Cover plate structure, cover plate assembly and battery cell

Abstract

The application relates to the technical field of batteries and discloses a cover plate structure, a cover plate assembly and a battery cell. The cover plate structure comprises a cover plate body provided with a plurality of mounting through holes, and the thickness of the cover plate body along the Z direction is T; a plurality of reinforcing structures are arranged on the cover plate body, the reinforcing structures are arranged at intervals, the reinforcing structures are arranged at intervals with the mounting through holes, the reinforcing structures are either sunken grooves or convex bumps; the sunken grooves are recessed from at least part of the surface of the cover plate body along the Z direction, the groove depth of the sunken grooves along the Z direction is t, and the relationship between t and T satisfies the formula: 0 < t / T <= 0.4; the convex bumps protrude from the surface of the cover plate body along the Z direction and the protruding height is h, and the relationship between h and T satisfies the formula: 0 < h / T <= 3. The structural strength of the cover plate body can be reinforced without increasing the thickness of the cover plate body, the cover plate structure has sufficient structural strength, the cover plate structure is light in weight, and the material cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to cover plate structures, cover plate assemblies, and battery cells. Background Technology

[0002] The cover plate body is a crucial component of the cover plate assembly, which includes the cover plate body and integrated structures such as electrode posts and explosion-proof valves. The cover plate assembly is used for assembly and welding with the housing to encapsulate the electrode group inside the housing. When the battery cell is exposed to vibration and shock, the cover plate assembly is subjected to significant shear force impacts. If the cover plate body is not strong enough, it can lead to failure in weak areas such as the welded joints between the cover and the housing. Existing cover plate bodies are typically flat, resulting in poor structural strength. Increasing the thickness of the cover plate body to improve its structural strength would increase material costs and weight, thereby increasing the cost and weight of the battery cell and hindering the achievement of lightweight battery cells. Summary of the Invention

[0003] In view of this, the present invention provides a cover plate structure, a cover plate assembly, and a battery cell to solve the problems of poor structural strength, high cost, and high weight of the cover plate body.

[0004] In a first aspect, the present invention provides a cover plate structure, comprising: a cover plate body having a plurality of mounting through holes, the thickness of the cover plate body along the Z direction being T; a plurality of reinforcing structures constructed on the cover plate body, the plurality of reinforcing structures being spaced apart from each other, and the reinforcing structures being spaced apart from the mounting through holes, the reinforcing structures being grooves or protrusions; the grooves being formed by at least a portion of the surface of the cover plate body being recessed along the Z direction, the groove depth along the Z direction being t, and t and T satisfying the relationship: 0 < t / T ≤ 0.4; the protrusions along the Z direction protruding from the surface of the cover plate body with a protrusion height of h, and h and T satisfying the relationship: 0 < h / T ≤ 3.

[0005] Beneficial effects: By setting several spaced grooves or protrusions on the cover plate body, an alternating concave-convex structure is formed on the surface of the cover plate body, which can enhance the structural strength of the cover plate body. When the reinforcing structure is a groove, by limiting the ratio t / T between the groove depth and the thickness of the cover plate body to be greater than 0 and less than or equal to 0.4, the groove depth is designed within a reasonable range, avoiding the loss of structural reinforcement effect due to excessive groove depth relative to the thickness of the cover plate body, ensuring that the groove is formed on the cover plate body and that the groove can effectively enhance the structural strength of the cover plate body. When the reinforcing structure is a protrusion, by limiting the ratio h / T between the protrusion height of the protrusion relative to the surface of the cover plate body and the thickness of the cover plate body to be greater than 0 and less than or equal to 3, the protrusion is ensured to be present on the cover plate body and that the protrusion can be formed smoothly, ensuring the forming yield of the cover plate structure and effectively enhancing the structural strength of the cover plate body. Thus, the structural strength of the cover plate body can be enhanced without increasing the thickness of the cover plate body, ensuring that the cover plate structure has sufficient structural strength, achieving lightweighting, and reducing material costs.

[0006] In one optional embodiment, the thickness T of the cover plate body along the Z direction ranges from 0.5 mm to T ≤ 10 mm.

[0007] And / or, the depth t of the settling tank along the Z direction is in the range of: 0 < t ≤ 4 mm;

[0008] And / or, the height h of the convex bulge protruding from the surface of the cover plate body along the Z direction is in the range of: 0 < h ≤ 30 mm.

[0009] Beneficial effects: By limiting T to a value between 0.5 mm and 10 mm, the cover plate body has a reasonable thickness, which can ensure that the cover plate body itself has sufficient structural strength, thereby ensuring the reliability of the cover plate body and the safety of the battery cell, while avoiding material waste and helping to reduce the weight of the cover plate body and achieve lightweighting of the battery cell.

[0010] And / or, by limiting the depth t of the sinking groove to be greater than 0 and less than or equal to 4 mm, the sinking groove is ensured to have a reasonable depth. This ensures that the sinking groove is formed on the cover plate body to strengthen the structural strength of the cover plate body, while avoiding excessive depth which would result in insufficient residual thickness of the solid part corresponding to the sinking groove on the cover plate body. This avoids excessive damage to the structure of the cover plate body, allowing the sinking groove to effectively strengthen the structural strength of the cover plate body and improve the reliability of the cover plate body.

[0011] And / or, by limiting h to be greater than 0 and less than or equal to 30 mm, it is possible to ensure that a bulge is formed on the cover plate body to strengthen the structural strength of the cover plate body, while avoiding the bulge height being too large and difficult to process smoothly, thereby ensuring the smooth forming of the cover plate body and the reinforcing structure, and ensuring that the reinforcing structure can effectively improve the structural strength of the cover plate body.

[0012] In one alternative embodiment, the shape of the reinforcing structure is one or more of the following: polygonal, circular, elliptical, and annular.

[0013] Beneficial effects: Polygons have multiple sides, which can make reasonable use of the space on the cover plate body and improve the structural strength of the cover plate body; circular structures are simple and easy to process and form; elliptical structures are simple, easy to process and form, and have a larger area, resulting in better reinforcement; rings can not only make the reinforcing structure have a large outline area, but also form structures that are raised or recessed relative to the ring area on the inner side of the inner ring and the outer side of the outer ring, respectively, further increasing the complexity of the alternating concave and convex surfaces of the cover plate body, thereby strengthening the structural strength of the cover plate body.

[0014] In one optional embodiment, the reinforcing structure is a sinkhole and the shape of the reinforcing structure is rectangular, and the cover plate body has two first side edges arranged opposite to each other along the Y direction and two second side edges arranged opposite to each other along the X direction.

