End cover assembly, battery, battery pack, and electrical system

Abstract

An end cover assembly (10), a battery (100), a battery pack (200), and an electrical system (1000). The end cover assembly (10) comprises a cover plate (11), an explosion-proof valve (12), an insulating plate assembly (13), and an adhesive member (17). The cover plate (11) comprises a first surface (111) and a second surface (112) facing away from each other in a thickness direction (Z), and the cover plate (11) is provided with an explosion-proof hole (113) penetrating through the first surface (111) and the second surface (112). The explosion-proof valve (12) is connected to the cover plate (11), and blocks the explosion-proof hole (113). The insulating plate assembly (13) comprises a third surface (131) and a fourth surface (132) facing away from each other in the thickness direction (Z), the third surface (131) facing the second surface (112). Two opposite surfaces of the adhesive member (17) are connected to the second surface (112) and the third surface (113), respectively. An orthographic projection of the adhesive member (17) onto the cover plate (11) is located in an adhesive region (116) of the second surface (112), and the adhesive member (17) and the adhesive region (116) satisfy the relational expression: 30%≤SJ1 / SJ2≤45%, SJ1 being the area of the the orthographic projection area of the adhesive member (17) onto the cover plate (11), and SJ2 being the area of the adhesive region (116).

Description

End cap assembly, battery, battery pack and power system

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 25, 2023, with application number 202322618354.X and application name “End cover assembly, battery, battery pack and power system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of energy storage equipment, and in particular to an end cover assembly, a battery, a battery pack, and an electricity system. Background Art

[0003] With the advancement of technology, batteries are increasingly used in modern society. Currently, a common battery consists of a casing, a cell assembly, and an end cap assembly. The cell assembly is housed within the casing, which is sealed by the end cap assembly. The cell tabs connect to the terminals on the end cap assembly. Furthermore, to ensure battery safety, explosion-proof valves are installed on the end cap assembly to release gas in the event of internal battery expansion.

[0004] However, the connection reliability between the various components inside the existing end cover assembly is poor, especially the cover plate and the insulating plate that are fixed only by the poles, so how to improve the reliability between the cover plate and the insulating plate becomes the key.

[0005] Summary of the Invention

[0006] The purpose of this application is to provide an end cover assembly, a battery, a battery pack and an electrical system to solve the problem of the reliability of the connection between the cover plate and the insulating plate.

[0007] To achieve the purpose of this application, this application provides the following technical solutions:

[0008] In a first aspect, the present application provides an end cover assembly, comprising a cover plate, an explosion-proof valve, an insulating plate group, and an adhesive; the cover plate comprises a first surface and a second surface opposite to each other in the thickness direction, the cover plate being provided with an explosion-proof hole penetrating the first surface and the second surface; the explosion-proof valve is connected to the cover plate and blocks the explosion-proof hole; the insulating plate group comprises a third surface and a fourth surface opposite to each other in the thickness direction, the third surface being closer to the second surface than the fourth surface; an adhesive is arranged between the cover plate and the insulating plate group, and the two opposite sides of the adhesive are respectively connected to the second surface and the third surface; the second surface has a bonding area, the orthographic projection of the adhesive on the cover plate is located within the bonding area, and the adhesive and the bonding area satisfy the relationship: 30%≤S J1 / S J2 ≤45%, where S J1 is the orthographic projection area of ​​the adhesive on the cover plate, SJ2 is the area of ​​the bonding region.

[0009] In one embodiment, the shortest distance between the edge of the adhesive and the edge of the explosion-proof valve is 2.5 mm to 12.5 mm.

[0010] In one embodiment, the insulating plate group includes a first insulating plate and a second insulating plate arranged opposite to each other along the length direction of the cover plate, the adhesive includes a first adhesive and a second adhesive, the second surface has a first adhesive area and a second adhesive area, the first adhesive is located in the first adhesive area, the second adhesive is located in the second adhesive area, the first adhesive is located between the first insulating plate and the cover plate, the second adhesive is located between the second insulating plate and the cover plate, and the explosion-proof valve is located between the first adhesive and the second adhesive.

[0011] In one embodiment, S J1 is the sum of the orthographic projection areas of the first adhesive member and the second adhesive member on the cover plate, S J2 is the sum of the areas of the first bonding area and the second bonding area; and / or, S J1 is the orthographic projection area of ​​the first adhesive member on the cover plate, S J2 is the area of ​​the first bonding area; and / or, S J1 is the orthographic projection area of ​​the second adhesive member on the cover plate, S J2 is the area of ​​the second bonding region.

[0012] In one embodiment, in the length direction of the cover plate, the shortest distances from two opposite ends of the cover plate to the explosion-proof hole are the same, and the length of the first insulating plate is greater than the length of the second insulating plate.

[0013] In one embodiment, the length of the first insulating plate is greater than the length of the second insulating plate, and the first adhesive member and the second adhesive member satisfy the relationship: k>l, where k is the shortest distance between the edge of the first adhesive member and the edge of the explosion-proof valve, and l is the shortest distance between the edge of the second adhesive member and the edge of the explosion-proof valve.

