Cap assembly and battery

Abstract

The utility model discloses a cap assembly and a battery, the cap assembly comprises a sealing structure, the sealing structure is provided with a sealing inner cavity, and a top cover, an anti-explosion sheet, a pore plate gasket and a pore plate are sequentially arranged in the sealing inner cavity from top to bottom; wherein the maximum distance between the top cover and the anti-explosion piece is D, and H is larger than or equal to 1.35 mm and smaller than 2.2 mm. The overall height of the cap assembly is reduced while the requirement for the explosion overturning height of the explosion-proof piece is met, the problems that an existing cap structure occupies a large battery height and a space needed by a battery cell is insufficient are solved, the cap assembly occupies a small space in the height direction of the battery, the battery cell is increased, and the battery capacity is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and particularly relates to a cap assembly and a battery. BACKGROUND

[0002] Lithium ion batteries have the advantages of high energy density, fast charging and discharging, long cycle life, no pollution, etc., and have been widely applied in the fields of portable electronic devices, communication, energy storage and electric vehicles.

[0003] The cylindrical battery includes a cap structure, a shell and a battery cell, etc. The cap structure includes a top cover, a sealing element, a burst disc, etc. The cap structure has many parts, and the height of the cap structure is high. In the case of a certain battery height, the cap structure occupies a large space in the height direction of the battery, and the space required by the battery cell is insufficient, which affects the battery capacity. UTILITY MODEL CONTENT

[0004] The cap assembly and the battery provided by the embodiments of the application solve the problem that the existing cap structure occupies a high height of the battery and the space required by the battery cell is insufficient.

[0005] In a first aspect, the embodiments of the application provide a cap assembly, comprising:

[0006] A sealing structure has a sealing inner cavity, and the sealing inner cavity is sequentially provided, from top to bottom, with a top cover, a burst disc, a hole plate gasket and a hole plate.

[0007] The maximum distance between the top cover and the burst disc is D, and 1.35mm≤H<2.2mm.

[0008] Optionally, the height of the top cover is H1, wherein 1.5mm≤H1≤2.05mm, and the height of the top cover refers to the distance between two parallel planes virtually abutting the two side surfaces of the top cover.

[0009] Optionally, the top cover includes a first cover body and a second cover body connected in sequence along the radial direction of the top cover, the cover body is attached to the burst disc, and the second cover body protrudes away from the side of the burst disc.

[0010] Optionally, the height of the burst disc is H2, wherein 0.65mm≤H2≤0.95mm.

[0011] Optionally, the burst disc includes a first body, a second body and a third body connected in sequence along the radial direction of the burst disc, and along the thickness direction of the burst disc, the first body, the second body and the third body are sequentially away from the top cover, and the first body is attached to the top cover.

[0012] Optionally, a distance between a plane where a side of the third body away from the top cover is located and a plane where a side of the second body away from the top cover is located is h, wherein 0.2mm≤h<0.35mm.

[0013] Optionally, the rupture disc further comprises a first inclined portion, the first inclined portion is located between the first body and the second body, the first inclined portion connects the first body and the second body, the top cover is provided with a first pressure relief hole, and a projection of the first pressure relief hole in a thickness direction of the top cover is located in a plane of the first inclined portion and the second body.

[0014] Optionally, the first inclined portion comprises a starting end and a terminal end, the starting end is closer to the first body than the terminal end, and the starting end is located between an inner wall of a side of the first pressure relief hole close to an edge of the top cover and the edge of the top cover on the top cover.

[0015] Optionally, the hole plate is provided with a second pressure relief hole, and the terminal end is located between an inner wall of the second pressure relief hole close to an edge of the hole plate and the edge of the hole plate on the hole plate.

[0016] Optionally, a diameter of a circle where the terminal end is located is S2, wherein

[0017] S2=S3+2a,

[0018] wherein S3 is an outer diameter of the second pressure relief hole;

[0019] a is a stamping edge width constant of the hole plate, and a value range of a.

[0020] Optionally, 7.7mm≤S3≤9.8mm and 0.3mm≤a≤0.5mm.

[0021] Optionally, the first inclined portion comprises a starting end and a terminal end, the starting end is closer to the first body than the terminal end, and a diameter of a circle where the starting end is located is S1,

[0022] 11mm≤S1≤12mm.

[0023] Optionally, a diameter of a circle where the terminal end is located is S2, 8.3mm≤S2≤10.8mm.

[0024] Optionally, a distance between a lower surface of the first body and a lower surface of the second body is N1, 0.15mm≤N1≤0.3mm.

