Cover plate arrangement and battery

Abstract

Cover plate arrangement, characterized in that it comprises: a cover plate having a fixing hole arranged to penetrate the cover plate along the thickness direction thereof; a pressure plate arranged on the outside of the cover plate; a terminal post that is inserted into the mounting hole, and wherein the pressure plate is slid onto the terminal post; and wherein the terminal post comprises: a flange edge portion configured for electrical connection to an output end of a cell; wherein the flange edge portion is disposed on the inside of the cover plate, and the projection of the flange edge portion on the plane in which the cover plate is located at least partially overlaps the projection of the pressure plate on the plane in which the cover plate is located; and the width of the pressure plate is “W1”, the thickness of the pressure plate is “t1”, the width of the flange edge section is “W2” and the thickness of the flange edge section is “t2”, where the above parameters then satisfy: 0.5 ≤ W 1 × t 1 W 2 × t 2 ≤ 11, where the width “W1” of the pressure plate is the shortest distance from the inner edge of the pressure plate to the outer edge of the pressure plate, and the width “W2” of the flange edge section is the shortest distance from the inner edge of the flange edge section to the outer edge of the flange edge section.

Description

TECHNICAL FIELD

[0001] The present invention relates to the technical field of power batteries and, in particular, to a cover plate assembly and a battery. BACKGROUND

[0002] A power battery is a battery that provides a power source for tools and generally consists of a metal casing, a cell housed within the metal casing, and a cover plate assembly mounted on top of the metal casing. A terminal post structure is located within the cover plate assembly, which acts as a power transmission element for the power battery. Therefore, the stability of the terminal post structure itself influences the performance of the power battery.

[0003] Currently, the conventional cover plate assembly generally includes a cover plate, a pressure plate, and a terminal post. The terminal post is inserted onto the cover plate and welded and fixed to the cell's tab to establish the electrical connection between the terminal post and the cell. The pressure plate is slid onto the terminal post and pressed onto the cover plate. The pressure plate is welded and fixed to the terminal post to establish a firm connection between the terminal post and the cover plate.

[0004] During use of the power battery, the terminal post is easily pulled by the cell or by external forces, resulting in deformation of the terminal posts or failure of the weld between the terminal post and the pressure plate. In response to this problem, the conventional cover plate assembly often increases the dimension of the pressure plate or the terminal posts to reinforce the structural strength of the two components. However, increasing the dimension of the pressure plate correspondingly increases the load borne by the cover plate, which increases the risk of cover plate deformation. In addition, increasing the dimension of the terminal posts occupies the space in the cell, affecting the space utilization rate within the cell. SUMMARY OF THE INVENTION

[0005] The object of the present invention is to provide a cover plate assembly and a battery that balances the overall structure of the cover plate assembly by adjusting the pressure plate and the flange edge portion of the terminal posts to solve the problem of insufficient matching between the existing pressure plate and the terminal posts.

[0006] To achieve the above object, the present invention provides the following technical solutions: A cover plate assembly comprising: a cover plate having a fixing hole arranged to penetrate the cover plate along the thickness direction thereof; a pressure plate arranged on the outside of the cover plate; a terminal post which is inserted into the mounting hole, and wherein the pressure plate is pushed onto the terminal post; and wherein the terminal post comprises: a flange edge portion configured for electrical connection to an output end of a cell; wherein the flange edge portion is disposed on the inside of the cover plate, and the projection of the flange edge portion on the plane in which the cover plate is located at least partially overlaps the projection of the pressure plate on the plane in which the cover plate is located; and the width of the pressure plate is “W1”, the thickness of the pressure plate is “t1”, the width of the flange edge section is “W2” and the thickness of the flange edge section is “t2”, where the above parameters then satisfy: 0.5≤W3×t1W2×t2≤11, where the width “W1” of the pressure plate is the shortest distance from the inner edge of the pressure plate to the outer edge of the pressure plate, and the width “W2” of the flange edge section is the shortest distance from the inner edge of the flange edge section to the outer edge of the flange edge section.

[0007] In some embodiments, the width of the pressure plate is “W1”, the thickness of the pressure plate is “t1”, the width of the flange edge portion is “W2”, and the thickness of the flange edge portion is “t2”, wherein the above parameters then satisfy: t1>t2, W2>W1.

[0008] In some embodiments, the width of the printing plate is “W1” and satisfies: 2≤Wi≤4mm.

[0009] In some embodiments, the width of the flange edge portion is “W2” and satisfies: 2≤W2≤5mm.

[0010] In some embodiments, the thickness of the printing plate is “t1” and satisfies: 1.5≤ti≤3mm.

[0011] In some embodiments, the thickness of the flange edge portion is “t2” and satisfies: 0.5≤t2≤1.5mm.

[0012] In some embodiments, an insulating element is further included, wherein the insulating element is slid onto the terminal post and arranged between the pressure plate and the cover plate to separate the pressure plate from the cover plate; and the Rockwell hardness of the insulating element is “K” and the Rockwell hardness “K” of the insulating element satisfies: 40≤K≤120.

[0013] In some embodiments, a sealing element is further included, wherein the sealing element is pushed onto the terminal post, and wherein the sealing element is arranged on the inside of the cover plate and arranged between the cover plate and the flange edge portion, and the projection of the sealing element on the plane in which the cover plate is located overlaps the projection of the insulating element on the plane in which the cover plate is located.

