CN219739112U - End cap assembly, battery and energy storage device - Google Patents

Abstract

The application provides an end cover assembly, a battery and an energy storage device. The end cap assembly includes: comprising the following steps: the pole comprises a pole body, a base and an end cap, the pole body is located between the base and the end cap, the cross-sectional area of the pole body is smaller than that of the base, the cross-sectional area of the pole body is smaller than that of the end cap, the sealing ring is sleeved on the periphery of the pole body and is in contact with the base, the sealing ring comprises a first end and a second end which are arranged oppositely along the circumferential direction, a gap is reserved between the first end and the second end, the first insulating part is abutted to one side, away from the base, of the sealing ring, and the gap between the first end and the second end is filled with the first insulating part. The end cover assembly provided by the application can solve the technical problems that a sealing ring in the prior art is easy to scratch a pole, so that the pole generates metal scraps and the like to fall to cause internal short circuit of a battery core, and the safety performance and the use reliability of a battery are affected.

Description

End cap assembly, battery and energy storage device

Technical Field

The application relates to the technical field of batteries, in particular to an end cover assembly, a battery and an energy storage device.

Background

The chargeable and dischargeable battery has the advantages of high energy density, high power density, multiple recycling times, long storage time and the like, and has wide application in the fields of electric automobiles, mobile equipment and the like.

The seal ring is an important seal structure in the battery end cap assembly. The current sealing washer generally needs to embolia the utmost point post along the direction of the base of utmost point post towards the utmost point post, and the in-process of colleting in utmost point post direction of height is gone up, and the sealing washer is scraped easily to the utmost point post to the frock of clamping the sealing washer to lead to producing substances such as metal fillings drop or remaining phenomenon on the utmost point post, when the metal fillings enter into inside the electric core, very easily lead to electric core internal short circuit and then fire explosion, very big influence the security performance and the reliability of use of battery.

Disclosure of Invention

The utility model provides an end cover assembly, a battery and an energy storage device, and aims to solve the technical problems that a sealing ring in the prior art is easy to scratch a pole, and further the pole is caused to fall off to cause internal short circuit of a battery core, and the safety performance and the use reliability of the battery are affected.

To solve the above problems, in a first aspect, the present utility model provides an end cap assembly comprising: the pole comprises a pole body, a base and an end cap, the pole body is located between the base and the end cap, the cross-sectional area of the pole body is smaller than that of the base, the cross-sectional area of the pole body is smaller than that of the end cap, the sealing ring is sleeved on the periphery of the pole body and is in contact with the base, the sealing ring comprises a first end and a second end which are arranged oppositely along the circumferential direction, a gap is reserved between the first end and the second end, the first insulating part is abutted to one side, away from the base, of the sealing ring, and the gap between the first end and the second end is filled with the first insulating part.

By arranging the first end and the second end with the gap, the sealing ring is provided with a fracture penetrating through the thickness of the sealing ring in the circumferential direction of the sealing ring. When the sealing ring is to be sleeved into the pole, the two ends of the sealing ring can be pulled open firstly, the distance between the first end and the second end is increased, and then the sealing ring is sleeved on the periphery of the pole body along the circumferential direction of the pole body and is contacted with the upper surface of the base. At this moment, under the effect of sealing washer self elasticity, first end and second end rebound and reset towards the axis of sealing washer, accomplish the assembly of sealing washer and utmost point post. When the sealing ring is to be taken out from the pole, the first end and the second end can be pulled open as well, and the sealing ring is taken down from the side wall surface of the pole body to finish the separation of the sealing ring and the pole. Compared with the traditional closed-loop sealing ring, on one hand, the sealing ring does not need to be sleeved with the pole along the direction of the end cap towards the base, so that scraping and rubbing of the sealing ring on the pole in the pole height direction is avoided, particularly scraping and rubbing of the side wall surface of the pole body, the joint of the pole body and the end cap and the like are avoided, the risk that substances such as metal scraps remain on the pole or fall off the pole is greatly reduced, the phenomenon that the battery cannot generate internal short circuit and fire explosion due to the falling metal scraps is ensured, and the safety performance and the use reliability of the battery are improved. On the other hand, the sealing ring is sleeved into the pole from the side wall surface of the pole, and can be directly sleeved into the area, close to the base, of the periphery of the pole body, so that the phenomenon that the sealing ring is clamped on the side wall surface of the pole body when sleeved from top to bottom is avoided, meanwhile, the assembly path of the sealing ring and the pole body is shortened, and the assembly efficiency of the sealing ring and the pole is greatly improved.

In one possible embodiment, the end face of the first end is a first inclined face arranged obliquely relative to the base, the end face of the second end is a second inclined face arranged obliquely relative to the base, and the gap is located between the first inclined face and the second inclined face. By arranging the end faces of the first end and the second end obliquely with respect to the lower surface of the seal ring, the relative area of the first end and the second end can be increased. Meanwhile, the fracture formed at the first end and the second end of the sealing ring is a fracture inclined relative to the pole body, when the sealing ring is subjected to external acting force due to vibration, shaking and the like, the sealing ring is always sleeved on the periphery of the pole body and is not easy to separate from the pole body, and the assembly strength of the sealing ring and the pole body is ensured.

In one possible embodiment, the first end is provided with a first extension part, the second end is provided with a second extension part, and the first extension part and the second extension part are stacked along the thickness direction of the sealing ring; or, the first extension part and the second extension part are arranged along the radial direction of the sealing ring. When the first extension part and the second extension part are overlapped in the thickness direction of the sealing ring, the displacement of the first end and the second end in the thickness direction of the sealing ring is limited, and the connection effect of the sealing ring and the upper surface of the base is ensured. When the first extending part and the second extending part are arranged along the radial direction of the sealing ring, the displacement of the first end and the second end in the radial direction of the sealing ring is limited, and the sleeving effect of the sealing ring on the periphery of the pole body is ensured. By providing the extension portions at the first end and the second end, respectively, the relative area of the first end and the second end can be further increased. Moreover, the seal ring is provided with a fracture formed at the first end and the second end, which is a fracture bent for a plurality of times. When the first insulating piece is injection-molded, the filling path of the injection molding liquid in the gap between the first end and the second end is longer, and the injection molding liquid can be used for filling the gap between the first end and the first end completely or partially. After the injection molding liquid is filled, the first insulating piece is connected with the first end and the second end, so that the sealing performance of the sealing ring in the end cover assembly can be brought into play.