[0014] In one embodiment, 9mm≤k≤12.5mm, 2mm≤l≤3.5mm.

[0015] In one embodiment, in the thickness direction of the cover plate, the thickness of the adhesive is 0.01 mm to 0.1 mm.

[0016] In one embodiment, a first receiving groove is formed on a side of the first insulating plate facing the cover plate; a second receiving groove is formed on a side of the second insulating plate facing the cover plate, and the first receiving groove and the second receiving groove constitute a receiving groove.

[0017] In one embodiment, the first accommodating groove extends along the length direction of the cover plate to the side of the first insulating plate facing the second insulating plate to form a first notch; the second accommodating groove extends along the length direction of the cover plate to the side of the second insulating plate facing the first insulating plate to form a second notch.

[0018] In one embodiment, the insulating plate group is provided with air holes, and the air holes are arranged corresponding to the explosion-proof valve. There are multiple air holes, and the air holes include a first air hole and a second air hole. The first air hole is opened in the first insulating plate, and the second air hole is opened in the second insulating plate.

[0019] In one embodiment, the end cover assembly further includes a pole, and the pole includes a first pole and a second pole, the first pole is provided through the cover plate and the first insulating plate, and the second pole is provided through the cover plate and the second insulating plate.

[0020] In one embodiment, the cover plate is further provided with a pole hole and a first liquid injection hole passing through the first surface and the second surface; the pole hole includes a first pole hole and a second pole hole, and the first pole hole and the second pole hole are respectively located at opposite ends of the cover plate along the length direction of the cover plate.

[0021] In one embodiment, when the first electrode hole is a positive electrode hole, the first liquid injection hole is located between the first electrode hole and the explosion-proof hole; or when the second electrode hole is a positive electrode hole, the first liquid injection hole is located between the second electrode hole and the explosion-proof hole.

[0022] In one embodiment, the first adhesive member is located between the explosion-proof hole and the first pole hole, and the second adhesive member is located between the explosion-proof hole and the second pole hole.

[0023] In one embodiment, a third pole hole is formed at one end of the first insulating plate away from the second insulating plate, and a fourth pole hole is formed at one end of the second insulating plate away from the first insulating plate; the first insulating plate or the second insulating plate further comprises a second liquid injection hole; the third pole hole is directly opposite to the first pole hole, the fourth pole hole is directly opposite to the second pole hole, and the second liquid injection hole is directly opposite to the first liquid injection hole.

[0024] In a second aspect, the present application further provides a battery, comprising a cell assembly, a shell, and an end cap assembly according to any one of the embodiments of the first aspect, wherein the cell assembly is accommodated in the shell, and the end cap assembly is connected to the shell.

[0025] In one embodiment, the end cap assembly closes the opening of the shell, and the end cap assembly is electrically connected to the battery core assembly.

[0026] In a third aspect, the present application also provides a battery pack comprising the battery described in the second aspect.

[0027] In a fourth aspect, the present application further provides a power system comprising the battery pack described in the third aspect or the battery described in the second aspect.

[0028] The present application provides an insulating plate group to ensure the insulation effect between the cover plate and the battery cell assembly, and provides an adhesive between the cover plate and the insulating plate group to achieve the connection and fixation of the insulating plate group and the cover plate. In addition, by ensuring that the relationship between the orthographic projection area of ​​the adhesive on the cover plate and the area of ​​the adhesive area satisfies 30%≤S J1 / S J2 ≤45%, on the one hand, it ensures the bonding effect between the insulation plate group and the cover plate, and improves the firmness of the connection between the cover plate and the insulation plate group; on the other hand, it also reduces the bonding cost and reduces excessive waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the implementation methods or the description of the prior art. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] FIG1 is a schematic exploded view of a battery structure according to an embodiment;

[0031] FIG2 is a schematic exploded view of the structure of an end cap assembly according to an embodiment;

[0032] FIG3 is a top view of an insulating plate assembly according to an embodiment;

[0033] FIG4 is a schematic diagram of the appearance structure of an adhesive member connected to the back of a cover plate in one embodiment;

[0034] FIG5 is a schematic diagram of a battery pack according to an embodiment;

[0035] FIG6 is a schematic diagram of an electric power system according to an embodiment.

[0036] Explanation of Reference Numerals: 100 - battery, 10 - end cap assembly, 20 - cell assembly, 30 - housing; 200 - battery pack; 1000 - power system; 21 - cell, 22 - tab, 22A - positive tab, 22B - negative tab; 11 - cover plate, 111 - first surface, 112 - second surface, 113 - explosion-proof hole, 114A - first pole hole, 114B - second pole hole, 115 - first liquid injection hole, 116 - bonding area, 116A - first bonding area, 116B - second bonding area; 12 - explosion-proof valve; 13 - insulating plate assembly, 131 - third surface, 132 - fourth surface, 133 - receiving groove, 134 - vent hole, 134A - first vent hole, 134B - second vent hole, 135 - gap, 136 - second liquid injection hole; 13A-first insulating plate, 131A-third left surface, 132A-fourth left surface, 13A1-first opposite end, 13A2-first connecting end, 13A3-third pole hole, 13A4-first accommodating groove, 13A5-first notch, 13B5-second notch; 13B-second insulating plate, 131B-third right surface, 132B-fourth right surface, 13B1-second opposite end, 13B2-second connecting end, 13B3-fourth pole hole, 13B4-second accommodating groove; 14-pole, 14A-first pole, 14B-second pole; 17-adhesive, 17A-first adhesive, 17B-second adhesive; X-length direction, Y-width direction, Z-thickness direction. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0038] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may be an intermediate component. When a component is referred to as being "connected to" another component, it may be directly connected to the other component or there may be an intermediate component.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the relevant listed items.

