Top cover assembly, battery and electric equipment

Abstract

The invention provides a top cover assembly, a battery and electric equipment. The top cover assembly comprises a top cover, lower plastic, a pole and a sealing ring. The top cover comprises a first surface and a first through hole, the first surface faces the battery cell, and the first through hole penetrates through the top cover in the thickness direction of the top cover; the lower plastic is provided with a second through hole, the second through hole penetrates through the lower plastic in the thickness direction of the lower plastic, and the second through hole is communicated with the first through hole; the pole comprises a pole base and a pole body, the pole base is connected to the surface, away from the top cover, of the lower plastic, one end of the pole body is connected with the pole base, the other end of the pole body protrudes relative to the top cover, and the pole body penetrates through the first through hole and the second through hole; the sealing ring is sleeved on the pole main body, part of the sealing ring is positioned in the second through hole and elastically propped between the top cover and the pole base, and the sealing ring positioned in the second through hole is in interference connection with the lower plastic. According to the technical scheme, the electrolyte in the battery cell can be prevented from permeating into the top cover assembly, so that the resistance of the pole is prevented from being reduced.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a top cover assembly, a battery and an electrical device. Background Art

[0002] With the development of green energy, the market demand for batteries with recyclable characteristics is also increasing. The battery includes a battery cell, a top cover assembly and a shell. The battery cell is located in the space surrounded by the top cover assembly and the shell. However, there is a certain seepage path in the top cover assembly, which causes the electrolyte to penetrate into the seepage path in the top cover assembly after the electrolyte is injected into the battery cell due to actions such as inversion and flipping of the battery. The large amount of ions in the electrolyte will play a conductive role, connecting the pole of the top cover assembly with the top cover of the top cover assembly, resulting in a decrease in the resistance of the pole. Summary of the invention

[0003] The embodiments of the present application provide a top cover assembly, a battery, and an electrical device, which can prevent the electrolyte in the battery cell from penetrating into the interior of the top cover assembly, thereby avoiding a decrease in the resistance of the electrode.

[0004] In a first aspect, the present application provides a top cover assembly, the top cover assembly comprising:

[0005] A top cover, the top cover comprising a first surface, the first surface is used to face the battery cell, the top cover is provided with a first through hole, and the first through hole penetrates the top cover along the thickness direction of the top cover;

[0006] A lower plastic, the lower plastic is connected to the first surface, the lower plastic is provided with a second through hole, the second through hole penetrates the lower plastic along the thickness direction of the lower plastic, and the second through hole is connected to the first through hole;

[0007] A pole, the pole comprising a pole base and a pole body, the pole base being connected to the surface of the lower plastic away from the top cover, one end of the pole body being connected to the pole base, the pole body passing through the first through hole and the second through hole, and the other end of the pole body being protruding relative to the top cover; and

[0008] A sealing ring is sleeved on the pole body, part of the sealing ring is located in the second through hole and elastically supported between the top cover and the pole base, and one end of the sealing ring located in the second through hole close to the lower plastic is interference connected with the lower plastic.

[0009] It is understandable that due to the thermal expansion and assembly tolerance of the battery, there will generally be a certain gap in the top cover assembly, for example, there will be a certain gap between the pole and the lower plastic, and between the sealing ring and the lower plastic. However, after the electrolyte is injected into the battery cell, the battery may be inverted and flipped during the subsequent production, assembly, transportation, etc., causing the electrolyte to penetrate into the seepage path formed by the gap in the top cover assembly, and the large number of ions in the electrolyte will play a conductive role, connecting the pole of the top cover assembly with the top cover, resulting in a decrease in the resistance of the pole.

[0010] Therefore, in the technical solution of the present application, by making the sealing ring and the lower plastic have an interference fit, the gap between the sealing ring and the lower plastic can be eliminated, so that the electrolyte that penetrates into the internal gap of the top cover assembly is blocked at the interference fit between the lower plastic and the sealing ring, avoiding the electrolyte from entering the gap between the top cover and the pole, electrically connecting the top cover and the pole, and causing the problem of decreased resistance of the pole.

[0011] For example, the outer diameter of the sealing ring may be increased or the inner diameter of the lower plastic may be reduced so that the outer diameter of the sealing ring is larger than the inner diameter of the lower plastic, thereby achieving an interference connection between the sealing ring and the lower plastic.

[0012] In a possible implementation, the sealing ring includes an outer side surface and a bottom surface, the outer side surface is the surface of one end of the sealing ring close to the lower plastic, the outer side surface is interference connected with the inner wall of the second through hole, the bottom surface is abutted against the pole base, and the outer side surface is perpendicular to the bottom surface.

[0013] In a possible implementation manner, the sealing ring includes an outer side surface, the outer side surface is a surface of the sealing ring close to one end of the lower plastic, the outer side surface is interference-connected with the inner wall of the second through hole, the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, and the first connecting surface and the second connecting surface are both inclined relative to the thickness direction of the sealing ring;

[0014] The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, and the first contact surface and the second contact surface are both inclined relative to the thickness direction of the lower plastic;

[0015] The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

[0016] In a possible implementation manner, the sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface;

[0017] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface.

[0018] In a possible implementation manner, the sealing ring further includes a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface;

[0019] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface.

[0020] In a possible implementation manner, the sealing ring includes an outer side surface, the outer side surface is a surface of the sealing ring close to one end of the lower plastic, the outer side surface is interference-connected with the inner wall of the second through hole, the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, the first connecting surface is arranged parallel to the thickness direction of the sealing ring, and the second connecting surface is arranged obliquely relative to the thickness direction of the sealing ring;

[0021] The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, the first contact surface is arranged parallel to the thickness direction of the lower plastic, and the second contact surface is arranged obliquely relative to the thickness direction of the lower plastic;

[0022] The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

[0023] In a possible implementation manner, the sealing ring further includes a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, and the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface;

[0024] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface.

[0025] In a possible implementation manner, the sealing ring further includes a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, and the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface;

[0026] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface.

[0027] In a possible implementation manner, the sealing ring includes an outer side surface, the outer side surface is a surface of the sealing ring close to one end of the lower plastic, the outer side surface is interference-connected with the inner wall of the second through hole, the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, the first connecting surface is inclined relative to the thickness direction of the sealing ring, and the second connecting surface is parallel to the thickness direction of the sealing ring;

[0028] The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, the first contact surface is inclined relative to the thickness direction of the lower plastic, and the second contact surface is parallel to the thickness direction of the lower plastic;

[0029] The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

[0030] In a possible implementation manner, the sealing ring further includes a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface;

[0031] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface.

[0032] In a possible implementation manner, the sealing ring further includes a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface;

[0033] The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface.

[0034] In a possible implementation manner, an angle formed by connecting the first connecting surface and the second connecting surface is a first angle, an angle formed by connecting the first contact surface and the second contact surface is a second angle, and the second angle is smaller than the first angle.

[0035] In a possible implementation manner, the sealing ring includes a first state and a second state;

[0036] When the sealing ring is in the first state, the sealing ring is separated from the lower plastic, and the cross-sectional width of the sealing ring along the thickness direction of the sealing ring is a first width;

[0037] When the sealing ring is in the second state, the sealing ring is in interference connection with the lower plastic, and the cross-sectional width of the sealing ring along the thickness direction of the sealing ring is a second width, which is smaller than the first width.

[0038] In a possible implementation manner, a ratio of a difference between the first width and the second width to the first width is in a range of 3% to 5%.

[0039] In a possible implementation, the sealing ring includes a sealing ring body and a connecting portion, the sealing ring body is sleeved on the pole body, spaced apart from the pole body, and interference-connected with the lower plastic, one end of the connecting portion is connected to a side of the sealing ring body away from the lower plastic, and the other end of the connecting portion abuts against the pole body.

[0040] In a possible implementation manner, the top cover is provided with a first mounting groove, the opening of the first mounting groove is located on the first surface, and the first mounting groove is coaxially arranged and communicated with the first through hole;

[0041] The lower plastic includes a lower plastic body and a first convex portion, the lower plastic body is connected to the first surface, the first convex portion is fixedly connected to the surface of the lower plastic body facing the top cover, and is located in the first mounting groove, the lower plastic is also provided with a second mounting groove, the opening of the second mounting groove is located on the surface of the lower plastic body away from the top cover, the second mounting groove is coaxially arranged and communicated with the second through hole, and part of the pole base is located in the second mounting groove.

[0042] In a second aspect, the present application further provides a battery, comprising a battery cell, a shell and a top cover assembly as described above, wherein the top cover assembly is connected to the shell and is arranged together with the shell to form a accommodating space, and the battery cell is located in the accommodating space.

[0043] In a third aspect, the present application also provides an electrical device, wherein the electrical device comprises the battery as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram of the structure of an energy storage system provided in an embodiment of the present application;

[0045] Figure 2 is a structural schematic diagram of a battery provided in an embodiment of the present application;

[0046] Figure 3 is a schematic structural diagram of a top cover assembly provided in an embodiment of the present application;

[0047] Figure 4 yes Figure 3 An exploded structural diagram of the top cover assembly shown;

[0048] Figure 5 is along Figure 3 A first cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0049] Figure 6a yes Figure 3 A schematic structural diagram of an angle of a top cover of the top cover assembly shown;

[0050] Figure 6b yes Figure 3 A schematic structural diagram of the top cover of the top cover assembly shown in FIG. 1 from another angle;

[0051] Figure 7a yes Figure 3 A schematic structural diagram of an angle of a structure of the lower plastic of the top cover assembly shown;

[0052] Figure 7b yes Figure 7a A schematic diagram of the structure of the lower plastic from another angle shown;

[0053] Figure 8 yes Figure 7a A schematic structural diagram of the lower plastic from another angle shown;

[0054] Fig. 9 is along Figure 8 A schematic cross-sectional view of a partial structure of the lower plastic obtained by cutting along the cutting line BB shown;

[0055] Fig.10a yes Figure 3 A schematic diagram of a structure of a sealing ring of a top cover assembly at an angle;

[0056] Fig.10b yes Fig.10a A schematic structural diagram of the sealing ring from another angle shown;

[0057] Fig.11a yes Figure 3 A schematic diagram of the structure of the upper plastic of the top cover assembly at an angle shown;

[0058] Fig.11b yes Figure 3 A schematic structural diagram of the upper plastic of the top cover assembly from another angle;

[0059] Fig.12 is along Fig.11a A schematic cross-sectional view of the upper plastic obtained by cutting along the cutting line CC shown;

[0060] Fig.13a yes Figure 3 A schematic structural diagram of a pole structure of a top cover assembly in a state;

[0061] Fig.13b yes Fig.13a A schematic diagram of the structure of the pole shown in another state;

[0062] Fig.14 yes Figure 3 Another schematic diagram of the structure of the pole of the top cover assembly shown;

[0063] Fig.15a is along Figure 3 A second cross-sectional schematic diagram of a portion of the structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0064] Fig.15b yes Fig.15a Enlarged view of the middle area L;

[0065] Fig.16 yes Figure 3 A schematic structural diagram of another structure of the sealing ring of the top cover assembly at an angle;

[0066] Fig.17 yes Figure 3 A schematic structural diagram of another structure of the lower plastic of the top cover assembly at an angle;

[0067] Fig.18 is along Fig.17 Another schematic cross-sectional view of a partial structure of the lower plastic obtained by cutting along the cutting line DD shown;

[0068] Fig.19a is along Figure 3 A third cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0069] Fig.19b yes Fig.19a Enlarged view of the middle area M;

[0070] Fig.20a is along Figure 3 A fourth cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0071] Fig.20b yes Fig.20a Enlarged view of the middle area N;

[0072] Fig.21a is along Figure 3 A fifth cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0073] Figure 21b yes Fig.21a Enlarged view of the middle area O;

[0074] Fig.22a is along Figure 3 A sixth cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0075] Figure 22b yes Fig.22a Enlarged view of the middle area P;

[0076] Fig.23a is along Figure 3 A seventh cross-sectional schematic diagram of a partial structure of the top cover assembly obtained by cutting along the cutting line AA shown;

[0077] Figure 23b yes Fig.23a Magnified view of the middle region Q.

