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

Abstract

An end cover assembly (10), a battery (100), a battery pack (200), and an electric system (300). The end cover assembly (10) comprises a cover plate (11), an explosion-proof valve (12), and an insulating plate group (13). The cover plate (11) comprises a first surface (111) and a second surface (112) facing away from each other in the thickness direction of the cover plate (11), and the cover plate (11) is provided with an explosion-proof hole (113) running 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), and the explosion-proof valve (12) is provided with an opening region (121); the insulating plate group (13) comprises a third surface (131) and a fourth surface (132) facing away from each other in the thickness direction of the insulating plate group (13), the third surface (131) is connected to the second surface (112), the insulating plate group (13) is provided with a gap (135), at least part of the orthographic projection of the explosion-proof valve (12) on the insulating plate group (13) overlaps the gap (135), and the area SG1 of the gap (135) and the area SF1 of the opening region (121) satisfy the relational expression: 0.03≤SG1 / SF1≤0.15.

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 202322628833.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, the use of batteries is becoming increasingly widespread. 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. To ensure battery safety, the end cap assembly is typically equipped with an explosion-proof valve that can explode and release air in the event of internal battery inflation.

[0004] However, the explosion-proof valves in existing end cap assemblies have a slow response speed. When gas is rapidly generated inside a battery, the valve's response speed determines the battery's safety. Furthermore, after the valves burst, combustion residue inside the battery is easily ejected, causing secondary hazards. Therefore, solving the problems of slow explosion-proof valve response and the ejection of combustion residue inside the battery has become a key issue.

[0005] Summary of the Invention

[0006] The present application provides an end cap assembly, a battery, a battery pack, and a power system, which aim to solve the problems of slow response of explosion-proof valves and ejection of combustion residues.

[0007] To solve the above technical problems, this application provides the following technical solutions.

[0008] In a first aspect, the present application provides an end cap assembly. The end cap assembly includes a cover plate, an explosion-proof valve, and an insulating plate group; the cover plate includes a first surface and a second surface opposite to each other in the thickness direction of the cover plate, and the cover plate is 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, and the explosion-proof valve has an opening area; the insulating plate group includes a third surface and a fourth surface opposite to each other in the thickness direction of the insulating plate group, the third surface is close to the second surface, the insulating plate group has a gap, at least part of the orthographic projection of the explosion-proof valve on the insulating plate group coincides with the gap, and the area S of the gap is 1 / 4. G1 and the area S of the opening area F1Satisfy the relationship: 0.03≤S G1 / S F1 ≤0.15.

[0009] In some embodiments, the insulating plate set includes a first insulating plate and a second insulating plate disposed opposite to each other along a length direction of the cover plate, and the gap is between the first insulating plate and the second insulating plate.

[0010] In some embodiments, the width of the gap is in the range of 0.5 mm to 3 mm.

[0011] In some embodiments, the insulating plate assembly is provided with a receiving groove, an opening of the receiving groove is away from the fourth surface of the insulating plate assembly, and an orthographic projection of the explosion-proof valve on the insulating plate assembly is located in the receiving groove.

[0012] In some embodiments, the accommodating tank and the explosion-proof valve satisfy the relationship: 0.3≤F1 / G1≤1, wherein F1 is the orthographic projection area of ​​the explosion-proof valve on the insulating plate group, and G1 is the orthographic projection area of ​​the accommodating tank on the cover plate.

[0013] In some embodiments, the explosion-proof valve has two opposite straight edges and two opposite arc edges, two ends of the straight edges are respectively connected to the two arc edges, and the accommodating groove has a square structure.

[0014] In some embodiments, the accommodating groove and the insulating plate group satisfy the relationship: 0.4≤c / h≤0.8, wherein, in the width direction of the cover plate, c is the width of the accommodating groove, and h is the width of the insulating plate group.

[0015] In some embodiments, 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 accommodating groove includes a first accommodating groove and a second accommodating groove; wherein, the first insulating plate is provided with a concave first accommodating groove on a side facing the cover plate, and the second insulating plate is provided with a concave second accommodating groove on a side facing the cover plate.

[0016] In some embodiments, the accommodating groove satisfies at least one of the following conditions: a groove depth H1 of the first accommodating groove is within a range of 0.5 mm to 2 mm; or a groove depth H2 of the second accommodating groove is within a range of 0.5 mm to 2 mm.

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

[0018] In some embodiments, a bottom wall of the receiving groove is provided with an air hole penetrating to the fourth surface of the insulating plate.

[0019] In some embodiments, a bottom wall of the accommodating tank is provided with a plurality of air holes, and the plurality of air holes include a first air hole and a second air hole, the first air hole is provided on the first insulating plate, and the second air hole is located on the second insulating plate.