[0025] Optionally, the hole plate gasket is provided with a second inclined portion, and the second inclined portion is connected to the first inclined portion in a fit manner.

[0026] Optionally, the hole plate is provided with a third inclined part, which is connected with the second inclined part.

[0027] Optionally, the sealing structure comprises:

[0028] The annular body;

[0029] The support is arranged at one end of the annular body, and the support is connected with the annular body.

[0030] The bottom support is connected with one side of the support away from the annular body along the radial direction of the annular body, and the annular body, the support and the bottom support enclose a sealed inner cavity.

[0031] The outer diameter of the support is D1, the inner diameter of the support is D2, and 2.6mm≤D1-D2≤3.8mm.

[0032] Optionally, 13.75mm≤D2≤14.95; or, 16.55mm≤D2≤17.75; or, 16.95mm≤D2≤18.15.

[0033] Optionally, the support comprises a first side surface and a second side surface arranged oppositely, the first side surface is located in the sealed inner cavity, the first side surface is a plane perpendicular to the axis of the annular body, the first side surface is sealingly connected with the rupture disc, and the second side surface is arranged obliquely.

[0034] In a second aspect, the embodiments of the present application further provide a battery comprising the cap assembly.

[0035] The cap assembly and the battery provided by the embodiments of the present application comprise a sealing structure, the top cover, the rupture disc, the hole plate gasket and the hole plate are sequentially arranged in the sealed inner cavity of the sealing structure from top to bottom, the maximum distance between the top cover and the rupture disc is D, and the value of D is between 1.35mm and 2.2mm, which meets the requirement of the rupture disc explosion and overturning height, reduces the overall height of the cap assembly, overcomes the problem that the existing cap structure occupies a higher height of the battery and the space required by the battery cell is insufficient, and the cap assembly occupies a small space in the height direction of the battery, which is beneficial to increasing the battery cell and improving the capacity of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0037] For a more complete understanding of the present application and the advantages thereof, reference is now made to the following description taken in connection with the accompanying drawings in which:

[0038] Figure 1 A side view of a battery provided by an embodiment of the present application.

[0039] Figure 2 A side view of a battery provided by an embodiment of the present application. Figure 1 A cross-sectional view of A-A in the above figure.

[0040] Figure 3 A cross-sectional view of B in the above figure. Figure 2 A partial enlarged view of C in the above figure.

[0041] Figure 4 A partial enlarged view of C in the above figure. Figure 3 A partial enlarged view of C in the above figure.

[0042] Figure 5 A perspective view of a top cover provided by an embodiment of the present application.

[0043] Figure 6 A cross-sectional view of a cap assembly provided by an embodiment of the present application after assembly.

[0044] Figure 7 A label view of a rupture disc provided by an embodiment of the present application.

[0045] Figure 8 A cross-sectional view of a cap assembly provided by an embodiment of the present application before assembly.

[0046] Reference signs in the drawings are:

[0047] 1, battery; 10, cap assembly; 20, shell; 21, neck-in structure; 22, flange; 30, battery cell;

[0048] 100, sealing structure; 110, sealing inner cavity; 120, annular body; 121, second sealing protrusion; 130, support table; 131, first sealing protrusion; 132, first side surface; 133, second side surface; 134, third side surface; 140, bottom support;

[0049] 200, top cover; 210, first cover body; 220, second cover body; 230, first pressure relief hole; 240, connecting portion;

[0050] 300, rupture disc; 310, first body; 320, second body; 330, third body; 340, first inclined portion; 341, starting end; 342, ending end; 350, first vertical plate;

[0051] 400, hole plate gasket; 410, second inclined portion;

[0052] 500, orifice plate; 510, second pressure relief hole; 520, third inclined section. Detailed Implementation

[0053] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0054] See Figure 1 , Figure 2 , Figure 3 , Figure 6 and Figure 8 This application provides a cap assembly 10 for use in batteries, such as cylindrical batteries. The cap assembly 10 includes a sealing structure 100 with a sealed inner cavity 110. Within the sealed inner cavity 110, from top to bottom, are arranged a top cover 200, an explosion-proof sheet 300, a perforated plate gasket 400, and a perforated plate 500. The maximum distance between the top cover 200 and the explosion-proof sheet 300 is D, where 1.35mm ≤ H < 2.2mm. The value of D can be 1.35mm, 1.40mm, 1.45mm, 1.55mm, 1.65mm, 1.75mm, 1.85mm, 1.95mm, 2.05mm, 2.15mm, 2.20mm, or other unlisted values.