[0078] Reference numerals:

[0079] Energy storage system 400, electric energy conversion device 410, first user load 420, second user load 430, electric equipment 300, battery 200, shell 210, battery cell 220, top cover assembly 100, top cover 10, lower plastic 20, sealing ring 30, upper plastic 40, pole 50, explosion-proof valve 60, explosion-proof valve protection sheet 70, first installation groove 11, first through hole 12, top cover body 13, second convex portion 14, explosion-proof hole 15, first injection hole 16, first surface 131, second surface 132, positioning groove 133, second through hole 21, second installation groove 22, lower plastic body 23, first convex portion 24, positioning portion 25, second injection hole 26, third surface 231, fourth surface 232, outer side surface 31, bottom surface 32, sealing ring body 33, connecting portion 34, inner side surface 35, top surface 36, third through hole 41, upper plastic body 42, third convex portion 43, fourth convex portion 44, third mounting groove 45, mark 46, first hole 411, second hole 412, convex structure a, concave structure b, fifth surface 421, sixth surface 422, pole body 51, pole base 52, first body 511, second body 512, third body 513, first sub-portion 513a, second sub-portion 513b, first connecting surface 311, second connecting surface 312, first transition surface 313, first contact surface 211, second contact surface 212, second transition surface 213, first angle A1, second angle A2, first width W1, second width W2. DETAILED DESCRIPTION

[0080] For ease of understanding, the terms involved in the embodiments of the present application are first explained.

[0081] And / or: It is just a way to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0082] Multiple: refers to two or more than two.

[0083] Connection: should be understood in a broad sense. For example, A and B are connected, which can be either direct or indirect through an intermediary.

[0084] The specific implementation methods of the present application will be clearly described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0085] Embodiments of the present application provide a top cover assembly, a battery, and an electrical device.

[0086] Since the energy people need is highly temporal and spatial, in order to rationally utilize energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same form or convert it into another form of energy, and then release it in a specific form of energy based on future application needs. As we all know, the current generation of green electricity generally relies on photovoltaics, wind power, water potential, etc., while wind and solar energy generally have problems of strong intermittency and volatility, which will cause instability of the power grid, insufficient electricity during peak hours, too much electricity during low hours, and unstable voltage will also cause damage to electricity. Therefore, it may cause "wind and light abandonment" problems due to insufficient electricity demand or insufficient grid acceptance capacity. To solve these problems, energy storage must be relied on. That is, electrical energy is converted into other forms of energy by physical or chemical means and stored, and energy is converted into electrical energy and released when needed. In simple terms, energy storage is similar to a large "power bank". When photovoltaic and wind energy are sufficient, electrical energy is stored and the stored electricity is released when needed.

[0087] Taking electrochemical energy storage as an example, an embodiment of the present application provides an electrical device 300, which has a group of chemical batteries inside. The chemical elements in the chemical batteries are mainly used as energy storage media. The charging and discharging process is accompanied by chemical reactions or changes in the energy storage media. Simply put, the electricity generated by wind and solar energy is stored in chemical batteries. When the use of external electricity reaches a peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0088] At present, energy storage application scenarios are quite extensive, including power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage and user side energy storage. The corresponding types of electrical equipment 300 include:

[0089] Large-scale energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the power grid, achieve load matching of electricity in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation.

[0090] The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there are large price differences in electricity charges at peak and valley locations according to electricity demand, after users have electrical equipment 300, in order to reduce costs, they usually charge the energy storage cabinet / box during the low electricity price period; during the peak electricity price period, the electricity in the electrical equipment 300 is discharged for use, so as to save electricity bills. In addition, in remote areas, as well as areas prone to natural disasters such as earthquakes and hurricanes, the presence of household electrical equipment 300 is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0091] See also Figure 1 , Figure 1 4 is a schematic diagram of the structure of the energy storage system 400 provided in the embodiment of the present application. The embodiment of the present application takes the household energy storage scenario in the user-side energy storage as an example for explanation, and the electric device 300 of the present application is not limited to the household energy storage scenario.

[0092] The embodiment of the present application provides an energy storage system 400, which includes an electric energy conversion device 410, a first user load 420, a second user load 430, and an electric device 300. The electric device 300 is a small energy storage box that can be mounted on an outdoor wall by wall-mounting. Specifically, the photovoltaic panel can convert solar energy into electric energy during the period of low electricity prices, and the electric device 300 is used to store the electric energy and supply it to street lamps and household appliances for use during the peak electricity prices, or to supply power when the power grid is out of power / power outage.

[0093] Among them, the electric device 300 may include but is not limited to single cells, battery modules, battery packs, battery systems, etc. When the electric device 300 includes multiple batteries, the multiple batteries are electrically connected and are all located inside the shell of the electric device 300, which can be protected from interference from the external environment under the protection of the shell. Exemplarily, multiple batteries are arranged at intervals. Multiple batteries can be connected in series, or in parallel, or a mixture of series and parallel connections to achieve greater capacity and power. The embodiments of the present application are described by taking the electric device 300 including a battery as an example, but it should be understood that the electric device 300 is not limited to this.

[0094] See also Figure 2 , Figure 2 It is a structural schematic diagram of a battery 200 provided in an embodiment of the present application.

[0095] For the convenience of description, the length direction of the battery 200 is defined as the X direction, the width direction of the battery 200 is defined as the Y direction, and the height direction of the battery 200 is defined as the Z direction. The X direction, the Y direction, and the Z direction are perpendicular to each other.

[0096] The battery 200 may include a top cover assembly 100, a shell 210 and a battery cell 220. The top cover assembly 100 is connected to the shell 210 and is surrounded by the shell 210 to form a receiving space, and the battery cell 220 is located in the receiving space. Exemplarily, the top cover assembly 100 may be welded to the shell 210 by welding. The shell 210 may be made of a metal material, such as an aluminum alloy. The battery 200 may be a cylindrical battery or a square battery.

[0097] It should be noted that Figure 2 The purpose is only to schematically describe the connection relationship between the top cover assembly 100, the housing 210 and the battery cell 220, and it does not specifically limit the connection position, specific structure and quantity of each device. The structure illustrated in the embodiment of the present application does not constitute a specific limitation on the battery 200. In other embodiments of the present application, the battery 200 may include Figure 2 More or fewer components may be shown, or some components may be combined or separated, or the components may be arranged differently. Figure 2 The components shown may be implemented in hardware, software or a combination of software and hardware.

[0098] With the development of green energy, the market demand for batteries with recyclable characteristics is also increasing. In the battery, the battery cell is located in the space surrounded by the top cover assembly and the shell. The top cover assembly includes structures such as poles, top covers, upper plastics, lower plastics, and sealing rings. It is understandable that the battery generates heat during the charging and discharging process, causing the plastic materials (such as sealing rings and lower plastics) in the top cover assembly to undergo thermal expansion and deformation. In order to avoid deformation or excessive pressure caused by thermal expansion, a certain gap will be left in the top cover assembly. For example, a certain gap is left between the pole and the lower plastic, and between the sealing ring and the lower plastic, so as to allow the parts in the top cover assembly to expand and contract freely. However, after injecting electrolyte into the battery cell, there will be actions such as inverting and flipping the battery in the subsequent production process, causing the electrolyte to penetrate into the seepage path formed by the gap in the top cover assembly. The large amount of ions present in the electrolyte will play a conductive role, connecting the pole of the top cover assembly with the top cover, resulting in a decrease in the resistance of the pole. For example, after the top cover assembly is soaked in the electrolyte, the resistance of the pole is reduced from more than 55GΩ before soaking to 0.001MΩ after soaking.

[0099] Therefore, the embodiment of the present application provides a top cover assembly 100, which can prevent the electrolyte in the battery cell 220 from penetrating into the top cover assembly 100, thereby preventing the resistance of the pole 50 from decreasing. The structure of the top cover assembly 100 will be described in detail below through seven specific embodiments.

[0100] First embodiment:

[0101] Please refer to Figure 3 and Figure 4 , Figure 3 is a schematic structural diagram of a top cover assembly 100 provided in an embodiment of the present application, Figure 4 yes Figure 3 A schematic diagram of the exploded structure of the top cover assembly 100 is shown.

[0102] The top cover assembly 100 may include a top cover 10, a lower plastic 20, a sealing ring 30, an upper plastic 40, a pole 50, an explosion-proof valve 60 and an explosion-proof valve protection sheet 70. The lower plastic 20 and the upper plastic 40 are respectively connected to two opposite surfaces in the thickness direction (Z direction in the figure) of the top cover 10. The pole 50 is installed on the upper plastic 40, the top cover 10, and the lower plastic 20, and can be used as an electrode lead of the battery 200. The sealing ring 30 is sleeved on the outside of the pole 50 and abuts against the surface of the top cover 10 away from the upper plastic 40. The explosion-proof valve 60 and the explosion-proof valve protection sheet 70 are both connected to the explosion-proof hole 15 on the top cover 10, and are sequentially arranged in the thickness direction of the top cover 10 to achieve pressure relief protection of the battery 200. The explosion-proof valve protection sheet 70 covers the explosion-proof valve 60.

[0103] In this embodiment, the number of poles 50 can be two, and the two poles 50 are respectively a positive pole and a negative pole. The two poles 50 are spaced apart in the length direction (X direction in the figure) of the top cover assembly 100. The number of upper plastics 40 can be two. One of the upper plastics 40 is sleeved on the positive pole. The other upper plastic 40 is sleeved on the negative pole. The number of sealing rings 30 can be two. One of the sealing rings 30 is sleeved on the positive pole. The other sealing ring 30 is sleeved on the negative pole.

[0104] The structure of the top cover assembly 100 is described below by taking the assembly of a pole 50, an upper plastic 40, a sealing ring 30, a top cover 10 and a lower plastic 20 as an example. In the absence of conflict, the following description of a pole 50, an upper plastic 40 and a sealing ring 30 can be applied to other poles 50, upper plastics 40 and sealing rings 30.