[0020] In some embodiments, the plurality of air holes satisfy at least one of the following conditions: the plurality of first air holes on the first insulating plate are arranged in an array; or the plurality of second air holes on the second insulating plate are arranged in an array.

[0021] In some embodiments, the explosion-proof hole is directly opposite to the air vent.

[0022] In some embodiments, the cover plate is further provided with a first pole hole, a second pole hole, and a first liquid injection hole; one of the first pole hole and the second pole hole is a positive pole hole, the other of the first pole hole and the second pole hole is a negative pole hole, and the first liquid injection hole is located between the positive pole hole and the explosion-proof hole.

[0023] In a second aspect, the present application further provides a battery. The battery comprises a cell assembly, a housing, and an end cap assembly according to any one of the embodiments of the first aspect. The cell assembly is housed within the housing, the end cap assembly is connected to the housing, and the end cap assembly is electrically connected to the cell assembly.

[0024] In a third aspect, the present application further provides a battery pack comprising the battery described in the second aspect.

[0025] In a fourth aspect, the present application further provides a power system, which includes the battery pack described in the third aspect.

[0026] The present application sets a gap by providing an insulating plate group, so that when the internal air pressure of the battery increases, the gas can flow through the gap to the vicinity of the explosion-proof valve, and then explode the explosion-proof valve; at the same time, the positive projection of the explosion-proof valve on the insulating plate group coincides with the gap, so that when the internal air pressure of the battery increases, the gas flow rate and flow rate at the gap can quickly open the explosion-proof valve, thereby achieving the effect of rapid response of the explosion-proof valve; and the area of ​​the gap is within the above range, on the one hand, to ensure the smooth exhaust of the battery, and on the other hand, to ensure that after the explosion-proof valve explodes, a large amount of combustion residue will not be ejected from the gap and the explosion-proof hole, thereby reducing safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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.

[0028] FIG1 is a schematic exploded view of the structure of a battery according to some embodiments of the present application.

[0029] FIG2 is a schematic exploded view of the structure of an end cap assembly according to some embodiments of the present application.

[0030] FIG3 is a top view of an insulation plate assembly according to some embodiments of the present application.

[0031] FIG4 is a schematic cross-sectional view of the insulating plate assembly along the AA direction in FIG3 .

[0032] FIG5 is a top view of an insulation plate assembly housing an explosion-proof valve according to some embodiments of the present application.

[0033] FIG6 is a top view of the insulation plate assembly and explosion-proof valve separated according to some embodiments of the present application.

[0034] FIG7 is a schematic structural diagram of a battery pack according to some embodiments of the present application.

[0035] FIG8 is a schematic structural diagram of an electric power system according to some embodiments of the present application.

[0036] Explanation of the accompanying symbols: 100-battery, 10-end cover assembly, 20-cell assembly, 30-housing, 21-cell, 22-ear, 22A-positive ear, 22B-negative ear, 11-cover, 111-first surface, 112-second surface, 113-explosion-proof hole, 114A-first pole hole, 114B-second pole hole, 115-first liquid injection hole, 12-explosion-proof valve, 121-opening area, 13-insulating plate group, 131-third surface, 132-fourth surface, 133-accommodation groove, 134-vent, 134A-first vent, 134B-second vent, 135-gap, 136-second liquid injection hole, 137-storage groove, 13A-first insulating plate, 131A-third left surface, 132A-fourth left surface Surface, 13A1-first opposite end, 13A2-first connecting end, 13A3-third pole hole, 13A4-first accommodating groove, 13A5-first 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, 13B5-second notch, 14-pole, 14A-first pole, 14B-second pole, 200-battery pack, 300-power system, 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, the component 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, the component 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 in this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification are only for describing specific embodiments and are not intended to limit this application. The term "and / or" used in this application includes any combination or all combinations of one or more related listed items. The term "A / B" used in this application represents the ratio of parameter A to parameter B.

[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 housed within the housing 30. The end cap assembly 10 is connected to the housing 30, sealing an opening of the housing 30 and electrically connecting the end cap assembly 10 to the cell assembly 20.

[0042] For example, the appearance of the battery 100 can be a rectangular parallelepiped. In this application, the length direction of the battery 100 is defined as the X direction of the spatial coordinate system, the width direction of the battery 100 is defined as the Y direction of the spatial coordinate system, and the height direction (i.e., thickness direction) of the battery 100 is defined as the Z direction of the spatial coordinate system. For ease of understanding, the above directions are illustrated as an example. The direction in which the battery cell assembly 20 is placed from the opening into the housing 30 is the height direction of the battery 100, the long side of the opening is the length direction, and the short side of the opening 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 the battery cell assembly 20 can include two battery cells 21. The two battery cells 21 are stacked along the width direction (Y direction) 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 direction).

[0044] In some embodiments, 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 , and a pole 14 .

