End plate and battery pack

Abstract

The utility model provides an end plate and a battery pack, the end plate comprises a plate main body, a boss arranged on the plate main body, and a bolt mounting hole arranged on the boss, the boss extends along the height direction of the plate main body, the bolt mounting hole penetrates through the boss along the height direction of the plate main body, and the top of the plate main body is provided with a groove connected with the top of the boss. The groove comprises a first side wall close to the middle position of the plate body in the length direction, a second side wall away from the middle position of the plate body in the length direction and a third side wall connected between the first side wall and the second side wall, and a reinforcing structure is at least arranged between the first side wall and the third side wall. According to the end plate, the cracking phenomenon of a traditional module end plate can be solved in a targeted mode, and the self-lightweight design of the end plate can be achieved while the bearing requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to an end plate. Meanwhile, the utility model also relates to a battery pack provided with the end plate. Background Art

[0002] The battery cells of the battery pack will expand during their service life due to the mechanism of the battery cells. As the end of the life cycle approaches, this expansion becomes more obvious. Therefore, during the product design phase, it is necessary to consider the impact of the battery cell expansion on the product structure and ensure that its strength does not fail during the service life cycle. Usually, the expansion force of the battery pack module will be transmitted to the end plate at the end. The structural strength of the end plate needs to be sufficient to prevent failure after the battery cell expands.

[0003] Moreover, with the advancement of the lightweight trend in the automotive industry, more and more battery pack module end plates are being made of materials that have been changed from traditional cast aluminum and aluminum profiles to injection molded parts such as PA66 (Polyamide 66; polyhexamethylene adipamide), thereby reducing the mass of the entire module and increasing the energy density of the battery pack. However, compared with cast aluminum and aluminum profiles, injection molded parts have disadvantages such as low structural strength and poor ductility, so end plate cracking often occurs in the market. Utility Model Content

[0004] In view of this, the utility model aims to provide an end plate, which can improve the cracking situation.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] An end plate comprises a plate body, a boss arranged on the plate body, and a bolt mounting hole arranged on the boss; the boss is arranged to extend along the height direction of the plate body, the bolt mounting hole passes through the boss along the height direction of the plate body, and the top of the plate body is provided with a groove connected to the top of the boss;

[0007] The groove includes a first side wall close to the middle position of the length direction of the plate body, a second side wall away from the middle position of the length direction of the plate body, and a third side wall connected between the first side wall and the second side wall, and a reinforcement structure is provided between at least the first side wall and the third side wall.

[0008] Furthermore, the reinforcement structure includes a reinforcement rib connected between the first side wall and the third side wall, and the bottom of the reinforcement rib is connected to the top of the boss.

[0009] Furthermore, along the height direction of the plate body, looking from top to bottom, the reinforcing ribs are in an arc shape and / or a straight line shape.

[0010] Furthermore, the thickness dimension t of the reinforcing rib is between 2.5 and 3.5 mm.

[0011] Furthermore, when viewed from top to bottom, the reinforcing rib is in an arc shape, the reinforcing rib takes the center O of the bolt mounting hole as the center, and the radius R of the reinforcing rib taking the bolt mounting hole as the center is between 50 and 120 mm.

[0012] Furthermore, when viewed from top to bottom, the reinforcing rib is in a straight line, the angle between the reinforcing rib and the first side wall is between 30 and 60°, or the angle between the reinforcing rib and the third side wall is between 30 and 60°.

[0013] Furthermore, in the height direction of the plate body, the top of the reinforcing rib is not higher than the top of the plate body.

[0014] Furthermore, a reinforcing rib is provided between the boss and the plate body.

[0015] Furthermore, the end plate is formed by integral injection molding.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] The end plate described in the utility model can improve the structural strength by setting a reinforcing structure between the first side wall and the third side wall, and effectively avoid stress concentration caused by alternating torsional deformation and structural mutation at the bolt mounting hole position of the end plate, which may lead to fatigue failure of the end plate and cracking, thereby helping to improve the safety of the battery pack.

[0018] Secondly, the bottom of the reinforcing rib is connected to the top of the boss, which is conducive to improving the rigidity of the end plate at the bolt mounting hole position, thereby improving the overall rigidity of the end plate. Setting the reinforcing rib to an arc shape or a straight line shape can improve the top thrust of the end plate during the expansion of the battery cell and the torsional deformation of the bolt mounting hole position of the end plate. The thickness of the reinforcing rib is set between 2.5mm and 3.5mm to reduce the risk of end plate cracking caused by torsional deformation at the bolt mounting hole position caused by the expansion of the battery cell, thereby enhancing the rigidity and strength of the end plate. Setting the radius R of the reinforcing rib with the bolt mounting hole as the center to between 50 and 120mm is conducive to saving space so as not to affect the assembly of the bolts during the installation process, thereby ensuring the quality of the bolt connection, improving the rigidity of the bolt mounting hole position, and reducing the risk of cracking at the bolt mounting hole position due to alternating torsional deformation.