[0105] Please refer to Figure 5 , Figure 6a and Figure 6b , Figure 5 is along Figure 3 The first cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Figure 6a yes Figure 3 The schematic diagram of the structure of the top cover 10 of the top cover assembly 100 is shown at an angle. Figure 6b yes Figure 3 The schematic structural diagram of the top cover 10 of the top cover assembly 100 is shown at another angle.

[0106] The top cover 10 may extend along the X direction and be provided with a first mounting groove 11 and a first through hole 12. The opening of the first mounting groove 11 is located on the surface of the top cover 10 away from the upper plastic 40. The first mounting groove 11 may be formed by being recessed from the surface of the top cover 10 away from the upper plastic 40 toward the inside of the top cover 10. The first mounting groove 11 may be used to install the first convex portion 24 and the sealing ring 30 of the lower plastic 20. The first through hole 12 may penetrate the top cover 10 along the thickness direction of the top cover 10. The first through hole 12 is coaxially arranged and connected with the first mounting groove 11. The first through hole 12 may be located between the third through hole 41 of the upper plastic 40 and the second through hole 21 of the lower plastic 20, and is connected with the third through hole 41 of the upper plastic 40 and the second through hole 21 of the lower plastic 20. The first through hole 12 is used for the pole 50 to pass through.

[0107] There may be two first mounting grooves 11, and the two first mounting grooves 11 are spaced apart in the length direction of the top cover 10 (in the X direction shown in the figure). Each first mounting groove 11 can be used to mount a first protrusion 24 of the lower plastic 20. There may be two first through holes 12, and the two first through holes 12 can be spaced apart in the length direction of the top cover 10, and are coaxially arranged and connected with the two first mounting grooves 11, respectively. One of the first through holes 12 is used for the positive pole to pass through. The other first through hole 12 is used for the negative pole to pass through.

[0108] In this embodiment, the top cover 10 may include a top cover body 13 and a second protrusion 14. The second protrusion 14 is fixedly connected to the top cover body 13 and protrudes in the direction away from the battery cell 220. The second protrusion 14 and the top cover body 13 can be connected to form an integrated structure. Exemplarily, the second protrusion 14 and the top cover body 13 can be an integrated structure formed by connecting by methods such as one-piece molding. Alternatively, the second protrusion 14 and the top cover body 13 can also be an integrated structure formed by connecting by assembly methods such as welding and bonding. It should be noted that the integrated structures described below can all be connected by assembly methods such as one-piece molding, welding, bonding, etc., which will not be repeated.

[0109] The top cover body 13 may include a first surface 131 and a second surface 132. The first surface 131 and the second surface 132 are arranged opposite to each other in the thickness direction of the top cover 10. The first surface 131 faces the battery cell 220. The second surface 132 is away from the battery cell 220. The top cover body 13 may be provided with the first mounting groove 11 and the first through hole 12 described above. The opening of the first mounting groove 11 is located on the first surface 131. The first mounting groove 11 may be formed by being recessed from the first surface 131 to the inside of the top cover 10. The first through hole 12 may penetrate the first surface 131 and the second surface 132. That is, the first through hole 12 may penetrate the top cover body 13 along the thickness direction of the top cover body 13 (Z direction as shown in the figure).

[0110] The top cover body 13 may also be provided with a positioning groove 133. The opening of the positioning groove 133 is located on the first surface 131. The positioning groove 133 may be formed by being recessed from the first surface 131 toward the inside of the top cover 10. The positioning groove 133 and the first mounting groove 11 are spaced apart in the width direction (Y direction in the figure) of the top cover body 13. The cross-sectional width of the positioning groove 133 along the thickness direction of the top cover 10 is smaller than the cross-sectional width of the first mounting groove 11 along the thickness direction of the top cover 10. The positioning groove 133 may be used to connect with the positioning portion 25 of the lower plastic 20.

[0111] The number of the positioning grooves 133 of the top cover 10 can be one or more. When the number of the positioning grooves 133 is multiple, each positioning groove 133 is connected to a positioning portion 25 of the lower plastic 20. The multiple positioning grooves 133 can be spaced apart in the width direction of the top cover body 13. In other embodiments, the multiple positioning grooves 133 can also be spaced apart in the length direction of the top cover body 13 (X direction shown in the figure). Alternatively, the multiple positioning grooves 133 can be spaced apart along the circumferential direction of the first mounting groove 11. The circumferential direction of the first mounting groove 11 is the direction of a circle around the central axis of the first mounting groove 11. The embodiments of the present application do not impose strict restrictions on the spacing direction of the multiple positioning grooves 133, and it is only necessary to satisfy that each positioning groove 133 is connected to each positioning portion 25.

[0112] Exemplarily, the number of the positioning grooves 133 may be two. In the width direction of the top cover 10, the two positioning grooves 133 are respectively arranged on both sides of the first mounting groove 11, and are spaced apart from the first mounting groove 11. The distance between one positioning groove 133 and the first mounting groove 11 may be equal to the distance between the other positioning groove 133 and the first mounting groove 11.

[0113] The second protrusion 14 is fixedly connected to the second surface 132 of the top cover body 13. The second protrusion 14 is arranged around the outer edge of the first through hole 12, and is coaxial with the first through hole 12 and arranged at intervals. That is, the second protrusion 14 is annular and surrounds the first through hole 12. The second protrusion 14 can be installed in the third mounting groove 45 of the upper plastic 40. The cross-sectional width of the second protrusion 14 along the thickness direction of the top cover 10 gradually increases from the top cover 10 to the direction of the lower plastic 20. In other embodiments, the cross-sectional width of the second protrusion 14 along the thickness direction of the top cover assembly 100 (Z direction shown in the figure) can also remain unchanged. Or the cross-sectional width of the second protrusion 14 along the thickness direction of the top cover assembly 100 gradually decreases from the top cover 10 to the direction of the lower plastic 20. The embodiments of the present application are not strictly limited to this, as long as the second protrusion 14 can be adapted and connected with the third mounting groove 45 of the upper plastic 40. In some other embodiments, the top cover 10 may also not include the second protrusion 14.

[0114] For example, there may be two second protrusions 14, which may be spaced apart in the length direction of the top cover 10. Each second protrusion 14 surrounds the outer edge of a first through hole 12 and is coaxial with and spaced apart from a first through hole 12.

[0115] The top cover 10 may also be provided with an explosion-proof hole 15 and a first injection hole 16. In the length direction of the top cover 10, the explosion-proof hole 15 is located between the two first through holes 12 and is spaced apart from the two first through holes 12. The explosion-proof hole 15 may penetrate the first surface 131 and the second surface 132. That is, the explosion-proof hole 15 penetrates the top cover body 13 along the thickness direction of the top cover body 13. The explosion-proof hole 15 is used to connect with the explosion-proof valve 60 and the explosion-proof valve protection sheet 70. In the length direction of the top cover 10, the first injection hole 16 may be provided between the explosion-proof hole 15 and the first through hole 12 and is spaced apart from the explosion-proof hole 15 and the first through hole 12. The first injection hole 16 may penetrate the first surface 131 and the second surface 132. That is, the first injection hole 16 penetrates the top cover body 13 along the thickness direction of the top cover body 13. The first injection hole 16 is used to inject electrolyte into the battery cell 220.

[0116] Please refer to Figure 5 , Figure 7a , Figure 7b , Figure 8 and Fig. 9 , Figure 7a yes Figure 3 The schematic diagram of the structure of the lower plastic 20 of the top cover assembly 100 at an angle is shown. Figure 7b yes Figure 7a The schematic structural diagram of the lower plastic 20 from another angle is shown. Figure 8 yes Figure 7a The structural diagram of the lower plastic 20 at another angle is shown. Fig. 9 is along Figure 8 The illustrated cross-sectional diagram is a partial cross-sectional diagram of the structure of the lower plastic 20 cut along the cutting line BB.

[0117] The lower plastic 20 is connected to the first surface 131 of the top cover 10. A portion of the lower plastic 20 is located inside the top cover 10. The lower plastic 20 can be used to accommodate the pole base 52 of the pole 50. That is, a portion of the lower plastic 20 is located between the top cover 10 and the pole base 52 of the pole 50. The portion of the surface of the lower plastic 20 that is away from the top cover 10 abuts against the surface of the pole base 52 close to the pole body 51.

[0118] The lower plastic 20 may be provided with a second through hole 21. The second through hole 21 may penetrate the lower plastic 20 along the thickness direction of the lower plastic 20 (Z direction in the figure). The second through hole 21 is coaxially arranged and connected with the first through hole 12 of the top cover 10. The inner wall of the second through hole 21 is arranged perpendicularly to the surface of the lower plastic 20 away from the top cover 10 (allowing tolerance range). The inner wall of the second through hole 21 is a surface surrounding the central axis of the second through hole 21. The second through hole 21 can be used for the pole 50 to pass through and accommodate the third body 513 of the pole 50. The inner wall of the second through hole 21 can be spaced from the outer peripheral surface of the third body 513 of the pole 50. Among them, the outer peripheral surface of the third body 513 of the pole 50 is an outer surface surrounding the central axis of the third body 513. The gap area between the inner wall of the second through hole 21 and the outer peripheral surface of the third body 513 of the pole 50 can be used to accommodate part of the sealing ring 30. The inner wall of the second through hole 21 can be interference-connected with the outer side surface 31 of the sealing ring 30. The outer side surface 31 of the sealing ring 30 is an outer surface surrounding the central axis of the sealing ring 30. That is, the outer side surface 31 of the sealing ring 30 is a surface of the sealing ring 30 close to one end of the lower plastic 20.

[0119] For example, the number of the second through holes 21 may be two. The two second through holes 21 may be spaced apart in the length direction (X direction in the figure) of the lower plastic 20. One of the second through holes 21 is used to install the positive pole. The other second through hole 21 is used to install the negative pole.

[0120] In a possible implementation, Figure 7b As shown, the lower plastic 20 may be provided with a second mounting groove 22. The opening of the second mounting groove 22 is located on the surface of the lower plastic 20 away from the top cover 10, and is formed by being recessed from the surface of the lower plastic 20 away from the top cover 10 to the inside of the lower plastic 20. The second mounting groove 22 is coaxially arranged and connected with the second through hole 21. The cross-sectional width of the second mounting groove 22 along the thickness direction of the lower plastic 20 is greater than the cross-sectional width of the second through hole 21 along the thickness direction of the lower plastic 20. The second mounting groove 22 can be used to accommodate part of the pole base 52 of the pole 50. The bottom wall of the second mounting groove 22 abuts against the surface of the pole base 52 of the pole 50 close to the pole body 51. Among them, the bottom wall of the second mounting groove 22 and the opening of the second mounting groove 22 are arranged oppositely in the thickness direction of the lower plastic 20. The inner peripheral wall of the second mounting groove 22 abuts against part of the outer peripheral surface of the pole base 52. Part of the pole base 52 protrudes from the second mounting groove 22. The inner peripheral wall of the second installation groove 22 is a surface surrounding the central axis of the second installation groove 22. The outer peripheral surface of the pole base 52 is an outer surface surrounding the central axis of the pole base 52.