[0014] In some embodiments, the cover plate has a groove disposed around the mounting hole, and the insulating element is at least partially disposed in the groove; and the thickness of the insulating element is “t3”, the thickness of the sealing element is “t4” and the above parameters are met: 0.8≤t1+t3t2+t4≤4.

[0015] In some embodiments, the pressure plate is welded and fixed to the outer peripheral side of the terminal post so that a weld mark is formed between the pressure plate and the terminal post; and the width of the welding mark is “W3”, the height of the welding mark is “h” and the compression rate of the sealing element is “W”, and the above parameters meet: 0.6≤W3×hW≤20.

[0016] In some embodiments, the width of the sealing element is “W4” and the above parameters satisfy: 0.4≤W4W2≤2.5.

[0017] In some embodiments, the thickness of the cover plate is “t5” and the above parameters are met: 0.5≤t1t5≤3.

[0018] Based on the cover plate assembly described above, the present application further provides a battery comprising a cell and any of the cover plate assemblies described above, and the output end of the cell is electrically connected to the terminal post.

[0019] In some embodiments, the end surface of the terminal posts facing the outside of the cover plate is connected to a conductive bus bar.

[0020] In some embodiments, the flange edge portion is welded and fixed to the output end of the cell, and the welding area between the flange edge portion and the output end of the cell is “S1”, and the welding area between the terminal post and the conductive busbar is “S2”, and then satisfy the above parameters: 0.1≤S1S5≤7.

[0021] In some embodiments, the welding area “S I “ between the flange edge section and the outlet end of the cell: 78≤S1≤706mm 2 .

[0022] The cover plate assembly and the battery according to the embodiment of the present invention have the following advantageous effects over the prior art: In the terminal post of the cover plate assembly of the present application, the terminal post is connected and fixed to the cover plate through the cooperation between the pressure plate and the flange edge portion. The pressure plate is slid onto the terminal post on the outer side of the cover plate and welded and fixed to the terminal post. By controlling the specifications of the pressure plate and the flange edge portion, the pressure plate and the flange edge portion are matched to prevent the formation of structural weak points in the cover plate assembly. Furthermore, this ensures that there is sufficient welding space between the pressure plate and the terminal post, thereby ensuring the connection strength between the pressure plate and the terminal post.In addition, the flange edge portion can be avoided from excessively occupying the internal space of the battery, thereby ensuring the space utilization rate of the cell.

[0023] In addition, the cover plate assembly of the present application balances the overall structure of the cover plate assembly by controlling the specifications of the insulating members and the sealing member, which can prevent the overall structure of the cover plate assembly from being unbalanced and causing failure or cracking of the structure of the cover plate assembly. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of the cover plate assembly according to an embodiment of the present application; Fig. 2 is a schematic partial cross-sectional diagram of the cover plate assembly according to an embodiment of the present application; Fig.3 is a schematic partial cross-sectional diagram of the cover plate assembly according to an embodiment of the present application; Fig. 4 is an enlarged view of part “A” in Fig. 3; Fig. 5 is a schematic diagram of the cover plate according to an embodiment of the present application; Fig. 6 is a schematic diagram of the terminal posts according to an embodiment of the present application.

[0024] In the figures: 100. Cover plate arrangement; 1. Cover plate; 10. Groove; 2. Terminal post; 20. Body section; 21. Flange edge section; 3. Pressure plate; 4. Insulating element; 5. Welding mark; 6. Sealing element; 7. Mounting hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Specific embodiments of the present invention will be described in more detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0026] In describing the present invention, it is to be understood that when an element is referred to as being "attached to" or "disposed on" another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected" to another element, it may be directly connected to the other element or indirectly connected to the other element. The terms "installed," "connected," and "connected" are to be understood in a broad sense, e.g., it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection via an intermediate medium; it may be the internal connection of two elements or the interactive relationship of two elements.Those of ordinary skill in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0027] In describing the present invention, it should be noted that the terms "height", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inside", "outside", and the like used in the present invention to refer to the orientation or positional relationship are based on the orientation or positional relationship in the drawings and are only for the convenience of describing the present invention and simplifying the description and do not indicate or imply that the device or element referred to must have a particular orientation or must be constructed and operated in a particular orientation and thus should not be construed as limiting the present invention.

[0028] In describing the present invention, it should be understood that the terms "first" and "second" used in the present invention are used for descriptive purposes only and should not be understood to indicate a relative importance or implicitly indicate the number of specified technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Examples

[0029] As in the Fig.1-6, one embodiment of the present application provides a cover plate assembly 100 suitable for power batteries. The cover plate assembly 100 includes a cover plate 1, a terminal post 2, and a pressure plate 3. The cover plate 1 has a mounting hole 7 arranged to penetrate the cover plate along the thickness direction thereof. The terminal post 2 is inserted into the mounting hole 7 so that a portion of the terminal post 2 passes through the mounting hole 7 and extends to the outside of the cover plate 1. The pressure plate 3 is arranged on the outside of the cover plate 1 and slid onto the terminal post 2.

[0030] It should be noted that the side of the cover plate 1 facing the cell is the inside of the cover plate 1, and the side opposite the inside of the cover plate 1 is the outside of the cover plate 1.