[0015] The recess includes a first rectangular groove, which is disposed between the mounting through hole and the first side and / or between two adjacent mounting through holes; the first rectangular groove has two first long sides arranged opposite each other along the Y direction and two first wide sides arranged opposite each other along the X direction, the first long side has a dimension L1 along the X direction and the first wide side has a dimension W1 along the Y direction, wherein L1≥W1 and 1≤L1 / W1≤4;

[0016] And / or, the recess includes a second rectangular groove, the second rectangular groove being disposed between the mounting through hole and the second side and / or between two adjacent mounting through holes; the second rectangular groove has two second long sides arranged opposite each other along the X direction, and two second wide sides arranged opposite each other along the Y direction, the dimension of the second long side along the Y direction is L2, the dimension of the second wide side along the X direction is W2, wherein L2≥W2, and 1≤L2 / W2≤4.

[0017] Beneficial effects: By setting a first rectangular groove between the mounting through hole and the first side, the structural strength of the area between the mounting through hole and the first side on the cover plate body can be strengthened, that is, the structural strength of the edge part of the cover plate body can be strengthened, thereby ensuring the structural strength after the edge of the cover plate body is welded to the shell. By setting a first rectangular groove between two adjacent mounting through holes, the structural strength around the mounting through hole can be strengthened. Furthermore, by limiting the length-to-width ratio of the first rectangular groove to between 1 and 2, it can be ensured that the first rectangular groove will not interfere with the mounting through hole, which facilitates the layout of the first rectangular groove and ensures that a sufficient number of first rectangular grooves can be set to effectively strengthen the structural strength of the cover plate body. At the same time, it can also avoid the first rectangular groove having too large a length-to-width ratio, which would cause it to fail to strengthen the structure of the cover plate body or make the cover plate body weaker. It can also ensure the strengthening effect of the first rectangular groove on the structural strength of the cover plate body, thereby ensuring the reliability of the cover plate body.

[0018] And / or, by setting a second rectangular groove between the mounting through hole and the second side, the structural strength of the area between the mounting through hole and the second side on the cover plate body can be strengthened, that is, the structural strength of the edge part of the cover plate body can be strengthened, thereby ensuring the structural strength after the edge of the cover plate body is welded to the shell. By setting a second rectangular groove between two adjacent mounting through holes, the structural strength around the mounting through hole can be strengthened. And by limiting the length-to-width ratio of the second rectangular groove to a value between 1 and 2, it can be ensured that the second rectangular groove has a sufficient opening area, thereby ensuring the strengthening effect on the structural strength of the cover plate body, and ensuring that the second rectangular groove does not interfere with the mounting through hole, which facilitates the layout of the second rectangular groove, ensuring that a sufficient number of second rectangular grooves can be set to effectively strengthen the structural strength of the cover plate body, and also avoiding the second rectangular groove having an excessively large length-to-width ratio, which would cause its structural strengthening effect on the cover plate body to fail or make the cover plate body weaker. Similarly, it can ensure the strengthening effect of the second rectangular groove on the structural strength of the cover plate body, thereby ensuring the reliability of the cover plate body.

[0019] In one optional implementation, the value range of L1 is: 0.5 mm ≤ L1 ≤ 40 mm, and the value range of W1 is: 0.5 mm ≤ W1 ≤ 40 mm.

[0020] And / or, the value range of L2 is: 0.5 mm ≤ L2 ≤ 40 mm, and the value range of W2 is: 0.5 mm ≤ W2 ≤ 40 mm.

[0021] Beneficial effects: By limiting L1 to a value between 0.5 mm and 40 mm, and W1 to a value between 0.5 mm and 40 mm, the first rectangular groove has reasonable length and width dimensions. This ensures that the first rectangular groove can be formed smoothly and has sufficient opening area, thereby improving the structural reinforcement effect of the first rectangular groove on the cover plate body. At the same time, it can avoid excessive damage to the structure of the cover plate body due to excessive length or width of the first rectangular groove, thus ensuring that the first rectangular groove can effectively strengthen the structural strength of the cover plate body.

[0022] And / or, by limiting L2 to a value between 0.5 mm and 40 mm, and W2 to a value between 0.5 mm and 40 mm, the second rectangular groove is guaranteed to have reasonable length and width dimensions. This ensures that the second rectangular groove can be formed smoothly and has sufficient opening area, thereby improving the structural reinforcement effect of the second rectangular groove on the cover plate body. At the same time, it avoids excessive damage to the structure of the cover plate body due to excessive length or width of the second rectangular groove, thus ensuring that the second rectangular groove can effectively strengthen the structural strength of the cover plate body.

[0023] In one optional embodiment, the reinforcing structure is a sinkhole, and the distance between two adjacent sinkholes along the X and / or Y directions is g1, and g1 and t satisfy the following relationship: 0.5≤g1 / t≤10, 0.5 mm≤g1≤20 mm.

[0024] Beneficial effects: Ensuring a reasonable spacing between two adjacent sinkers can guarantee the smooth processing and shaping of several sinkers, avoid cracking, improve production yield, and also ensure that an effective structural reinforcement area can be formed between two adjacent sinkers, thereby ensuring the structural reinforcement effect on the cover plate body.

[0025] In one optional embodiment, the reinforcing structure is a convex hull, and the distance between two adjacent convex hulls along the X and / or Y directions is g2, wherein 3 mm ≤ g2 ≤ 50 mm.

[0026] Beneficial effects: Ensuring a reasonable spacing between two adjacent convex humps can avoid interference between them, ensuring smooth convex hump formation, and also avoid insufficient space on the cover plate body. This improves the structural reinforcement effect of the two adjacent convex humps on the cover plate body, ensuring that the reinforcement structure can effectively improve the structural strength of the cover plate body.

[0027] In one alternative embodiment, the edge distance between the reinforcing structure and the edge of the cover plate body along the X and / or Y directions is E, wherein 2 mm ≤ E ≤ 30 mm.

[0028] Beneficial effects: It ensures sufficient bonding area for the insulating tape on the surface of the cover plate, allowing the folded edges of the insulating tape to provide ample bonding area for the top patch, thus preventing the insulating tape and top patch from lifting, ensuring the insulation of the outer side of the battery cell, and improving customer satisfaction. It also prevents the reinforcing structure from being too far from the edge of the cover plate, which would result in insignificant reinforcement. It ensures that the reinforcing structure can effectively enhance the structural strength of the cover plate and that the surface of the cover plate provides sufficient bonding area for the top patch, further preventing the top patch from lifting, reducing the difficulty of bonding the top patch, improving efficiency, and reducing costs.

[0029] Secondly, the present invention also provides a cover plate assembly, comprising: the aforementioned cover plate structure, wherein the mounting through hole in the cover plate structure includes a pole post hole; and a pole post, which passes through the pole post hole. Since the cover plate assembly includes the cover plate structure and has the same effects as the cover plate structure, it will not be described in detail here.

