against the end face of the battery cell. Since the bulge of battery cell 1 also exhibits non-uniform or banded distribution characteristics, this curved surface forms a wave shape that is in close contact with battery cell 1. It can achieve precise matching and suppression of local bulges through the multi-peak structure, uniformly transmit expansion stress along the wave direction, and avoid local stress concentration.

[0025] like Figure 2C As shown, the protrusion structure includes an arc-shaped protrusion that abuts against the middle of the cell end face, and multiple arc-shaped protrusions that abut against the cell end face simultaneously, forming a hierarchical suppression structure. It can suppress the core bulge area by the central arc surface, and at the same time use the peripheral curved surface to adaptively compensate for the edge and local bulges, so as to achieve dynamic balance and optimized distribution of stress in the whole area.

[0026] In this embodiment, the height, radius of curvature, and tilt angle of the abutment surface can be designed according to the specific dimensions of the battery cell and the expected expansion amount. For example, the height of the abutment surface can be set to 1% to 5% of the battery cell thickness; the radius of curvature can be designed to be 200mm to 1000mm to form a smooth force transition; the tilt angles on both sides of the abutment surface can be 5 degrees to 15 degrees to ensure that the pressure can diffuse smoothly to the edge area of ​​the end plate. Specific setting parameters are not limited here.

[0027] To enhance the end plate's resistance to deformation and reduce the overall weight of the battery module, the module end plate 2 is further defined.

[0028] like Figure 3 As shown, the module end plate 2 is hollow inside, and a reinforcing rib 23 for enhancing structural rigidity is provided in the hollow cavity of the module end plate 2; the reinforcing rib 23 is supported between the outer end plate surface 21 and the inner end plate surface 22.

[0029] In this embodiment, the reinforcing rib 23 is fixedly connected to the inner walls of the outer end plate 21 and the inner end plate 22 at its two ends to form a support structure, so that the external load can be effectively transmitted between the two end plate surfaces through the reinforcing rib 23.

[0030] Optionally, the reinforcing rib 23 can be co-cured and formed with the inner wall of the outer end plate 21 and the inner end plate 22 during casting; or it can be fixedly connected by welding or bonding.

[0031] Optionally, the reinforcing rib 23 can be made of a metallic material, such as aluminum alloy or high-strength steel, to provide excellent support strength.

[0032] Furthermore, the reinforcing rib 23 is in the shape of a ring and is arranged around the inner peripheral wall of the module end plate 2 to form a closed ring support frame.

[0033] In this embodiment, the outline of the annular reinforcing rib 23 adopts a smoothly transitioning arc design, and its force path is transmitted along the annular curved surface, forming an optimized force flow transmission channel. This avoids stress directly penetrating the module end plate 2 through a vertical path, but instead converts the load into circumferential stress through the curved surface of the annular rib, effectively eliminating stress concentration points, reducing the weight of the module end plate, and significantly improving the structural durability of the module end plate.

[0034] Furthermore, a limiting groove 24 is provided on the outer end plate surface 21 of the module end plate 2; at least one strapping 3 is fixed on the limiting groove 24, and the strapping 3 is used to fix and press multiple battery cells 1 and the module end plate 2 together.

[0035] In this embodiment, each of the two module end plates 2 is provided with two limiting grooves 24, and a strapping strap 3 is fixed on each limiting groove 24. The strapping strap 3 wraps around the battery cell 1 and the two module end plates 2 at both ends, and its two ends are fixedly connected by special buckles or welding. Radial prestress is applied by a tensioning tool, so that the annular tension generated by the strapping strap 3 is converted into an axial clamping force on the module end plate 2, thereby firmly pressing the battery cell 1 and the module end plate 2 into one, and further firmly combining the battery cell 1 and the module end plate 2 into an integral rigid structure, realizing the coordinated force and long-term stable constraint among multiple components.

[0036] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent changes made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A module end plate structure for suppressing cell bulging, used to fix the cell (1), characterized in that, It includes two module end plates (2), which are sandwiched on both sides of the thickness of the cell (1); The module end plate (2) includes an outer end plate surface (21) and an inner end plate surface (22). The outer end plate surface (21) is a straight plane, used to receive and transmit external constraint forces. The inner end plate surface (22) is provided with a protruding structure that is in close contact with the surface of the cell (1), used to suppress the bulging deformation of the cell (1). The top of the protruding structure is also provided with a flexible layer, which is used to increase the contact area between the protruding structure and the battery cell (1).

2. The module end plate structure for suppressing cell bulging according to claim 1, characterized in that, The protrusion structure is an arc-shaped protrusion whose highest point rests against the middle of the end face of the battery cell.

3. The module end plate structure for suppressing cell bulging according to claim 1, characterized in that, The protrusion structure consists of multiple arc-shaped protrusions that simultaneously abut against the end face of the battery cell.

4. The module end plate structure for suppressing cell bulging according to claim 1, characterized in that, The protrusion structure includes an arc-shaped protrusion that abuts against the middle of the end face of the battery cell, and multiple arc-shaped protrusions that abut against the end face of the battery cell simultaneously.

5. The module end plate structure for suppressing cell bulging according to claim 1, characterized in that, The module end plate (2) is hollow inside, and a reinforcing rib (23) for enhancing structural rigidity is provided in the hollow cavity of the module end plate (2); the reinforcing rib (23) is supported between the outer end plate surface (21) and the inner end plate surface (22).

6. The module end plate structure for suppressing cell bulging according to claim 5, characterized in that, The reinforcing rib (23) is in the shape of a ring.

7. The module end plate structure for suppressing cell bulging according to claim 1, characterized in that, The outer end plate (21) of the module end plate (2) is provided with a limiting groove (24); at least one strapping (25) is fixed on the limiting groove (24), and the strapping (25) is used to fix and press together multiple battery cells (1) and the module end plate (2).

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