[0040] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0041] The present application provides a battery 100. Referring to FIG1 , the battery 100 includes a housing 30, a cell assembly 20, and an end cap assembly 10. The cell assembly 20 is disposed within the housing 30. The end cap assembly 10 is connected to the housing 30 and seals an opening of the housing 30. The end cap assembly 10 is also electrically connected to the cell assembly 20.

[0042] Optionally, the battery 100 may be in the shape of a rectangular parallelepiped. The battery 100 includes a length direction, a width direction, and a height direction (thickness direction). The direction in which the cell assembly 20 is placed into the housing 30 through the opening of the housing 30 is the height direction of the battery 100. The long side of the opening of the housing 30 is the length direction, and the short side is the width direction.

[0043] Referring to Figure 1 , the battery cell assembly 20 includes a battery cell 21 and tabs 22 . The battery cell 21 can be rectangular, and there can be two battery cells 21 . The two battery cells 21 are stacked along the width direction Y and housed in the housing 30 . The tabs 22 include a positive tab 22A and a negative tab 22B. Each battery cell 21 is provided with a positive tab 22A and a negative tab 22B at opposite ends in the length direction X. The battery cell 21 is formed by stacking a positive electrode sheet, a separator, and a negative electrode sheet in this order.

[0044] In one embodiment, referring to FIG. 1 and FIG. 2 , the end cover assembly 10 includes a cover plate 11 , an explosion-proof valve 12 , an insulating plate group 13 , a pole 14 , and an adhesive 17 .

[0045] The cover plate 11 may be a flat plate structure. The length direction X of the cover plate 11 may be the length direction X of the battery 100, the width direction Y of the cover plate 11 may be the width direction Y of the battery 100, and the thickness direction Z of the cover plate 11 may be the height direction of the battery 100. It should be noted that the length direction X, width direction Y, and thickness direction Z mentioned below are all referenced to the cover plate 11.

[0046] 1 and 2 , the cover plate 11 includes a first surface 111 and a second surface 112 facing each other in the thickness direction Z. The first surface 111 faces outward, and the second surface 112 faces the battery cell assembly 20. The cover plate 11 is provided with an explosion-proof hole 113, a terminal hole, and a first liquid injection hole 115 that pass through the first and second surfaces 111 and 112.

[0047] Preferably, the explosion-proof hole 113 is located in the middle of the cover plate 11 and can be elliptical in shape. In the length direction X of the cover plate 11, the shortest distances from the two opposite ends of the cover plate 11 to the explosion-proof hole are the same.

[0048] There are two pole holes, as shown in Figure 2 : a first pole hole 114A and a second pole hole 114B. The first pole hole 114A and the second pole hole 114B are located at opposite ends of the cover plate 11 along the length direction X. Both pole holes are circular. Optionally, the first pole hole 114A can be a positive pole hole, and the second pole hole 114B can be a negative pole hole; alternatively, the first pole hole 114A can be a negative pole hole, and the second pole hole 114B can be a positive pole hole.

[0049] Referring to Figure 2 , first injection hole 115 can be circular in shape. Alternatively, first injection hole 115 can be located between first electrode hole 114A and explosion-proof hole 113 ; or, first injection hole 115 can be located between second electrode hole 114B and explosion-proof hole 113 . It is understood that first injection hole 115 needs to be located between the positive electrode hole and explosion-proof hole 113 .

[0050] The explosion-proof valve 12 is connected to the cover plate 11 and blocks the explosion-proof hole 113. Optionally, the explosion-proof valve 12 is connected to the second surface 112 by methods including, but not limited to, gluing, welding, or clamping. The explosion-proof valve 12 can also be disposed within the explosion-proof hole 113, so that the outer periphery of the explosion-proof valve 12 is connected to the inner wall of the explosion-proof hole 113.

[0051] Optionally, an indentation may be formed on the explosion-proof valve 12. The thickness of the explosion-proof valve 12 at the indentation may be smaller than the thickness at the non-indentation location. The purpose of providing the indentation is to facilitate the explosion-proof valve 12 to burst open when the internal pressure of the battery 100 increases. Therefore, the shape and size of the indentation are not specifically limited.