[0055] In this embodiment, the maximum distance between the top cover 200 and the explosion-proof sheet 300 refers to the maximum vertical distance along the battery axis between the side of the top cover 200 near the explosion-proof sheet 300 and the side of the explosion-proof sheet 300 near the top cover 200.

[0056] In related technologies, the explosion-proof plate 300 is fixedly connected to the perforated plate 500, and the explosion-proof plate 300 has grooves. When the gas pressure inside the battery 1 reaches a certain level, the explosion-proof plate 300 separates from the perforated plate 500. Under the action of gas pressure, the explosion-proof plate 300 bulges outward from the side opposite to the perforated plate 500. As the gas pressure continues to increase, the grooves on the explosion-proof plate 300 burst open. Therefore, the height of the space between the explosion-proof plate 300 and the top cover 200 must be sufficient to meet the upward tilting height requirement of the explosion-proof plate 300; otherwise, the function of the explosion-proof plate 300 will be affected, potentially leading to battery explosion or other issues.

[0057] In this embodiment, the maximum distance D between the top cover 200 and the explosion-proof sheet 300 is designed to meet the upward space required after the explosion-proof sheet 300 explodes, thus minimizing the height of the cap assembly 10. With a fixed battery height, the smaller the height of the cap assembly 10, the larger the space that the battery cell 30 can occupy, which is beneficial for increasing battery capacity.

[0058] In some embodiments, referring to Figure 6 , the height of the top cover 200 is H1, where 1.5mm≤H1≤2.05mm. The height of the top cover 200 refers to the distance between the two parallel planes virtually abutting the two side surfaces of the top cover 200. The value of H1 can be 1.5mm, 1.6mm, 1.75mm, 1.7mm, 1.9mm, 2.0mm, 2.05mm, or other values not listed.

[0059] In the embodiments of the present application, the height of the top cover 200 is reduced to achieve the purpose of reducing the height of the cap assembly 10 and improve the space available for the battery cell 30. The size of the top cover 200 is designed to meet the space required for the explosion-proof disc 300 to flip up after explosion and the assembly requirements of the cap assembly 10.

[0060] In some embodiments, referring to Figure 5 , the top cover 200 includes a first cover body 210 and a second cover body 220 connected in sequence along the radial direction of the top cover 200. The first cover body 210 is annular, and the first cover body 210 is in contact with the explosion-proof disc 300. The second cover body 220 is located on the inner side of the first cover body 210, and the second cover body 220 is circular. The second cover body 220 protrudes from the side away from the explosion-proof disc 300. The second sealing protrusion 121 is in sealing abutment with the side of the first cover body 210 away from the second cover body 220. In the embodiments, the first cover body 210 and the second cover body 220 can be integrally formed by stamping. The height of the top cover 200 refers to the distance between the plane on which the side of the first cover body 210 in contact with the explosion-proof disc 300 is located and the plane on which the side of the second cover body 220 away from the explosion-proof disc 300 is located.

[0061] In some embodiments, referring to Figure 5 , the first cover body 210 further includes a connecting portion 240 located between the first cover body 210 and the second cover body 220. The inner diameter of the first cover body 210 is greater than the outer diameter of the second cover body 220, and the connecting portion 240 connects the first cover body 210 and the second cover body 220. A plurality of first pressure relief holes 230 are formed on the top cover 200 and are arranged at intervals along the circumferential direction of the top cover 200. The first pressure relief holes 230 are arranged on the connecting portion 240 and extend to the first cover body 210 and the second cover body 220.

[0062] In some embodiments, referring to Figure 6 and Figure 7, the height of the explosion-proof sheet 300 is H2, wherein 0.65 mm≤H2≤0.95 mm. The height of the explosion-proof sheet 300 refers to the distance between the plane where the side of the explosion-proof sheet 300 that is attached to the first cover body 210 is located and the plane where the side of the explosion-proof sheet 300 that is attached to the hole plate 500 is located. The value of H2 can be 0.65 mm, 0.72 mm, 0.74 mm, 0.75 mm, 0.80 mm, 0.87 mm, or other values not listed.

[0063] In the embodiments of the present application, the height of the explosion-proof sheet 300 is reduced to achieve the purpose of reducing the height of the cap assembly 10 and improve the space available for the battery cell 30. The size of the top cover 200 is designed to meet the space required for the explosion-proof sheet 300 to flip up after explosion and the assembly requirements of the explosion-proof sheet 300.