[0031] The terminal post 2 has a body portion 20 and a flange edge portion 21. The body portion 20 is a cylindrical structure and is arranged along the thickness direction of the cover plate 1 such that the body portion 20 passes through the mounting hole 7 and extends to the outside of the cover plate 1; the flange edge portion 21 is formed on the cell-facing side of the body portion 20 and extends to the outside of the body portion 20. In this way, the flange edge portion 21 is arranged on the inside of the cover plate 1, and the projection of the flange edge portion 21 on the plane in which the cover plate 1 is located at least partially overlaps the projection of the pressure plate 3 on the plane in which the cover plate 1 is located.

[0032] It is understood that the pressure plate 3 is slid onto the terminal post 2 and welded to the terminal post 2, forming a weld mark 5 between the pressure plate 3 and the terminal post 2. In this way, the pressure plate 3 can generally conform to the outer peripheral surface of the body portion 20. Thus, when the flange edge portion 21 extends from the body portion 20 to the outside, the projections of the flange edge portion 21 and the pressure plate 3 at least partially overlap on the same plane.Taking the horizontal placement of the cover plate 1 as an example, in this case, the plane in which the cover plate 1 is located is a horizontal plane, and the projection of the flange edge portion 21 on the horizontal plane starts from the body portion 20 and extends to the outside of the body portion 20. Similarly, since the pressure plate 3 generally fits on the outer peripheral surface of the body portion 20, the projection of the pressure plate 3 on the horizontal plane also starts from the body portion 20 and extends to the outside of the body portion 20. Thus, according to the width specifications of the flange edge portion 21 and the pressure plate 3, it is possible for there to be a partial overlap between the projections of the flange edge portion 21 and the pressure plate 3 on the horizontal plane. For example, the width of the flange edge portion 21 is less than or equal to the width of the pressure plate 3.In this case, the projection of the flange edge portion 21 on the horizontal plane completely coincides with the projection of the pressure plate 3 on the horizontal plane, and the projection of the flange edge portion 21 and the pressure plate 3 on the horizontal plane completely overlap; the width of the flange edge portion 21 is larger than the width of the pressure plate 3. In this case, the projection area of ​​the flange edge portion 21 on the horizontal plane is larger than the projection area of ​​the pressure plate 3 on the horizontal plane, and the projection of the flange edge portion 21 and the pressure plate 3 on the horizontal plane partially overlap.

[0033] It is understood that the terminal post 2 of the cover plate assembly 100 is connected and fixed to the cover plate 1 by the cooperation between the pressure plate 3 and the flange edge portion 21, so that the dimensional specifications of the pressure plate 3 and the flange edge portion 21 affect the structural stability of the cover plate assembly 100.

[0034] For example, consider the case where the pressure plate 3 and the terminal post 2 are connected and fixed by welding. If the volume of the pressure plate 3 is too small, it is difficult to ensure the connection strength between the pressure plate 3 and the terminal post 2, which can easily lead to the failure of the connection between the pressure plate 3 and the terminal post 2. In addition, if the volume of the pressure plate 3 is too small, it can easily lead to laser degradation of the pressure plate 3 during welding and damage other structures. The larger the volume of the pressure plate 3, the larger the contact area between the pressure plate 3 and the terminal post 2, which is more conducive to ensuring the welding area between the pressure plate 3 and the terminal post 2, thereby ensuring the connection strength between the pressure plate 3 and the terminal post 2.However, if the volume of the pressure plate 3 is too large, the load carried by the cover plate 1 will be larger, and the cover plate 1 will be more likely to deform and cause structural failure.

[0035] Considering the case where the flange edge portion 21 is located on the inner side of the cover plate 1, it will occupy the space inside the cell. The smaller the volume of the flange edge portion 21, the smaller the volume of the internal space occupied by the flange edge portion 21, and the easier it is to improve the internal space utilization rate of the cell. However, the smaller the volume of the flange edge portion 21, the more likely the structural strength of the flange edge portion 21 is to be insufficient, and the flange edge portion 21 is easily deformed, resulting in failure of the connection between the terminal post 2 and the cell.

[0036] Therefore, the specifications of the pressure plate 3 and the flange edge portion 21 must match to balance the volumes of the two components and avoid the formation of structural weak points and failure of the cover plate assembly 100. Generally, the volume of the pressure plate 3 and the flange edge portion 21 can be controlled by their respective widths and thicknesses. The width of the pressure plate 3 is "W1," the thickness of the pressure plate 3 is "t1," the width of the flange edge portion 21 is "W2," and the thickness of the flange edge portion 21 is "t2," where the above parameters then satisfy: 0.5≤W1×t1W2×t2≤11

[0037] In the present embodiment, the width “W1” of the pressure plate 3 is the shortest distance from the inner edge of the pressure ring 3 to its outer edge, and the width “W2” of the flange edge portion 21 is the shortest distance from the inner edge of the flange edge portion 21 to its outer edge.

[0038] The value of W1×t1W2×t2 can be 0.5, 0.8, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0 or 11.0.