[0030] Thirdly, the present invention also provides a battery cell, comprising: a housing having an open end; an electrode assembly disposed within the inner cavity of the housing; and the aforementioned cover plate assembly covering the open end of the housing. Since the battery cell includes the cover plate assembly and has the same effect as the cover plate assembly, it will not be described further here. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of a first cover plate assembly according to an embodiment of the present invention;

[0033] Figure 2 for Figure 1 Top view of the cover plate assembly shown;

[0034] Figure 3 for Figure 2 A cross-sectional view along the AA direction;

[0035] Figure 4 This is a schematic diagram of the structure of the second cover plate assembly according to an embodiment of the present invention;

[0036] Figure 5 for Figure 4 Top view of the cover plate assembly shown;

[0037] Figure 6 for Figure 4A partially enlarged schematic diagram of the cross-sectional view of the cover plate assembly and housing after assembly;

[0038] Figure 7 This is a schematic diagram of the structure of a third cover plate assembly according to an embodiment of the present invention;

[0039] Figure 8 for Figure 7 Top view of the cover plate assembly shown;

[0040] Figure 9 for Figure 8 Cross-sectional view along the BB direction;

[0041] Figure 10 This is a schematic diagram of the structure of the fourth cover plate assembly according to an embodiment of the present invention;

[0042] Figure 11 for Figure 10 Top view of the cover plate assembly shown;

[0043] Figure 12 for Figure 11 A cross-sectional view along the CC direction;

[0044] Figure 13 for Figure 10 The front view of the cover plate assembly shown.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. Cover plate body; 101. Pole post hole; 102. Liquid injection hole; 110. First side; 120. Second side; 111. First surface; 112. Second surface; 2. Settling tank; 210. First rectangular groove; 211. First long side; 212. First wide side; 220. Second rectangular groove; 221. Second long side; 222. Second wide side; 3. Protrusion; 4. Pole post; 5. Explosion-proof valve; 6. Housing; 7. Top patch; 8. Insulating tape. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The following is combined with Figures 1 to 13 The following describes embodiments of the present invention.

[0049] According to an embodiment of the present invention, a cover plate structure is provided, comprising: a cover plate body 1 and a plurality of reinforcing structures. The cover plate body 1 has a plurality of mounting through holes, and the thickness of the cover plate body 1 along the Z direction is T; the plurality of reinforcing structures are constructed on the cover plate body 1, the plurality of reinforcing structures being spaced apart from each other, and the reinforcing structures being spaced apart from the mounting through holes; the reinforcing structures are grooves 2 or protrusions 3; the groove 2 is formed by a recess in at least a portion of the surface of the cover plate body 1 along the Z direction, the groove depth of the groove 2 along the Z direction is t, and t and T satisfy the relationship: 0 < t / T ≤ 0.4; the protrusion 3 protrudes from the surface of the cover plate body 1 along the Z direction with a protrusion height of h, and h and T satisfy the relationship: 0 < h / T ≤ 3. Wherein, the Z direction refers to... Figure 3 , Figure 6 , Figure 9 , Figure 12 and Figure 13 The direction indicated by the middle arrow "Z"; the units of t, T, and h are all mm. It should be noted that the cover plate structure has two perpendicular X, Y, and Z directions, where the Z direction is the thickness direction of the cover plate body 1, and the XY plane is the large surface of the cover plate structure.

[0050] It should be noted that by constructing a groove 2 or a bulge 3 on the cover plate body 1, the structure of the cover plate body 1 can be changed, thereby strengthening its structural strength. When the strengthening structure is a groove 2, the groove 2 is formed on the cover plate body 1, where t is the depth of the groove 2 relative to the surface of the cover plate body 1 (t > 0), and T is the thickness of the portion of the cover plate body 1 without the groove 2. If t / T = 0, then there is no groove 2 on the cover plate body 1, and it cannot strengthen the structural strength of the cover plate body 1. If t / T is greater than 0.4, then the groove depth of the groove 2 is too large relative to the thickness of the cover plate body 1, requiring excessive material removal from the cover plate body 1. The residual thickness of the solid portion of the cover plate body 1 corresponding to the groove 2 along the Z direction is too small, resulting in weak structural strength. The structural strengthening effect brought by the groove 2 is ineffective, and it may even become weaker. When the strengthening structure is a bulge 3, the bulge 3 is stamped from a portion of the cover plate body 1. The stamped structure is as follows: Figures 11 to 13 As shown, a protrusion is formed on one side of the cover plate body 1 along the Z direction and a corresponding depression is formed on the other side. The protrusion and the depression together form a convex 3. h is the protrusion height of the convex 3 along the Z direction relative to the surface of the cover plate body 1. h > 0. If h / T = 0, then there is no convex 3, and it cannot play a role in strengthening the structural strength of the cover plate body 1. If h / T is greater than 3, then the protrusion height of the convex 3 is too large relative to the thickness of the cover plate body 1. The distance that the convex 3 needs to be stretched along the Z direction during the stamping process is too large. It is easy to tear during the stamping and stretching process, so that the convex 3 cannot be formed smoothly, the product is unqualified, and the structure of the cover plate body 1 is damaged, and it cannot play a role in strengthening the structure.

[0051] By applying the cover plate structure of this embodiment, and by setting a plurality of spaced-apart grooves 2 or protrusions 3 on the cover plate body 1, the surface of the cover plate body 1 forms an alternating concave-convex structure, which can enhance the structural strength of the cover plate body 1. Furthermore, when the reinforcing structure is a groove 2, by limiting the ratio t / T between the groove depth of the groove 2 and the thickness of the cover plate body 1 to be greater than 0 and less than or equal to 0.4, the groove depth of the groove 2 is designed within a reasonable range, avoiding the loss of structural reinforcement effect due to the groove depth being too large relative to the thickness of the cover plate body 1. This ensures that the groove 2 is formed on the cover plate body 1 and that the groove 2 can... Effectively enhance the structural strength of the cover plate body 1; when the reinforcing structure is a convex 3, by limiting the ratio h / T between the convex height of the convex 3 relative to the surface of the cover plate body 1 and the thickness of the cover plate body 1 to be greater than 0 and less than or equal to 3, it is ensured that the cover plate body 1 has a convex 3 and the convex 3 can be smoothly formed, ensuring the forming yield of the cover plate structure and effectively enhancing the structural strength of the cover plate body 1; thus, the structural strength of the cover plate body 1 can be enhanced without increasing the thickness of the cover plate body 1, ensuring that the cover plate structure has sufficient structural strength, achieving lightweighting, and reducing material costs.

[0052] It should be noted that the cover plate body 1 has a first surface 111 and a second surface 112 arranged opposite to each other along the Z direction. When the cover plate body 1 is assembled into a cover plate assembly and assembled with the housing 6 into a battery cell, the first surface 111 faces the inner cavity of the housing 6, and the second surface 112 faces the outer surface of the housing 6. The reinforcing structure can be provided on the first surface 111, or the reinforcing structure can also be provided on the second surface 112. Specifically, as shown... Figures 1 to 3 , Figures 7 to 9 As shown, the reinforcing structure is a groove 2, which is set on the first surface 111 of the cover plate body 1. Each groove 2 is formed by a portion of the first surface 111 recessed along the Z direction; as shown Figures 4 to 6 As shown, the reinforcing structure is a recessed groove 2, which is provided on the second surface 112 of the cover plate body 1. Each recessed groove 2 is formed by a portion of the second surface 112 recessed along the Z direction; as shown Figures 10 to 13 As shown, the reinforcing structure is a convex hull 3, the number of convex hulls 3 n≥1, the convex hull 3 protrudes in the Z direction relative to the first surface 111, and / or, the convex hull 3 protrudes in the Z direction relative to the second surface 112. That is, along the Z direction, several convex hulls 3 on the cover plate body 1 can all protrude in the same direction, or they can protrude in different directions.