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

[0046] 2 , the cover plate 11 includes a first surface 111 and a second surface 112 facing each other in the thickness direction (Z direction). The first surface 111 faces the exterior of the end cap assembly 10, 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, which pass through the first and second surfaces 111 and 112.

[0047] In one embodiment of the present application, 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 direction) of the cover plate 11, the shortest distance from the two opposite ends of the cover plate 11 to the explosion-proof hole is the same.

[0048] Referring to FIG. 2 , the cover plate 11 is provided with two pole holes, namely 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. The injection holes are both circular in shape. In some embodiments of the present application, 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 , the first liquid injection hole 115 can be circular in shape. In some embodiments of the present application, the first liquid injection hole 115 can be located between the first electrode hole 114A and the explosion-proof hole 113; alternatively, the first liquid injection hole 115 can be located between the second electrode hole 114B and the explosion-proof hole 113. It is understood that the first liquid injection hole 115 needs to be located between the positive electrode hole and the explosion-proof hole 113.

[0050] The explosion-proof valve 12 is connected to the cover plate 11 and blocks the explosion-proof hole 113. In some embodiments of the present application, the explosion-proof valve 12 is connected to the second surface 112, and the connection between the explosion-proof valve 12 and the second surface 112 includes, but is not limited to, gluing, welding, or clamping. The explosion-proof valve 12 can also be disposed within the explosion-proof hole 113, specifically, the outer periphery of the explosion-proof valve 12 is connected to the inner wall of the explosion-proof hole 113.

[0051] In some embodiments of the present application, an indentation may be formed on the explosion-proof valve 12. The thickness of the explosion-proof valve 12 at the indentation may be less than the thickness at a location without the indentation. Providing the indentation can make the explosion-proof valve 12 more likely to burst. The present application does not specifically limit the shape and size of the indentation.

[0052] Referring to Figures 1 to 6 , the insulating plate assembly 13 has a gap, and at least a portion of the orthographic projection of the explosion-proof valve 12 on the insulating plate assembly 13 overlaps with the gap. This design allows the explosion-proof valve to be positioned in alignment with the gap, ensuring that gas generated within the battery can pass through the gap and reach the explosion-proof valve, shortening the time it takes for the gas to reach the valve.

[0053] In addition, in some embodiments, the explosion-proof valve has an opening area, and the area S of the gap is G1 and the area S of the opening area F1 Satisfy the relationship: 0.03≤S G1 / S F1≤0.15. Specifically, referring to FIG6 , the insulating plate group 13 includes a first insulating plate 13A and a second insulating plate 13B, with a gap 135 between the first insulating plate 13A and the second insulating plate 13B. The explosion-proof valve 12 has an opening area 121 (within the shaded area of ​​FIG6 ), and the area S of the gap 135 is G1 and the area S of the opening region 121 F1 Satisfy the relationship: 0.03≤S G1 / S F1 ≤0.15.

[0054] Specifically, explosion-proof valve 12 has a substantially oval indentation (or notch) in a circular shape. The area within the indentation (notch) is opening area 121. The orthographic projection of opening area 121 on the insulating panel is the same shape as that of explosion-proof valve 12, but their sizes are proportional, meaning the size of opening area 121 is less than or equal to the size of explosion-proof valve 12. For ease of calculation, opening area 121 can be defined as the orthographic projection area of ​​explosion-proof valve 12 on the insulating panel, or the orthographic projection area of ​​the explosion-proof hole on the insulating panel.

[0055] It should be noted that the area S of the gap 135 is G1 The area should be the area defined by the width of the insulating plate group 13 and the width of the gap (ie, the distance e between the first insulating plate 13A and the second insulating plate 13B).

[0056] Optionally, S G1 / S F1 It can be, but is not limited to, 0.03, 0.05, 0.07, 0.09, 0.11, 0.13, or 0.15.

[0057] When S G1 / S F1 When S is less than the lower limit of the above relationship (i.e., 0.03), it means that the area of ​​the gap 135 is too small, which will result in too small a gas flow at the gap 135. When the internal pressure of the battery 100 increases, the flow rate of the gas flowing through the gap 135 to the space between the explosion-proof valve 12 and the insulating plate assembly 13 will slow down, and the rapid response effect of the explosion-proof valve 12 cannot be achieved. G1 / S F1 When it is greater than the upper limit of the above relationship (i.e. 0.15), it means that the area of ​​the opening region 121 is too small, which will cause the explosion-proof valve 12 to burst open and fail to achieve a rapid pressure relief effect; or, it means that the gap 135 is too large, which will cause the gap 135 to fail to filter debris.

[0058] By setting the area of ​​the opening region 121 of the explosion-proof valve 12 to be larger than the area of ​​the gap 135, when the internal air pressure of the battery 100 increases, the gas flow rate and flow rate at the gap 135 can quickly open the explosion-proof valve 12, thereby achieving the effect of rapid response of the explosion-proof valve 12; and, the area of ​​the gap 135 is within a suitable range, so that after the explosion-proof valve 12 explodes, a large amount of combustion residue will not be ejected from the gap 135 and the explosion-proof hole 113, thereby reducing safety hazards.