[0039] In order to verify that when the structural parameters of the cover plate assembly 100 arranged according to the present embodiment satisfy the above relationship, that is, when the width "W1" of the pressure plate 3, the thickness "t1" of the pressure plate 3, the width "W2" of the flange edge portion 21, and the thickness "t2" of the flange edge portion 21 can match, the cover plate assembly 100 of the present embodiment can avoid the generation of structural weak points compared to other cover plate assemblies, 10 groups of tests were conducted, see the following Table 1: In Table 1, Test Examples 1 to 10 are experiments based on the structure of the cover plate assembly 100 of the present embodiment, that is, the cover plate assembly 100 of Test Examples 1 to 10, wherein the width "W1" of the pressure plate 3, the thickness "t1" of the pressure plate 3, the width "W2" of the flange edge portion 21, and the thickness "t2" of the flange edge portion 21 satisfy the above matching relationship. Comparative Examples 1 to 2 are other structures of a cover plate assembly, that is, the width "W1" of the pressure plate 3, the thickness "t1" of the pressure plate 3, the width "W2" of the flange edge portion 21, and the thickness "t2" of the flange edge portion 21 of Comparative Examples 1 to 2 do not satisfy the above matching relationship.

[0040] The tensile force test procedure is as follows: 20 batteries are used for each test group. A tensile force block is mounted on the surface of the terminal post 2, and the tensile force block is connected to the tensile force sensor (DNS-2). After the pressure plate 3 is fixed, the tensile force sensor pulls the terminal post 2 through the tensile force block. The tensile force sensor (sensor model CLY30) is activated to record the tensile force value of the tensile force block until the terminal post 2 falls. The maximum value is read from the tensile force curve. The maximum value in the tensile force curve is above 1200, which is determined to be qualified.

[0041] The leak rate testing procedure is as follows: 20 batteries are used for each test group. Terminal post 2 is placed in a special hermetic detection tool, and then the hermetic detection tool is connected to the NHJ400 helium detector. Helium is introduced into the hermetic detection tool to observe whether the helium detector's leak rate value exceeds the standard. If the helium detector detects a leak, it is classified as unqualified. Table 1 w1 t1 w2 t2 W1×t1W2×t2 Tensile force value (N) Leakage rate Test example 1 2,1 1,5 4,4 1,5 0,5 1200 0 Test example 2 2,5 2,1 5,2 0,5 2,0 1500 0 Test example 3 2,8 2,2 2,2 0,5 5,6 1630 0 Test example 4 4 2,9 2,1 0,5 11,0 2000 0 Test example 5 3,2 3,0 1,5 0,75 8,5 1910 0 Test example 6 2,1 1,5 2,5 1,5 0,8 1320 0 Test example 7 3,2 2,1 2,1 0,5 6,4 1800 0 Test example 8 3,9 3,0 2,8 0,6 7,0 1850 0 Comparison example 1 2,0 1,5 5 1,5 0,4 950 0 Comparison example 2 4,0 3,0 2 0,5 12,0 2380 80%

[0042] As can be seen from Table 1, when the width "W1" of the pressure plate 3, the thickness "t1" of the pressure plate 3, the width "W2" of the flange edge portion 21, and the thickness "t2" of the flange edge portion 21 satisfy the above matching relationship, the cover plate assembly 100 does not have a structural weakness, and the terminal post 2 of the cover plate assembly 100 can withstand a tensile force of more than 1200 kN and ensure no air leakage. If the width "W1" of the pressure plate 3, the thickness "t1" of the pressure plate 3, the width "W2" of the flange edge portion 21, and the thickness "t2" of the flange edge portion 21 do not satisfy the above matching relationship, the corresponding cover plate assembly has a structural weakness, resulting in this type of cover plate assembly having the problem that the terminal post 2 cannot withstand sufficient tensile force or has insufficient airtightness.

[0043] Considering the welding method of the pressure plate 3 and the terminal posts 2, the thickness "t1" of the pressure plate 3 is usually larger than the thickness "t2" of the flange edge portion 21, that is, t1>t2. To prevent the pressure plate 3 from being too thick and the flange edge portion 21 from being too thin, which may cause the overall structure of the cover plate assembly 100 to be unbalanced, the width "W2" of the flange edge portion 21 may be larger than the width "W1" of the pressure plate 3, that is, W2>W1, so that the volumes of the two components are as balanced as possible and the cover plate assembly 100 is prevented from forming a structural weak point. Of course, as an example of the present embodiment, the width "W1" of the pressure plate may also satisfy the following: 2≤Wi≤4mm.For example, the width "W1" of the printing plate 3 may be 2 mm, 3 mm, or 4 mm to prevent the width "W1" of the printing plate 3 from being too large to cause warping and unevenness of the printing plate 3. Alternatively, by controlling the thickness "t1" of the printing plate 3, the dimension of the printing plate 3 can also be controlled within a suitable range. As an example, for the present embodiment, for example, the thickness "t1" of the printing plate 3 satisfies: 1.5≤t1≤3mm. For example, the thickness "t1" of the printing plate 3 may be 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, or 3 mm.

[0044] In addition, the specification of the flange edge portion 21 and the specification of the pressure plate 3 must match, and the dimension of the flange edge portion 21 must also be controlled within a certain range. For example, as an example of the present embodiment, the width "W2" of the flange edge portion 21 satisfies: 2≤W2≤5mm. For example, the width "W2" of the flange edge portion 21 can be 2mm, 3mm, 4mm, or 5mm. Alternatively, the specifications of the flange edge portion 21 are controlled by controlling the thickness "t2" of the flange edge portion 21. As an example of the present embodiment, the thickness "t2" of the flange edge portion 21 satisfies: 0.5≤t2≤1.5mm. For example, the thickness “t2” of the flange edge portion 21 may be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm or 1.5 mm.