In a possible embodiment, the surface of the first extension facing the second extension is further provided with at least one recess, and the surface of the second extension facing the first extension is further provided with at least one protrusion, which is at least partially located in the recess. By adding the concave-convex fitting structure between the first extending portion and the second extending portion, not only the relative area of the first end and the second end can be further increased, but also the displacement of the first end and the second end in the circumferential direction of the seal ring can be restricted. In addition, when the first extending portion and the second extending portion are stacked in the thickness direction of the sealing ring, the concave-convex matching structure plays a role in limiting displacement of the first end and the second end in the thickness direction of the sealing ring. When the first extending part and the second extending part are arranged along the radial direction of the sealing ring, the concave-convex matched structure plays a limiting role on the displacement of the first end and the second end in the radial direction of the sealing ring. Through increasing unsmooth complex structure between first extension and second extension, can further guarantee the assembly effect of sealing washer and utmost point post, more be favorable to exerting the sealing performance of sealing washer in the end cover subassembly.

In one possible embodiment, the end cap further includes a first limiting structure disposed around a side wall surface of the end cap, and the first limiting structure abuts against the first insulating member. Through setting up a limit structure, can increase the area of contact of end cap and first insulating part, improve the joint strength of utmost point post and first insulating part, prevent that the utmost point post from twisting.

In one possible embodiment, the outer diameter of the end cap is greater than the inner diameter of the seal ring. The sealing ring is not required to be sleeved into the pole from the side wall surface of the pole through the end cap, so that the design of the shape structure and the size of the end cap is more flexible, and the requirements of different battery structural designs can be met. For example, the end cap may be square, diamond, polygonal, oval, or other shapes in shape. The outer diameter of the end cap may be greater than the inner diameter of the seal ring. The first limit structure of limit structure on the end cap can be prolonged along the direction perpendicular to the axis of the pole body, for example, the length of the limit protrusion is prolonged or the depth of the limit groove is deepened, so that the contact area of the pole and the first insulating piece is further increased, and the connection strength and the anti-torsion performance of the pole and other parts are improved.

In a possible embodiment, the inner edge of the sealing ring is further provided with at least one recess, which is arranged at a distance from the gap between the first end and the second section in the circumferential direction of the sealing ring. When the sealing ring is sleeved on the periphery of the pole body and in interference fit with the end cover, one end of the outer edge of the sealing ring is contacted with the base, and the other end of the outer edge of the sealing ring is abutted by the end cover. Through setting up the breach at the inward flange of sealing washer, especially the one end that keeps away from the base at the sealing washer inward flange, can effectively reduce the resilience force that produces when sealing washer and end cover interference fit, improve the assembly reliability of end cover subassembly. When the notch is arranged at the outer edge of the sealing ring, the assembly tightness of the sealing ring and the end cover is affected, and electrolyte can remain at the notch when the battery electrolyte flows through the outer wall surface of the sealing ring. In addition, through set up the breach at the inward flange of sealing washer, can further increase the area of contact of sealing washer and first insulating part, improve the assembly strength of end cover subassembly. Further, in the circumferential direction of the sealing ring, the gap is arranged at intervals between the notch and the first and second ends, that is, the notch is not arranged at the fracture of the sealing ring, and the notch has gaps with the first and second ends. Through setting up the breach of sealing washer inward flange and the fracture interval of sealing washer, not only can reduce the influence of breach to the structural strength of first end and second end, can also avoid influencing the cooperation design of less clearance between first end and the second end, guaranteed the sealing washer and established the effect at the peripheral cover of utmost point post body.

In a possible implementation manner, the end cover assembly further comprises an end cover and a second insulating part, the end cover and the second insulating part are arranged in a stacked mode, the end cover is located between the first insulating part and the second insulating part, the end cover is provided with a first through hole for the pole body and the end cap to pass through, the second insulating part is provided with a second through hole for the pole body and the end cap to pass through, the sealing ring is located between the second through hole and the pole body, the sealing ring is in interference fit with the end cover, the second insulating part is located between the base and the end cover, the pole body passes through the second through hole and the first through hole, the end cap is in butt with the first insulating part, and the first insulating part is located in the gap of the end cover, the sealing ring and the pole three.

In a second aspect, the present application provides a battery comprising at least one end cap assembly as described above.

In a third aspect, the present application provides an energy storage device comprising at least one battery as described above.

In summary, through setting up first end and the second end that has the clearance at the sealing washer, the clearance of first end and second end is filled to first insulating part, not only provides a novel assembled mode that the sealing washer can embolia from the lateral wall face of utmost point post body, reduces the sealing washer and cuts and rub the utmost point post, solves and cuts and rubs the metal fillings that lead to and drop the inside technical problem that causes the short circuit of battery. In addition, the technical scheme of the application improves the assembly strength of the sealing ring and the pole, ensures the sealing effect of the sealing ring, avoids the phenomenon that the sealing ring is misplaced when the sealing ring is hung on the side wall surface of the pole body during assembly, reduces the leakage condition of the end cover assembly, and ensures the safety performance and the use reliability of the battery.

Drawings

In order to more clearly describe the embodiments of the present application or the technical solutions in the background art, the following description will describe the drawings that are required to be used in the embodiments of the present application or the background art.

FIG. 1 is a schematic structural diagram of an electric device according to an embodiment of the present application;

FIG. 2 is a schematic diagram of an energy storage device in the powered device shown in FIG. 1;

FIG. 3 is a schematic diagram of a battery in the energy storage device of FIG. 2;

FIG. 4 is an exploded view of the battery shown in FIG. 3;

FIG. 5 is a schematic illustration of the structure of the end cap assembly in the cell of FIG. 3;

FIG. 6 is an exploded schematic view of the end cap assembly of FIG. 5;

FIG. 7a is a schematic top view of the end cap assembly of FIG. 5;

FIG. 7b is a schematic cross-sectional view of the end cap assembly of FIG. 7a taken along the direction A-A;

FIG. 7c is an enlarged schematic view of region I of FIG. 7 b;

FIG. 8 is a schematic view of an assembled pole and seal ring according to an embodiment of the present application;

FIG. 9 is a schematic view of a post and seal ring structure provided in an embodiment of the present application;

FIG. 10 is a schematic structural view of a first seal ring according to an embodiment of the present application;

FIG. 11 is a schematic structural view of a second seal ring according to an embodiment of the present application;

FIG. 12 is a schematic structural view of a third seal ring according to an embodiment of the present application;

Fig. 13 is a schematic structural diagram of a fourth seal ring according to an embodiment of the present application;

fig. 14 is a schematic structural view of a fifth seal ring according to an embodiment of the present application;

FIG. 15 is a schematic structural view of a sixth seal ring according to an embodiment of the present application;

fig. 16 is a schematic structural view of a seventh seal ring according to an embodiment of the present application.