[0059] In some embodiments, referring to Figure 2 , the insulating plate assembly 13 has a third surface 131 and a fourth surface 132 facing each other in its thickness direction (Z direction). The third surface 131 connects to the second surface 112. The insulating plate assembly 13 defines a receiving groove 133, the opening of which is distal to the fourth surface 132 of the insulating plate assembly 13. Specifically, the third surface 131 defines the receiving groove 133, and 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 to the fourth surface 132. The provision of the vent hole further ensures the exhaust efficiency of the explosion-proof valve.

[0060] Optionally, the insulating plate assembly 13 may be a flat plate structure, and its length and width may be the same as or slightly smaller than the length and width of 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.

[0061] Referring to Figure 2 , the insulating plate assembly 13 includes a first insulating plate 13A and a second insulating plate 13B disposed opposite each other along the length (X direction) of the cover plate 11. The first insulating plate 13A and the second insulating plate 13B together form 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 can be two separate insulating plates, so the width of the gap 135 between the first insulating plate 13A and the second insulating plate 13B is the distance between them. The length of the first insulating plate 13A and the length of the second insulating plate 13B can be the same or different.

[0062] Specifically, the advantage of providing two insulating plates (a first insulating plate 13A and a second insulating plate 13B) in the insulating plate group 13 in the present application is that when welding the two ends of the insulating plate group 13, the two insulating plates can share the force, so that the two insulating plates are evenly stressed without causing deformation in the middle and without affecting the exhaust inside the battery.

[0063] In some embodiments, the first insulating plate 13A may be a positive electrode insulating plate, and the second insulating plate 13B may be a negative electrode insulating plate. Of course, in other embodiments, the first insulating plate 13A may be a negative electrode insulating plate, and the second insulating plate 13B may be a positive electrode insulating plate. It will be appreciated that the positive electrode insulating plate is used to connect to the positive electrode of the battery cell assembly 20, and the negative electrode insulating plate is used to connect to the negative electrode of the battery cell assembly 20. This application does not specifically limit the first insulating plate 13A and the second insulating plate 13B.

[0064] In some embodiments, referring to FIG. 6 , the width of the gap between the first insulating plate 13A and the second insulating plate 13B (ie, e) is in the range of 0.5 mm to 3 mm.

[0065] In some embodiments, the first insulating plate 13A and the second insulating plate 13B have the same thickness. Referring to FIG. 4 , it can be understood that the first insulating plate 13A has a third left surface 131A and a fourth left surface 132A that face each other, and the second insulating plate 13B has a third right surface 131B and a fourth right surface 132B. 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.

[0066] In some embodiments, please refer to Figure 5, the accommodating groove 133 and the explosion-proof valve 12 satisfy the relationship: 0.3≤F1 / G1≤1, where F1 is the orthographic projection area of ​​the explosion-proof valve 12 on the insulating plate group 13, and G1 is the orthographic projection area of ​​the accommodating groove 133 on the cover plate 11.

[0067] Specifically, an explosion-proof groove is also provided on the second surface 112, and an explosion-proof hole 113 extends from the bottom wall of the explosion-proof groove to the first surface 111. Therefore, the size of the explosion-proof groove should be larger than the explosion-proof hole 113. In some embodiments of the present application, the shape of the explosion-proof groove and the explosion-proof hole 113 are the same, and the sizes of the two are proportional. The explosion-proof valve 12 is accommodated in the explosion-proof groove and is connected to the bottom wall and outer peripheral wall of the explosion-proof groove. With this design, the explosion-proof valve 12 can block the explosion-proof hole 113.

[0068] In some embodiments of the present application, explosion-proof valve 12 and accommodating groove 133 are directly opposite, and the orthographic projection of explosion-proof valve 12 on insulating plate assembly 13 is located within accommodating groove 133. Therefore, the orthographic projection area F1 of explosion-proof valve 12 on insulating plate assembly 13 is smaller than the orthographic projection area of ​​accommodating groove 133 on cover plate 11. Optionally, F1 / G1 can be, but is not limited to, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.

[0069] The advantage of the combination of the explosion-proof valve 12 and the accommodating groove 133 whose sizes fall within this range is that the size of the explosion-proof valve 12 (explosion-proof hole 113) can be controlled within an appropriate range, so that when the explosion-proof valve 12 explodes and releases pressure, the combustion residues ejected from the outside of the battery 100 shell 30 can be reduced; in addition, the explosion-proof valve 12 is smaller than the size of the accommodating groove 133, so that the explosion-proof valve 12 can be accommodated in the accommodating groove 133, thereby reducing the space occupied by the explosion-proof valve 12 in the thickness direction (Z direction) on the end cover assembly 10, thereby improving the utilization rate of the internal space of the battery 100.