[0045] In addition, the thickness of the cover plate 1 affects the structural strength of the cover plate 1 itself and also affects the overall structural balance of the cover plate assembly 100. If the thickness of the cover plate 1 is too small, deformation of the cover plate 1 is likely to occur. Therefore, the thickness "t5" of the cover plate 1 and the thickness "t1" of the pressure plate 3 should also match to avoid the formation of structural weak points in the cover plate assembly 100. As an example, for the present embodiment, the above parameters can satisfy: 0.5≤t1t5≤3

[0046] Generally, the thickness "t5" of the cover plate 1 can satisfy the following: 1≤t5≤3 mm, so that the cover plate 1 can have sufficient structural strength and avoid the cover plate 1 occupying too much space. For example, the thickness "t5" of the cover plate 1 can be 1 mm, 2 mm, or 3 mm.

[0047] With reference to the Fig. 1-6, as an example of the present embodiment, the cover plate assembly 100 also includes an insulating member 4 slid onto the terminal post 2 and disposed between the pressure plate 3 and the cover plate 1 to separate the pressure plate 3 from the cover plate 1. The insulating member 4 forms a buffer between the pressure plate 3 and the cover plate 1. In this way, when the terminal post 2 is subjected to a tensile force toward the interior of the cell, the insulating member 4 can provide a buffer for the weld between the pressure plate 3 and the terminal post 2 to prevent the weld between the pressure plate 3 and the terminal post 2 from cracking due to repeated impact.

[0048] It is understood that when the terminal post 2 is subjected to a tensile force toward the inside of the cell, the terminal post 2 tends to move toward the inside of the cell. Under the confinement of the cell, the displacement of the terminal post 2 in the thickness direction of the cover plate 1 is very small. However, since the pressure plate 3 is welded and fixed to the terminal post 2, the pressure plate 3 is driven by the terminal post 2 to compress the insulating member 4. If the deformation of the insulating member 4 due to extrusion is large, this will cause uneven displacement of the pressure plate 3 and the terminal post 2, and then cause a force along the thickness direction of the cover plate 1 to act on the weld part between the pressure plate 3 and the terminal post 2, that is, the weld mark 5. To avoid this situation, it is possible to consider controlling the hardness of the insulating member 4.For example, if the Rockwell hardness of the insulating member 4 is "K", the Rockwell hardness "K" of the insulating member 4 satisfies: 40≤K≤120. For example, the Rockwell hardness "K" of the insulating member 4 can be 40, 50, 60, 70, 80, 90, 100, 110, or 120 to control the deformation of the insulating member 4 due to extrusion and prevent breakage and failure of the weld mark 5.

[0049] With reference to the Fig. 1-6, as an example of the present embodiment, the cover plate assembly 100 may further comprise a sealing element 6 slid onto the terminal post 2. The sealing element 6 is arranged on the inside of the cover plate 1 and is located between the cover plate 1 and the flange edge portion 21. In addition, the projection of the sealing element 6 on the plane in which the cover plate 1 is located overlaps the projection of the insulating element 4 on the plane in which the cover plate 1 is located.

[0050] It should be understood that since the insulating member 4 and the sealing member 6 are both slid onto the terminal post 2, the projections of the insulating member 4 and the sealing member 6 on the plane in which the cover plate 1 is located both start at the body portion 20 and extend to the outside of the body portion 20. Therefore, by controlling the length of the sealing member 6 extending from the body portion 20 and the length of the insulating member 4 extending from the body portion 20, the projection of the sealing member 6 on the plane in which the cover plate 1 is located can be designed to overlap the projection of the insulating member 4 on the plane in which the cover plate 1 is located.That is, the projection of the insulating member 4 on the cover plate 1 can cover the projection of the sealing member 6 on the cover plate 1, so that the insulating member 4 and the sealing member 6 can cooperate with each other, resulting in better sealing and insulating effects of the cover plate assembly 100.

[0051] Referring to the Fig.1-6, as an example of the present embodiment, the cover plate 1 has a groove 10 arranged around the mounting hole 7, and the insulating member 4 is at least partially arranged in the groove 10. The insulating member 4 can adopt various structures. Part of the insulating member 4 is arranged in the groove 10, that is, the pressure plate 3 and the cover plate 1 can be separated, and the remaining part of the insulating member 4 can be adjusted according to product requirements, such as wrapping the insulating member 4 around the pressure plate 3 to provide installation positioning for the pressure plate 3. By providing the insulating member 4 and the sealing member 6, the outer side of the cover plate 1 is arranged with the pressure plate 3 and the insulating member 4, and the inner side of the cover plate 1 is arranged with the sealing member 6 and the flange edge portion 21.The inner and outer sides of the cover plate 1 are clamped together by these components, forming a seal around the terminal post 2. To ensure that the cover plate assembly 100 is structurally balanced in its thickness direction, the components located on the inner side of the cover plate 1 and the components located on the outer side of the cover plate 1 must naturally constrain each other in the thickness direction of the cover plate 1. For example, if the thickness of the insulating element 4 is "t3" and the thickness of the sealing element 6 is "t4", the above parameters satisfy: 0.8≤t1+t3t2+t4≤4

[0052] Generally, the thickness "t3" of the insulating member 4 can satisfy: 0.5≤t3≤1 mm, and the thickness "t4" of the sealing member 6 can satisfy: 0.5≤t4≤1 mm, so as to ensure that the insulating member 4 and the sealing member 6 do not occupy too much internal space of the cover plate assembly 100 and ensure the reasonable use of the space of the cover plate assembly 100. For example, the thickness "t3" of the insulating member 4 can be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1 mm, and the thickness "t4" of the sealing member 6 can be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1 mm.