[0053] Optionally, the value of h / T is any one of 0.1, 0.5, 1, 1.5, 2, 2.5, 3 or a value between any two values.

[0054] In one embodiment, the mounting through hole includes a pole post hole 101, an explosion-proof valve hole, and an injection hole 102. The pole post hole 101 is suitable for installing a pole post 4, the explosion-proof valve hole is suitable for installing an explosion-proof valve, and the injection hole 102 is used to inject electrolyte into the cell. When electrolyte injection is not required, the injection hole 102 is suitable for installing a sealing pin.

[0055] Optionally, a reinforcing structure can be arranged globally in the area of ​​the cover plate body 1, except for the mounting through holes, to effectively enhance the structural strength of the cover plate body 1. It is understood that, as an alternative implementation, reinforcing structures can also be provided only in the weaker areas of the cover plate body 1, such as around the explosion-proof valve hole, around the pole hole 101, and near the edge of the cover plate body 1. This strengthens the structural strength of the weak areas of the cover plate body 1 while reducing processing difficulty. It should be noted that the edge of the cover plate body 1 is used to mate with and weld to the housing 6, and therefore has relatively weak strength; the mounting through holes are typically used to install poles, and the area around these mounting through holes is prone to stress concentration. By providing a reinforcing structure, these stresses can be effectively dispersed, improving the reliability of the cover plate body 1 and the safety of the battery cell.

[0056] In one embodiment, further combination Figure 3 and Figure 12 As shown, the thickness T of the cover plate body 1 along the Z direction ranges from 0.5 mm to T to 10 mm.

[0057] It should be noted that T represents the thickness of the cover plate body 1, i.e., the thickness of the portion of the cover plate body 1 without reinforcing structures. If T is less than 0.5 mm, the thickness of the cover plate body 1 is too small, resulting in insufficient structural strength and making it prone to deformation during processing or use, leading to poor reliability. If T is greater than 10 mm, the thickness of the cover plate body 1 is too large, wasting material and increasing weight, which is detrimental to improving the energy density of the battery cell and achieving lightweight design. Therefore, by limiting T to a value between 0.5 mm and 10 mm, the cover plate body 1 has a reasonable thickness. This ensures sufficient structural strength for the cover plate body 1, thereby guaranteeing its reliability and the safety of the battery cell, while also avoiding material waste and reducing its weight, thus achieving lightweight design of the battery cell.

[0058] Optionally, T can be any value among 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm, or a value between any two of these values.

[0059] In one embodiment, further combination Figure 3As shown, the range of values ​​for the depth t of the settling tank 2 along the Z direction is: 0 < t ≤ 4 mm. It should be noted that t is the recess depth of the groove 2 relative to the surface of the cover plate body 1 where the groove 2 is formed. In order to ensure that the groove 2 is formed on the cover plate body 1, t must be greater than 0. If t is greater than 4 mm, the groove depth of the groove 2 is too large. After the groove 2 is formed, the residual thickness (Tt) of the solid part corresponding to the groove 2 along the Z direction on the cover plate body 1 is too small. The structural strength of this part is weak and it is easy to be damaged when the cover plate body 1 is under stress. The structural reinforcement effect of the groove 2 on the cover plate body 1 will fail, and it may even lead to the cover plate body 1 becoming weaker. Therefore, by limiting the groove depth t of the groove 2 to be greater than 0 and less than or equal to 4 mm, the groove 2 is ensured to have a reasonable groove depth. This ensures that the groove 2 is formed on the cover plate body 1 to strengthen the structural strength of the cover plate body 1, and also avoids that the groove depth is too large, resulting in the residual thickness of the solid part corresponding to the groove 2 on the cover plate body 1 being too small. This avoids excessive damage to the structure of the cover plate body 1, so that the groove 2 can effectively strengthen the structural strength of the cover plate body 1 and improve the reliability of the cover plate body 1.

[0060] Optionally, t can take any value from 0.01 mm, 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, or a value between any two values.

[0061] In one embodiment, further combination Figure 12 As shown, the height h of the protrusion 3 protruding from the surface of the cover plate body 1 along the Z direction ranges from 0 to 30 mm. It should be noted that the surface of the cover plate body 1 refers to either the first surface 111 or the second surface 112. When the protrusion 3 protrudes from the first surface 111 along the Z direction, h refers to the vertical distance between the side of the protrusion 3 facing away from the first surface 111 and the first surface 111 along the Z direction. When the protrusion 3 protrudes from the second surface 112 along the Z direction, h refers to the vertical distance between the side of the protrusion 3 facing away from the second surface 112 and the first surface 111 along the Z direction. To ensure that the cover plate body 1 has the protrusion 3, h must be greater than 0. If h is greater than 30 mm, the distance the protrusion 3 protrudes from the surface of the cover plate body 1 is too large, and the distance the protrusion 3 needs to be stretched along the Z direction during the stamping process is too large, making it prone to tearing during stamping and stretching, thus preventing the protrusion 3 from being successfully formed. Therefore, by limiting h to be greater than 0 and less than or equal to 30 mm, it is possible to ensure that the cover plate body 1 has a protrusion 3 to strengthen the structural strength of the cover plate body 1, and to avoid the protrusion height of the protrusion 3 being too large and difficult to process smoothly, thereby ensuring the smooth forming of the cover plate body 1 and the reinforcing structure, and ensuring that the reinforcing structure can effectively improve the structural strength of the cover plate body 1.

[0062] Optionally, h can be any value among 0.1 mm, 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm, or a value between any two of these values.

[0063] In one embodiment, the reinforcing structure is polygonal in shape. When the reinforcing structure is a recessed groove 2, the area enclosed by the polygon is entirely concave to form a polygonal opening in the recessed groove 2; when the reinforcing structure is a convex hull 3, the area enclosed by the polygon is entirely convex to form a polygonal convex hull 3. The polygon has multiple sides, which can make reasonable use of the space on the cover plate body 1 and improve the structural strength of the cover plate body 1. Optionally, the polygon can be a triangle, quadrilateral, pentagon, hexagon, etc., wherein the quadrilateral can be a rectangle, trapezoid, rhombus, etc. Figures 1 to 6 , Figures 10 to 13 The reinforcing structures shown are all quadrilaterals.

[0064] In other embodiments, the reinforcing structure is circular, which is simple and easy to process and shape.