[0070] In some embodiments, referring to FIG. 5 , the explosion-proof valve 12 has two opposite straight edges and two opposite arc edges, the two ends of the straight edges are respectively connected to the two arc edges, and the accommodating groove 133 is square.

[0071] Furthermore, the arc edge is semicircular, and in the thickness direction of the cover plate, the area F1 of the explosion-proof valve is: F1 = πR 2 +2Ra, the area G1 of the accommodating groove is: G1=bc, where R is the radius of the arc edge, a is the length of the straight edge, b is the length of the accommodating groove 133, and c is the width of the accommodating groove 133.

[0072] Specifically, the explosion-proof valve 12 may be elliptical in shape, so it has two opposite straight sides and two opposite arc sides. Accordingly, the area of ​​the explosion-proof valve 12 is calculated as the sum of the areas of two equal-sized semicircles and a quadrilateral.

[0073] In other embodiments, the accommodating groove 133 may also be in a rounded rectangle, an ellipse, or an ellipse-like shape, which is not limited in this application.

[0074] In some embodiments, please refer to Figure 3, the accommodating groove 133 and the insulating plate group 13 satisfy the relationship: 0.4≤c / h≤0.8, where, in the width direction (Y direction) of the cover plate 11, c is the width of the accommodating groove 133, and h is the width of the insulating plate group 13.

[0075] Specifically, in the width direction (Y direction) of the cover plate 11 , the width of the first accommodating groove 13A4 and the width of the second accommodating groove 13B4 should be the same, and both should be smaller than the width of the insulating plate group 13 .

[0076] In some embodiments of the present application, the two opposite sides of the accommodating groove 133 in the Y direction are at the same distance from the nearest corresponding insulating plate group 13. In other words, it can be understood that the accommodating groove 133 is located in the middle of the insulating plate group 13 in the Y direction.

[0077] When c / h is less than the lower limit of the aforementioned range, the width of the receiving groove 133 is relatively small, which can easily cause the explosion-proof valve 12 to extend beyond the receiving groove 133 and abut against the third surface 131, thereby increasing the thickness of the end cap assembly 10. When c / h is greater than the upper limit of the aforementioned range, the width of the receiving groove 133 is relatively large, which can result in the sidewalls of the receiving groove 133 being too weak in the Y direction.

[0078] Therefore, by designing a combination of the accommodating groove 133 and the insulating plate group 13 whose dimensions satisfy the above-mentioned relationship, the groove width of the accommodating groove 133 can be within an appropriate range. This ensures the structural strength of the insulating plate group 13 while ensuring that the explosion-proof valve 12 can be accommodated, thereby avoiding the end cover assembly 10 from being too thick.

[0079] In some embodiments, referring to FIG. 3 , the first insulating plate 13A further has a first opposing end 13A1 and a first connecting end 13A2, and the second insulating plate 13B further has 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 in the length direction (X direction), while the second opposing end 13B1 and the second connecting end 13B2 are located at opposite ends of the second insulating plate 13B in the length direction (X direction). The first opposing end 13A1 is adjacent to the second opposing end 13B1. The first opposing end 13A1 and the second opposing end 13B1 together enclose the accommodating groove 133.

[0080] Further, referring to Figure 3 , a third terminal hole 13A3 is defined at one end of the first insulating plate 13A (first connection end 13A2) distal from the second insulating plate 13B. A fourth terminal hole 13B3 is defined through one end of the second insulating plate 13B (second connection end 13B2) distal from the first insulating plate 13A. 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.

[0081] Referring to Figure 2 , the poles 14 include a first pole 14A and a second pole 14B. The structures of the first pole 14A and the second pole 14B are substantially identical. The poles 14 are disposed through the cover plate 11 and the insulating plate assembly 13. Specifically, the first pole 14A is disposed through the cover plate 11 and the first insulating plate 13A, while the second pole 14B is disposed through the cover plate 11 and the second insulating plate 13B.

[0082] In some embodiments, the first electrode 14A may be a positive electrode 14, and the second electrode 14B may be a negative electrode 14. Of course, in other embodiments, the first electrode 14A may be a negative electrode 14, and the second electrode 14B may be a positive electrode 14.

[0083] 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.

[0084] In some embodiments, please refer to Figures 3 and 4, the first insulating plate 13A is provided with a concave first accommodating groove 13A4 on the side facing the cover plate 11, and the second insulating plate 13B is provided with a concave second accommodating groove 13B4 on the side facing the cover plate 11. The first accommodating groove 13A4 and the second accommodating groove 13B4 constitute a accommodating groove.

[0085] 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.

[0086] Furthermore, the first accommodating groove 13A4 extends along the length direction (X direction) 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; the second accommodating groove 13B4 extends along the length direction (X direction) 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.