[0053] It should be understood that during use of the power battery, the terminal post 2 may also be subjected to a tensile force toward the outside of the cover plate 1. In this case, the sealing member 6 is compressed due to the extrusion of the flange edge portion 21, so that the terminal post 2 tends to move toward the outside of the cover plate 1, thereby generating forces at the welding point between the terminal post 2 and the pressure plate 3, i.e., the weld mark 5, which can easily cause the weld mark 5 to crack and fail. Therefore, in addition to controlling the hardness of the insulating member 4, the welding area of ​​the weld mark 5 may also be controlled to ensure that the weld mark 5 itself has sufficient bonding strength.As an example of the present embodiment, the width of the weld mark 5 is “W3”, the height of the weld mark 5 is “h”, and the compression rate of the sealing member 6 is “W”, and the above parameters then satisfy:. 0.6≤W3×hW≤20

[0054] The width "W3" of the weld mark 5 can meet the following: 0.5≤W3≤2 mm to ensure that the welding area of ​​the weld mark 5 is sufficient. In addition, the compression rate W of the sealing element 6 can meet the following: 20%≤W≤45% to ensure that the sealing element 6 can withstand the force between the cover plate 1 and the flange edge portion 21. For example, the width “W3” of the welding mark 5 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2mm, and the compression rate “W” of the sealing element 6 can be one of 20%, 21%, 22%, 23%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44% and 45%.In addition, when the terminal post 2 is subjected to a tensile force toward the outside of the cover plate 1, the sealing member 6 is pressed against the inside of the cover plate 1 due to the extrusion of the flange edge portion 21, and the sealing member 6 generates a corresponding reaction force on the flange edge portion 21. Since the flange edge portion 21 and the outlet end of the cell are generally connected and fixed by welding, the flange edge portion 21 has a certain welding heat affected zone. If the contact area between the sealing member 6 and the flange edge portion 21 is too large, it is easy to cause the entire welding heat affected zone to be subjected to long-term stress, which then leads to fatigue cracking of the flange edge portion 21 corresponding to the welding heat affected zone.However, if the contact area between the sealing element 6 and the flange edge portion 21 is insufficient, the sealing effect is easily affected, resulting in the cover plate assembly 100 not sealing. Therefore, the contact area between the sealing element 6 and the flange edge portion 21 should also be controlled within a suitable range so that the structures of the sealing element 6 and the flange edge portion 21 match each other. As an example of the present embodiment, the width of the flange edge portion 21 is "W2" and the width of the sealing element 6 is "W4", and the above parameters are satisfied. 0.4≤W4W2≤2.5

[0055] The width "W4" of the sealing element 6 can satisfy the following: 2≤W4≤5mm, so that the sealing element 6 can be installed between the cover plate 1 and the flange edge portion 21 to cooperate with the cover plate 1 and the flange edge portion 21. For example, the width "W4" of the sealing element 6 can be 2 mm, 3 mm, 4 mm, or 5 mm.

[0056] Based on the cover plate assembly described above, the present application also provides a battery comprising a cell and any of the cover plate assemblies described above, and the output end of the cell is electrically connected to the terminal post 2. In addition, the end surface of the terminal posts 2 facing the outside of the cover plate 1 is connected to a conductive bus bar.

[0057] It should be understood that in the battery of the present embodiment, the cell, terminal post 2, and conductive bus bar are welded and fixed by welding the flange edge portion 21 to the cell output end and the terminal post 2 to the conductive bus bar, so that the cell, terminal post 2, and conductive bus bar form a current path. The connection area of ​​welding the flange edge portion 21 to the cell output end and the connection area of ​​welding the terminal posts 2 to the conductive bus bar are both the flow area of ​​the current path. Therefore, the connection area between the flange edge portion 21 and the cell output end and the connection area between the terminal post 2 and the conductive bus bar affect the uniformity of the current density of the terminal posts 2 in the current path.The connection area between the flange edge portion 21 and the cell output end and the connection area between the terminal post 2 and the conductive busbar are aligned, so there is no narrow part with a sudden increase in resistance in the current path, and the current density of the terminal posts 2 is more uniform, and excessive local heating due to increased resistance in a specific part does not occur. Furthermore, the connection area between the flange edge portion 21 and the cell output end and the connection area between the terminal post 2 and the conductive busbar are aligned, so the connection strength between the inside of the terminal posts 2 and the outside of the terminal posts 2 is more balanced, thereby improving the structural strength of the cover plate assembly 100.As an example of the present embodiment, the welding area between the flange edge portion 21 and the output end of the cell is “S1”, and the welding area between the terminal post 2 and the conductive bus bar is “S2”, and then satisfy the above parameters:. 0.1≤S1S5≤7

[0058] It should be noted that the welding area “S I" between the flange edge portion 21 and the cell exit end refers to the cross-sectional area of ​​the welding area between the flange edge portion 21 and the cell exit end, wherein the cross-section perpendicular to the thickness direction of the cover plate 1 is considered the cross-section. Analogously, the welding area "S2" between the terminal post 2 and the conductive busbar refers to the cross-sectional area of ​​the welding area between the terminal post 2 and the conductive busbar, wherein the cross-section perpendicular to the thickness direction of the cover plate 1 is considered the cross-section.