[0052] Referring to FIG. 2 , the insulating plate assembly 13 includes a third surface 131 and a fourth surface 132 facing each other in the thickness direction Z. The third surface 131 faces and connects to the second surface 112 . The third surface 131 defines a receiving groove 133 . The orthographic projection of the explosion-proof valve 12 on the insulating plate assembly 13 is located within the receiving groove 133 . The bottom wall of the receiving groove 133 defines a vent hole 134 extending through the fourth surface 132 .

[0053] Optionally, the insulating plate assembly 13 may be a flat plate structure, and the length and width of the insulating plate assembly 13 may be the same as or slightly smaller than the cover plate 11. The insulating plate assembly 13 is located between the battery cell assembly 20 and the cover plate 11 to isolate the cover plate 11 from the battery cell assembly 20. The insulating plate assembly 13 may be made of an insulating material, such as plastic.

[0054] 1 to 4 , the adhesive member 17 is disposed between the cover plate 11 and the insulating plate assembly 13 , and two opposite surfaces of the adhesive member 17 are respectively connected to the cover plate 11 and the insulating plate assembly 13 .

[0055] In one embodiment, referring to FIG. 3 and FIG. 4 , the second surface 112 has a bonding area 116 (in the dotted box of FIG. 4 ), and the adhesive 17 and the bonding area 116 satisfy the relationship: 30% ≤ S J1 / S J2 ≤45%, where S J1 is the orthographic projection area of ​​the adhesive 17 on the insulating plate group 13, S J2 is the area of ​​the bonding region 116 .

[0056] Specifically, as shown in FIG4 , the bonding area 116 has two endpoints for the maximum dimension of the adhesive 17 along the length direction of the cover plate (i.e., the maximum dimension of the outer periphery of the adhesive 17 parallel to the length direction of the cover plate). A horizontal line is drawn through the two endpoints along the width direction of the cover plate, and the horizontal line intersects with the two edges of the cover plate along its length direction. The bonding area is the area enclosed by the horizontal line passing through the endpoints and the two edges of the cover plate along the length direction. The width of the bonding area 116 is the width of the cover plate 11, and the length of the bonding area 116 is the length of the adhesive 17 in the length direction X of the cover plate 11. The adhesive 17 is entirely located within the bonding area 116. Therefore, when the length of the bonding area 116 is the same as the length of the adhesive 17, the above relationship actually represents the ratio of the width of the adhesive 17 to the width of the cover plate 11 in the width direction.

[0057] Optional, S J1 / S J2 It can be, but is not limited to, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, and 45%. J1 / S J2 If it is smaller than the above range, it means that the size of the adhesive 17 is too small, and its bonding effect on the cover plate 11 and the insulating plate group 13 is poor. When the bonding is not firm, the insulating plate group 13 will move relative to the cover plate 11. J1 / S J2 When the size is larger than the above range, it indicates that the adhesive member 17 is too large, which not only wastes materials but also blocks the transverse airflow between the cover plate 11 and the insulating plate group 13, which is not conducive to gas flow.

[0058] On the basis of satisfying the above advantages, the firmness of the insulating plate group 13 being bonded to the cover plate 11 by the adhesive 17 is improved; when the adhesive is not provided, the insulating plate group 13 is only sleeved on the pole 14 by the connecting end and fixed by the connection between the lead-out piece and the pole 14, which may easily cause the opposite end of the insulating plate group 13 to move in the vertical or horizontal direction and expose the welding area of ​​the explosion-proof valve 12, so it is necessary to fix the opposite end by providing an adhesive.

[0059] The adhesive 17 can be provided to enhance the connection strength between the cover plate 11 and the insulating plate group 13. When the adhesive is not provided, the insulating plate group 13 is only connected and fixed to the cover plate 11 through the pole 14, so that the first insulating plate 13A and the second insulating plate 13B rotate relative to each other around the pole 14, which not only exposes the welding area of ​​the explosion-proof valve 12, but also makes the accommodating groove 133 unable to face the explosion-proof valve 12, and the explosion-proof valve 12 cannot be effectively opened after the internal air pressure of the battery 100 increases.

[0060] In one embodiment, the shortest distance between the edge of the adhesive 17 and the edge of the explosion-proof valve 12 is 2.5 mm to 12.5 mm.

[0061] Specifically, based on the above embodiment, the shortest distance between the edge of the adhesive 17 and the edge of the explosion-proof valve 12 should be the shortest distance from the edge of the adhesive 17 to the arc edge of the explosion-proof valve 12 .

[0062] Optionally, the shortest distance between the edge of adhesive 17 and the edge of explosion-proof valve 12 is 2.5mm, 3.5mm, 4.5mm, 5.5mm, 6.5mm, 7.5mm, 8.5mm, 9.5mm, 10.5mm, 11.5mm, or 12.5mm. If the distance is less than the above range, the adhesive 17 is too close to the explosion-proof valve 12, increasing the process precision. Furthermore, if the adhesive 17 deviates, it is likely to connect to the explosion-proof valve 12, thereby preventing the explosion of the explosion-proof valve 12. If the distance is greater than the above range, the adhesive 17 is too far from the explosion-proof valve 12, resulting in excessive unfixed portions of the opposite ends of the insulating plate assembly 13, making it prone to deviation.