Reference numerals:

the power consumption device 400, the device body 410,

the energy storage device 300, the housing 310,

the battery 200 is provided with a battery,

end cap assembly 100, battery cell 110, housing 120, protective film 121, adapter plate 130,

the first insulating member 20 is provided with a first opening,

post 30, end cap 31, post body 32, base 33, limit groove 34, welding step 35, groove 36

Seal ring 40, first end 41, second end 42, first inclined surface 43a, second inclined surface 43b, first extension 44, second extension 45, recess 46, protrusion 47, notch 48, gap 49,

the end cap 50, the first through hole 51, the third through hole 52, the fifth through hole 53,

the second insulating member 60, the second through hole 61, the fourth through hole 62, the sixth through hole 63, the projection 64,

an explosion-proof valve 70, an explosion-proof valve protection sheet 71.

Detailed Description

Embodiments of the present application are described below with reference to the accompanying drawings.

Embodiments of the application provide an end cover assembly, a battery, an energy storage device and electric equipment.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an electric device 400 according to an embodiment of the application. The electric device 400 includes a device body 410 and an energy storage device 300, and the energy storage device 300 can supply power to each device in the device body 410 that needs to be powered, so as to meet the operation requirement of the electric device 400. The number of energy storage devices 300 may be one or more. When the number of the energy storage devices 300 is plural, the plurality of energy storage devices 300 may be connected in series, or in parallel, or in a mixture of series and parallel to achieve a larger capacity and power.

The electric equipment 400 may be a vehicle or an unmanned plane. Vehicles include, but are not limited to, electric only vehicles (Pure Electric Vehicle/Battery Electric Vehicle, PEV/BEV), hybrid vehicles (Hybrid Electric Vehicle, HEV), range-extended electric vehicles (Range Extended Electric Vehicle, REEV), plug-in hybrid vehicles (Plug-in Hybrid Electric Vehicle, PHEV), or new energy vehicles (New Energy Vehicle).

Referring to fig. 2, fig. 2 is a schematic structural diagram of an electric energy storage device 300 in the powered device 400 shown in fig. 1. The energy storage device 300 includes a housing 310 and a plurality of batteries 200, wherein the plurality of batteries 200 are electrically connected and are all located inside the housing 310, and can be protected from the external environment by the housing 310. In this embodiment, one energy storage device 300 includes a plurality of batteries 200. The plurality of batteries 200 are arranged at intervals. The plurality of batteries 200 may be connected in series, or in parallel, or a mixture of series and parallel to achieve a larger capacity and power.

Referring to fig. 3 and 4, fig. 3 is a schematic structural view of the battery 200 of fig. 2, and fig. 4 is an exploded schematic view of the battery 200 of fig. 3.

Wherein the battery 200 is a secondary battery. Such as nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid (or lead-storage) batteries, lithium-ion batteries, polymer lithium-ion batteries, and the like. In other embodiments, the battery 200 may also be a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, or a sodium ion battery, or a magnesium ion battery, etc.

In this embodiment, the battery 200 is a rectangular parallelepiped. In other embodiments, the battery 200 may also be cylindrical or other shapes. The battery 200 comprises an end cover assembly 100, a battery cell 110, a switching sheet 130 and a shell 120, wherein a protective film 121 can be adhered to the surface of the shell 120, the battery cell 110 is positioned inside the shell 120, the battery cell is protected from the external environment by the shell 120 and the protective film 121, and the connection between the battery cell 110 and the end cover assembly 100 is realized through the switching sheet 130.

Referring to fig. 5, 6, 7a, 7b and 7c, fig. 5 is a schematic structural view of the end cap assembly 100 in the battery 200 shown in fig. 3, fig. 6 is an exploded schematic view of the end cap assembly 100 shown in fig. 5, fig. 7a is a schematic plan view of the end cap assembly 100 shown in fig. 5, fig. 7b is a schematic sectional view of the end cap assembly 100 shown in fig. 7a in A-A direction, and fig. 7c is an enlarged schematic view of the region I shown in fig. 7 b. The end cap assembly 100 includes: the device comprises a first insulating part 20, a pole 30, a sealing ring 40, an end cover 50, a second insulating part 60 and an explosion-proof valve 70.

Referring to fig. 8 and 9, fig. 8 is a schematic structural view of the post 30 and the seal ring 40 after assembly, and fig. 9 is a schematic structural view of the post 30 and the seal ring 40 before assembly.

The pole 30 includes a pole body 32, a base 33 and an end cap 31, the end cap 31 and the base 33 are respectively located at opposite ends of the pole body 32, one end of the pole body 32 is connected with the base 33, and the other end of the pole body 32 is connected with the end cap 31. The cross-sectional area of the post body 32 is smaller than the cross-sectional area of the base 33, and the cross-sectional area of the post body 32 is smaller than the cross-sectional area of the end cap 31. That is, the projection of the pole body 32 onto the base 33 falls within the base 33, and the projection of the pole body 32 onto the end cap 31 falls within the end cap 31. Wherein the cross-sectional area is a cross-sectional area taken along a plane parallel to the base 33. In the present embodiment, the height of the base 33 and the end cap 31 is smaller than the height of the pole body 32. By providing the base 33 and end cap 31 to be less than the height of the post body 32, the space occupation of the base 33 at the end cap assembly 100 can be reduced, and the volumetric energy density of the battery 200 can be increased.