[0059] Of course, in a power battery, the weight of the cell is generally large, and the tensile force generated by the cell on the flange edge portion 21 is greater than the tensile force generated by the terminal post 2 on the pressure plate 3. Therefore, in addition to the connection area between the flange edge portion 21 and the output end of the cell and the connection area between the terminal post 2 and the conductive busbar, the welding area "S IThe welding area "S1" between the flange edge portion 21 and the cell output end, and the welding area "S2" between the terminal post 2 and the conductive busbar should be designed within an appropriate range to meet the stress relief requirements between the flange edge portion 21 and the cell output end, and between the terminal post 2 and the conductive busbar, to prevent connection failures between the flange edge portion 21 and the cell output end, and between the terminal post 2 and the conductive busbar. As an example of the present embodiment, the welding area "S1" between the flange edge portion 21 and the cell output end can satisfy: 78≤S1≤706 mm2, and the welding area S2 between the terminal post 2 and the conductive busbar can satisfy: 100≤S1≤800 mm2.For example, the welding area “S1” between the flange edge section 21 and the outlet end of the cell can have one of the dimensions 78mm. 2 , 79mm 2 , 80mm 2 , 90mm 2 , 95mm 2 , 100mm 2 , 105mm 2 , 110mm 2 , 115mm 2 , 120mm 2 , 125mm 2 , 130mm 2 , 140mm 2 , 150mm 2 , 160mm 2 , 170mm 2 , 180mm 2 , 190mm 2 , 200mm 2 , 210mm 2 , 220mm 2 , 230mm 2 , 240mm 2 , 250mm 2 , 260mm 2 , 270mm 2 , 280mm 2 , 290mm 2 , 300mm 2 , 310mm 2 , 320mm 2 , 330mm 2 , 340mm 2 , 350mm 2 , 360mm 2 , 370mm 2 , 380mm 2 , 390mm 2 , 400mm 2 , 410mm 2 , 420mm 2 , 430mm 2 , 440mm 2 , 450mm2 , 460mm 2 , 470mm 2 , 480mm 2 , 490mm 2 , 500mm 2 , 510mm 2 , 520mm 2 , 530mm 2 , 540mm 2 , 550mm 2 , 560mm 2 , 570mm 2 , 580mm 2 , 590mm 2 , 600mm 2 , 610mm 2 , 620mm 2 , 630mm 2 , 640mm 2 , 650mm 2 , 660mm 2 , 670mm 2 , 680mm 2 , 690mm 2 , 700mm 2 , 701mm 2 , 702mm 2 , 703mm 2 , 704mm 2 , 705mm 2 and 706mm 2 The welding area “S2” between the terminal post 2 and the conductive busbar can have one of the dimensions of 100mm 2 , 105mm 2 , 110mm 2 , 115mm 2 , 120mm 2 , 125mm 2 , 130mm 2 , 140mm 2 , 150mm 2 , 160mm 2 , 170mm 2 , 180mm 2, 190mm 2 , 200mm 2 , 210mm 2 , 220mm 2 , 230mm 2 , 240mm 2 , 250mm 2 , 260mm 2 , 270mm 2 , 280mm 2 , 290mm 2 , 300mm 2 , 310mm 2 , 320mm 2 , 330mm 2 , 340mm 2 , 350mm 2 , 360mm 2 , 370mm 2 , 380mm 2 , 390mm 2 , 400mm 2 , 410mm 2 , 420mm 2 , 430mm 2 , 440mm 2 , 450mm 2 , 460mm 2 , 470mm 2 , 480mm 2 , 490mm 2 , 500mm 2 , 510mm 2 , 520mm 2 , 530mm 2 , 540mm 2 , 550mm 2 , 560mm 2 , 570mm 2 , 580mm 2 , 590mm 2 , 600mm 2 , 610mm 2 , 620mm 2 , 630mm 2 , 640mm 2 , 650mm 2 , 660mm 2 , 670mm 2 , 680mm 2, 690mm 2 , 700mm 2 , 710mm 2 , 720mm 2 , 730mm 2 , 740mm 2 , 750mm 2 , 760mm 2 , 770mm 2 , 780mm 2 , 790mm 2 and 800mm 2 have.

[0060] In summary, in the terminal post 2 of the cover plate assembly 100 according to the embodiment of the present application, the terminal post 2 is connected and fixed to the cover plate 1 through the cooperation between the pressure plate 3 and the flange edge portion 21, and the pressure plate 3 is pushed onto the terminal post 2 on the outer side of the cover plate 1 and welded and fixed to the terminal post 2. By controlling the specifications of the pressure plate 3 and the flange edge portion 21, the pressure plate 3 and the flange edge portion 21 are matched to prevent the formation of structural weak points in the cover plate assembly 100. Furthermore, in this way, it can be ensured that there is sufficient welding space between the pressure plate 3 and the terminal post 2, thereby ensuring the connection strength between the pressure plate 3 and the terminal post 2.In addition, the flange edge portion 21 can be prevented from excessively occupying the internal space of the battery, thereby ensuring the space utilization rate of the cell.