[0019] Furthermore, the angles between the reinforcing ribs and the first side wall and the second side wall are set to 30-60°. This setting can reduce the risk of cracking of the end plate caused by alternating torsional deformation of the bolt mounting hole position due to the cyclic expansion of the battery cell, and can also save space. The top of the reinforcing rib is lower than the top of the plate body. This setting can not only avoid the damage to the ribs caused by the excessive height of the reinforcing ribs, thereby reducing the rigidity of the product, but also save the Z-direction space of the battery pack. In addition, reinforcing ribs are provided between the boss and the plate body to better restrain the expansion force generated by the expansion of the battery cell. The end plate is made of one-piece injection molding, which is conducive to improving lightweight design.

[0020] In addition, another object of the present invention is to provide a battery pack, in which the end plate as described above is provided.

[0021] The battery pack described in the present invention and the above-mentioned end plate have the same beneficial effects as those of the conventional technology, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0023] Figure 1 This is a schematic diagram of the overall structure of an end plate provided with linear reinforcing ribs according to an embodiment of the utility model;

[0024] Figure 2 This is a schematic diagram of the overall structure of the end plate provided with arc-shaped reinforcing ribs according to an embodiment of the utility model;

[0025] Figure 3 This is a schematic diagram of the structure of the end plate abutting against one side of the battery module according to an embodiment of the utility model;

[0026] Figure 4 for Figure 1 A top view of

[0027] Figure 5 for Figure 4 The enlarged view of point A in the middle;

[0028] Figure 6 for Figure 4 The enlarged view of point B in the middle;

[0029] Figure 7 for Figure 2 A top view of

[0030] Figure 8 for Figure 7 Enlarged view of point C in the middle;

[0031] Description of reference numerals:

[0032] 1. Plate body; 11. Boss; 111. Bolt mounting hole; 12. Groove; 121. First side wall; 122. Second side wall; 123. Third side wall; 13. Strengthening structure; 131. Strengthening rib; 14. Strengthening rib; 141. Transverse rib; 142. Longitudinal rib;

[0033] 2. Lower housing; 3. Cell module; 4. Filler; 5. Plane;

[0034] O, center of circle; R, radius of arc-shaped reinforcing rib; t, thickness of reinforcing rib; C1, angle between reinforcing rib and third side wall; C2, angle between reinforcing rib and first side wall. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0036] In the description of the present invention, it should be noted that if there are terms such as "upper", "lower", "inner", "outer" and the like indicating orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first" and "second", they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0037] Taking the battery pack where the end plate described in the present invention is located as an example, the directional words used in the embodiments, such as "up, down, left, right, front, and back", are based on Figure 1 The up-down direction (also called height direction, or whole package Z direction), left-right direction (also called width direction, or whole package Y direction) and front-back direction (also called length direction, or whole package X direction) in the shown state are defined as references.

[0038] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installation", "connection", "connection" and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0039] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0040] Embodiment 1

[0041] This embodiment relates to an end plate, the overall structure of which is as follows: Figure 1 and Figure 2 As shown, the end plate of this embodiment includes a plate body 1, a boss 11 arranged on the plate body 1, and a bolt mounting hole 111 arranged on the boss 11, and the boss 11 is extended along the height direction of the plate body 1, the bolt mounting hole 111 passes through the boss 11 along the height direction of the plate body 1, and the top of the plate body 1 is provided with a groove 12 connected to the top of the boss 11.

[0042] At the same time, the groove 12 includes a first side wall 121 close to the middle position of the length direction of the plate body 1, a second side wall 122 away from the middle position of the length direction of the plate body 1, and a third side wall 123 connected between the first side wall 121 and the second side wall 122, and a reinforcing structure 13 is provided at least between the first side wall 121 and the third side wall 123.

[0043] It should be noted that the relevant structural parts not mentioned in this embodiment can refer to the various structures of the battery pack in the prior art, such as the lower shell 2 for installing the end plate, the battery module 3 composed of multiple battery cells, the plane 5 in contact with the battery module and the filling member 4 arranged between the battery cells.