[0063] In one embodiment, referring to FIG2 , the insulating plate assembly 13 includes a first insulating plate 13A and a second insulating plate 13B disposed opposite each other along the length direction X of the cover plate 11 . The first insulating plate 13A and the second insulating plate 13B collectively enclose a receiving groove 133 , with a gap 135 defined between the first insulating plate 13A and the second insulating plate 13B. It will be appreciated that the first insulating plate 13A and the second insulating plate 13B may be separate insulating plates, so the gap 135 between the first insulating plate 13A and the second insulating plate 13B represents the distance between them. The first insulating plate 13A and the second insulating plate 13B may be the same length or different lengths.

[0064] Alternatively, the first insulating plate 13A may be a positive insulating plate, and the second insulating plate 13B may be a negative insulating plate. Of course, in this embodiment, the first insulating plate 13A may be a negative insulating plate, and the second insulating plate 13B may be a positive insulating plate. It is understood that the positive insulating plate may be used to connect to the positive electrode of the battery cell assembly 20, and the negative insulating plate may be used to connect to the negative electrode of the battery cell assembly 20. Therefore, there is no specific limitation on the first insulating plate 13A and the second insulating plate 13B.

[0065] In one embodiment, the adhesive member 17 includes a first adhesive member 17A and a second adhesive member 17B. The first adhesive member 17A connects the cover plate 11 and the first insulating plate 13A, and the second adhesive member 17B connects the cover plate 11 and the second insulating plate 13B.

[0066] Optionally, the first adhesive member 17A is located between the explosion-proof hole 113 and the first pole hole 114A, and the second adhesive member 17B is located between the explosion-proof hole 113 and the second pole hole 114B.

[0067] Optionally, the projection of the adhesive member 17 on the insulating plate group 13 is a quadrilateral. Preferably, the projection of the adhesive member 17 on the insulating plate group 13 is a square.

[0068] In one embodiment, the second surface 112 has a first adhesive region 116A and a second adhesive region 116B. The first adhesive member 17A is located in the first adhesive region 116A, and the second adhesive member 17B is located in the second adhesive region 116B.

[0069] In one embodiment, S J1 is the sum of the orthographic projection areas of the first adhesive member 17A and the second adhesive member 17B on the cover plate 11, S J2 It is the sum of the areas of the first adhesive region 116A and the second adhesive region 116B.

[0070] In one embodiment, S J1 is the orthographic projection area of ​​the first adhesive member 17A on the cover plate 11, S J2 is the area of ​​the first bonding region 116A.

[0071] In one embodiment, S J1 is the orthographic projection area of ​​the second adhesive member 17B on the cover plate 11, S J2 is the area of ​​the second bonding region 116B.

[0072] In one embodiment, S J1 is the orthographic projection area of ​​the first adhesive member 17A on the cover plate 11, S J2 is the area of ​​the first bonding region 116A. And S J1 S is also the orthographic projection area of ​​the second adhesive member 17B on the cover plate 11, J2 That is, the area ratio between the first adhesive and the first adhesive region 116A and the area ratio between the second adhesive and the second adhesive region 116B both meet the above ranges, thereby improving the bonding reliability between the first and second insulating plates.

[0073] In one embodiment, referring to FIG4 , the length of first insulating plate 13A is greater than the length of second insulating plate 13B, and first adhesive member 17A and second adhesive member 17B satisfy the relationship: k>l. Here, k is the shortest distance between the edge of first adhesive member 17A and the edge of explosion-proof valve 12, i.e., E1, and l is the shortest distance between the edge of second adhesive member 17B and the edge of explosion-proof valve 12, i.e., E2.

[0074] Furthermore, k and l satisfy the following relationship: 9mm≤k≤12.5mm, 2mm≤l≤3.5mm.

[0075] Specifically, as shown in Figures 3 and 4 , when the lengths of the first insulating plate 13A and the second insulating plate 13B are different, and the length of the first insulating plate 13A is greater than the length of the second insulating plate 13B, it is easy to understand that the length of the first accommodating groove 13A4 is greater than the length of the second accommodating groove 13B4. Therefore, when the shortest distance between the edges of the first and second adhesive members 17A, 17B, and the edge of the explosion-proof valve 12 is the same, the further the first adhesive member 17A is from the edge of the first insulating plate 13A closest to the second insulating plate 13B in the longitudinal direction X, the closer the second adhesive member 17B is to the edge of the second insulating plate 13B closest to the first insulating plate 13A. This phenomenon results in an excessive amount of unfixed portion of the first opposing end 13A1, making it prone to misalignment.

[0076] Therefore, when the lengths of the first insulating plate 13A and the second insulating plate 13B are different, in order to reduce the number of unfixed portions at the opposite ends, the shortest distance between the edges of the first and second adhesive members 17A, 17B and the edge of the explosion-proof valve 12 can be appropriately adjusted. In other words, the first adhesive member 17A is adjusted to be closer to the edge of the first insulating plate 13A near the second insulating plate 13B.