[0121] For example, there may be two second mounting grooves 22, which are spaced apart in the length direction of the lower plastic 20. Each second mounting groove 22 is coaxially arranged and communicated with a second through hole 21, and can be used to accommodate a pole base 52 of a pole 50.

[0122] It can be understood that by providing the first protrusion 24 and the second mounting groove 22 on the lower plastic 20, and making the inner wall of the second mounting groove 22 abut against the outer surface of the pole base 52 of the pole 50, the contact area between the lower plastic 20 and the pole 50 can be effectively increased, so as to further increase the length of the path for the electrolyte of the battery cell 220 to penetrate into the interior of the top cover assembly 100, thereby reducing the penetration of the electrolyte into the interior of the top cover assembly 100 to a certain extent, and preventing the electrolyte from penetrating into the interior of the top cover assembly 100, electrically connecting the pole 50 with the top cover 10, resulting in a problem of a decrease in the resistance of the pole 50.

[0123] In this embodiment, the lower plastic 20 may include a lower plastic body 23 and a first protrusion 24. The first protrusion 24 is fixedly connected to the lower plastic body 23 and protrudes in a direction away from the battery cell 220. The first protrusion 24 and the lower plastic body 23 may be connected to form an integrated structure.

[0124] The lower plastic body 23 may include a third surface 231 and a fourth surface 232. The third surface 231 and the fourth surface 232 are arranged opposite to each other in the thickness direction of the lower plastic body 23 (Z direction in the figure), and are respectively connected to the two ends of the inner wall of the second through hole 21. The third surface 231 faces the battery cell 220. The fourth surface 232 is away from the battery cell 220. The fourth surface 232 is connected to the first surface 131 of the top cover 10. The lower plastic body 23 may be an integrated structure. Alternatively, the lower plastic body 23 may be a split structure. Specifically, the lower plastic body 23 may include a first part and a second part. The first part and the second part are arranged in sequence in the length direction of the lower plastic body 23 (X direction in the figure). The first part is detachably connected to the second part. The separable part of the first part and the second part is as shown in FIG. Figure 7a , Figure 7b and Figure 8 Indicated by the dotted arrow.

[0125] The first protrusion 24 is fixedly connected to the fourth surface 232 of the top cover body 13 and is protruded relative to the fourth surface 232. The first protrusion 24 is located in the first mounting groove 11 of the top cover 10. The surface of the first protrusion 24 facing away from the top cover body 13 abuts against the bottom wall of the first mounting groove 11. Through the connection between the first protrusion 24 of the lower plastic 20 and the first mounting groove 11 of the top cover 10, the alignment connection between the lower plastic 20 and the top cover 10 can be helped, thereby improving the assembly efficiency of the top cover assembly 100 and the battery 200.

[0126] Exemplarily, the number of the first protrusions 24 may be two, and the two first protrusions 24 may be spaced apart in the length direction of the lower plastic 20. Each first protrusion 24 is located in the first mounting groove 11 of a top cover 10. The lower plastic body 23 and the first protrusion 24 may be provided with the second through hole 21 and the second mounting groove 22 described above. Among them, the opening of the second mounting groove 22 may be located on the third surface 231. The second mounting groove 22 may be formed by being recessed from the third surface 231 to the inside of the lower plastic 20. The bottom wall of the second mounting groove 22 may be located in the lower plastic body 23, and the second through hole 21 may penetrate the first protrusion 24 and at least part of the lower plastic body 23 along the thickness direction of the lower plastic 20. Alternatively, the bottom wall of the second mounting groove 22 may be located in the first protrusion 24, and the second through hole 21 may penetrate part of the first protrusion 24 along the thickness direction of the lower plastic 20. Alternatively, the bottom wall of the second mounting groove 22 may be flush with the fourth surface 232 , and the second through hole 21 may penetrate the first protrusion 24 along the thickness direction of the lower plastic 20 .

[0127] In this embodiment, the lower plastic 20 may be provided with a positioning portion 25. The positioning portion 25 is connected to the fourth surface 232 of the lower plastic body 23, and is spaced apart from the first protrusion 24 in the width direction (Y direction in the figure) of the lower plastic 20. The cross-sectional width of the positioning portion 25 along the thickness direction of the lower plastic 20 is smaller than the cross-sectional width of the first protrusion 24 along the thickness direction of the lower plastic 20. The positioning portion 25 may be used to connect with the positioning groove 133 of the top cover 10.

[0128] The number of the positioning portions 25 may be one or more. When the number of the positioning portions 25 is multiple, the multiple positioning portions 25 may be spaced apart in the width direction of the lower plastic 20. Of course, in other embodiments, the multiple positioning portions 25 may also be spaced apart in the length direction of the lower plastic 20. Alternatively, the multiple positioning portions 25 may be spaced apart along the circumferential direction of the first protrusion 24. The circumferential direction of the first protrusion 24 is a direction that surrounds the central axis of the first protrusion 24. The embodiments of the present application do not impose strict restrictions on the spacing direction of the multiple positioning portions 25, and it is only necessary that each positioning portion 25 is connected to a positioning groove 133 of a top cover 10.

[0129] For example, when there are two positioning portions 25, the two positioning portions 25 are spaced apart from the first protrusion 24 in the width direction of the lower plastic 20. The distance between one positioning portion 25 and the first protrusion 24 is equal to the distance between the other positioning portion 25 and the first protrusion 24. Each positioning portion 25 is plugged into a positioning groove 133 of the top cover 10.

[0130] It is understandable that by providing the positioning portion 25 on the lower plastic 20 and connecting the positioning portion 25 with the positioning groove 133 on the top cover 10, the lower plastic 20 and the top cover 10 can be assembled more quickly and the overall production efficiency of the top cover assembly 100 can be improved. At the same time, the connection between the positioning portion 25 and the positioning groove 133 can also enhance the connection stability between the lower plastic 20 and the top cover 10.

[0131] In other embodiments, a groove may be provided on the lower plastic 20 and a protrusion may be provided on the top cover 10. The connection between the protrusion and the groove may also improve the connection efficiency and connection stability between the top cover 10 and the lower plastic 20.

[0132] In this embodiment, the lower plastic 20 may be provided with a second injection hole 26. The second injection hole 26 may be disposed between the two second through holes 21 and spaced apart from the two second through holes 21. The second injection hole 26 may penetrate the third surface 231 and the fourth surface 232. That is, the second injection hole 26 may penetrate the lower plastic body 23 along the thickness direction of the lower plastic body 23. The second injection hole 26 is coaxially disposed and communicated with the first injection hole 16 of the top cover 10, and is used to inject electrolyte into the battery cell 220.

[0133] Please refer to Figure 5 , Fig.10a and Fig.10b , Fig.10a yes Figure 3 The schematic diagram of the structure of the sealing ring 30 of the top cover assembly 100 is shown in FIG. Fig.10b yes Fig.10a A schematic structural diagram of the sealing ring 30 is shown at another angle.

[0134] The sealing ring 30 can be sleeved on the pole body 51 of the pole 50, and elastically abutted between the top cover 10 and the pole base 52 of the pole 50. The sealing ring 30 can also be located between the fourth protrusion 44 of the upper plastic 40 and the pole base 52 of the pole 50. Specifically, the sealing ring 30 is elastic, and the surface of the sealing ring 30 facing away from the battery cell 220 can abut and be squeezed against the bottom of the first mounting groove 11 of the top cover 10, and is spaced from the fourth protrusion 44 of the upper plastic 40. The surface of the sealing ring 30 close to the battery cell 220 can abut and be squeezed against the surface of the pole base 52 of the pole 50 close to the pole body 51. Figure 5 The portion where the middle sealing ring 30 and the top cover 10 overlap is the first compression zone of the sealing ring 30 .

[0135] Part of the sealing ring 30 is located in the second through hole 21 of the lower plastic 20 and is interference connected with the lower plastic 20. Specifically, the sealing ring 30 may include an outer side surface 31, a bottom surface 32 and a top surface 36. The top surface 36 and the bottom surface 32 are arranged opposite to each other in the thickness direction of the sealing ring 30 (Z direction in the figure), and are respectively connected to the two ends of the outer side surface 31 of the sealing ring 30. The top surface 36 abuts against the bottom wall of the first mounting groove 11 of the top cover 10. The bottom surface 32 abuts against the surface of the pole base 52 of the pole 50 close to the pole body 51. The outer side surface 31 is interference connected with the inner wall of the second through hole 21 of the lower plastic 20. The outer side surface 31 and the bottom surface 32 are arranged vertically (allowing tolerance range). Figure 5 The overlapping portion of the middle sealing ring 30 and the lower plastic 20 is the second compression zone of the sealing ring 30 .

[0136] It can be understood that, since the outer side surface 31 of the sealing ring 30 is perpendicular to the bottom surface 32, in order to facilitate the assembly of the sealing ring 30 and the lower plastic 20, the inner wall of the second through hole 21 of the lower plastic 20 abutting against the outer side surface 31 of the sealing ring 30 can also be adjusted accordingly to be perpendicular to the surface of the lower plastic 20 away from the top cover 10. This makes it easier for the right-angled surface of the sealing ring 30 to be installed in the second through hole 21 of the lower plastic 20 when the lower plastic 20 and the sealing ring 30 are assembled, which is beneficial to improve the assembly efficiency of the sealing ring 30 and the lower plastic 20.

[0137] Furthermore, since the sealing ring 30 is in close contact with the lower plastic 20, the electrolyte can be further prevented from penetrating into the interior of the top cover assembly 100, and the problem of the electrolyte penetrating into the gap between the top cover 10 and the pole 50, causing the top cover 10 and the pole 50 to be electrically connected, resulting in a decrease in the resistance of the pole 50, can be avoided.

[0138] In this embodiment, the sealing ring 30 can include a first state and a second state. The first state of the sealing ring 30 is a separation state where the sealing ring 30 is not assembled with the lower plastic 20 , and the second state of the sealing ring 30 is an assembly state where the sealing ring 30 is assembled with the lower plastic 20 .

[0139] Specifically, when the sealing ring 30 is in the first state, the sealing ring 30 is separated from the lower plastic 20, and the cross-sectional width of the sealing ring 30 along the thickness direction of the sealing ring 30 is the first width W1. When the sealing ring 30 is in the second state, the sealing ring 30 and the lower plastic 20 are interference-connected, and the cross-sectional width of the sealing ring 30 along the thickness direction of the sealing ring 30 is the second width W2. The second width W2 can be smaller than the first width W1.