[0044] In specific implementation, one side of the plate body 1 is used to abut and fix the battery cell module 3, and the boss 11 is arranged on the other side of the plate body 1. The end plate is usually connected to the lower shell 2 by bolts passing through the bolt mounting holes 11, and torque is applied to the bolts, that is, the end plate will first be subjected to the axial compressive stress from the bolts.

[0045] After the battery cells expand, the expanded battery cells will first consume the gaps between the battery cells because the expansion force is the largest in the middle of the width direction of the end plate. Then, as the expansion force gradually increases, the force will be continuously applied to the end plate, causing the end plate to deform.

[0046] At the same time, the battery cell is usually accompanied by charge and discharge cycles, and the end plate needs to withstand periodic cyclic loads, and the end plate is restricted on the lower shell 2 by bolts, so the end plate is prone to alternating torsional deformation at the position of the bolt mounting hole 111, causing fatigue failure of the end plate.

[0047] It can be understood that the groove 12 is composed of a first side wall 121, a second side wall 122 and a third side wall 123, and by arranging a reinforcing structure 13 between the first side wall 121 and the third side wall 123, the structural strength can be improved, and the stress concentration caused by the alternating torsional deformation and structural mutation at the position of the bolt mounting hole 111 of the end plate can be effectively avoided, thereby preventing fatigue failure of the end plate structure and reducing the risk of cracking.

[0048] Furthermore, by providing the groove 12, the influence of the end plate on the product structure when the battery cell expands is improved, and its strength is ensured not to fail during the service life cycle, and the structure is simple and easy to arrange and install.

[0049] Based on the above overall introduction, in this embodiment, as a preferred implementation form, Figure 1 and Figure 2 As shown, the reinforcement structure 13 includes a reinforcement rib 131 connected between the first side wall 121 and the third side wall 123 , and the bottom of the reinforcement rib 131 is connected to the top of the boss 11 .

[0050] By providing the reinforcing rib 131, the structural strength failure of the end plate can be effectively avoided. At the same time, the bottom of the reinforcing rib 131 is connected to the top of the boss 11, which is beneficial to improve the rigidity of the end plate at the bolt mounting hole position, thereby improving the overall rigidity of the end plate.

[0051] Here, in this embodiment, as a preferred implementation form, Figure 4 and Figure 7 As shown, along the height direction of the plate body 1, looking from top to bottom, the reinforcing rib 131 is in an arc shape or a straight line shape. This arrangement can improve the thrust force on the end plate during the expansion of the battery cell and the torsional deformation of the bolt mounting hole 11 of the end plate.

[0052] Moreover, in this embodiment, as a preferred implementation form, the thickness dimension t of the reinforcing rib 131 is between 2.5 and 3.5 mm. Preferably, the thickness dimension of the reinforcing rib 131 is set to 3 mm, thereby reducing the risk of end plate cracking caused by torsional deformation of the bolt mounting hole 11 due to the expansion of the battery cell, thereby helping to enhance the stiffness and strength of the end plate.

[0053] It is worth noting that the thickness of the reinforcing rib 131 should not be too thick or too thin. If the thickness of the reinforcing rib 131 is too thick, it may affect the appearance quality of the end plate, resulting in depressions or shrinkage marks on the surface of the product. If it is too thin, it may affect the strength of the end plate and may have limited effect on increasing the structural strength of the end plate. Under the premise of not affecting the rigidity and strength of the end plate, the thickness of the reinforcing rib 131 can also be set to 2.5mm or 3.5mm.

[0054] In addition, in this embodiment, as a preferred implementation form, Figure 7 and Figure 8As shown, when the reinforcing rib 131 is in an arc shape when viewed from top to bottom, the reinforcing rib 131 takes the center O of the bolt mounting hole 111 as the center, and the radius R of the reinforcing rib 131 taking the bolt mounting hole 111 as the center is between 50 and 120 mm. Preferably, the radius R can be set to 70 mm, which is conducive to saving space, and when it does not affect the assembly of the bolts during the installation process, R can also be set to 90 mm or 110 mm, which is conducive to ensuring the quality of the bolt connection, improving the rigidity of the bolt mounting hole 11, and reducing the risk of cracking caused by alternating torsional deformation at the bolt mounting hole 11.

[0055] At the same time, in this embodiment, as a preferred implementation form, Figures 4 to 6 As shown, when viewed from top to bottom, the reinforcing rib 131 is in a straight line, the angle between the reinforcing rib 131 and the first side wall 121 is between 30 and 60 degrees, and the angle between the reinforcing rib 131 and the third side wall 123 is between 30 and 60 degrees.

[0056] In a specific implementation, when the space of the battery pack is limited, a straight reinforcing rib 131 may be used. Preferably, an angle C2 between the reinforcing rib 131 and the first side wall 121 and an angle C1 between the third side wall 122 are both set to 45°.