[0077] When the above relationship is not satisfied, the first adhesive member 17A is far from the edge of the first insulating plate 13A close to the second insulating plate 13B, and the first opposite end 13A1 is excessively unfixed, which can easily cause displacement.

[0078] It can be understood that when the length of the first insulating plate 13A is less than the length of the second insulating plate 13B, the lengths can be 9 mm ≤ l ≤ 12.5 mm, and 2 mm ≤ k ≤ 3.5 mm.

[0079] In one embodiment, in the thickness direction Z of the cover plate 11 , the thickness of the adhesive 17 is 0.01 mm to 0.1 mm.

[0080] Specifically, because the adhesive 17 is located between the cover plate 11 and the insulating plate assembly 13, the thickness of the end cap assembly 10 depends on the sum of the thicknesses of the cover plate 11, the adhesive 17, and the insulating plate assembly 13. When the thicknesses of the cover plate 11 and the insulating plate assembly 13 are fixed, the thickness of the end cap assembly 10 can be adjusted (e.g., reduced) by controlling the thickness of the adhesive 17.

[0081] Optionally, the thickness of adhesive 17 is 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, or 0.1 mm. If the thickness is less than the above range, adhesive 17 is too thin, requiring a higher level of manufacturing difficulty. Furthermore, since adhesive 17 is double-sided, an excessively thin adhesive 17 can also affect its bonding performance. If the thickness is greater than the above range, adhesive 17 is too thick, hindering the reduction of the thickness of end cap assembly 10.

[0082] In one embodiment, the first insulating plate 13A and the second insulating plate 13B have the same thickness. Referring to Figures 2 and 3 , it can be understood that the first insulating plate 13A has a third left surface 131A and a fourth left surface 132A facing each other, and the second insulating plate 13B has a third right surface 131B and a fourth right surface 132B facing each other. The third left surface 131A and the third right surface 131B constitute the third surface 131, and the fourth left surface 132A and the fourth right surface 132B constitute the fourth surface 132. Both the first insulating plate 13A and the second insulating plate 13B are provided with ventilation holes 134. There are multiple ventilation holes 134, including a first ventilation hole 134A and a second ventilation hole 134B. The first ventilation hole 134A is provided in the first insulating plate 13A, and the second ventilation hole 134B is provided in the second insulating plate 13B.

[0083] Optionally, referring to Figure 3 , the first insulating plate 13A further includes a first opposing end 13A1 and a first connecting end 13A2, and the second insulating plate 13B further includes a second opposing end 13B1 and a second connecting end 13B2. The first opposing end 13A1 and the first connecting end 13A2 are located at opposite ends of the first insulating plate 13A along the length direction X, while the second opposing end 13B1 and the second connecting end 13B2 are located at opposite ends of the second insulating plate 13B along the length direction X. The first opposing end 13A1 and the second opposing end 13B1 are adjacent to each other. Together, the first opposing end 13A1 and the second opposing end 13B1 enclose the accommodating groove 133.

[0084] Furthermore, referring to Figure 3 , a third terminal hole 13A3 is defined at one end of the first insulating plate 13A remote from the second insulating plate 13B (first connection end 13A2). A fourth terminal hole 13B3 is defined at one end of the second insulating plate 13B remote from the first insulating plate 13A (second connection end 13B2). A second liquid injection hole 136 is also defined on either the first insulating plate 13A or the second insulating plate 13B. Third terminal hole 13A3 directly faces first terminal hole 114A, fourth terminal hole 13B3 directly faces second terminal hole 114B, and second liquid injection hole 136 directly faces first liquid injection hole 115.

[0085] Referring to Figure 2 , the poles 14 include a first pole 14A and a second pole 14B. The structures of the first and second poles 14A and 14B are substantially identical. The poles 14 extend through the cover plate 11 and the insulating plate assembly 13. Specifically, the first pole 14A extends through the cover plate 11 and the first insulating plate 13A, while the second pole 14B extends through the cover plate 11 and the second insulating plate 13B.

[0086] Optionally, the first pole 14A may be a positive pole 14, and the second pole 14B may be a negative pole 14. Of course, in the embodiment, the first pole 14A may be a negative pole 14, and the second pole 14B may be a positive pole 14.

[0087] It can be understood that the first pole 14A should pass through the first pole hole 114A and the third pole hole 13A3, and the second pole 14B should pass through the second pole hole 114B and the fourth pole hole 13B3.

[0088] In one embodiment, please refer to Figures 3 and 4. A first accommodating groove 13A4 is formed on a side of the first insulating plate 13A facing the cover plate 11, and the first accommodating groove 13A4 extends along the length direction X of the cover plate 11 to the side of the first insulating plate 13A facing the second insulating plate 13B to form a first notch 13A5; a second accommodating groove 13B4 is formed on a side of the second insulating plate 13B facing the cover plate 11, and the second accommodating groove 13B4 extends along the length direction X of the cover plate 11 to the side of the second insulating plate 13B facing the first insulating plate 13A to form a second notch 13B5. The first accommodating groove 13A4 and the second accommodating groove 13B4 constitute a accommodating groove 133.