[0140] It is understandable that, when the sealing ring 30 switches from the first state to the second state, the cross-sectional width of the sealing ring 30 along the thickness direction of the sealing ring 30 will become smaller. Therefore, when the sealing ring 30 is assembled with the upper plastic 40, it will be squeezed laterally by the squeezing force of the upper plastic 40 along the thickness direction perpendicular to the sealing ring 30. That is, the direction in which the sealing ring 30 is squeezed by the lower plastic 20 is perpendicular to the bottom surface 32 of the sealing ring 30, which enables the lower plastic 20 to be in close contact with the outer periphery of the sealing ring 30, which can not only improve the connection strength between the sealing ring 30 and the lower plastic 20, but also further ensure that it is not easy to have a gap between the sealing ring 30 and the lower plastic 20 to cause electrolyte penetration, and the reliability is better.

[0141] The difference between the first width W1 and the second width W2 accounts for a ratio of 3% to 5% of the first width W1 (including the end values ​​of 3% and 5%). That is, the volume of the sealing ring 30 squeezed by the lower plastic 20 ( Figure 5 The ratio of the volume of the second compression area of ​​the sealing ring 30, or the volume of the first compression area and the second compression area, to the total volume of the sealing ring 30 is in the range of 3% to 5% (including the endpoints 3% and 5%). That is, the compression amount of the sealing ring 30 can be in the range of 3% to 5% (including the endpoints 3% and 5%).

[0142] It is understandable that, after verification, when the compression amount of the sealing ring 30 is within the range of 3% to 5%, the electrolyte can be effectively blocked from penetrating into the gap between the pole 50 and the top cover 10. Even if the battery 200 is turned upside down or flipped during production, assembly, and transportation, the resistance of the pole 50 will not decrease, and the value before the electrolyte penetration can still be maintained, and the stability is relatively strong.

[0143] The sealing ring 30 is sleeved on the pole body 51 of the pole 50. Specifically, the sealing ring 30 may include a sealing ring body 33 and a connecting portion 34. The sealing ring body 33 is sleeved on the third body 513 of the pole 50. The inner side surface 35 of the sealing ring body 33 is spaced from the outer peripheral surface of the third body 513 of the pole 50. Among them, the inner side surface 35 of the sealing ring body 33 is the surface of the sealing ring body 33 away from the inner wall of the second through hole 21 of the lower plastic 20. The circumferential direction of the inner side surface 35 of the sealing ring body 33 may be a direction around the central axis of the inner side surface 35. The outer side surface 31 of the sealing ring body 33 is interference connected with the inner wall of the second through hole 21 of the lower plastic 20. One end of the connecting portion 34 is connected to the inner side surface 35 of the sealing ring body 33. The other end of the connecting portion 34 abuts against the third body 513 of the pole 50. That is, the connecting portion 34 is located between the sealing ring body 33 and the third body 513 of the pole 50. The connecting portion 34 and the sealing ring 30 may be an integrated structure. In this embodiment, the shape of the connecting portion 34 is not limited.

[0144] The number of the sealing rings 30 may be two. The two sealing rings 30 may be arranged at intervals in the length direction of the top cover assembly 100. One of the sealing rings 30 is sleeved on the positive pole. The other sealing ring 30 is sleeved on the negative pole. The number of the connecting parts 34 may be one or more. One end of each connecting part 34 is connected to the inner side surface 35 of the sealing ring body 33, and the other end is abutted against the pole body 51 of the pole 50. When the number of the connecting parts 34 is multiple, the multiple connecting parts 34 may be arranged at intervals along the circumferential direction of the inner side surface 35 of the sealing ring body 33. Providing the connecting parts 34 on the sealing ring 30 can enhance the connection stability between the sealing ring 30 and the pole 50. Moreover, even if multiple connecting parts 34 are provided on the sealing ring 30, these connecting parts 34 are also arranged at intervals. This can not only save space between the sealing ring 30 and the pole 50, but also save costs.

[0145] It is understandable that, due to thermal expansion and assembly tolerance of the battery 200, there is generally a certain gap in the top cover assembly 100, for example, there is a certain gap between the pole 50 and the lower plastic 20, and between the sealing ring 30 and the lower plastic 20. However, after the electrolyte is injected into the battery cell 220, the battery 200 may be inverted and flipped in the subsequent production process, causing the electrolyte to penetrate into the seepage path formed by the gap in the top cover assembly 100, and the large number of ions in the electrolyte will play a conductive role, electrically connecting the pole 50 of the top cover assembly 100 with the top cover 10, resulting in a decrease in the resistance of the pole 50.

[0146] Therefore, in this embodiment, by making the sealing ring 30 and the lower plastic 20 have an interference fit, the gap between the sealing ring 30 and the lower plastic 20 can be eliminated, so that the electrolyte that penetrates into the internal gap of the top cover assembly 100 is blocked at the interference fit between the lower plastic 20 and the sealing ring 30, thereby preventing the electrolyte from entering the gap between the top cover 10 and the pole 50, electrically connecting the top cover 10 and the pole 50, and causing the problem of reduced resistance of the pole 50.

[0147] For example, the outer diameter of the sealing ring 30 may be increased or the inner diameter of the lower plastic 20 may be reduced so that the outer diameter of the sealing ring 30 is larger than the inner diameter of the lower plastic 20 , thereby achieving interference connection between the sealing ring 30 and the lower plastic 20 .

[0148] Please refer to Figure 5 , Fig.11a , Fig.11b and Fig.12 , Fig.11a yes Figure 3 The schematic diagram of the structure of the upper plastic 40 of the top cover assembly 100 at an angle is shown. Fig.11b yes Figure 3 The schematic structural diagram of the upper plastic 40 of the top cover assembly 100 from another angle is shown. Fig.12 is along Fig.11a The illustrated diagram is a cross-sectional view of the upper plastic 40 obtained by cutting along the cutting line CC.

[0149] The upper plastic 40 is mounted on the top cover 10 and is sleeved on the outer side of the pole body 51 of the pole 50. Part of the upper plastic 40 is located in the first through hole 12 of the top cover 10. Part of the upper plastic 40 is protruded relative to the surface of the top cover 10 away from the lower plastic 20. The upper plastic 40 may be provided with a third through hole 41. The third through hole 41 may penetrate the upper plastic 40 along the thickness direction of the upper plastic 40 (Z direction in the figure). The third through hole 41 of the upper plastic 40 may be coaxially arranged and connected with the first through hole 12 of the top cover 10 and the second through hole 21 of the lower plastic 20. The third through hole 41 is used for the pole 50 to pass through and for accommodating the second body 512 and the third body 513 of the pole 50. The inner wall of the third through hole 41 may abut against the outer peripheral surface of the second body 512 and the outer peripheral surface of the third body 513 of the pole 50. Among them, the inner wall of the third through hole 41 is a surface surrounding the central axis of the third through hole 41. The outer peripheral surface of the second body 512 is an outer surface surrounding the central axis of the second body 512 .

[0150] The third through hole 41 may include a first hole 411 and a second hole 412. The first hole 411 is coaxially arranged with the second hole 412 and is in communication with each other. The opening of the first hole 411 at one end away from the second hole 412 is located on the surface of the upper plastic 40 away from the top cover 10. The opening of the second hole 412 at one end away from the first hole 411 is located on the surface of the upper plastic 40 close to the top cover 10. The cross-sectional width of the first hole 411 along the thickness direction of the upper plastic 40 is greater than the cross-sectional width of the second hole 412 along the thickness direction of the upper plastic 40. The first hole 411 of the upper plastic 40 is used to accommodate the second body 512 of the pole 50. The second hole 412 of the upper plastic 40 is used to accommodate the third body 513 of the pole 50.

[0151] The inner wall of the third through hole 41 is provided with a protruding structure a. The protruding structure a is used to connect with the recessed structure b on the outer peripheral surface of the pole body 51. The shape of the protruding structure a can be adapted to the shape of the recessed structure b on the outer peripheral surface of the pole body 51. Among them, the outer peripheral surface of the pole body 51 is the outer surface surrounding the central axis of the pole body 51. Exemplarily, the protruding structure a can be a mesh structure, a "cross" structure, a diamond structure, etc. The protruding structure a can be connected to the recessed structure b on the pole 50 by a connection method such as a snap-on connection. Providing the protruding structure a and the recessed structure b on the upper plastic 40 and the pole 50 respectively can increase the connection stability between the upper plastic 40 and the pole 50.

[0152] In this embodiment, the protrusion structure a can be set on part of the inner wall of the third through hole 41, or on the entire inner wall of the third through hole 41, as long as the inner wall of the third through hole 41 can be adaptably connected to the pole body 51 at the corresponding position.

[0153] Exemplarily, the number of the third through holes 41 may be two, and the two third through holes 41 may be spaced apart in the length direction (X direction in the figure) of the upper plastic 40. One of the third through holes 41 is used for the positive pole to pass through. The other third through hole 41 is used for the negative pole to pass through. Moreover, for the same third through hole 41, a protruding structure a may be provided on the inner wall of the first hole 411 of the third through hole 41. Alternatively, a protruding structure a may be provided on the inner wall of the second hole 412 of the third through hole 41. Alternatively, a protruding structure a may be provided on both the inner wall of the first hole 411 of the third through hole 41 and the inner wall of the second hole 412.

[0154] In this embodiment, the upper plastic 40 may include an upper plastic body 42, a third protrusion 43 and a fourth protrusion 44. The third through hole 41 mentioned above is provided on the upper plastic body 42, the third protrusion 43 and the fourth protrusion 44, and extends along the thickness of the upper plastic 40.

[0155] The upper plastic body 42 may include a fifth surface 421 and a sixth surface 422. The fifth surface 421 and the sixth surface 422 are disposed opposite to each other in the thickness direction of the upper plastic 40. The fifth surface 421 faces the battery cell 220. The sixth surface 422 faces away from the battery cell 220. The fifth surface 421 is connected to the second surface 132 of the top cover 10.

[0156] The third protrusion 43 and the fourth protrusion 44 are coaxially arranged and arranged opposite to each other in the thickness direction of the upper plastic 40. The third protrusion 43 is connected to the sixth surface 422. The fourth protrusion 44 is connected to the fifth surface 421. The fourth protrusion 44 is located in the first through hole 12 of the top cover 10. The fourth protrusion 44 can play an insulating role and is used to separate the top cover 10 from the pole 50 to prevent the top cover 10 and the pole 50 from directly contacting each other and causing a short circuit.

[0157] Exemplarily, the third protrusion 43 and the upper plastic body 42 may cooperate to form the first hole 411 of the third through hole 41 described above. The first hole 411 may penetrate the third protrusion 43 and a portion of the upper plastic body 42 along the thickness direction of the upper plastic 40. The fourth protrusion 44 and the upper plastic body 42 may cooperate to form the second hole 412 of the first through hole 12 described above. The second hole 412 may penetrate the third protrusion 43 and a portion of the upper plastic body 42 along the thickness direction of the upper plastic 40. The upper plastic body 42, the third protrusion 43 and the fourth protrusion 44 may be an integrated structure formed by connecting in a manner such as integral molding.