A first limiting structure is disposed around the side wall surface of the end cap 31, and the first limiting structure abuts against the first insulating member 20. The first limiting structure may be a limiting protrusion or a limiting groove. Illustratively, the first limiting structure is a limiting groove 34. By arranging the first limiting structure, the contact area between the end cap 31 and the first insulating member 20 can be increased, the connection strength between the pole 30 and the first insulating member 20 can be improved, and the pole 30 can be prevented from twisting. A welding step 35 is also provided at the end of the end cap 31 remote from the base 33. Through setting up welding step 35, be convenient for weld frock and fix +, reduce the impact force to post 30 when welding, influence the structural reliability and the assembly strength of end cover assembly 100 of post 30. The second limiting structure is disposed around the side wall of the pole body 32, and the second limiting structure is abutted to the first insulating member 20. The second limiting structure may be a limiting protrusion or a recess. Illustratively, as shown in fig. 7c, the second spacing structure is a groove 36. By arranging the second limiting structure, the contact area between the pole body 32 and the first insulating member 20 can be further increased, the connection strength between the pole 30 and the first insulating member 20 can be improved, and the torsion preventing performance of the pole 30 can be improved.

The seal ring 40 is sleeved on the periphery of the pole body 32 and contacts with the upper surface of the base 33. The seal ring 40 provides insulation and sealing in the end cap assembly 100. The seal ring 40 includes a first end 41 and a second end 42 disposed circumferentially opposite each other, the first end 41 and the second end 42 having a gap 49. By providing the first end 41 and the second end 42 with a gap 49, the sealing ring 40 is provided with a break through the thickness of the sealing ring 40 in the circumferential direction of the sealing ring 40. When the sealing ring 40 is to be sleeved into the pole 30, the two ends of the sealing ring 40 can be pulled apart to increase the distance between the first end 41 and the second end 42, and then the sealing ring 40 is sleeved on the periphery of the pole body 32 along the circumferential direction of the pole body 32 and contacts with the upper surface of the base 33. At this time, under the action of the elastic force of the seal ring 40, the first end 41 and the second end 42 rebound towards the axis of the seal ring 40, so as to complete the assembly of the seal ring 40 and the pole 30. When the seal ring 40 is to be removed from the pole 30, the first end 41 and the second end 42 can be pulled apart, and the seal ring 40 can be removed from the side wall surface of the pole body 32 to separate the seal ring 40 from the pole 30. Compared with the closed-loop sealing ring in the prior art, on one hand, the sealing ring 40 does not need to be sleeved into the pole 30 along the direction of the end cap 31 towards the base 33, so that the scraping and rubbing of the sealing ring 40 on the pole 30 in the process of sleeving the pole 30 in the height direction is avoided, particularly, the scraping and rubbing of the side wall surface of the pole body 32, the connecting position of the pole body 32 and the end cap 31 and the like are avoided, the risk that substances such as metal scraps remain on the pole 30 or fall from the pole 30 is greatly reduced, the phenomenon that the battery 200 is not internally shorted and exploded due to falling metal scraps is avoided, and the safety performance and the use reliability of the battery 200 are improved. On the other hand, the sealing ring 40 of the application is sleeved into the pole 30 from the side wall surface of the pole 30, and can be directly sleeved into the area, close to the base 33, of the periphery of the pole body 32, so that the phenomenon that the sealing ring 40 is clamped on the side wall surface of the pole body 32 when sleeved from top to bottom is avoided, meanwhile, the assembly path of the sealing ring 40 and the pole body 32 is shortened, and the assembly efficiency of the sealing ring 40 and the pole 30 is greatly improved. Meanwhile, the sealing ring 40 is sleeved into the pole 30 from the side wall surface of the pole 30 without passing through the end cap 31, so that the design of the shape structure and the size of the end cap 31 is more flexible, and the requirements of different structural designs of the battery 200 can be met. For example, the shape of the end cap 31 may be square, diamond, polygonal, oval, or other shapes. The outer diameter of the end cap 31 may be greater than the inner diameter of the seal ring 40. The first limiting structure on the end cap 31 may be extended in a direction perpendicular to the axis of the pole body 32, for example, by lengthening the length of the limiting protrusion or deepening the depth of the limiting groove 34, so as to further increase the contact area between the pole 30 and other components (such as the first insulating member 20), and improve the connection strength and anti-torsion performance of the pole 30 and other components.

In the embodiment of the present application, the gap 49 between the end face of the first end 41 and the end face of the second end 42 is 0.01mm to 0.5mm. The gap 49 here refers to the shortest distance between the end faces. When the first end 41 and the second end 42 are in interference fit, the first end 41 and the second end 42 of the sealing ring 40 are difficult to separate, and the efficiency of sleeving the sealing ring 40 into the pole 30 from the side wall surface of the pole body 32 is affected. When the gap 49 between the end face of the first end 41 and the end face of the second end 42 is greater than 0.5mm, the seal ring 40 has a larger fracture between the first end 41 and the second end 42, which not only increases the risk of the seal ring 40 separating from the sidewall surface from the post body 32, but also makes the sealing performance of the seal ring 40 at the fracture worse. When the gap 49 between the end face of the first end 41 and the end face of the second end 42 is in the range of 0.01 mm-0.5 mm, the sealing ring 40 can be sleeved from the side wall face of the pole body 32, and the gap 49 between the first end 41 and the second end 42 is smaller after the first end 41 and the second end 42 are rebound and reset, so that the sealing performance of the sealing ring 40 in the end cover assembly 100 is ensured.

In an embodiment of the present application, the inner diameter dimension of the seal ring 40 is greater than or equal to the outer diameter dimension of the post body 32. When the inside diameter size of the sealing ring 40 is smaller than the outside diameter size of the pole body 32, the sealing ring 40 is sleeved on the periphery of the pole body 32 along the circumferential direction of the pole body 32, the sealing ring 40 is propped up by the pole body 32, the first end 41 and the second end 42 are difficult to rebound and reset along the axis of the sealing ring 40, the sealing ring 40 is not only deformed under force, but also the gap 49 between the first end 41 and the second end 42 is enlarged, and the assembly effect of the sealing ring 40 and the pole 30 is greatly affected.