[0064] In some embodiments, referring to Figure 7 , the explosion-proof sheet 300 further includes a first body 310, a second body 320, and a third body 330 connected in sequence along the radial direction of the explosion-proof sheet 300. The first vertical plate 350 is arranged on the side of the first body 310 away from the second body 320. The first body 310 and the second body 320 are annular structures, and the third body 330 is circular. In the thickness direction of the explosion-proof sheet 300, the first body 310, the second body 320, and the third body 330 are sequentially away from the top cover 200. The first body 310 is attached to the top cover 200, i.e., the first body 310 is attached and connected to the first cover body 210. The second body 320 is provided with explosion-proof marks. The side of the third body 330 away from the top cover 200 is welded and connected to the hole plate 500. The second cover body 220 is coaxially arranged with the third body 330. The height of the explosion-proof sheet 300 refers to the vertical distance between the plane where the side of the first body 310 facing the top cover 200 is located and the plane where the side of the third body 330 away from the top cover 200 is located. The maximum distance between the top cover 200 and the explosion-proof sheet 300 refers to the vertical distance between the plane where the side of the second cover body 220 facing the explosion-proof sheet 300 is located and the plane where the side of the third body 330 facing the second cover body 220 is located.

[0065] In addition, referring to Figure 4 and Figure 7 , the explosion-proof sheet 300 further includes a first vertical plate 350 arranged on the side of the first body 310 away from the second body 320. The first vertical plate 350 is arranged around the edge of the top cover 200, and the first vertical plate 350 is spaced apart from the side of the top cover 200 away from the explosion-proof sheet 300 by a certain distance. The second sealing protrusion 121 of the sealing structure 100 can fill the end face of the first vertical plate 350 and the side of the top cover 200, ensuring the sealing effect.

[0066] In the embodiments of the present application, the first body 310, the second body 320 and the third body 330 of the explosion-proof sheet 300 are located at different heights, the material of the explosion-proof sheet 300 is increased, the material required for the overturning of the explosion-proof sheet 300 is provided, and the overturning height after the explosion of the explosion-proof sheet 300 is ensured.

[0067] In some embodiments, referring to Figure 6 and Figure 7 , the distance between the plane where the side of the third body 330 away from the top cover 200 is located and the plane where the side of the second body 320 away from the top cover 200 is located is h, where 0.2mm≤h<0.35mm. Wherein, h can be 0.2mm, 0.24mm, 0.27mm, 0.29mm, 0.30mm, 0.32mm, 0.34mm, 0.35mm or other values not listed.

[0068] In the embodiments of the present application, by reducing the distance between the plane where the side of the third body 330 away from the top cover 200 is located and the plane where the side of the second body 320 away from the top cover 200 is located, the height of the explosion-proof sheet 300 is reduced, and the purpose of reducing the height of the cap assembly 10 is achieved. The specifications of the first vertical plate 350, the first body 310 and the second body 320 can remain unchanged, and other associated components such as the hole plate gasket 400 and the hole plate 500 do not need to be changed, and the processing and assembly are simple.

[0069] In some embodiments, referring to Figure 4 , Figure 6 and Figure 7 , the explosion-proof sheet 300 further comprises a first inclined portion 340, the first inclined portion 340 is located between the first body 310 and the second body 320, the first inclined portion 340 connects the first body 310 and the second body 320, the top cover 200 is provided with a first pressure relief hole 230, and along the thickness direction of the explosion-proof sheet 300, the projection of the first pressure relief hole 230 is located in the plane of the first inclined portion 340 and the second body 320.

[0070] Compared with the related art, the first body 310 and the second body 320 are vertically connected, and the first body 310 can cover a part of the first pressure relief hole 230, affecting the pressure relief effect. In the embodiments of the present application, the first inclined portion 340 connects the first body 310 and the second body 320, the first inclined portion 340 avoids the position of the first pressure relief hole 230, ensures the pressure relief area of the first pressure relief hole 230, reduces the exhaust time, and improves the safety performance of the battery.

[0071] In some embodiments, referring to Figure 7The first inclined portion 340 comprises a starting end 341 and an ending end 342. The starting end 341 is closer to the first body 310 than the ending end 342. The starting end 341 is located between an inner wall of the first pressure relief hole 230 close to an edge of the top cover 200 and the edge of the top cover 200.

[0072] In the embodiments of the present application, the position of the starting end 341 of the first inclined portion 340 is located between the outer edge of the first pressure relief hole 230 and the outer edge of the top cover 200, so that the first inclined portion 340 avoids the first pressure relief hole 230 and ensures the pressure relief effect.

[0073] In some embodiments, referring to Figure 4 and Figure 6 , the hole plate 500 is provided with a second pressure relief hole 510, and the ending end 342 is located between an inner wall of the second pressure relief hole 510 close to an edge of the hole plate gasket 400 and the edge of the hole plate 500.