[0087] A first recessed receiving groove 13A4 is defined on the third left surface 131A. This recess 13A4 extends along the X-direction to the side of the first insulating plate 13A facing the second insulating plate 13B, forming a first notch 13A5. A second recessed receiving groove 13B4 is defined on the third right surface 131B. This recess 13B4 extends along the X-direction 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.

[0088] 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.

[0089] In some embodiments, referring to FIG. 4 , a groove depth H1 of the first receiving groove 13A4 is within a range of 0.5 mm to 2 mm; and / or a groove depth H2 of the second receiving groove 13B4 is within a range of 0.5 mm to 2 mm.

[0090] Specifically, the groove depth is the depth of the recess in the Z-direction. The depth of the first accommodating groove 13A4 and the depth of the second accommodating groove 13B4 can be the same or different. For example, the accommodating groove 133 has a uniform depth. Furthermore, the depth of the accommodating groove 133 should be less than the thickness of the insulating plate assembly 13.

[0091] Optionally, the depth of the first receiving groove 13A4 and / or the depth of the second receiving groove 13B4 can be, but is not limited to, 0.5 mm, 0.7 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, or 2 mm. When the depth of the first receiving groove 13A4 and / or the depth of the second receiving groove 13B4 is less than the lower limit of the above range, the receiving groove 133 is too shallow, and the explosion-proof valve 12 may protrude from the second surface 112. The receiving groove 133 cannot fully accommodate the explosion-proof valve 12, thereby increasing the thickness of the end cap assembly 10. When the depth of the first receiving groove 13A4 and / or the depth of the second receiving groove 13B4 is greater than the upper limit of the above range, the bottom wall of the receiving groove 133 is too thin and weak, and the receiving groove 133 is easily damaged when the end cap assembly is installed.

[0092] By setting the groove depth of the first accommodating groove 13A4 and the groove depth of the second accommodating groove 13B4 within the above-mentioned range, on the one hand, when the explosion-proof valve 12 protrudes from the second surface 112, space for accommodating the explosion-proof valve 12 can be provided; on the other hand, it can also ensure that the first insulating plate 13A and the second insulating plate 13B have sufficient thickness, thereby ensuring the structural strength of the two, and preventing bending or even breakage during the assembly of the battery 100.

[0093] Furthermore, the depth of the accommodating groove 133 is set within the above range, which can also form a gap between the bottom wall of the accommodating groove 133 and the explosion-proof valve 12, thereby preventing the explosion-proof valve 12 from exploding prematurely when the internal air pressure of the battery 100 does not reach the explosion threshold.

[0094] In some embodiments, both the first insulating plate 13A and the second insulating plate 13B are provided with ventilation holes 134 .

[0095] In some embodiments, referring to FIG. 3 , there are multiple air holes 134 , and the air holes 134 include first air holes 134A and second air holes 134B. The first air holes 134A are provided on the first insulating plate 13A, and the second air holes 134B are provided on the second insulating plate 13B. The number of the first air holes 134A and the second air holes 134B are the same.

[0096] Furthermore, the multiple air holes on the first insulating plate and / or the multiple air holes 134 on the second insulating plate are arranged in an array.

[0097] Specifically, the shapes and sizes of the first vent 134A and the second vent 134B can be the same or different. It is understood that when the first insulating plate 13A and the second insulating plate 13B are the same length, the shapes and sizes of the first vent 134A and the second vent 134B can be the same. When the first insulating plate 13A and the second insulating plate 13B are different lengths, the shapes and sizes of the first vent 134A and the second vent 134B can be different.

[0098] For example, the number of the first ventilation holes 134A can be three, and the number of the second ventilation holes 134B can also be three. The three first ventilation holes 134A are arranged at intervals along the Y direction, and the three second ventilation holes 134B are arranged at intervals along the Y direction.

[0099] Optionally, the outline shapes of the first ventilation hole 134A and the second ventilation hole 134B can both be a rounded rectangle or an ellipse.

[0100] By providing a plurality of air holes 134 on the insulating plate group 13, the plurality of air holes 134 and the gap 135 of the insulating plate group 13 can form a pressure relief channel, that is, when the internal air pressure of the battery 100 increases, the gas can pass through the air holes 134 and the gap 135 to gather near the explosion-proof valve 12, thereby bursting the explosion-proof valve 12; and the insulating plate group 13 with a plurality of air holes 134 can also form a filtering system, which can be blocked by the insulating plate group 13 to reduce the occurrence of combustion residues in the battery 100 being sprayed outside the battery 100.

[0101] In some embodiments, the orthographic projection area of ​​the explosion-proof valve 12 on the first insulating plate 13A accounts for 40% to 70% of the total projection area of ​​the explosion-proof valve 12 in the accommodating area, and the explosion-proof hole 113 and the air vent 134 are directly opposite.