Further, the inner diameter dimension of the seal ring 40 is slightly greater than or equal to the outer diameter dimension of the post body 32. When the inside diameter size of the sealing ring 40 is far greater than the outside diameter size of the pole body 32, the sealing ring 40 is sleeved on the periphery of the pole body 32, when external acting forces such as vibration are received, the sealing ring 40 is deviated and swayed, the circle center of the sealing ring 40 and the circle center of the pole body 32 are deviated greatly, the sealing ring is easily hung in the groove 36 on the pole body 32, the assembly effect of the sealing ring 40 and the pole body 32 is affected, the air tightness of the end cover assembly 100 is further poor, the phenomenon of leakage of the battery 200 occurs, and the safety performance of the battery 200 is affected. Illustratively, the difference between the inner diameter dimension of the seal ring 40 and the outer diameter dimension of the post body 32 is 1mm or less. The concentricity of the seal ring 40 and the pole 30 ranges from 0mm to 0.15mm (including the end points of 0mm and 15 mm). The concentricity refers to the distance between the center of the seal ring 40 and the center of the pole body 32. The greater concentricity indicates a greater degree of deflection of the seal ring 40 and the post body 32. By setting the inner diameter of the seal ring 40 to be slightly larger than or equal to the outer diameter of the pole body 32, the seal ring 40 is not deformed after being sleeved on the periphery of the pole body 32, a smaller gap 49 is formed between the first end 41 and the second end 42, the seal ring 40 and the pole body 32 are ensured to have smaller concentricity, the offset degree of the seal ring 40 and the pole 30 is greatly reduced, and therefore the sealing performance of the seal ring 40 in the end cover assembly 100 is more favorably exerted.

In the embodiment of the present application, the inner edge of the sealing ring 40 is further provided with at least one notch 48, and the at least one notch 48 is spaced apart from a gap 49 between the first end 41 and the second end 42 in the circumferential direction of the sealing ring 40. When the sealing ring 40 is sleeved on the periphery of the pole body 32, and the sealing ring 40 is in interference fit with other components (such as the end cover 50), one end of the outer edge of the sealing ring 40 is in contact with the base 33, and the other end of the outer edge of the sealing ring 40 is abutted by the other components. By providing the notch 48 at the inner edge of the seal ring 40, especially at the end of the inner edge of the seal ring 40 away from the base 33, the rebound force generated when the seal ring 40 is in interference fit with other components can be effectively reduced, and the assembly reliability of the end cover assembly 100 can be improved. When the notch 48 is provided at the outer edge of the seal ring 40, not only will the fitting tightness of the seal ring 40 with other components be affected, but also electrolyte may be caused to remain at the notch 48 when the electrolyte of the battery 200 flows through the outer wall surface of the seal ring 40. In addition, by providing the notch 48 at the inner edge of the seal ring 40, the contact area between the seal ring 40 and other components (such as the first insulating member 20) can be further increased, and the assembly strength of the end cap assembly 100 can be improved. Further, in the circumferential direction of the seal ring 40, the gap 48 is spaced apart from the gap 49 between the first end 41 and the second end 42, that is, the gap 48 is not provided at the break of the seal ring 40, and the gap 48 has the gap 49 with both the first end 41 and the second end 42. Through setting up the breach 48 of sealing washer 40 inner edge and the fracture interval of sealing washer 40, not only can reduce the influence of breach 48 to the structural strength of first end 41 and second end 42, can also avoid influencing the cooperation design of less clearance 49 between first end 41 and the second end 42, guaranteed the effect is established at the peripheral cover of utmost point post body 32 to sealing washer 40.

The shape of the end cap 50 may be square or circular or other shape, with the end cap 50 being square in shape, for example. The end cap 50 is provided with a first through hole 51 for passing the post body 32 therethrough, a third through hole 52 for connecting the explosion-proof valve 70, and a fifth through hole 53 for filling. The through-hole area of the first through-hole 51 is greater than the cross-sectional areas of the post body 32 and the end cap 31 and less than the cross-sectional area of the base 33 to limit movement of the post body 32 out of the first through-hole 51 in a direction of the end cap 50 away from the second insulator 60. Wherein the cross-sectional area is a cross-sectional area taken along a plane parallel to the base 33. The explosion-proof valve 70 is connected to the third through hole 52, and an explosion-proof valve protection sheet 71 is further provided on the upper surface of the explosion-proof valve 70 to protect the explosion-proof valve 70 from the external environment.

The shape of the second insulator 60 may be square or circular or other shape, and the shape of the second insulator 60 is the same as the shape of the end cap 50. Illustratively, the shape of the second insulator 60 and the shape of the end cap 50 are square. The second insulator 60 is stacked with the end cap 50. The second insulator 60 is provided with a second through hole 61 for passing the post body 32 therethrough, a fourth through hole 62 communicating with the third through hole 52, and a sixth through hole 63 communicating with the fifth through hole 53. The second through hole 61 has a through hole area greater than the cross-sectional areas of the post body 32 and the end cap 31 and less than the cross-sectional area of the base 33 to limit movement of the post body 32 out of the second through hole 61 in the direction of the second insulator 60 toward the end cap 50. Wherein the cross-sectional area is a cross-sectional area taken along a plane parallel to the base 33.

Further, the connection effect between the second insulating member 60 and the end cap 50 can be enhanced by the reinforcing structure. The reinforcing structure may be a mating structure of protrusions and depressions. The dimples/protrusions are located on the side of the second insulator 60 facing the end cap 50 and the protrusions/dimples are located on the side of the end cap 50 facing the second insulator 60. Illustratively, the second insulator 60 is provided with a protrusion 64, and accordingly, the end cap 50 is provided with a recess (not shown) for mating therewith, the protrusion 64 and the recess cooperating with each other to enhance the connection between the second insulator 60 and the end cap 50.

The first insulating member 20 is used for filling gaps among the end cover 50, the sealing ring 40 and the pole 30, and has positioning and fixing functions on the pole 30, and meanwhile, the insulating performance between the pole 30 and the end cover 50 is ensured. Illustratively, during the assembly process of the end cap assembly 100, the base 33 is located on the lower surface of the second insulating member 60, the sealing ring 40 is sleeved on the periphery of the pole body 32 from the end cap 31 to the base 33, the pole body 32 and the end cap 31 sequentially pass through the second through hole 61 of the second insulating member 60 and the first through hole 51 of the end cap 50, and then the assembled semi-finished end cap 50 is put into an injection mold for fixing, and the injection molding of the first insulating member 20 is performed. When the first insulating member 20 is injection-molded, one end portion of the end cap 50 is pressed against the upper surface of the outer edge of the seal ring 40, so that a certain abutment force is formed against one end of the outer edge of the seal ring 40, and the injection-molding liquid flows into and seals the gaps among the end cap 50, the seal ring 40 and the pole 30.