[0074] In the embodiments of the present application, the position of the ending end 342 of the first inclined portion 340 is located between the outer edge of the second pressure relief hole 510 and the outer edge of the hole plate 500, so that the first inclined portion 340 avoids covering the second pressure relief hole 510, ensures the exhaust effect of the hole plate 500, ensures the pressure relief effect, and improves the reliability of the battery.

[0075] In some embodiments, referring to Figure 6 and Figure 7 , the first inclined portion 340 comprises a starting end 341 and an ending end 342. The starting end 341 is closer to the first body 310 than the ending end 342. The diameter of the circle where the starting end 341 is located is S1, and 11mm≤S1≤12mm. The value of S1 can be 11mm, 11.3mm, 11.5mm, 11.6mm, 11.8mm, 12mm or other values not listed.

[0076] In the embodiments of the present application, the diameter of the explosion-proof sheet 300 is adapted to the shell 20, and the size of the explosion-proof sheet 300 is fixed. By limiting the diameter of the circle where the starting end 341 is located, the size of the first body 310 is indirectly determined, which is convenient for product design. When the size of S1 is less than 11mm, in order to avoid the explosion-proof sheet 300 blocking the first pressure relief hole 230, it is necessary to reduce the size of the first pressure relief hole 230, which affects the exhaust effect. If the size of S1 is greater than 12mm, the size of the first body 310 is reduced, the area of the first body 310 attached to the top cover 200 is reduced, and the assembly relationship of the first body 310 with other components is affected.

[0077] In some embodiments, referring to Figure 6 and Figure 7 , the diameter of the circle where the ending end 342 is located is S2, and S2 satisfies formula (1):

[0078] S2 = S3 + 2a (1);

[0079] wherein S3 is an outer diameter of the second pressure relief hole 510;

[0080] a is a punch edge width constant of the hole plate 500, and a is in a range of

[0081] In this embodiment, the punch edge width constant of the hole plate 500 refers to a distance between an outer edge of the second pressure relief hole 510 and an inner edge of the third inclined portion 520 on the hole plate 500.

[0082] In this embodiment, the position of the termination end 342 is determined according to the formula (1), so as to avoid the termination end 342 covering the second pressure relief hole 510 and ensure the pressure relief effect of the hole plate 500. In the case of unchanged specifications of the hole plate 500, the position of the termination end 342 is determined according to the formula (3), so as to facilitate the design of the rupture disc 300.

[0083] In some embodiments, 7.7mm≤S3≤9.8mm, 0.3mm≤a≤0.5mm.

[0084] In this embodiment, S3 is in a range of 7.7mm, 7.9mm, 8.2mm, 8.5mm, 8.9mm, 9.1mm, 9.5mm, 9.8mm or other values not listed. If S3 is less than 7.7mm, the hole diameter of the second pressure relief hole 510 is too small to meet the exhaust requirement, and if S3 is greater than 9.8mm, the hole diameter of the second pressure relief hole 510 is too large to affect the structural strength of the hole plate 500. The design of S3 can meet the specification requirement of the second pressure relief hole 510 on the hole plate 500, ensure the pressure relief effect, and meet the structural strength requirement of the hole plate 500.

[0085] In this embodiment, a is in a range of 0.3mm, 0.4mm, 0.5mm or other values not listed. The value of a is determined by the machining precision.

[0086] In some embodiments, referring to Figure 6 and Figure 7 the diameter of the circle where the termination end 342 is located is S2, and 8.3mm≤S2≤10.8mm. The value of S2 can be 8.4mm, 8.5mm, 8.7mm, 8.9mm, 9.2mm, 9.5mm, 9.7mm, 9.9mm, 10.2mm, 10.5mm, 10.8mm or other values not listed.

[0087] In the embodiment, if the value of the termination end 342 is small, the first inclined portion 340 is not easy to be processed and formed, and if the value of the termination end 342 is large, the second pressure relief hole 510 is covered, and the pressure relief effect is affected. In the embodiment of the application, the diameter of the circle where the termination end 342 is located is reasonably designed.

[0088] In some embodiments, referring to Figure 7 In some embodiments, 0.15mm≤N1≤0.3mm. Wherein, the value of N1 is 0.15mm, 0.18mm, 0.19mm, 0.22mm, 0.25mm, 0.28mm, 0.3mm or other values not listed.