[0158] In this embodiment, the upper plastic 40 is further provided with a third mounting groove 45. The opening of the third mounting groove 45 is located on the fifth surface 421. The third mounting groove 45 can be formed by being recessed from the fifth surface 421 to the inner part of the upper plastic body 42. The third mounting groove 45 is arranged around the outer edge of the fourth protrusion 44, and is coaxial with the fourth protrusion 44 and arranged at intervals. That is, the third mounting groove 45 is annular and surrounds the fourth protrusion 44. The third mounting groove 45 can be used to install the second protrusion 14 of the top cover 10. The cross-sectional width of the third mounting groove 45 along the thickness direction of the upper plastic 40 gradually increases from the upper plastic 40 to the top cover 10. In other embodiments, the cross-sectional width of the third mounting groove 45 along the thickness direction of the upper plastic 40 can remain unchanged, and there is no strict restriction on this, as long as the third mounting groove 45 can be adapted and connected with the second protrusion 14 of the top cover 10.

[0159] For example, the number of the third mounting grooves 45 can be two, and the two third mounting grooves 45 can be spaced apart in the length direction of the top cover assembly 100. Each third mounting groove 45 is disposed around the outer edge of the fourth protrusion 44, and is coaxial with the fourth protrusion 44 and spaced apart.

[0160] The upper plastic 40 may also be provided with a mark 46. The mark 46 is adjacent to the third through hole 41 and is arranged at intervals. The mark 46 may be located on the third protrusion 43. In other embodiments, the mark 46 may also be located on the upper plastic body 42. The mark 46 is used to mark the positive polarity or negative polarity of the pole 50 installed in the third through hole 41 of the upper plastic 40, so as to more efficiently align the third through hole 41 with the pole of positive polarity or the pole of negative polarity, and help the pole 50 of corresponding polarity to be installed in the corresponding third through hole 41.

[0161] Exemplarily, the number of the marks 46 may be two. The two marks 46 are respectively adjacent to the two third through holes 41 and are arranged at intervals. A "+"-shaped mark 46 is provided around the third through hole 41 connected to the positive pole. A "-"-shaped mark 46 is provided around the third through hole 41 connected to the negative pole. Alternatively, the number of the marks 46 may be four. Two "+"-shaped marks 46 are provided around the third through hole 41 connected to the positive pole. The two "+"-shaped marks 46 are adjacent to and spaced apart from the corresponding third through holes 41 in the width direction of the upper plastic 40 (the Y direction shown in the figure). Two "-"-shaped marks 46 are provided around the third through hole 41 connected to the negative pole. The two "-"-shaped marks 46 are adjacent to and spaced apart from the corresponding third through holes 41 in the width direction of the upper plastic 40.

[0162] Please refer to Figure 5 , Fig.13a and Fig.13b , Fig.13a yes Figure 3 A schematic diagram of a structure of a pole 50 of a top cover assembly 100 in a state is shown, Fig.13b yes Fig.13a The schematic diagram of the structure of the pole 50 in another state is shown in FIG. Fig.14 yes Figure 3 Another schematic structural diagram of the pole 50 of the top cover assembly 100 is shown.

[0163] The pole 50 is mounted on the upper plastic 40, the top cover 10 and the lower plastic 20. The opposite ends of the pole 50 are respectively protruded relative to the sixth surface 422 of the upper plastic 40 and the third surface 231 of the lower plastic 20. Specifically, the pole 50 may include a pole body 51 and a pole base 52. The pole base 52 is located on the side of the top cover 10 away from the upper plastic 40. One end of the pole body 51 is fixedly connected to the pole base 52. The pole body 51 passes through the second through hole 21 of the lower plastic 20, the first through hole 12 of the top cover 10 and the third through hole 41 of the upper plastic 40, and the other end of the pole body 51 extends out of the upper plastic 40.

[0164] The pole body 51 may include a first body 511, a second body 512 and a third body 513. The first body 511, the second body 512 and the third body 513 are connected in sequence and coaxially arranged. The third body 513 is connected to the pole base 52, and the second body 512 is connected between the third body 513 and the first body 511. The cross-sectional width of the second body 512 along the thickness direction of the pole 50 (Z direction in the figure) is greater than the cross-sectional width of the first body 511 along the thickness direction of the pole 50, and is also greater than the cross-sectional width of the third body 513 along the thickness direction of the pole 50. The cross-sectional width of the pole base 52 along the thickness direction of the pole 50 is greater than the cross-sectional width of the pole body 51 (including the first body 511, the second body 512 and the third body 513) along the thickness direction of the pole 50.

[0165] It is understandable that by configuring the pole body 51 to be three parts of different sizes, the upper plastic 40, the top cover 10, the lower plastic 20 and the sealing ring 30 can be better installed in the corresponding parts to avoid installation misalignment. Moreover, the size of the pole base 52 is larger than the size of the pole body 51, which can effectively prevent the pole 50 from slipping.

[0166] In a possible implementation, please refer to Figure 5 , Fig.13a and Fig.13b, the third body 513 includes a first sub-section 513a and a second sub-section 513b. One end of the first sub-section 513a is connected to the second body 512. The other end of the first sub-section 513a is connected to the second sub-section 513b, and the end of the second sub-section 513b away from the first sub-section 513a is connected to the pole base 52. The cross-sectional width of the first sub-section 513a along the thickness direction of the pole 50 is equal to the cross-sectional width of the second sub-section 513b along the thickness direction of the pole 50. The first sub-section 513a can be connected to the first body 511 and the second body 512 to form an integrated structure. The second sub-section 513b can be connected to the pole base 52 to form an integrated structure. The first sub-section 513a and the second sub-section 513b are detachably connected.

[0167] In this embodiment, the first body 511 of the pole 50 is protruded relative to the sixth surface 422 of the upper plastic 40. The second body 512 of the pole 50 is located in the third through hole 41 of the upper plastic 40. The third body 513 of the pole 50 is located in the third through hole 41 of the upper plastic 40, the first through hole 12 of the top cover 10 and the second through hole 21 of the lower plastic 20. Part of the pole base 52 is located in the second mounting groove 22 of the lower plastic 20, and part of it is protruded relative to the third surface 231 of the lower plastic body 23.

[0168] That is, the upper plastic 40 is sleeved on the second body 512 and the first sub-section 513a of the third body 513 of the pole 50. The inner wall of the first hole 411 of the third through hole 41 of the upper plastic 40 abuts against the outer peripheral surface of the second body 512 of the pole 50. The inner wall of the second hole 412 of the third through hole 41 of the upper plastic 40 abuts against the outer peripheral surface of the first sub-section 513a of the third body 513. Among them, the outer peripheral surface of the first sub-section 513a is an outer surface that surrounds the central axis of the first sub-section 513a. The top cover 10 is sleeved on the first sub-section 513a and the second sub-section 513b of the third body 513 of the pole 50, and is separated from the pole 50 by the fourth protrusion 44 of the upper plastic 40. Part of the inner wall of the first through hole 12 of the top cover 10 abuts against the outer peripheral surface of the fourth protrusion 44 of the upper plastic 40. The outer peripheral surface of the fourth protrusion 44 is an outer surface that surrounds the central axis of the fourth protrusion 44.

[0169] The sealing ring 30 is sleeved on the first sub-section 513a and the second sub-section 513b of the third body 513 of the pole 50. The end of the connecting portion 34 of the sealing ring 30 away from the sealing ring body 33 abuts against a part of the outer peripheral surface of the second sub-section 513b of the third body 513 and a part of the outer peripheral surface of the first sub-section 513a. Among them, the outer peripheral surface of the second sub-section 513b is an outer surface that surrounds the central axis of the second sub-section 513b. The surface of the sealing ring 30 facing away from the upper plastic 40 abuts against the surface of the pole base 52 close to the pole body 51. The lower plastic 20 is sleeved on the first sub-section 513a and the second sub-section 513b of the third body 513 and the pole base 52. The second through hole 21 of the lower plastic 20 is separated from the third body 513 of the pole 50 by the sealing ring 30. The inner wall of the second through hole 21 of the lower plastic 20 abuts against the outer side surface 31 of the sealing ring 30. The inner peripheral wall of the second installation groove of the lower plastic 20 abuts against a portion of the outer peripheral surface of the pole base 52. A portion of the pole base 52 protrudes from the third surface 231 of the lower plastic 20.

[0170] For another possible implementation, see Fig.14 The same contents as the previous embodiment are not repeated here. The difference from the previous embodiment is that the first sub-section 513a and the second sub-section 513b are connected to form an integrated structure. That is, the pole base 52 and the first body 511, the second body 512, and the third body 513 of the pole body 51 can be an integrated structure.

[0171] In this embodiment, the first body 511 of the pole 50 is protruded relative to the sixth surface 422 of the upper plastic 40. The second body 512 of the pole 50 is located in the third through hole 41 of the upper plastic 40. The third body 513 of the pole 50 is located in the third through hole 41 of the upper plastic 40, the first through hole 12 of the top cover 10 and the second through hole 21 of the lower plastic 20. Part of the pole base 52 is located in the second mounting groove 22 of the lower plastic 20, and part of it is protruded relative to the third surface 231 of the lower plastic body 23.

[0172] That is, the upper plastic 40 is sleeved on the second body 512 and part of the third body 513 of the pole 50. The inner wall of the first hole 411 of the third through hole 41 of the upper plastic 40 abuts against the outer peripheral surface of the second body 512 of the pole 50. The inner wall of the second hole 412 of the third through hole 41 of the upper plastic 40 abuts against part of the outer peripheral surface of the third body 513 of the pole 50. The top cover 10 is sleeved on the third body 513 of the pole 50 and is separated from the pole 50 by the fourth protrusion 44 of the upper plastic 40. Part of the inner wall of the first through hole 12 of the top cover 10 abuts against the outer peripheral surface of the fourth protrusion 44 of the upper plastic 40. The sealing ring 30 is sleeved on the third body 513 of the pole 50. One end of the connecting portion 34 of the sealing ring 30 away from the inner side surface 35 of the sealing ring body 33 abuts against part of the outer peripheral surface of the third body 513 of the pole 50. The surface of the sealing ring 30 facing away from the upper plastic 40 abuts against the surface of the pole base 52 close to the pole body 51. The lower plastic 20 is sleeved on a portion of the third body 513 of the pole 50 and a portion of the pole base 52. The second through hole 21 of the lower plastic 20 is separated from the portion of the third body 513 of the pole 50 by the sealing ring 30. The inner wall of the second through hole 21 of the lower plastic 20 abuts against the outer side surface 31 of the sealing ring 30. The inner peripheral wall of the second mounting groove 22 of the lower plastic 20 abuts against a portion of the outer peripheral surface of the pole base 52. Part of the pole base 52 protrudes from the third surface 231 of the lower plastic 20.

[0173] In this embodiment, a recessed structure b is provided on the outer circumference of the pole body 51. The recessed structure b is used to connect with the protruding structure a on the inner wall of the third through hole 41 of the upper plastic 40. In other embodiments, the protruding structure a may be provided on the outer circumference of the pole body 51, and the recessed structure b may be provided on the inner wall of the third through hole 41 of the upper plastic 40, and this is not strictly limited.