In the embodiment of the application, when the injection molding liquid flows to the area of the end cap 31, the injection molding liquid can be filled into the limit groove 34 arranged on the side wall surface of the end cap 31, so as to increase the contact area between the first insulating member 20 and the end cap 31, ensure the connection reliability of the first insulating member 20 and the pole 30, and improve the anti-torsion performance of the pole 30. Further, the upper surface of the first insulating member 20 may be flush with the upper surface of the end cap 31 but lower than the welding step 35 of the end cap 31, and the influence on the connection position of the first insulating member 20 and the pole body 32 may be reduced when the welding step 35 of the end cap 31 is welded with an external member.

In the embodiment of the application, when the injection molding liquid flows to the region of the pole body 32, the injection molding liquid can be filled into the groove 36 provided on the side wall surface of the pole body 32, so as to increase the contact area between the first insulating member 20 and the pole body 32, so that the first insulating member 20 is tightly connected with the pole body 32, the connection reliability of the first insulating member 20 and the pole 30 is ensured, and the anti-torsion performance of the pole 30 is improved. Meanwhile, the injection molding liquid is filled in the gap between the side wall surface of the pole body 32 and the side wall surface of the end cover 50, so that the tight connection between the end cover 50, the first insulating piece 20 and the pole 30 is realized. Of course, reinforcing structures (such as a shallow limit groove or a rough surface, not shown) may be further disposed on the side wall surface of the end cap 50 and the side wall of the pole body 32, so as to enhance the contact area between the end cap 50 and the first insulating member 20 and improve the connection strength.

Further, when the injection molding liquid continues to flow to the area below the groove 36 and reaches the sealing ring 40, the injection molding liquid can fill not only the gap between the side wall surface of the sealing ring 40 and the side wall surface of the pole body 32, but also the gap 49 between the first end 41 and the second end 42 of the sealing ring 40. When the filling path of the injection molding liquid in the gap 49 between the first end 41 and the second end 42 is long, particularly when a concave-convex reinforcing structure is provided between the first end 41 and the second end 42, the connection strength between the first end 41 and the second end 42 is relatively high, and the injection molding liquid can also partially fill the gap 49 between the first end 41 and the second end 42 and connect the first end 41 and the second end 42, so that the sealing performance of the seal ring 40 in the end cover assembly 100 is exerted. Wherein, the partial filling here refers to that the injection molding liquid fills the areas of the upper surfaces of the first end and the second end to connect the first end and the second end. When the filling path of the injection molding liquid in the gap 49 between the first end 41 and the second end 42 is shorter, the injection molding liquid can completely fill the gap 49 between the first end 41 and the second end 42, even the injection molding liquid can flow to the upper surface of the base, so that not only the connection between the first end 41 and the second end 42 is realized, but also the tight connection between the sealing ring 40 and the base 33 is realized, the connection strength between the sealing ring 40 and the pole 30 is enhanced, and the connection strength and the sealing performance of the end cover assembly 100 are ensured. Further, when at least one notch is provided at the end of the inner edge of the sealing ring 40 away from the base 33, the injection molding liquid can also be filled into the notch of the inner edge of the sealing ring 40, so as to further improve the connection strength between the first insulating member 20 and the sealing ring 40 and between the first insulating member 40 and the pole 30.

In the embodiment of the present application, the injection molding liquid may not only fill the gap between the end cap 50, the seal ring 40 and the pole 30, but also, but not limited to, fill the limit groove 34 provided by the end cap 31, the groove 36 provided by the pole body 32, the gap 49 between the first end 41 and the second end 42 of the seal ring 40, etc. After injection molding is completed, the first insulating member 20 is simultaneously abutted against the end cover 50, the sealing ring 40 and the pole 30, so that the sealing ring 40 and the pole 30 are matched more tightly and reliably. Therefore, the application not only provides a novel assembly mode in which the sealing ring 40 can be sleeved from the side wall surface of the pole body 32, but also reduces scraping and rubbing of the sealing ring 40 on the pole 30, and solves the technical problem that metal scraps caused by scraping and rubbing fall into the battery 200 to cause short circuit. In addition, the end cover assembly structure of the application also ensures the sealing effect of the sealing ring 40, avoids the phenomenon that the sealing ring 40 is misplaced when the sealing ring 40 is hung on the side wall surface of the pole body 32 during assembly, reduces the condition of air leakage and liquid leakage of the end cover assembly 100, and ensures the safety performance of the battery 200.

The specific construction of the seal ring 40 will be described below by way of several different embodiments.

First embodiment:

referring to fig. 10, fig. 10 is a schematic structural diagram (front view) of a first seal ring 40 according to an embodiment of the application.

In this embodiment, the seal ring 40 includes a first end 41 and a second end 42, the first end 41 and the second end 42 having a gap 49. The end face of the first end 41 and the end face of the second end 42 are both parallel to the thickness direction of the seal ring 40. That is, the end face of the first end 41 and the end face of the second end 42 are perpendicular to the lower surface of the seal ring 40. The gap 49 between the end face of the first end 41 and the end face of the second end 42 is 0.01mm to 0.5mm. The inner diameter of the seal ring 40 is slightly greater than or equal to the outer diameter of the post body 32. After the seal ring 40 is sleeved from the side wall surface of the pole body 32, the seal ring 40 is located at the periphery of the pole body 32 and is in contact with the upper surface of the base 33. When the first insulating member 20 is injection-molded, the filling path of the injection molding liquid in the gap 49 between the first end 41 and the second end 42 is short, and the injection molding liquid completely fills the gap 49 between the first end 41 and the first end 41, and may further fill the upper surface of the base 33. The gap 49 around the sealing ring 40 is filled with the injection molding liquid of the first insulating member 20, so that not only can the connection between the first end 41 and the second end 42 be realized, but also the tight connection between the sealing ring 40 and the base 33 can be realized, and the connection strength between the sealing ring 40 and the pole 30 can be enhanced.