[0065] In other embodiments, the reinforcing structure is elliptical. Elliptical structures are simple, easy to process and shape, and have a large area, resulting in a better reinforcing effect.

[0066] In other embodiments, the reinforcing structure is annular. An annular shape allows the reinforcing structure to have a large outline area, and it also allows for protrusions or depressions on the inner side of the inner ring and the outer side of the outer ring, respectively, further increasing the complexity of the alternating convex and concave surfaces of the cover plate body 1, thereby strengthening the structural strength of the cover plate body 1. Optionally, the annular shape can be a polygonal ring, a circular ring, an elliptical ring, etc.

[0067] It should be noted that the reinforcing structures on the cover plate body 1 can all be any one of polygons, circles, ellipses, or rings, or a combination of two or more of these shapes, offering a wide range of choices. For example... Figures 7 to 8 As shown, the reinforcing structures on the cover plate body 1 include square rings, pentagonal rings, and circular rings. By simultaneously setting reinforcing structures of various shapes on the cover plate body 1, the space on the cover plate body 1 can be rationally utilized, and the distribution area of ​​the reinforcing structures on the cover plate body 1 can be maximized.

[0068] It should be noted that the shape of the reinforcing structure refers to the outline shape of the reinforcing structure as an orthographic projection along the Z direction onto the surface of the cover plate.

[0069] In one embodiment, such as Figures 1 to 6As shown, the reinforcing structure is a recessed groove 2 and the shape of the reinforcing structure is rectangular. The cover plate body 1 has two first side edges 110 arranged opposite each other along the Y direction and two second side edges 120 arranged opposite each other along the X direction. The recessed groove 2 includes a first rectangular groove 210, which is disposed between the mounting through hole and the first side edge 110, and / or the first rectangular groove 210 is disposed between two adjacent mounting through holes. The first rectangular groove 210 has two first long sides 211 arranged opposite each other along the Y direction and two first wide sides 212 arranged opposite each other along the X direction. The dimension of the first long side 211 along the X direction is L1, and the dimension of the first wide side 212 along the Y direction is W1, wherein L1≥W1, and 1≤L1 / W1≤4.

[0070] Wherein, the X direction refers to Figures 1 to 2 , Figures 4 to 5 The direction indicated by the middle arrow ("X") is the direction of the Y direction. Figures 1 to 6 The direction indicated by the middle arrow "Y" is perpendicular to each other in the X, Y, and Z directions. The dimension of the first side 110 along the X direction is larger than the dimension of the second side 120 along the Y direction. There are multiple first rectangular slots 210. Multiple first rectangular slots 210 are respectively provided on both sides of the mounting through hole along the Y direction. Multiple first rectangular slots 210 located on the same side of the mounting through hole are spaced apart along the X direction. Multiple first rectangular slots 210 located between two adjacent mounting through holes are spaced apart along the Y direction.

[0071] Further integration Figure 2 As shown, the first long side 211 and the second wide side 222 are perpendicular to each other. The shape of the first rectangular groove 210 is a square or a rectangle. When the shape of the first rectangular groove 210 is a square, L1=W1. When the shape of the first rectangular groove 210 is a rectangle, the dimension L1 of the first long side 211 along the X direction is the length of the rectangle, and the dimension W1 of the first wide side 212 along the Y direction is the width of the rectangle. The length of the first long side 211 is greater than the length of the second wide side 222. L1 / W1 represents the aspect ratio of the first rectangular groove 210. If L1 / W1 is less than 1, the aspect ratio is too small, and the length of the first long side 211 is less than the length of the first wide side 212. The first rectangular groove 210 may interfere with the mounting through hole, making it inconvenient to arrange the first rectangular groove 210 on the cover plate body 1. This will reduce the number of first rectangular grooves 210 on the cover plate body 1, that is, reduce the number of recessed grooves 2, and cannot effectively strengthen the structural strength of the cover plate body. If L1 / W1 is greater than 4, the aspect ratio is too large, and the first rectangular groove 210 is narrow and strip-shaped, which will fail to strengthen the structure of the cover plate body 1 and may even make the cover plate body 1 weaker.

[0072] Therefore, by setting a first rectangular groove 210 between the mounting through hole and the first side 110, the structural strength of the area on the cover plate body 1 located between the mounting through hole and the first side 110 can be strengthened, that is, the structural strength of the edge part of the cover plate body 1 can be strengthened, thereby ensuring the structural strength after the edge of the cover plate body 1 is welded to the shell 6. By setting a first rectangular groove 210 between two adjacent mounting through holes, the structural strength around the mounting through hole can be strengthened. Furthermore, by limiting the aspect ratio of the first rectangular groove 210 to between 1 and 4, it can be ensured that the first rectangular groove 210 will not interfere with the mounting through hole, which facilitates the layout of the first rectangular groove 210 and ensures that a sufficient number of first rectangular grooves 210 can be set to effectively strengthen the structural strength of the cover plate body 1. At the same time, it can also avoid the first rectangular groove 210 having an excessively large aspect ratio, which would cause it to fail to strengthen the structure of the cover plate body 1 or make the cover plate body 1 weaker. Similarly, it can ensure the strengthening effect of the first rectangular groove 210 on the structural strength of the cover plate body 1, thereby ensuring the reliability of the cover plate body 1.

[0073] Optionally, the value of L1 / W1 can be any one of 1, 1.5, 2, 2.5, 3, 3.5, 4 or a value between any two of them.

[0074] In one embodiment, the reinforcing structure is a recessed groove 2 with a rectangular shape. The cover plate body 1 has two first side edges 110 arranged opposite each other along the Y direction and two second side edges 120 arranged opposite each other along the X direction. The recessed groove 2 includes a second rectangular groove 220, which is disposed between the mounting through hole and the second side edge 120, and / or the second rectangular groove 220 is disposed between two adjacent mounting through holes. The second rectangular groove 220 has two second long sides 221 arranged opposite each other along the X direction and two second wide sides 222 arranged opposite each other along the Y direction. The dimension of the second long side 221 along the Y direction is L2, and the dimension of the second wide side 222 along the X direction is W2, wherein L2≥W2, and 1≤L2 / W2≤4. There are multiple second rectangular grooves 220. Multiple second rectangular grooves 220 are respectively disposed on both sides of the mounting through hole along the X direction. Multiple second rectangular grooves 220 located on the same side of the mounting through hole are spaced apart along the Y direction. At least one second rectangular groove 220 is disposed between two adjacent mounting through holes.