[0102] Specifically, the explosion-proof valve 12 can be located in the center area of ​​the cover plate 11. It should be explained that since the cover plate 11 is rectangular, the explosion-proof valve 12 is located in the center area of ​​the cover plate 11 at both ends of the long side of the cover plate 11 and at both ends of the wide side of the cover plate 11.

[0103] In some embodiments of the present application, explosion-proof valve 12 is axially symmetrical. Therefore, when first insulating plate 13A and second insulating plate 13B have different lengths, the areas covered by first insulating plate 13A and second insulating plate 13B on explosion-proof valve 12 differ. Consequently, the opposite end of one of first insulating plate 13A and second insulating plate 13B may extend beyond the central axis of explosion-proof valve 12, while the opposite end of the other of first insulating plate 13A and second insulating plate 13B may not extend beyond the central axis of explosion-proof valve 12.

[0104] It can be understood that when the length of the first insulating plate 13A is greater than the length of the second insulating plate 13B, the area of ​​the explosion-proof valve 12 covered by the first insulating plate 13A is larger; conversely, when the length of the first insulating plate 13A is less than the length of the second insulating plate 13B, the area of ​​the explosion-proof valve 12 covered by the first insulating plate 13A is smaller.

[0105] In this combined state, when the internal pressure of the battery 100 is released, the two opposite ends (i.e., the opposite end beyond the center position of the explosion-proof valve 12 and the opposite end not beyond the center position of the explosion-proof valve 12) are squeezed by the internal air pressure at the same time. The opposite end beyond the center position of the explosion-proof valve 12 abuts against a larger area of ​​the explosion-proof valve 12 to form an opposite end eccentric to the explosion-proof valve 12, so that when the explosion-proof valve 12 is opened, the abutting end can help the explosion-proof valve 12 to open quickly; and when the explosion-proof valve 12 is in the open state, the air vents opened on the opposite ends can also help to filter internal combustion residues.

[0106] Optionally, the orthographic projection area of ​​the explosion-proof valve 12 on the first insulating plate 13A accounts for 40%, 45%, 50%, 55%, 60%, 65%, or 70% of the total projected area of ​​the explosion-proof valve 12 within the accommodation area. When the orthographic projection area ratio is less than the lower limit of the aforementioned range, it indicates that the first insulating plate 13A is relatively short and the second insulating plate 13B is relatively long, and the gap 135 between them cannot provide sufficient direct air pressure to burst the explosion-proof valve 12. When the orthographic projection area ratio is greater than the upper limit of the aforementioned range, it indicates that the second insulating plate 13B is relatively short and the first insulating plate 13A is relatively long, and the gap 135 between them cannot provide sufficient direct air pressure to burst the explosion-proof valve 12.

[0107] In some embodiments of the present application, the orthographic projection area of ​​the explosion-proof valve 12 on the first insulating plate 13A accounts for 50% to 60% of the total projection area of ​​the explosion-proof valve 12 in the accommodating area.

[0108] By setting the proportion of the orthographic projection area of ​​the explosion-proof valve 12 on the first insulating plate 13A to be within the above-mentioned range, the explosion-proof valve 12 can be distributed eccentrically on the first insulating plate 13A or the second insulating plate 13B, that is, the area directly facing the explosion-proof valve 12 and the first insulating plate 13A or the second insulating plate 13B is larger, so that when the first insulating plate 13A and the second insulating plate 13B are squeezed inside the battery 100, one of the insulating plates can have a larger contact area with the explosion-proof valve 12, thereby more vent holes 134 within the larger contact area, which is more conducive to the rapid opening of the explosion-proof valve 12.

[0109] In some embodiments, the present application further provides a battery pack. Referring to FIG7 , the battery pack 200 includes the battery 100 described in the above embodiment. Optionally, the battery pack 200 is a power battery, etc., which is not limited in the present application.

[0110] In some embodiments, the present application further provides a power system. Referring to FIG8 , the power system 300 includes the battery pack 200 described in the above embodiment. In some embodiments of the present application, the power system 300 includes a load (not shown) connected to the battery pack 200, which is used to power the load. Alternatively, the power system can be a vehicle or an energy storage power station, which is not limited in this application.

[0111] In the description of the embodiments of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do 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.