[0089] Specifically, based on the above embodiment, the accommodating groove 133 may include a first accommodating groove 13A4 and a second accommodating groove 13B4, the first accommodating groove 13A4 is located on the first opposite end 13A1, the second accommodating groove 13B4 is located on the second opposite end 13B1, and the gap 135 is located between the first accommodating groove 13A4 and the second accommodating groove 13B4.

[0090] A first receiving groove 13A4 is defined on the third left surface 131A. This groove 13A4 extends along the length direction X to the side of the first insulating plate 13A facing the second insulating plate 13B, forming a first notch 13A5. A second receiving groove 13B4 is defined on the third right surface 131B. This groove 13B4 extends along the length direction X to the side of the second insulating plate 13B facing the first insulating plate 13A, forming a second notch 13B5. Therefore, there is no obstruction between the bottom wall of the first receiving groove 13A4 and the bottom wall of the second receiving groove 13B4.

[0091] By setting the first accommodating groove 13A4 to extend to one side of the first insulating plate 13A to form the first notch 13A5, and setting the second accommodating groove 13B4 to extend to one side of the second insulating plate 13B to form the second notch 13B5, there is no obstruction between the bottom wall of the first accommodating groove 13A4 and the bottom wall of the second accommodating groove 13B4. When the explosion-proof valve 12 is accommodated in the accommodating groove 133, a gap can be retained between the explosion-proof valve 12 and the bottom wall of the accommodating groove 133, thereby forming a certain pressure relief space. When the gas inside the battery 100 is pressurized, the pressure relief space can provide greater gas pressure and then cause the explosion-proof valve 12 to explode.

[0092] In one embodiment, please refer to FIG5 , the present application further provides a battery pack 200 , and the battery pack 200 includes the battery 100 in the above embodiment.

[0093] In one embodiment, referring to Figure 6 , the present application further provides an electric power system 1000, which includes the battery pack 200 in the above embodiment. Optionally, the electric power system 1000 can be a vehicle or an energy storage power station.

[0094] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship of terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", and "outside" are based on the orientation or positional relationship of the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0095] The above disclosure is only a preferred embodiment of the present application, and certainly cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present application are still within the scope covered by the present application.

Claims

1. An end cap assembly (10), characterized in that: include: A cover plate (11), comprising a first surface (111) and a second surface (112) opposite to each other in a thickness direction (Z), wherein the cover plate (11) is provided with an explosion-proof hole (113) penetrating the first surface (111) and the second surface (112); An explosion-proof valve (12) connected to the cover plate (11) and sealing the explosion-proof hole (113); An insulating plate group (13), comprising a third surface (131) and a fourth surface (132) facing each other in the thickness direction (Z), wherein the third surface (131) is closer to the second surface (112) than the fourth surface (132); and An adhesive member (17) is arranged between the cover plate (11) and the insulating plate group (13), and two opposite sides of the adhesive member (17) are respectively connected to the second surface (112) and the third surface (131); the second surface (112) has an adhesive area (116), the orthographic projection of the adhesive member (17) on the cover plate (11) is located in the adhesive area (116), and the adhesive member (17) and the adhesive area (116) satisfy the relationship: 30% ≤ S J1 / S J2 ≤45%, where S J1 is the orthographic projection area of ​​the adhesive member (17) on the cover plate (11), S J2 is the area of ​​the bonding region (116).

2. The end cap assembly (10) according to claim 1, characterized in that: The shortest distance between the edge of the adhesive member (17) and the edge of the explosion-proof valve (12) is 2.5 mm to 12.5 mm.

3. The end cap assembly (10) according to claim 1 or 2, characterized in that: The insulating plate group (13) comprises a first insulating plate (13A) and a second insulating plate (13B) which are arranged opposite to each other along the length direction of the cover plate (11); the adhesive member (17) comprises a first adhesive member (17A) and a second adhesive member (17B); the second surface (112) has a first adhesive region (116A) and a second adhesive region (116B); the first adhesive member (17A) is located in the first adhesive region (116A); the second adhesive member (17B) is located in the second adhesive region (116B); the first adhesive member (17A) is located between the first insulating plate (13A) and the cover plate (11); the second adhesive member (17B) is located between the second insulating plate (13B) and the cover plate (11); and the explosion-proof valve (12) is located between the first adhesive member (17A) and the second adhesive member (17B).

4. The end cap assembly (10) according to claim 3, characterized in that: S J1 is the sum of the orthographic projection areas of the first adhesive member (17A) and the second adhesive member (17B) on the cover plate (11), S J2 is the sum of the areas of the first bonding area (116A) and the second bonding area (116B); and / or S J1 is the orthographic projection area of ​​the first adhesive member (17A) on the cover plate (11), S J2 is the area of ​​the first bonding region (116A); and / or S J1 is the orthographic projection area of ​​the second adhesive member (17B) on the cover plate (11), S J2 is the area of ​​the second bonding region (116B).