[0089] For example, the angle between the first inclined portion 340 and the plane where the second body 320 is located is β, and β satisfies formula (2):

[0090] β=180°-arctan[N1 / S1-S2] (2),

[0091] Wherein, N1 is the distance between the lower surface of the first body 310 and the lower surface of the second body 320;

[0092] S1 is the diameter of the circle where the starting end 341 of the first inclined portion 340 is located;

[0093] S2 is the diameter of the circle where the termination end 342 of the first inclined portion 340 is located.

[0094] In the embodiment of the application, when the starting end 341 and the termination end 342 of the first inclined portion 340 and the distance between the lower surface of the first body 310 and the lower surface of the second body 320 are determined, the inclination angle of the first inclined portion 340 can be determined. By designing the distance between the lower surface of the first body 310 and the lower surface of the second body 320, the requirements of the blasting upward height of the explosion-proof disc 300 and the material stretching requirement of the first inclined portion 340 can be met.

[0095] In some embodiments, the hole plate gasket 400 is provided with a second inclined portion 410, and the second inclined portion 410 is connected with the first inclined portion 340.

[0096] In the embodiment of the application, referring to Figure 4 The hole plate gasket 400 is attached to the side of the explosion-proof disc 300 away from the top cover 200, and the shape of the hole plate gasket 400 is adapted to the shape of the explosion-proof disc 300. The second inclined portion 410 is connected with the first inclined portion 340, and the overall height of the cap assembly 10 is ensured.

[0097] In some embodiments, referring to Figure 4The hole plate 500 is provided with a third inclined portion 520 which is connected with the second inclined portion 410.

[0098] In the embodiment, the hole plate 500 is welded with the explosion-proof sheet 300, and the hole plate 500 and the explosion-proof sheet 300 clamp the hole plate gasket 400. The first inclined portion 340, the second inclined portion 410 and the third inclined portion 520 are connected in sequence, the explosion-proof sheet 300, the hole plate gasket 400 and the hole plate 500 are tightly connected, the height space occupied is small, and the overall height of the cap assembly 10 is ensured.

[0099] In some embodiments, referring to Figure 8 The sealing structure includes an annular body 120, a support 130 and a bottom support 140. The annular body 120 is a cylindrical structure. The support 130 is arranged at one end of the annular body 120, and the support 130 is connected with the annular body 120. The bottom support 140 is arranged along the radial direction of the annular body 120, and the bottom support 140 is connected with the side of the support 130 away from the annular body 120, so as to form a sealed inner cavity 110 together with the annular body 120, the support 130 and the bottom support 140. The outer diameter of the support 130 is D1, the inner diameter of the support 130 is D2, and 2.6mm≤D1-D2≤3.8mm. The value of D1-D2 can be 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.16mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm or other values not listed. In some embodiments, the annular body 120, the support 130 and the bottom support 140 are integrally formed by an injection molding process, which is simple to process. The annular body 120 is a cylindrical structure, and the inner side wall of the annular body 120 is provided with a second sealing protrusion 121. The support 130 is arranged at one end of the annular body 120, and the support 130 is connected with the annular body 120. The support 130 is sealingly connected with the side of the explosion-proof sheet 300 away from the top cover 200. The support 130 is provided with a first sealing protrusion 131, and the support 130 is sealingly connected with the explosion-proof sheet 300. The bottom support 140 is located between the hole plate 500 and the battery cell 30. Along the axial direction of the sealing structure 100, the cross-sectional shape of the second sealing protrusion 121 and the first sealing protrusion 131 on the cross section of the sealing structure 100 is triangular, trapezoidal, rectangular, arc-shaped or the like.

[0100] In the embodiment, the support 130 is compressed and deformed under the action of the buckling edge 22 and the necked structure 21. Under the size design of D1-D2, the height of the support 130 after extrusion deformation is small, and the support 130 will not extrude the battery cell 30. The sealing performance is met, and the height of the cap assembly 10 is reduced, thereby increasing the capacity of the battery.

[0101] In some embodiments, the value of D2 is different for different battery models. For example, 13.75mm≤D2≤14.95, the value of D2 can be 13.75mm, 13.80mm, 13.82mm, 13.86mm, 13.87mm, 13.91mm, 13.95mm or other values not listed. For example, 16.55mm≤D2≤17.75; the value of D2 can be 16.55mm, 16.80mm, 16.82mm, 16.86mm, 16.87mm, 16.91mm, 16.95mm, 17.72mm, 17.74mm, 17.75mm or other values not listed. For example, 16.95mm≤D2≤18.15. The value of D2 can be 16.95mm, 17.10mm, 17.22mm, 17.36mm, 17.57mm, 17.69mm, 17.95mm, 18.02mm, 18.10mm, 18.15mm or other values not listed. The parameter design of the sealing structure 100 meets the needs of different products, and has a wide range of applications.