[0075] Further integration Figure 2As shown, the second long side 221 and the second wide side 222 are perpendicular to each other. The shape of the second rectangular groove 220 is a square or a rectangle. When the shape of the second rectangular groove 220 is a square, L2 = W2. When the shape of the second rectangular groove 220 is a rectangle, the dimension L2 of the second long side 221 along the Y direction is the length of the rectangle, and the dimension W2 of the second wide side 222 along the X direction is the width of the rectangle. The length of the second long side 221 is greater than the length of the second wide side 222. L2 / W2 represents the aspect ratio of the second rectangular groove 220. If L2 / W2 is less than 1, the aspect ratio is too small, the length of the first long side 211 is less than the length of the first wide side 212, the opening area of ​​the second rectangular groove 220 is insufficient, which is not conducive to improving the structural strength of the cover plate body 1, or the second rectangular groove 220 may interfere with the mounting through hole, making it inconvenient to arrange the second rectangular groove 220 on the cover plate body 1, which will lead to a reduction in the number of second rectangular grooves 220 on the cover plate body 1, that is, a reduction in the number of recessed grooves 2, which cannot effectively strengthen the structural strength of the cover plate body. If L2 / W2 is greater than 4, the aspect ratio is too large, the second rectangular groove 220 is narrow, which fails to strengthen the structure of the cover plate body 1, and may even make the cover plate body 1 weaker.

[0076] Therefore, by providing a second rectangular groove 220 between the mounting through hole and the second side 120, the structural strength of the area on the cover plate body 1 located between the mounting through hole and the second side 120 can be strengthened, that is, the structural strength of the edge part of the cover plate body 1 can be strengthened, thereby ensuring the structural strength after the edge of the cover plate body 1 is welded to the shell 6. By providing a second rectangular groove 220 between two adjacent mounting through holes, the structural strength around the mounting through hole can be strengthened. Furthermore, by limiting the aspect ratio of the second rectangular groove 220 to between 1 and 4, it can be ensured that the second rectangular groove 220 has sufficient strength. Sufficient opening area ensures the strengthening effect on the structural strength of the cover plate body 1 and prevents the second rectangular groove 220 from interfering with the mounting through hole. It facilitates the layout of the second rectangular groove 220, ensuring that a sufficient number of second rectangular grooves 220 can be set to effectively strengthen the structural strength of the cover plate body 1. It also avoids the second rectangular groove 220 having an excessively large length-to-width ratio, which could lead to its failure to strengthen the structural strength of the cover plate body 1 or make the cover plate body 1 weaker. It can also ensure the strengthening effect of the second rectangular groove 220 on the structural strength of the cover plate body 1, thereby ensuring the reliability of the cover plate body 1.

[0077] Optionally, the value of L2 / W2 can be any one of 1, 1.5, 2, 2.5, 3, 3.5, 4 or a value between any two of them.

[0078] Preferably, the sink 2 includes a first rectangular sink 210 and a second rectangular sink 220, and the sink 2 is arranged on the entire cover plate body 1, thereby effectively strengthening the structural strength of the cover plate body 1.

[0079] In one embodiment, the value range of L1 is 0.5 mm ≤ L1 ≤ 40 mm, and the value range of W1 is 0.5 mm ≤ W1 ≤ 40 mm. It should be noted that L1 is the dimension of the first rectangular groove 210 along its length. If L1 is less than 0.5 mm, the length of the first rectangular groove 210 is too small, the opening area of ​​the first rectangular groove 210 is insufficient, and the structural reinforcement effect on the cover plate body 1 is not obvious. If L1 is greater than 40 mm, the length of the first rectangular groove 210 is too large, requiring excessive material removal from the cover plate body 1, excessively damaging the structural strength of the cover plate body 1 itself, making it prone to damage when the cover plate body 1 is under stress, and the structural reinforcement effect of the groove 2 on the cover plate body 1 will be ineffective, and may even lead to the cover plate body 1 becoming weaker. W1 is the dimension of the first rectangular groove 210 along its width. If W1 is less than 0.5 mm, the width of the first rectangular groove 210 is too small, the structural reinforcement effect of the first rectangular groove 210 on the cover plate body 1 along the width direction is not obvious, and the processing difficulty is relatively high. If W1 is greater than 40 mm, the length of the first rectangular groove 210 is too large, requiring excessive material removal from the cover plate body 1, excessively damaging the structural strength of the cover plate body 1, and easily damaging the cover plate body 1 under stress. If the width of the first rectangular groove 210 is too large, too much material needs to be removed from the cover plate body 1, which will excessively damage the structural strength of the cover plate body 1 itself. The cover plate body 1 is easily damaged when subjected to force, and the structural reinforcement effect brought by the sink 2 to the cover plate body 1 will fail, and may even lead to the cover plate body 1 becoming weaker.

[0080] Therefore, by limiting L1 to a value between 0.5 mm and 40 mm, and W1 to a value between 0.5 mm and 40 mm, the first rectangular groove 210 is guaranteed to have reasonable length and width dimensions. This ensures that the first rectangular groove 210 can be formed smoothly and has sufficient opening area, thereby improving the structural reinforcement effect of the first rectangular groove 210 on the cover plate body 1. At the same time, it avoids excessive damage to the structure of the cover plate body 1 due to excessive length or width of the first rectangular groove 210, thus ensuring that the first rectangular groove 210 can effectively strengthen the structural strength of the cover plate body 1.

[0081] Optionally, the value of L1 is any one of 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or a value between any two of these values.

[0082] Optionally, the value of W1 is any one of 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or a value between any two of these values.

[0083] In one embodiment, the value range of L2 is 0.5 mm ≤ L2 ≤ 40 mm, and the value range of W2 is 0.5 mm ≤ W2 ≤ 40 mm. Similarly, L2 is the dimension of the second rectangular groove 220 along its length direction, and W2 is the dimension of the second rectangular groove 220 along its width direction. By limiting the value of L2 to between 0.5 mm and 40 mm, and the value of W2 to between 0.5 mm and 40 mm, the second rectangular groove 220 is guaranteed to have reasonable length and width dimensions. This ensures that the second rectangular groove 220 can be formed smoothly and has sufficient opening area, thereby improving the structural reinforcement effect of the second rectangular groove 220 on the cover plate body 1. At the same time, it avoids the second rectangular groove 220 being too long or too wide, which would excessively damage the structure of the cover plate body 1. This ensures that the second rectangular groove 220 can effectively strengthen the structural strength of the cover plate body 1.

[0084] Optionally, the value of L2 is any one of 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or a value between any two of these values.

[0085] Optionally, the value of W2 is any one of 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or a value between any two of these values.

[0086] In one embodiment, further combination Figure 2 As shown, the reinforcing structure is a sinkhole 2. The distance between two adjacent sinkholes 2 along the X and / or Y directions is g1. The relationship between g1 and t is: 0.5≤g1 / t≤10, 0.5 mm≤g1≤20 mm. It should be noted that the units of g1 and t are both mm. For two adjacent sinkholes 2 spaced apart along the X direction, g1 is the distance between the two adjacent sinkholes 2 along the X direction; for two adjacent sinkholes 2 spaced apart along the Y direction, g1 is the distance between the two adjacent sinkholes 2 along the Y direction. The area between two adjacent sinkholes 2 forms a rib relative to the bottom of the sinkhole 2, and the rib strengthens the structure of the cover plate body 1; t is the recess depth of the sinkhole 2. If g1 / t is less than 0.5, the distance between two adjacent sinkers 2 is too small relative to the depth of sinker 2, making it difficult to process and form. The position between two adjacent sinkers 2 is relatively weak and prone to cracking, affecting the production yield and failing to effectively strengthen the structure of the cover plate body 1. If g1 / t is greater than 10, the distance between two adjacent sinkers 2 is too large relative to the depth of sinker 2, making it difficult to form an effective structural reinforcement area between two adjacent sinkers 2, and the strength enhancement is not obvious.