5. The end cap assembly (10) according to claim 3 or 4, characterized in that: In the length direction of the cover plate (11), the shortest distances from the two opposite ends of the cover plate (11) to the explosion-proof hole (113) are the same, and the length of the first insulating plate (13A) is greater than the length of the second insulating plate (13B).

6. The end cap assembly (10) according to any one of claims 3 to 5, characterized in that: The first adhesive member (17A) and the second adhesive member (17B) satisfy the relationship: k>l, wherein, k is the shortest distance between the edge of the first adhesive member (17A) and the edge of the explosion-proof valve (12), and l is the shortest distance between the edge of the second adhesive member (17B) and the edge of the explosion-proof valve (12).

7. The end cap assembly (10) according to claim 6, characterized in that: 9mm≤k≤12.5mm, 2mm≤l≤3.5mm.

8. The end cap assembly (10) according to any one of claims 1 to 7, characterized in that: In the thickness direction (Z) of the cover plate (11), the thickness of the adhesive (17) is 0.01 mm to 0.1 mm.

9. The end cap assembly (10) according to any one of claims 3 to 6, characterized in that: A first receiving groove (13A4) is formed on one side of the first insulating plate (13A) facing the cover plate (11); a second receiving groove (13B4) is formed on one side of the second insulating plate (13B) facing the cover plate (11); the first receiving groove (13A4) and the second receiving groove (13B4) constitute a receiving groove (133).

10. The end cap assembly (10) according to claim 9, characterized in that: The first accommodating groove (13A4) extends along the length direction (X) of the cover plate (11) to a side of the first insulating plate (13A) facing the second insulating plate (13B) to form a first notch (13A5); the second accommodating groove (13B4) extends along the length direction (X) of the cover plate (11) to a side of the second insulating plate (13B) facing the first insulating plate (13A) to form a second notch (13B5).

11. The end cap assembly (10) according to any one of claims 3 to 6, characterized in that: The insulating plate group (13) is provided with air holes (134), and the air holes (134) are arranged corresponding to the explosion-proof valve (12). The number of the air holes (134) is multiple, and the air holes (134) include a first air hole (134A) and a second air hole (134B). The first air hole (134A) is opened in the first insulating plate (13A), and the second air hole (134B) is opened in the second insulating plate (13B).

12. The end cap assembly (10) according to any one of claims 3 to 11, characterized in that: The end cover assembly (10) further comprises a pole (14), wherein the pole (14) comprises a first pole (14A) and a second pole (14B), wherein the first pole (14A) is disposed through the cover plate (11) and the first insulating plate (13A), and the second pole (14B) is disposed through the cover plate (11) and the second insulating plate (13B).

13. The end cap assembly (10) according to any one of claims 3 to 7 and 9 to 12, characterized in that: The cover plate (11) is further provided with a pole hole and a first liquid injection hole (115) penetrating the first surface (111) and the second surface (112); the pole hole comprises a first pole hole (114A) and a second pole hole (114B); the first pole hole (114A) and the second pole hole (114B) are respectively located at two opposite ends of the cover plate (11) along the length direction (X) of the cover plate (11).

14. The end cap assembly (10) according to claim 13, characterized in that: When the first pole hole (114A) is a positive pole hole, the first liquid injection hole (115) is located between the first pole hole (114A) and the explosion-proof hole (113); or When the second pole hole (114B) is a positive pole hole, the first liquid injection hole (115) is located between the second pole hole (114B) and the explosion-proof hole (113).

15. The end cap assembly (10) according to claim 13 or 14, characterized in that: The first adhesive member (17A) is located between the explosion-proof hole (113) and the first pole hole (114A), and the second adhesive member (17B) is located between the explosion-proof hole (113) and the second pole hole (114B).

16. The end cap assembly (10) according to any one of claims 13 to 15, characterized in that: A third pole hole (13A3) is provided at one end of the first insulating plate (13A) away from the second insulating plate (13B), and a fourth pole hole (13B3) is provided at one end of the second insulating plate (13B) away from the first insulating plate (13A); the first insulating plate (13A) or the second insulating plate (13B) is also provided with a second liquid injection hole (136); the third pole hole (13A3) and the first pole hole (114A) are opposite to each other, the fourth pole hole (13B3) and the second pole hole (114B) are opposite to each other, and the second liquid injection hole (136) and the first liquid injection hole (115) are opposite to each other.

17. A battery (100), characterized in that: It comprises an end cap assembly (10) as claimed in any one of claims 1 to 16, a battery cell assembly (20) and a shell (30), wherein the battery cell assembly (20) is accommodated in the shell (30), and the end cap assembly (10) and the shell (30) are connected.

18. The battery (100) according to claim 17, characterized in that: The end cover assembly (10) closes the opening of the housing (30), and the end cover assembly (10) is electrically connected to the battery cell assembly (20).

19. A battery pack (200), characterized in that: Comprising the battery (100) as claimed in claim 18.

20. An electricity system (1000), characterized in that: Comprising the battery pack (200) as claimed in claim 19 or the battery (100) as claimed in claim 17.

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