[0102] In some embodiments, referring to Figure 8 , the support 130 includes a first side 132 and a second side 133 arranged opposite to each other, and the first side 132 is located in the sealing inner cavity 110. The first side 132 is a plane perpendicular to the axis of the annular body 120, that is, the first side 132 is arranged horizontally. The second side 133 is arranged obliquely, and the second side 133 is closer to the first side 132 at one end of the annular body 120 than at the other end. The inclination angle of the first side 132 is between 150° and 180°.

[0103] In the embodiments of the present application, referring to Figure 8 , the first side 132 of the support 130 is arranged horizontally, which is beneficial to the sealing connection of the rupture disc 300, and ensures the sealing effect of the sealing structure 100 and the rupture disc 300. The second side 133 of the support 130 is arranged obliquely, which is beneficial to the assembly of the sealing structure 100 and the shell 20, and facilitates the installation and disassembly of the sealing structure 100.

[0104] In some embodiments, referring to Figure 8 , the support 130 further includes a third side 134, one end of the third side 134 is connected to the end of the first side 132 away from the annular body 120, and the other end is connected to the side of the bottom support 140 close to the annular body 120. The third side 134 is arranged obliquely, and the end of the third side 134 close to the first side 132 is closer to the annular body 120 than the other end. The included angle between the third side 134 and the horizontal plane on which the bottom support 140 is located is between 150° and 180°.

[0105] In the embodiments of the present application, referring to Figure 8The third side surface 134 is arranged to be inclined. When the sealing structure 100 is processed, a liquid injection opening can be formed on the third side surface 134, which is beneficial to the flow of injection liquid and the injection molding of the sealing structure 100.

[0106] The battery 1 provided by the embodiments of the present application comprises the cap assembly 10, the shell 20 and the battery cell 30 of any one of the above embodiments.

[0107] In the embodiments of the present application, referring to Figure 1 、 Figure 2 and Figure 3 , the shell 20 has a cylindrical structure, one end of the shell 20 is open, the battery cell 30 is installed in the shell 20, the cap assembly 10 is sealingly connected with the shell 20, and the cap assembly 10 seals the opening.

[0108] For example, the shell 20 comprises a necked structure 21 and a flange 22. The end of the shell 20 extends inward along the radial direction of the shell 20 to form the flange 22. The flange 22 has a circular ring shape. The necked structure 21 is formed by concave inward along the radial direction of the shell 20 at a position of the shell 20 which is away from the flange 22 by a certain distance. The cap assembly 10 is fixed between the necked structure 21 and the flange 22. The sealing structure 100 is attached to the necked structure 21, the flange 22 and the part of the shell 20 between the necked structure 21 and the flange 22. The necked structure 21 and the flange 22 press the sealing structure 100 along the axial direction of the shell 20, so that the sealing structure 100 is sealingly connected with the top cover 200 and the explosion-proof sheet 300.

[0109] The battery 1 provided by the embodiments of the present application has the same technical effects as the cap assembly 10 of any one of the above embodiments, and thus the description is not repeated.

[0110] In the above embodiments, the description of each embodiment focuses on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0111] In the description of the present application, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more features.

[0112] The cap assembly and the battery provided by the embodiments of the present application are described in detail above, and the principles and implementation manners of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, the specific implementation manner and application range can be changed according to the idea of the present application. In conclusion, the content of the specification should not be understood as limiting the present application.

Claims

1. A cap assembly (10) characterized by, The application relates to a sealing structure (100) comprising a sealing inner cavity (110) in which a top cover (200), an explosion-proof sheet (300), a hole plate gasket (400) and a hole plate (500) are sequentially arranged from top to bottom. The maximum distance between the top cover (200) and the explosion-proof sheet (300) is D, and 1.35mm<=H<2.2mm. The height of the top cover (200) is H1, and 1.5mm<=H1<=2.05mm.

2. The cap assembly (10) according to claim 1, characterized in that The top cover (200) comprises a first cover body (210) and a second cover body (220) which are sequentially connected along the radial direction of the top cover (200), the cover body (210) is attached to the explosion-proof sheet (300), and the second cover body (220) protrudes away from one side of the explosion-proof sheet (300).

3. The cap assembly (10) according to claim 2, characterized in that The height of the explosion-proof sheet (300) is H2, and 0.65mm<=H2<=0.95mm.