[0087] Therefore, by limiting g1 / t to a value between 0.5 and 10, and g1 to a value between 0.5 mm and 20 mm, a reasonable spacing between two adjacent sinkers 2 is ensured. This not only ensures the smooth processing and forming of several sinkers 2, avoids cracking, and improves production yield, but also ensures that an effective structural reinforcement area can be formed between two adjacent sinkers 2, thereby ensuring the structural reinforcement effect on the cover plate body 1.

[0088] Optionally, the value of g1 / t is any one of 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or a value between any two values; the value of g1 is any one of 0.5 mm, 1 mm, 5 mm, 10 mm, 15 mm, 20 mm or a value between any two values.

[0089] Additionally, in other embodiments, such as Figures 10 to 13 As shown, the reinforcing structure is a convex hull 3, and the distance between two adjacent convex hulls 3 along the X direction and / or Y direction is g2, where 3 mm ≤ g2 ≤ 50 mm. It should be noted that two adjacent protrusions 3 refer to two protrusions 3 separated only by a portion of the cover plate body 1, without being separated by mounting through holes or other structures, and there are no mounting through holes between the two adjacent protrusions 3. For two adjacent protrusions 3 spaced apart along the X direction, g2 is the distance between the two adjacent protrusions 3 along the X direction; for two adjacent protrusions 3 spaced apart along the Y direction, g2 is the distance between the two adjacent protrusions 3 along the Y direction. The protrusions 3 are stamped from a portion of the cover plate body 1. If g2 is less than 3mm, the distance between the two adjacent protrusions 3 is too small, resulting in insufficient material flow space during the stamping process, causing mutual conflict and preventing the protrusions 3 from being formed smoothly. If g2 is greater than 50mm, the distance between the two adjacent protrusions 3 is too large, making it difficult to form an effective structural reinforcement area between the two adjacent protrusions 3. Furthermore, the distribution of the protrusions 3 on the cover plate body 1 is too sparse, resulting in an insignificant structural reinforcement effect on the cover plate body 1, and there is also the problem of insufficient arrangement space on the cover plate body 1.

[0090] Therefore, by limiting g2 to a value between 3 mm and 50 mm, a reasonable spacing between two adjacent convex humps 3 can be ensured. This can avoid interference between the two adjacent convex humps 3, ensure the smooth forming of the convex humps 3, and avoid the problem of insufficient arrangement space on the cover plate body 1. This can improve the structural reinforcement effect of the two adjacent convex humps 3 on the cover plate body 1, and ensure that the reinforcement structure can effectively improve the structural strength of the cover plate body 1.

[0091] Optionally, the value of g2 is any one of 3 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, or a value between any two of these values.

[0092] It should be noted that the cover plate body 1 has a first surface 111 and a second surface 112 arranged opposite to each other along the Z direction. The first surface 111 is adapted to face the inner cavity of the housing 6, and the second surface 112 is adapted to face the outside of the housing 6. After the cover plate body 1 is assembled with the housing 6, the second surface 112 is flush with the end face of the opening end of the housing 6. The outer side of the housing 6 is covered with insulating tape 8, and after the insulating tape 8 is covered on the outer side of the housing 6, it is bent toward the second surface 112 of the cover plate body 1. The folded edge of the insulating tape 8 covers at least a part of the area of ​​the second surface 112. A top patch 7 is also attached to the second surface 112. The top patch 7 is bonded to the second surface 112 and overlaps the folded edge of the insulating tape 8.

[0093] In one embodiment, the edge distance between the reinforcing structure and the edge of the cover body 1 along the X and / or Y directions is E, where 2 mm ≤ E ≤ 30 mm. The cover body 1 has two first side edges 110 arranged opposite each other along the Y direction and two second side edges 120 arranged opposite each other along the X direction, further combined with Figures 5 to 6 As shown, for the reinforcing structure adjacent to the first side 110, E refers to the distance along the Y direction between the reinforcing structure and the first side 110 of the cover plate body 1; for the reinforcing structure adjacent to the second side 120, E refers to the distance along the X direction between the reinforcing structure and the second side 120 of the cover plate body 1 (not shown in the figure); since the edge of the insulating tape 8 is wrapped around the area between the reinforcing structure and the edge of the cover plate body 1, if E is less than 2 mm, the reinforcing structure is too close to the edge of the cover plate body 1, resulting in a small adhesive bonding area of ​​the edge of the insulating tape 8 on the second surface 112, making it easy to lift off. Furthermore, the effective bonding area of ​​the top patch 7 on the edge of the insulating tape 8 is too small, also making it easy to lift off, resulting in poor insulation performance of the battery cell and causing customer dissatisfaction; if E is greater than 30 mm... If E is too large, the reinforcing structure is too far from the edge of the cover plate body 1, and the structural reinforcement effect on the edge of the cover plate body 1 is not obvious. In addition, the reinforcing structure is either a groove 2 or a convex 3. When the reinforcing structure is a groove 2, the top patch 7 is bonded to the area on the second surface 112 where the groove 2 is not provided, and overlaps on the folded edge of the insulating tape 8. If E is too large, the effective bonding area of ​​the adhesive backing of the top patch 7 will be reduced, and the bonding strength will be insufficient and it will be easy to lift off. When the reinforcing structure is a convex 3, if E is too large, it will also make it more difficult to attach the top patch 7. It is necessary to make a contour design according to the convex 3, which is more complicated and costly.

[0094] Therefore, by limiting E to a value within the range of 2 mm to 30 mm, it is possible to ensure that sufficient bonding area is reserved on the surface of the cover plate body 1 for the insulating tape 8. Consequently, the folded edge of the insulating tape 8 can provide sufficient bonding area for the top patch 7, thereby preventing the insulating tape 8 from lifting and the top patch 7 from lifting. This ensures the insulation of the outer side of the battery cell, improves customer satisfaction, and also prevents the reinforcing structure from being too far from the edge of the cover plate body 1, which would result in an insignificant reinforcing effect. This ensures that the reinforcing structure can effectively enhance the structural strength of the cover plate body 1 and that the surface of the cover plate body 1 can provide sufficient bonding area for the top patch 7, further preventing the top patch 7 from lifting and reducing the bonding difficulty of the top patch 7, improving efficiency and reducing costs.

[0095] The following experiments verify the influence of different parameter values ​​on the structural strength of the cover plate. The parameter settings and corresponding verification results of the embodiments and comparative examples are shown in Table 1.