[0061] Furthermore, the cover plate assembly 100 of the embodiment of the present application controls the specifications of the insulating member 4 and the sealing member 6 to balance the overall structure of the cover plate assembly 100, thereby preventing the overall structure of the cover plate assembly 100 from being unbalanced and the structure of the cover plate assembly 100 from being failed or torn.

[0062] The above is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and substitutions without departing from the technical principle of the present invention, and these improvements and substitutions should also be considered within the scope of the present invention.

Claims

[1] Cover plate arrangement, characterized by , that it exhibits the following: a cover plate having a fixing hole arranged so that it penetrates the cover plate along its thickness direction; a printing plate located on the outside of the cover plate; a terminal post which is inserted into the mounting hole, wherein the pressure plate is slid onto the terminal post; and wherein the terminal post comprises: a flange edge section designed for electrical connection to an output end of a cell; wherein the flange edge section is located on the inside of the cover plate, and the projection of the flange edge section on the plane in which the cover plate is located overlaps at least partially with the projection of the pressure plate on the plane in which the cover plate is located; and the width of the pressure plate “W1”, the thickness of the pressure plate “t1”, the width of the flange edge section “W2”, and the thickness of the flange edge section “t2”, satisfying the above parameters: 0.5≤W1×t1W2×t2≤11, where the width “W1” of the pressure plate is the shortest distance from the inner edge of the pressure plate to the outer edge of the pressure plate, and the width “W2” of the flange edge section is the shortest distance from the inner edge of the flange edge section to the outer edge of the flange edge section. [2] Cover plate arrangement according to claim 1, characterized by , that the width of the pressure plate is “W1”, the thickness of the pressure plate is “t1”, the width of the flange edge section is “W2”, and the thickness of the flange edge section is “t2”, where the above parameters then satisfy: t1>t2, W2>W1. [3] Cover plate arrangement according to claim 1 or 2, characterized by, that the width of the printing plate is “W1” and satisfies: 2≤W1≤4mm. [4] Cover plate arrangement according to one of the preceding claims, characterized by , that the width of the flange edge section “W2” is and meets: 2≤W2≤5mm. [5] Cover plate arrangement according to one of the preceding claims, characterized by , that the thickness of the printing plate “t1” is and satisfies: 1.5≤t1≤3mm. [6] Cover plate arrangement according to one of the preceding claims, characterized by , that the thickness of the flange edge section “t2” is and satisfies: 0.5≤t2≤1.5mm. [7] Cover plate arrangement according to one of the preceding claims, characterized by that it further comprises an insulating element, wherein the insulating element is slid onto the terminal post and arranged between the pressure plate and the cover plate to separate the pressure plate from the cover plate; and the Rockwell hardness of the insulating element is “K” and the Rockwell hardness “K” of the insulating element meets: 40≤K≤120. [8] Cover plate arrangement according to claim 7, characterized by , that it continues to have a sealing element, wherein the sealing element is pushed onto the terminal post, and the sealing element is located on the inside of the cover plate and between the cover plate and the flange edge section, and the projection of the sealing element on the plane in which the cover plate is located, corresponds to the projection the insulating element overlaps the plane where the cover plate is located. [9] Cover plate arrangement according to claim 8, characterized by that the cover plate has a groove arranged around the mounting hole, and the insulating element is at least partially arranged in the groove; and the thickness of the insulating element “t3” is, the thickness of the sealing element “t4” is, and the above parameters are met: 0.8≤t1+t3t2+t4≤4. [10] Cover plate arrangement according to claim 8, characterized by , that the pressure plate is welded to and fixed against the outer peripheral side of the terminal post, so that a weld mark is formed between the pressure plate and the terminal post; and the width of the weld mark “W3” is, the height of the weld mark “h” is, and the The compression rate of the sealing element “W” is, and the above parameters are met: 0.6≤W3×hW≤20. [11] Cover plate arrangement according to claim 8, characterized by , that the width of the sealing element is “W4” and that the above parameters meet the following: 0.4≤W4W2≤2.

5. [12] Cover plate arrangement according to one of the preceding claims, characterized by, that the thickness of the cover plate is “t5” and that the above parameters are met: 0.5≤t1t5≤3. [13] Battery, characterized by , that it comprises a cell and a cover plate arrangement according to one of claims 1-9 and that the output end of the cell is electrically connected to the terminal post. [14] Battery according to claim 13, characterized by , that the end face of the terminal post, which faces the outside of the cover plate, is connected to a conductive busbar. [15] Battery according to claim 14, characterized by , that the flange edge section is welded and fixed to the outlet end of the cell, and the weld area between the flange edge section and the outlet end of the cell “S I “ is, and the welding area between the terminal post and the conductive busbar “S2” is, where the above parameters then meet: 0,1≤S1S5≤7. [16] Battery according to claim 15, characterized bythat the welding area “S I “ between the flange edge section and the exit end of the cell: 78≤S1≤706mm 2 .

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