4. The cap assembly (10) according to claim 1, characterized in that The explosion-proof sheet (300) comprises a first body (310), a second body (320) and a third body (330) which are sequentially connected along the radial direction of the explosion-proof sheet (300), the first body (310), the second body (320) and the third body (330) are sequentially away from the top cover (200) along the thickness direction of the explosion-proof sheet (300), and the first body (310) is attached to the top cover (200).

5. The cap assembly (10) according to any one of claims 1 to 4, characterized in that The distance between the plane where one side of the third body (330) away from the top cover (200) is located and the plane where one side of the second body (320) away from the top cover (200) is located is h, and 0.2mm<=h<0.35mm.

6. The cap assembly (10) according to claim 5, characterized in that The explosion-proof sheet (300) further comprises a first inclined part (340) which is located between the first body (310) and the second body (320) and connects the first body (310) and the second body (320), a first pressure relief hole (230) is arranged on the top cover (200), and the projection of the first pressure relief hole (230) is located in the plane of the first inclined part (340) and the second body (320) along the thickness direction of the top cover (200).

7. The cap assembly (10) according to claim 5, characterized in that The first inclined part (340) comprises a starting end (341) and an ending end (342), the starting end (341) is closer to the first body (310) than the ending end (342), and the starting end (341) is located between the inner wall of one side of the first pressure relief hole (230) on the top cover (200) close to the edge of the top cover (200) and the edge of the top cover (200).

8. The cap assembly (10) according to claim 7, characterized in that A second pressure relief hole (510) is arranged on the hole plate (500), and the ending end (342) is located between the inner wall of the second pressure relief hole (510) on the hole plate (500) close to the edge of the hole plate (500) and the edge of the hole plate (500).

9. The cap assembly (10) according to claim 8, characterized in that ​ 10. The cap assembly (10) according to claim 9, characterized in that A diameter of a circle where the terminal end (342) is located is S2, wherein, S2=S3+2a, S3 is an outer diameter of the second pressure relief hole (510); a is a constant of a punching edge width of the hole plate (500), and a is in a range of values.

11. The cap assembly (10) according to claim 10, characterized in that 7.7mm≤S3≤9.8mm, 0.3mm≤a≤0.5mm.

12. The cap assembly (10) according to claim 8, characterized in that The first inclined portion (340) includes a starting end (341) and a terminal end (342), the starting end (341) is closer to the first body (310) than the terminal end (342), a diameter of a circle where the starting end (341) is located is S1, 11mm≤S1≤12mm.

13. The cap assembly (10) according to claim 8, characterized in that A diameter of a circle where the terminal end (342) is located is S2, 8.3mm≤S2≤10.8mm.

14. The cap assembly (10) according to claim 7, characterized in that A distance between a lower surface of the first body (310) and a lower surface of the second body (320) is N1, 0.15mm≤N1≤0.3mm.

15. The cap assembly (10) according to claim 7, characterized in that The hole plate gasket (400) is provided with a second inclined portion (410), the second inclined portion (410) is connected with the first inclined portion (340) in a fit manner.

16. The cap assembly (10) according to claim 15, characterized in that The hole plate (500) is provided with a third inclined portion (520), the third inclined portion (520) is connected with the second inclined portion (410) in a fit manner.

17. The cap assembly (10) according to any one of claims 1 to 4, characterized in that A sealing structure (100) comprises: A ring-shaped body (120); A supporting table (130) is arranged at one end of the ring-shaped body (120), and the supporting table (130) is connected with the ring-shaped body (120); A bottom support (140) is connected with one side of the supporting table (130) away from the ring-shaped body (120) along a radial direction of the ring-shaped body (120), and the ring-shaped body (120), the supporting table (130) and the bottom support (140) enclose a sealed inner cavity (110); A diameter of the supporting table (130) is D1, and an inner diameter of the supporting table (130) is D2, 2.6mm≤D1-D2≤3.8mm.

18. The cap assembly (10) according to claim 17, characterized in that 13.75mm≤D2≤14.95; or, 16.55mm≤D2≤17.75; or, 16.95mm≤D2≤18.

15.

19. The cap assembly (10) according to claim 17, characterized in that The supporting table (130) comprises oppositely arranged first and second side surfaces (132 and 133), the first side surface (132) is located in the sealed inner cavity (110), the first side surface (132) is a plane perpendicular to an axis of the ring-shaped body (120), the first side surface (132) is sealingly connected with the explosion-proof sheet (300), and the second side surface (133) is arranged in an inclined manner.

20. A battery (1) characterized by A cap assembly (10) comprises any one of the cap assemblies (10) according to any one of claims 1 to 19.

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