[0096] Table 1

[0097]

[0098] As can be seen from Table 1, for the cover plate structures of Examples 1 to 4, all parameters are within the range defined in this application, the reinforcing structure can be successfully processed and formed, the cover plate body 1 does not fail, and the structural strength of the cover plate body 1 is strengthened.

[0099] For the cover plate structure of Comparative Example 1, the t / T value is 0.42, which is greater than 0.4 and exceeds the upper limit, falling outside the range defined in this application. For the cover plate structure of Comparative Example 2, the L1 / W1 value is 4.1, which is greater than 4 and exceeds the upper limit, falling outside the range defined in this application. For the cover plate structure of Comparative Example 3, the g1 / t value is 10.2, which is greater than 10 and exceeds the upper limit, falling outside the range defined in this application. Comparing the strength of the cover plate body 1 of Comparative Examples 1 to 3 with that of a cover plate body of the same thickness without reinforcement, the strength is slightly lower. This indicates that the reinforcement structure designed according to the parameters of Comparative Examples 1 to 3 cannot effectively enhance the structural strength of the cover plate body 1; instead, it makes the cover plate body 1 weaker.

[0100] For the cover plate structure of Comparative Example 4, the value of g1 / t is 0.4, which is less than 0.5. g1 / t is below the lower limit and is not within the range defined in this application. After the cover plate body is stamped, the reinforcing structure has defects in its forming. There are cracks between two adjacent reinforcing structures. That is, the reinforcing structure cannot be formed smoothly, and thus cannot effectively strengthen the structural reinforcement of the cover plate body 1.

[0101] In summary, when the cover plate structure adopts the parameter range defined in this application, the smooth processing and forming of the reinforcing structure can be guaranteed, and the production yield of the cover plate structure can be guaranteed, which is conducive to improving the structural strength of the cover plate body 1 through the reinforcing structure.

[0102] The cover plate structure in this embodiment strengthens the cover plate structure by setting a groove 2 or a protrusion 3 as a reinforcing structure in the cover plate body 1, thereby reducing the thickness of the cover plate body 1, achieving lightweighting and reducing material costs, while ensuring the reliability of the reinforcing structure in strengthening the cover plate body 1 structure and improving production yield.

[0103] According to an embodiment of the present invention, another aspect provides a cover plate assembly, including: the aforementioned cover plate structure and the pole post 4. The mounting through hole in the cover plate structure includes a pole post hole; the pole post 4 passes through the pole post hole. Since the cover plate assembly includes the cover plate structure and has the same effects as the cover plate structure, it will not be described further here.

[0104] In one embodiment, the cover plate assembly further includes: an explosion-proof valve 5, a first plastic part, a second plastic part, and a sealing ring. The mounting through hole also includes an explosion-proof valve hole, in which the explosion-proof valve 5 is installed; the first plastic part is disposed on the side of the cover plate body 1 away from the inner cavity of the housing 6 and located between the pole post 4 and the cover plate body 1 to ensure insulation between the pole post 4 and the cover plate body 1; the second plastic part is disposed on the side of the cover plate body 1 facing the inner cavity to ensure insulation between the cover plate body 1 and the pole group; the sealing ring is sleeved on the outer periphery of the pole post 4 and located between the pole post 4 and the hole wall of the pole post hole 101 to ensure sealing between the pole post 4 and the cover plate body 1.

[0105] According to an embodiment of the present invention, another aspect provides a battery cell, comprising: a housing 6, an electrode assembly, and the aforementioned cover plate assembly. The housing 6 has an open end; the electrode assembly is disposed within the inner cavity of the housing 6; the cover plate assembly covers the open end of the housing 6. The electrode post 4 in the cover plate assembly is electrically connected to the electrode tab on the electrode assembly. Since the battery cell includes the cover plate assembly, it has the same effects as the cover plate assembly, and will not be described further here.

[0106] Optionally, the battery cell is a lithium-ion battery cell.

[0107] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cover plate structure, characterized in that, include: The cover plate body has multiple mounting through holes, and the thickness of the cover plate body along the Z direction is T; A plurality of reinforcing structures are constructed on the cover plate body, the plurality of reinforcing structures are spaced apart from each other, and the reinforcing structures are spaced apart from the mounting through holes, the reinforcing structures being recessed grooves; The reinforcing structure is arranged globally on the cover plate body, except for the mounting through holes; The sinkhole is formed by a recess in at least a portion of the surface of the cover plate body along the Z direction, and the depth of the sinkhole along the Z direction is t, and t and T satisfy the relationship: 0 < t / T ≤ 0.4; The reinforcing structure is a sinkhole and the shape of the reinforcing structure is rectangular. The cover plate body has two first side edges arranged opposite to each other along the Y direction and two second side edges arranged opposite to each other along the X direction. The settling groove includes a first rectangular groove, which is disposed between the mounting through hole and the first side and between two adjacent mounting through holes; the first rectangular groove has two first long sides arranged opposite each other along the Y direction and two first wide sides arranged opposite each other along the X direction, the first long side has a dimension L1 along the X direction and the first wide side has a dimension W1 along the Y direction, wherein L1≥W1 and 1≤L1 / W1≤4; The settling groove includes a second rectangular groove, which is disposed between the mounting through hole and the second side and between two adjacent mounting through holes; the second rectangular groove has two second long sides arranged opposite each other along the X direction and two second wide sides arranged opposite each other along the Y direction, the dimension of the second long side along the Y direction is L2, and the dimension of the second wide side along the X direction is W2, wherein L2≥W2, and 1≤L2 / W2≤4; The range of L1 is 0.5 mm ≤ L1 ≤ 40 mm, the range of W1 is 0.5 mm ≤ W1 ≤ 40 mm, the range of L2 is 0.5 mm ≤ L2 ≤ 40 mm, and the range of W2 is 0.5 mm ≤ W2 ≤ 40 mm.

2. The cover plate structure according to claim 1, characterized in that, The thickness T of the cover plate body along the Z direction ranges from 0.5 mm to 10 mm. And / or, the depth t of the settling tank along the Z direction is in the range of: 0 < t ≤ 4 mm.

3. The cover plate structure according to claim 1, characterized in that, The reinforcing structure is a sinking trough, and the distance between two adjacent sinking troughs along the X and / or Y directions is g1. g1 and t satisfy the following relationship: 0.5≤g1 / t≤10, 0.5mm≤g1≤20 mm.

4. The cover plate structure according to any one of claims 1 to 3, characterized in that, The distance between the reinforcing structure and the edge of the cover plate body along the X and / or Y directions is E, where 2 mm ≤ E ≤ 30 mm.

5. A cover plate assembly, characterized in that, include: The cover plate structure according to any one of claims 1 to 4, wherein the mounting through hole in the cover plate structure includes a pole hole; The pole is inserted into the pole hole.

6. A battery cell, characterized in that, include: The shell has an open end; The electrode assembly is disposed within the inner cavity of the housing; The cover plate assembly of claim 5 is disposed over the opening end of the housing.

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