Second embodiment:

referring to fig. 11, fig. 11 is a schematic structural diagram (front view) of a second seal ring 40 according to an embodiment of the application.

In this embodiment, the same contents as those of the first embodiment will not be described in detail, unlike the first embodiment, the end face of the first end 41 is a first inclined face 43a inclined with respect to the base 33, the end face of the second end 42 is a second inclined face 43b inclined with respect to the base 33, and the gap 49 between the first end 41 and the second end 42 is located between the first inclined face 43a and the second inclined face 43 b. That is, the shortest distance from the first inclined surface 43a to the second inclined surface 43b is 0.01mm to 0.5mm.

By disposing the end surfaces of the first end 41 and the second end 42 obliquely with respect to the lower surface of the seal ring 40, the opposing areas of the first end 41 and the second end 42 can be increased as compared with the first embodiment. In addition, the fracture formed at the first end 41 and the second end 42 of the sealing ring 40 is a fracture inclined relative to the pole body 32, when the sealing ring 40 receives external force due to vibration and shaking, the sealing ring 40 is always sleeved on the periphery of the pole body 32 and is not easy to separate from the pole body 32, so that the assembly strength of the sealing ring 40 and the pole body 32 is ensured.

Third embodiment:

referring to fig. 12, fig. 12 is a schematic structural diagram (front view) of a seal ring 40 according to an embodiment of the application.

In this embodiment, the same contents as those of the first embodiment will not be described again, and unlike the first embodiment, the first end 41 is provided with a first extension 44, and the second end 42 is provided with a second extension 45. The first extension 44 and the second extension 45 are stacked in the thickness direction of the seal ring 40. Illustratively, the first extension 44 is located above the second extension 45. The upper surface of the first extension 44 is coplanar with the upper surface of the sealing ring 40, and the lower surface of the second extension 45 is coplanar with the lower surface of the sealing ring 40. The sidewall surface of the first extension portion 44 has a gap 49 with the sidewall surface of the second end 42, the lower surface of the first extension portion 44 has a gap 49 with the upper surface of the second extension portion 45, and the sidewall surface of the second extension portion 45 has a gap 49 with the sidewall surface of the first end 41.

By providing the extension portions at the first end 41 and the second end 42, respectively, the relative area of the first end 41 and the second end 42 can be further increased as compared with the first embodiment. The first extending portion 44 and the second extending portion 45 are stacked along the thickness direction of the sealing ring 40, so that displacement of the first end 41 and the second end 42 in the thickness direction of the sealing ring 40 is limited, and the connection effect of the sealing ring 40 and the upper surface of the base 33 is ensured. Further, the seal ring 40 has a plurality of bending breaks formed at the first end 41 and the second end 42. When the first insulating member 20 is injection-molded, the injection molding liquid may fill the gap 49 between the first end 41 and the second end 42 in a longer path, and the injection molding liquid may fill the gap 49 between the first end 41 and the first end 41 completely or partially. After the injection molding liquid is filled, the first insulating member 20 connects the first end 41 and the second end 42, which is beneficial to exerting the sealing performance of the sealing ring 40 in the end cover assembly 100.

Fourth embodiment:

referring to fig. 13, fig. 13 is a schematic structural diagram (front view) of a fourth seal ring 40 according to an embodiment of the application.

In this embodiment, the same contents as those of the third embodiment will not be repeated, and unlike the third embodiment, the first extension portion 44 is further provided with at least one concave portion 46 recessed toward the lower surface of the sealing ring 40, the second extension portion 45 is further provided with at least one convex portion 47 protruding toward the lower surface of the sealing ring 40, and the convex portion 47 is at least partially located in the concave portion 46. By adding the concave-convex fit structure between the first extension portion 44 and the second extension portion 45, the relative area of the first end 41 and the second end 42 can be further increased, and the displacement of the first end 41 and the second end 42 in the circumferential direction of the sealing ring 40 is limited while the displacement of the first end 41 and the second end 42 in the thickness direction of the sealing ring 40 is limited, so that the assembly effect of the sealing ring 40 and the pole 30 is further ensured, and the sealing performance of the sealing ring 40 in the end cover assembly 100 is more facilitated to be exerted.

Fifth embodiment:

referring to fig. 14, fig. 14 is a schematic structural diagram (top view) of a fifth seal ring 40 according to an embodiment of the application.

In this embodiment, the same contents as those of the first embodiment will not be described again, and unlike the first embodiment, the first end 41 is provided with a first extension 44, and the second end 42 is provided with a second extension 45. The first extension 44 and the second extension 45 are disposed in alignment along the radial direction of the seal ring 40. Illustratively, the first extension 44 is located outboard of the second extension 45. The outer sidewall surface of the first extension 44 is coplanar with the outer sidewall surface of the seal ring 40, and the inner sidewall surface of the second extension 45 is coplanar with the inner sidewall surface of the seal ring 40. The end face of the first extension portion 44 has a gap 49 with the end face of the second end 42, the inner side wall face of the first extension portion 44 has a gap 49 with the outer side wall face of the second extension portion 45, and the end face of the second extension portion 45 has a gap 49 with the end face of the first end 41. Wherein, one side of the sealing ring 40 close to the axis of the sealing ring 40 is inner, and one side of the sealing ring 40 far away from the axis of the sealing ring 40 is outer.

By providing the extension portions at the first end 41 and the second end 42, respectively, the relative area of the first end 41 and the second end 42 can be further increased as compared with the first embodiment. Along the radial direction of the sealing ring 40, the first extending portion 44 and the second extending portion 45 are arranged in an aligned manner, so that the displacement of the first end 41 and the second end 42 in the radial direction of the sealing ring 40 is limited, and the sleeving effect of the sealing ring 40 on the periphery of the pole body 32 is ensured. Further, the seal ring 40 has a plurality of bending breaks formed at the first end 41 and the second end 42. When the first insulating member 20 is injection-molded, the injection molding liquid may fill the gap 49 between the first end 41 and the second end 42 in a longer path, and the injection molding liquid may fill the gap 49 between the first end 41 and the first end 41 completely or partially. After the injection molding liquid is filled, the first insulating member 20 connects the first end 41 and the second end 42, which is beneficial to exerting the sealing performance of the sealing ring 40 in the end cover assembly 100.