[0174] Among them, the recessed structure b can be provided on part of the outer circumference of the pole body 51, or the recessed structure b can be provided on the entire outer circumference of the pole body 51. As long as the outer circumference of the pole body 51 and the inner wall of the third through hole 41 at the corresponding position can be matched and connected. It should be noted that the entire outer circumference of the pole body 51 mentioned here does not include the outer circumference of the first body 511. Because the first body 511 of the pole body 51 protrudes from the plastic 40, and the outer circumference of the first body 511 is not connected to any structure.

[0175] For example, a recessed structure b may be provided on the outer circumference of the second body 512 of the pole 50. Alternatively, a recessed structure b may be provided on a portion of the outer circumference of the third body 513 of the pole 50. Alternatively, a recessed structure b may be provided on both the outer circumference of the second body 512 and the portion of the outer circumference of the third body 513 of the pole 50. The position of the recessed structure b needs to be provided corresponding to the position of the raised structure a of the upper plastic 40.

[0176] It can be understood that by respectively providing the protruding structure a and the recessed structure b on the pole 50 and the upper plastic 40 , it not only helps to align and connect the pole 50 and the upper plastic 40 more quickly, but also increases the connection stability between the pole 50 and the upper plastic 40 and prevents the pole 50 from shaking or sliding.

[0177] Second embodiment:

[0178] Please refer to Fig.15a , Fig.15b and Fig.16 , Fig.15a is along Figure 3 The second cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Fig.15b yes Fig.15a The enlarged view of the middle area L, Fig.16 yes Figure 3 The structure diagram of another structure of the sealing ring 30 of the top cover assembly 100 is shown at an angle. In this embodiment, the same contents as the first embodiment are not repeated. The difference from the first embodiment is that the structure of the inner wall of the second through hole 21 of the lower plastic 20 is different, and the structure of the outer side surface 31 of the sealing ring 30 is also different. In addition, the description of the top cover assembly 100 below can be applied to the first embodiment above without conflict.

[0179] The outer side surface 31 of the sealing ring 30 may include a first connecting surface 311 and a second connecting surface 312. The first connecting surface 311 and the second connecting surface 312 are both inclined relative to the thickness direction of the sealing ring 30, and both extend along the circumferential direction of the sealing ring 30. Among them, the circumferential direction of the sealing ring 30 is a direction that surrounds the central axis of the sealing ring 30. The first connecting surface 311 and the second connecting surface 312 are connected. The angle formed by the connection between the first connecting surface 311 and the second connecting surface 312 is the first angle A1. The first connecting surface 311 is closer to the top cover 10 relative to the second connecting surface 312. That is, the end of the first connecting surface 311 away from the second connecting surface 312 is close to the top surface 36 of the sealing ring 30. The end of the second connecting surface 312 away from the first connecting surface 311 is close to the bottom surface 32 of the sealing ring 30. Specifically, one end of the first connection surface 311 away from the second connection surface 312 is connected to the top surface 36 of the sealing ring 30, and / or one end of the second connection surface 312 away from the first connection surface 311 is connected to the bottom surface 32 of the sealing ring 30. Alternatively, the first connection surface 311 is spaced apart from the top surface 36 of the sealing ring 30, and the second connection surface 312 is spaced apart from the bottom surface 32 of the sealing ring 30. Exemplarily, the inclination direction of the first connection surface 311 relative to the thickness direction of the sealing ring 30 is opposite to the inclination direction of the second connection surface 312 relative to the thickness direction of the sealing ring 30.

[0180] The outer side surface 31 of the sealing ring 30 may also include a first transition surface 313. The first transition surface 313 may extend along the circumferential direction of the sealing ring 30. The first connecting surface 311 and the second connecting surface 312 may be connected through the first transition surface 313. The first transition surface 313 is used to prevent the connection between the first connecting surface 311 and the second connecting surface 312 from scratching the lower plastic 20 due to being too sharp. Exemplarily, the first transition surface 313 may be an arc surface. Of course, in other embodiments, the first connecting surface 311 and the second connecting surface 312 may also be directly connected. The connection between the first connecting surface 311 and the second connecting surface 312 extends along the circumferential direction of the sealing ring 30.

[0181] Please refer to Fig.15a , Fig.15b , Fig.17 and Fig.18 , Fig.17 yes Figure 3 The schematic diagram of another structure of the lower plastic 20 of the top cover assembly 100 is shown at an angle. Fig.18 is along Fig.17 Another schematic cross-sectional view of a portion of the structure of the lower plastic 20 cut along the cutting line DD is shown.

[0182] The inner wall of the second through hole 21 of the lower plastic 20 may include a first contact surface 211 and a second contact surface 212. The first contact surface 211 and the second contact surface 212 are both inclined relative to the thickness direction of the lower plastic 20, and both extend along the circumferential direction of the second through hole 21. The circumferential direction of the second through hole 21 is a direction that surrounds the central axis of the second through hole 21. The first contact surface 211 and the second contact surface 212 are connected. The angle formed by the connection between the first contact surface 211 and the second contact surface 212 is the second angle A2. One end of the first contact surface 211 away from the second contact surface 212 is close to the fourth surface 232 of the lower plastic 20. One end of the second contact surface 212 away from the first contact surface 211 is close to the third surface 231 of the lower plastic 20. Specifically, one end of the first contact surface 211 away from the second contact surface 212 is connected to the fourth surface 232 of the lower plastic 20, and / or one end of the second contact surface 212 away from the first contact surface 211 is connected to the third surface 231 of the lower plastic 20. Alternatively, the first contact surface 211 is spaced apart from the fourth surface 232 of the lower plastic 20, and the second contact surface 212 is spaced apart from the third surface 231 of the lower plastic 20. Exemplarily, the inclination direction of the first contact surface 211 relative to the thickness direction of the lower plastic 20 is opposite to the inclination direction of the second contact surface 212 relative to the thickness direction of the lower plastic 20.

[0183] The first contact surface 211 is in interference connection with at least part of the first connection surface 311 of the sealing ring 30, and / or the second contact surface 212 is in interference connection with at least part of the second connection surface 312 of the sealing ring 30. In some other embodiments, the first contact surface 211 is in interference connection with at least part of the second connection surface 312 of the sealing ring 30, and / or the second contact surface 212 is in interference connection with at least part of the first connection surface 311 of the sealing ring 30.

[0184] Exemplarily, the first contact surface 211 is in interference connection with part of the first connection surface 311 of the sealing ring 30, and there is a gap between the second contact surface 212 and the second connection surface 312 of the sealing ring 30. Alternatively, the first contact surface 211 is in interference connection with part of the first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with part of the second connection surface 312 of the sealing ring 30. Alternatively, the first contact surface 211 is in interference connection with part of the first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with all of the second connection surface 312 of the sealing ring 30. Alternatively, the first contact surface 211 is in interference connection with all of the first connection surface 311 of the sealing ring 30, and there is a gap between the second contact surface 212 and the second connection surface 312 of the sealing ring 30. Alternatively, the first contact surface 211 is in interference connection with all of the first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with part of the second connection surface 312 of the sealing ring 30. Alternatively, the first contact surface 211 is in interference connection with the entire first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with the entire second connection surface 312 of the sealing ring 30. Alternatively, there is a gap between the first contact surface 211 and the first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with a portion of the second connection surface 312 of the sealing ring 30. Alternatively, there is a gap between the first contact surface 211 and the first connection surface 311 of the sealing ring 30, and the second contact surface 212 is in interference connection with the entire second connection surface 312 of the sealing ring 30.

[0185] It can be understood that, by making the inner wall of the second through hole 21 of the lower plastic 20 include the first contact surface 211 and the second contact surface 212, and making the first contact surface 211 and the second contact surface 212 both be inclined surfaces inclined relative to the thickness direction of the lower plastic 20, the inner wall of the second through hole 21 of the lower plastic 20 can be made into a bent surface with an angle, thereby increasing the contact area between the lower plastic 20 and the sealing ring 30, and changing the shape of the electrolyte penetration path in the top cover assembly 100 from a straight line to a curved line, thereby further increasing the length of the penetration path, increasing the difficulty of the electrolyte penetrating into the top cover assembly 100, and further avoiding the electrolyte from penetrating into the gap between the top cover 10 and the pole 50, so that the top cover 10 and the pole 50 are electrically connected, resulting in the problem of the resistance of the pole 50 decreasing.

[0186] In this embodiment, the first angle A1 of the sealing ring 30 can be greater than the second angle A2 of the lower plastic 20. This can ensure that the sealing ring 30 and the lower plastic 20 are in interference connection, so that the outer side surface 31 of the sealing ring 30 and the inner wall of the second through hole 21 of the lower plastic 20 fit more closely, which is conducive to improving the connection stability and reliability between the sealing ring 30 and the lower plastic 20.

[0187] The inner wall of the second through hole 21 of the lower plastic 20 may also include a second transition surface 213. The second transition surface 213 may extend along the circumferential direction of the second through hole 21. The first contact surface 211 and the second contact surface 212 may be connected by the second transition surface 213. The second transition surface 213 is used to prevent the connection between the first contact surface 211 and the second contact surface 212 from scratching the sealing ring 30 due to being too sharp. Exemplarily, the second transition surface 213 may be an arc surface. Of course, in other embodiments, the first contact surface 211 and the second contact surface 212 may also be directly connected. The connection between the first contact surface 211 and the second contact surface 212 extends along the circumferential direction of the second through hole 21.

[0188] In a possible application scenario, please refer to Fig.15a and Fig.15b , one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is connected to the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is connected to the bottom surface 32 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 first increases and then decreases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 first increases and then decreases from the top surface 36 to the bottom surface 32. The outer side surface 31 of the sealing ring 30 is in a “C” shape, and the opening of the “C” faces the pole 50 .

[0189] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 first increases and then decreases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 of the lower plastic 20 in the thickness direction of the lower plastic 20 first increases and then decreases from the fourth surface 232 to the third surface 231. The inner wall of the second through hole 21 is in a "C" shape, and the opening of the "C" faces the outer side surface 31 of the sealing ring 30.

[0190] The first contact surface 211 of the lower plastic 20 is interference connected with the first connecting surface 311 and part of the first transition surface 313 of the sealing ring 30. There is a gap between the second contact surface 212 of the lower plastic 20 and the second connecting surface 312 of the sealing ring 30. In this embodiment, the first width W1 is greater than the second width W2.

[0191] It can be understood that by making the first contact surface 211 of the lower plastic 20 and the first connecting surface 311 and part of the first transition surface 313 of the sealing ring 30 in interference connection, the electrolyte can be blocked at the interference connection between the lower plastic 20 and the sealing ring 30, avoiding the electrolyte from entering the gap between the top cover 10 and the pole 50, and electrically connecting the top cover 10 and the pole 50, thereby reducing the problem of resistance of the pole 50.