[0057] In this way, the risk of cracking of the end plate caused by alternating torsional deformation of the bolt mounting hole 11 due to cyclic expansion of the battery cell can be reduced, and space can be saved. In specific implementation, C1 and C2 can also be set to 30° or 60° according to actual conditions.

[0058] In addition, in this embodiment, as a preferred implementation form, in the height direction of the board body 1, the top of the reinforcing rib 131 is not higher than the top of the board body 1. The setting that the top of the reinforcing rib 131 is lower than the top of the board body 1 can not only avoid the rib part being damaged by force due to the excessive height of the reinforcing rib 131, thereby reducing the rigidity of the product, but also save the Z-direction space of the battery pack.

[0059] Furthermore, in this embodiment, as a preferred implementation form, Figure 1 and Figure 2 As shown, a reinforcing rib 14 is provided between the boss 11 and the plate body 1, which is beneficial to better restrain the expansion force generated by the expansion of the battery core.

[0060] In a specific implementation, the reinforcing ribs 14 include a plurality of transverse ribs 141 and longitudinal ribs 142. The transverse ribs 141 and longitudinal ribs 142 are cross-connected and arranged to improve the durability and reliability of the end plate, thereby extending the service life of the end plate and reducing maintenance costs.

[0061] At the same time, at the connection between the transverse rib 141 and the boss 11, the transverse rib 141 is provided with a certain curvature, thereby not only increasing the rigidity and stability of the end plate and improving the overall structural strength, but also better dispersing and transmitting stress when bearing the expansion force of the battery cell, thereby reducing the risk of structural damage, and making the structural appearance more smooth and beautiful, thereby improving the market competitiveness of the product.

[0062] In addition, the end plate is made of one-piece injection molding, which can improve production efficiency, effectively reduce the waste of raw materials, and also help to improve lightweight design.

[0063] Embodiment 2

[0064] This embodiment relates to a battery pack, in which the end plate in the first embodiment is provided.

[0065] The battery pack of this embodiment is provided with the end plate in the first embodiment, and the bolt preload force borne by the module when it is installed on the rear end plate of the battery pack and the expansion force generated by the expansion of the battery cell are considered, while the sliding friction between the various components during the expansion of the module are taken into consideration for analysis. According to its force transmission path and in combination with the material properties of the injection molded parts themselves, the cracking phenomenon of the traditional module end plate is specifically solved, and while meeting the load-bearing requirements, it is lightweight in design, thereby having better product quality and market competitiveness.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An end plate, characterized in that: It includes a plate body, a boss provided on the plate body, and a bolt mounting hole provided on the boss; The boss is arranged extending along the height direction of the plate body, the bolt mounting hole passes through the boss along the height direction of the plate body, and the top of the plate body is provided with a groove connected to the top of the boss; The groove includes a first side wall close to the middle position of the length direction of the plate body, a second side wall away from the middle position of the length direction of the plate body, and a third side wall connected between the first side wall and the second side wall, and a reinforcement structure is provided between at least the first side wall and the third side wall.

2. The end plate according to claim 1, characterized in that: The reinforcement structure includes a reinforcement rib connected between the first side wall and the third side wall, and the bottom of the reinforcement rib is connected to the top of the boss.

3. The end plate according to claim 2, characterized in that: Along the height direction of the plate body, looking from top to bottom, the reinforcing ribs are in arc shape and / or straight line shape.

4. The end plate according to claim 3, characterized in that: The thickness dimension t of the reinforcing rib is between 2.5 and 3.5 mm.

5. The end plate according to claim 3, characterized in that: When viewed from top to bottom, the reinforcing rib is in an arc shape, the reinforcing rib takes the center O of the bolt mounting hole as the center, and the radius R of the reinforcing rib taking the bolt mounting hole as the center is between 50 and 120 mm.

6. The end plate according to claim 3, characterized in that: Looking from top to bottom, when the reinforcing rib is in a straight line, the angle between the reinforcing rib and the first side wall is between 30 and 60 degrees, or the angle between the reinforcing rib and the third side wall is between 30 and 60 degrees.

7. The end plate according to claim 2, characterized in that: In the height direction of the plate body, the top of the reinforcing rib is not higher than the top of the plate body.

8. The end plate according to claim 1, characterized in that: A reinforcing rib is provided between the boss and the plate body.

9. The end plate according to any one of claims 1 to 8, characterized in that: The end plate is integrally injection molded.

10. A battery pack, characterized in that: The battery pack is provided with the end plate according to any one of claims 1 to 9.

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