[0112] The above disclosure is merely an exemplary embodiment of the present application, and certainly cannot be used to limit the scope of rights of the present application. A person skilled in the art can understand that all or part of the processes of the above embodiments 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), the cover plate (11) comprising a first surface (111) and a second surface (112) which are opposite to each other in a thickness direction of the cover plate (11), and the cover plate (11) is provided with an explosion-proof hole (113) which passes through the first surface (111) and the second surface (112); an explosion-proof valve (12), the explosion-proof valve (12) being connected to the cover plate (11) and blocking the explosion-proof hole (113), and the explosion-proof valve (12) having an opening area (121); and An insulating plate group (13), the insulating plate group (13) comprising a third surface (131) and a fourth surface (132) facing each other in a thickness direction of the insulating plate group (13), the third surface (131) being close to the second surface (112), the insulating plate group (13) having a gap (135), at least a portion of the orthographic projection of the explosion-proof valve (12) on the insulating plate group (13) coinciding with the gap (135), and an area S of the gap (135) G1 and the area S of the opening area (121) F1 Satisfy the relationship: 0.03≤S G1 / S F1 ≤0.

15.

2. The end cap assembly (10) according to claim 1, 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), and the gap (135) is between the first insulating plate (13A) and the second insulating plate (13B).

3. The end cap assembly (10) according to claim 2, characterized in that: The width of the gap (135) is in the range of 0.5 mm to 3 mm.

4. The end cap assembly (10) according to claim 1, characterized in that: The insulating plate group (13) is provided with a receiving groove (133), the opening of the receiving groove (133) is away from the fourth surface (132) of the insulating plate group (13), and the orthographic projection of the explosion-proof valve (12) on the insulating plate group (13) is located in the receiving groove (133).

5. The end cap assembly (10) according to claim 4, characterized in that: The accommodating groove (133) and the explosion-proof valve (12) satisfy the relationship: 0.3≤F1 / G1≤1, wherein F1 is the orthographic projection area of ​​the explosion-proof valve (12) on the insulating plate group (13), and G1 is the orthographic projection area of ​​the accommodating groove (133) on the cover plate (11).

6. The end cap assembly (10) according to claim 4, characterized in that: The explosion-proof valve (12) has two opposite straight edges and two opposite arc edges, the two ends of the straight edge are respectively connected to the two arc edges, and the accommodating groove (133) has a square structure.

7. The end cap assembly (10) according to claim 4, characterized in that: The accommodating groove (133) and the insulating plate group (13) satisfy the relationship: 0.4≤c / h≤0.8, wherein, in the width direction of the cover plate (11), c is the width of the accommodating groove (133), and h is the width of the insulating plate group (13).

8. The end cap assembly (10) according to claim 4, 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 containing groove (133) comprises a first containing groove (13A4) and a second containing groove (13B4); The first insulating plate (13A) is provided with a first concave receiving groove (13A4) on one side facing the cover plate (11), and the second insulating plate (13B) is provided with a second concave receiving groove (13B4) on one side facing the cover plate (11).

9. The end cap assembly (10) according to claim 8, characterized in that: The accommodating groove (133) satisfies at least one of the following: The groove depth (H1) of the first containing groove (13A4) is in the range of 0.5 mm to 2 mm; or The groove depth (H2) of the second containing groove (13B4) is in the range of 0.5 mm to 2 mm.

10. The end cap assembly (10) according to claim 8, characterized in that: The first accommodating groove (13A4) extends along the length direction 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 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 claim 8, characterized in that: The bottom wall of the accommodating groove (133) is provided with an air hole (134) penetrating to the fourth surface (132).

12. The end cap assembly (10) according to claim 11, characterized in that: The bottom wall of the accommodating groove (133) is provided with a plurality of air holes (134), and the plurality of air holes (134) include a first air hole (134A) and a second air hole (134B), wherein the first air hole (134A) is provided on the first insulating plate (13A), and the second air hole (134B) is located on the second insulating plate (13B).

13. The end cap assembly (10) according to claim 12, characterized in that: The plurality of vent holes satisfy at least one of the following requirements: The plurality of first air holes (134A) located on the first insulating plate (13A) are arranged in an array; or The plurality of second air holes (134B) located on the second insulating plate (13B) are arranged in an array.

14. The end cap assembly (10) according to claim 11, characterized in that: The explosion-proof hole (113) is directly opposite to the air-permeable hole (134).

15. The end cap assembly (10) according to claim 1, characterized in that: The cover plate (11) is further provided with a first pole hole (114A), a second pole hole (114B), and a first liquid injection hole (115); one of the first pole hole (114A) and the second pole hole (114B) is a positive pole hole, the other of the first pole hole (114A) and the second pole hole (114B) is a negative pole hole, and the first liquid injection hole (115) is located between the positive pole hole and the explosion-proof hole (113).

16. A battery (100), characterized in that: It comprises a battery cell assembly (20), a shell (30), and an end cover assembly (10) as described in any one of claims 1 to 15, wherein the battery cell assembly (20) is accommodated in the shell (30), the end cover assembly (10) and the shell (30) are connected, and the end cover assembly (10) is electrically connected to the battery cell assembly (20).

17. A battery pack (200), characterized in that: Comprising the battery (100) as claimed in claim 16.

18. An electricity system (300), characterized in that: Comprising the battery pack (200) as claimed in claim 17.

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