Sixth embodiment:

referring to fig. 15, fig. 15 is a schematic structural diagram (top view) of a sixth seal ring 40 according to an embodiment of the application.

In this embodiment, the same contents as those of the sixth embodiment will not be repeated, and unlike the sixth embodiment, the first extension portion 44 is further provided with at least one concave portion 46 recessed toward the lower surface of the seal ring 40, the second extension portion 45 is further provided with at least one convex portion 47 protruding toward the lower surface of the seal ring 40, and the convex portion 47 is at least partially located in the concave portion 46. By adding the concave-convex fit structure between the first extension portion 44 and the second extension portion 45, the relative area of the first end 41 and the second end 42 can be further increased, and the displacement of the first end 41 and the second end 42 in the radial direction of the sealing ring 40 is limited, and meanwhile, the displacement of the first end 41 and the second end 42 in the circumferential direction of the sealing ring 40 is limited, so that the assembly effect of the sealing ring 40 and the pole 30 is further ensured, and the sealing performance of the sealing ring 40 in the end cover assembly 100 is more facilitated to be exerted.

Seventh embodiment:

referring to fig. 16, fig. 16 is a schematic structural diagram (top view) of a seal ring 40 according to a seventh embodiment of the application.

In this embodiment, the same content as that of the fifth embodiment will not be described in detail, and unlike the fifth embodiment, the inner edge of the sealing ring 40 is further provided with at least one notch 48, and in the circumferential direction of the sealing ring 40, the at least one notch 48 is spaced from a gap 49 between the first end 41 and the second end 42. When the sealing ring 40 is sleeved on the periphery of the pole body 32, and the sealing ring 40 is in interference fit with other components (such as the end cover 50), one end of the outer edge of the sealing ring 40 is in contact with the base 33, and the other end of the outer edge of the sealing ring 40 is abutted by the other components. By providing the notch 48 at the inner edge of the seal ring 40, especially at the end of the inner edge of the seal ring 40 away from the base 33, the rebound force generated when the seal ring 40 is in interference fit with other components can be effectively reduced, and the assembly reliability of the end cover assembly 100 can be improved. When the notch 48 is provided at the outer edge of the seal ring 40, not only will the fitting tightness of the seal ring 40 with other components be affected, but also electrolyte may be caused to remain at the notch 48 when the electrolyte of the battery 200 flows through the outer wall surface of the seal ring 40. In addition, by providing the notch 48 at the inner edge of the seal ring 40, the contact area between the seal ring 40 and other components (such as the first insulating member 20) can be further increased, and the assembly strength of the end cap assembly 100 can be improved. Further, in the circumferential direction of the seal ring 40, the gap 48 is spaced apart from the gap 49 between the first end 41 and the second end 42, that is, the gap 48 is not provided at the break of the seal ring 40, and the gap 48 has the gap 49 with both the first end 41 and the second end 42. Through setting up the breach 48 of sealing washer 40 inner edge and the fracture interval of sealing washer 40, not only can reduce the influence of breach 48 to the structural strength of first end 41 and second end 42, can also avoid influencing the cooperation design of less clearance 49 between first end 41 and the second end 42, guaranteed the effect is established at the peripheral cover of utmost point post body 32 to sealing washer 40.

Of course, this embodiment is merely illustrative of one possible implementation of providing the notch 48 on the inner edge of the seal ring 40 of the present application, and the notch 48 may be adapted to the above-described embodiments or other embodiments consistent with the claimed application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of embodiments of the application, the meaning of "plurality" means two or more than two, unless specifically defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: there are three cases, a, B, a and B simultaneously. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like should be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally formed; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to specific circumstances.

Finally, it should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present application and not for limiting the same, and although the present application has been described in detail with reference to the above-mentioned preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made to the technical solution of the present application without departing from the spirit and scope of the technical solution of the present application.

Claims (10)

1. An end cap assembly, comprising: the pole comprises a pole body, a base and an end cap, the pole body is located between the base and the end cap, the cross-sectional area of the pole body is smaller than that of the base, the cross-sectional area of the pole body is smaller than that of the end cap, the sealing ring is sleeved on the periphery of the pole body and contacts with the base, the sealing ring comprises a first end and a second end which are oppositely arranged along the circumferential direction, the first end and the second end are provided with gaps, and the first insulating part is abutted to one side, away from the base, of the sealing ring, and the gaps are filled with the first insulating part.

2. The end cap assembly of claim 1, wherein the end face of the first end is a first angled face disposed obliquely relative to the base, the end face of the second end is a second angled face disposed obliquely relative to the base, and the gap is located between the first angled face and the second angled face.

3. The end cap assembly of claim 1, wherein the first end is provided with a first extension and the second end is provided with a second extension;

the first extension part and the second extension part are stacked along the thickness direction of the sealing ring; or alternatively, the process may be performed,

the first extension part and the second extension part are arranged along the radial direction of the sealing ring.

4. The end cap assembly of claim 3, wherein the surface of the first extension facing the second extension is further provided with at least one recess, and the surface of the second extension facing the first extension is further provided with at least one protrusion, the protrusion being at least partially located in the recess.

5. The end cap assembly of claim 1, wherein the end cap further comprises a first stop structure looped around a sidewall surface of the end cap, the first stop structure abutting the first insulator.

6. The end cap assembly of claim 1, wherein an outer diameter dimension of the end cap is greater than an inner diameter dimension of the seal ring.

7. The end cap assembly of claim 1, wherein the inner edge of the seal ring is further provided with at least one notch, at least one of the notches being spaced from the gap in the circumferential direction of the seal ring.

8. The end cap assembly of claim 1, further comprising an end cap and a second insulator, the end cap being disposed in a stack with the second insulator, the end cap being positioned between the first insulator and the second insulator, the end cap being provided with a first through hole for the post body and the end cap to pass through, the second insulator being provided with a second through hole for the post body and the end cap to pass through, the seal ring being positioned between the second through hole and the post body, the seal ring being in an interference fit with the end cap, the second insulator being positioned between the base and the end cap, the post body passing through the second through hole and the first through hole, the end cap being in abutment with the first insulator, the first insulator being positioned in the gap between the end cap, the seal ring, and the post.

9. A battery comprising the end cap assembly of any one of claims 1-8.

10. An energy storage device comprising at least one battery according to claim 9.