[0192] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0193] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0194] Secondly, the sealing ring 30 is sleeved on the pole body 51 from above the pole body 51 of the pole 50, and the second connection surface 312 of the sealing ring 30 is first pressed into the second through hole 21 of the lower plastic 20, and then the first connection surface 311 of the sealing ring 30 is pressed into the second through hole 21 of the lower plastic 20, so that the sealing ring 30 and the lower plastic 20 are interference-connected, and the surface of the sealing ring 30 facing away from the upper plastic 40 is abutted against the pole base 52 of the pole 50. In some other embodiments, the first connection surface 311 of the sealing ring 30 can also be pressed into the second through hole 21 of the lower plastic 20, and then the second connection surface 312 of the sealing ring 30 can be pressed into the second through hole 21 of the lower plastic 20. That is, the sealing ring 30 does not need to be installed on the front and back sides.

[0195] Third embodiment:

[0196] Please refer to Fig.19a and Fig.19b , Fig.19a is along Figure 3 The third cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Fig.19b yes Fig.19a An enlarged view of the middle area M. In this embodiment, the same contents as those in the second embodiment are not repeated here. What is different from the second embodiment is that the first connecting surface 311 in the sealing ring 30 is arranged parallel to the thickness direction of the sealing ring 30. The first contact surface 211 in the lower plastic 20 is arranged parallel to the thickness direction of the lower plastic 20. That is, the first connecting surface 311 is arranged perpendicularly to the bottom surface 32 and / or the top surface 36 of the sealing ring 30 (allowing tolerance range). The first contact surface 211 is arranged perpendicularly to the fourth surface 232 and / or the third surface 231 of the lower plastic 20 (allowing tolerance range). In addition, the description of the top cover assembly 100 below can be applied to the first and second embodiments above unless there is a conflict.

[0197] It is understandable that by designing the first connection surface 311 of the sealing ring 30 at a right angle relative to the bottom surface 32, and by designing the first contact surface 211 of the lower plastic 20 at a right angle to the fourth surface 232, the right-angle surface of the sealing ring 30 can be directly dropped into the lower plastic 20 when the lower plastic 20 and the sealing ring 30 are assembled, without the need for pressing in advance. The right-angle design can also play a guiding role in the assembly process of the lower plastic 20 and the sealing ring 30. In summary, setting one of the interference surfaces of the sealing ring 30 and the lower plastic 20 as an inclined surface can increase the seepage path in the top cover assembly 100, and setting the other interference surface of the sealing ring 30 and the lower plastic 20 at a right angle can save pressing time and improve production efficiency.

[0198] In a possible application scenario, please continue to refer to Fig.19a and Fig.19b , one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is connected to the top surface 36 of the sealing ring 30. The first connection surface 311 is perpendicular to the bottom surface 32 and / or the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is connected to the bottom surface 32 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 remains unchanged from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 remains constant and then gradually decreases from the top surface 36 to the bottom surface 32. The outer side surface 31 of the sealing ring 30 is in a semi-C shape, and the opening of the C faces the pole 50.

[0199] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. The first contact surface 211 is perpendicular to the fourth surface 232 and / or the third surface 231 of the lower plastic 20. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 remains unchanged from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 in the thickness direction of the lower plastic 20 first remains constant and then gradually decreases from the fourth surface 232 to the third surface 231. The inner wall of the second through hole 21 of the lower plastic 20 is in a semi-C shape, and the opening of the C is toward the outer side surface 31 of the sealing ring 30.

[0200] The first contact surface 211 of the lower plastic 20 is interference connected with the first connecting surface 311 and the first transition surface 313 of the sealing ring 30. There is a gap between the second contact surface 212 of the lower plastic 20 and the second connecting surface 312 of the sealing ring 30. In this embodiment, the first width W1 is greater than the second width W2.

[0201] It is understandable that by making the first contact surface 211 of the lower plastic 20 and the first connection surface 311 and the first transition surface 313 of the sealing ring 30 in interference connection, the electrolyte can be blocked at the interference connection between the lower plastic 20 and the sealing ring 30, preventing the electrolyte from entering the gap between the top cover 10 and the pole 50, and electrically connecting the top cover 10 and the pole 50, thereby reducing the problem of the resistance of the pole 50.

[0202] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0203] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0204] Secondly, the sealing ring 30 is sleeved on the pole body 51 of the pole 50 from above, and the second connection surface 312 of the sealing ring 30 is first pressed into the second through hole 21 of the lower plastic 20, and then the first connection surface 311 of the sealing ring 30 can enter the second through hole 21 of the lower plastic 20 under the guiding effect, so that the sealing ring 30 and the lower plastic 20 are interference connected, and the surface of the sealing ring 30 facing away from the upper plastic 40 is abutted against the pole base 52 of the pole 50.

[0205] Fourth embodiment:

[0206] Please refer to Fig.20a and Fig.20b , Fig.20a is along Figure 3 The fourth cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Fig.20b yes Fig.20a An enlarged view of the middle area N. In this embodiment, the same contents as those in the second embodiment are not repeated here. What is different from the second embodiment is that the second connecting surface 312 in the sealing ring 30 is arranged parallel to the thickness direction of the sealing ring 30. The second contact surface 212 in the lower plastic 20 is arranged parallel to the thickness direction of the lower plastic 20. That is, the second connecting surface 312 is arranged perpendicularly to the bottom surface 32 and / or the top surface 36 of the sealing ring 30 (allowing tolerance range). The second contact surface 212 is arranged perpendicularly to the third surface 231 and / or the fourth surface 232 of the lower plastic 20 (allowing tolerance range). In addition, the description of the top cover assembly 100 below can be applied to the first to third embodiments above unless there is a conflict.

[0207] It is understandable that by designing the second connecting surface 312 of the sealing ring 30 to be at a right angle relative to the bottom surface 32, and by designing the second contact surface 212 of the lower plastic 20 to be at a right angle to the fourth surface 232, the right-angled surface of the sealing ring 30 can be directly inserted into the lower plastic 20 when the lower plastic 20 and the sealing ring 30 are assembled, thereby saving pressing time and improving production efficiency.

[0208] In a possible application scenario, please continue to refer to Fig.20a and Fig.20b , one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is connected to the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is connected to the bottom surface 32 of the sealing ring 30. The second connection surface 312 is arranged perpendicular to the bottom surface 32 and / or the top surface 36 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 remains unchanged from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32 and then remains unchanged. The outer side surface 31 of the sealing ring 30 is in a semi-C shape, and the opening of the C faces the pole 50.

[0209] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The second contact surface 212 is perpendicular to the third surface 231 and / or the fourth surface 232 of the lower plastic 20. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 remains unchanged from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231 and then remains unchanged. The inner wall of the second through hole 21 of the lower plastic 20 is in a semi-C shape, and the opening of the C faces the outer side surface 31 of the sealing ring 30.

[0210] The first contact surface 211 of the lower plastic 20 is interference connected with the first connecting surface 311 and the first transition surface 313 of the sealing ring 30. There is a gap between the second contact surface 212 of the lower plastic 20 and the second connecting surface 312 of the sealing ring 30. In this embodiment, the first width W1 is equal to the second width W2.

[0211] It is understandable that by making the first contact surface 211 of the lower plastic 20 and the first connection surface 311 and the first transition surface 313 of the sealing ring 30 in interference connection, the electrolyte can be blocked at the interference connection between the lower plastic 20 and the sealing ring 30, preventing the electrolyte from entering the gap between the top cover 10 and the pole 50, and electrically connecting the top cover 10 and the pole 50, thereby reducing the problem of the resistance of the pole 50.

[0212] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0213] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0214] Next, the sealing ring 30 is sleeved on the pole body 51 of the pole 50 from above, and the second connection surface 312 of the sealing ring 30 can be pressed into the second through hole 21 of the lower plastic 20 under the guiding effect, and then the first connection surface 311 of the sealing ring 30 can be interference-connected with the second contact surface 212 of the lower plastic 20. Then, the pole 50 is installed on the top cover 10, so that the top cover 10 compresses the sealing ring 30, and the surface of the sealing ring 30 facing away from the upper plastic 40 is abutted against the pole base 52 of the pole 50.

[0215] Fifth embodiment:

[0216] Please refer to Fig.21a and Figure 21b , Fig.21a is along Figure 3 A fifth cross-sectional schematic diagram of a partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Figure 21b yes Fig.21a : An enlarged view of the middle area O. In this embodiment, the same contents as those in the second embodiment are not repeated. The difference from the second embodiment is that the first angle A1 of the sealing ring 30 is smaller than the second angle A2 of the lower plastic 20. Specifically, the inclination direction of the first connecting surface 311 and the second connecting surface 312 of the sealing ring 30 in this embodiment relative to the thickness direction of the sealing ring 30 is opposite to the inclination direction of the first connecting surface 311 and the second connecting surface 312 of the sealing ring 30 relative to the thickness direction of the sealing ring 30 in the second embodiment. The inclination direction of the first contact surface 211 and the second contact surface 212 of the upper plastic 40 relative to the thickness direction of the lower plastic 20 in this embodiment is opposite to the inclination direction of the first contact surface 211 and the second contact surface 212 of the upper plastic 40 relative to the thickness direction of the lower plastic 20 in the second embodiment. The bending angle on the inner wall of the upper plastic 40 is located within the bending angle on the outer side surface 31 of the sealing ring 30. In addition, the description of the top cover assembly 100 below can be applied to the first to fourth embodiments above without conflict.

[0217] It is understandable that the present embodiment can also make the inner wall of the second through hole 21 of the lower plastic 20 and the outer side surface 31 of the sealing ring 30 be bent surfaces with an angle, so that the length of the penetration path is increased, and the purpose of increasing the difficulty of the electrolyte penetrating into the interior of the top cover assembly 100 is achieved, and the electrolyte is prevented from penetrating into the gap between the top cover 10 and the pole 50, so that the top cover 10 and the pole 50 are electrically connected, resulting in the problem of the resistance of the pole 50 decreasing.

[0218] In a possible application scenario, please continue to refer to Fig.21a and Figure 21b, one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is spaced from the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is spaced from the bottom surface 32 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 first decreases and then increases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 from the top surface 36 to the bottom surface 32 first remains unchanged, then decreases, then increases, and then remains unchanged. The outer side surface 31 of the sealing ring 30 is in a “C” shape, and the opening of the “C” faces the lower plastic 20 .

[0219] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 first decreases and then increases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 of the lower plastic 20 in the thickness direction of the lower plastic 20 first decreases and then increases from the fourth surface 232 to the third surface 231. The inner wall of the second through hole 21 is in a "C" shape, and the opening of the "C" is away from the sealing ring 30.

[0220] The first contact surface 211 of the lower plastic 20 is in interference connection with the first connection surface 311 of the sealing ring 30. The second contact surface 212 of the lower plastic 20 is in interference connection with the second connection surface 312 of the sealing ring 30. In this embodiment, the first width W1 is equal to the second width W2.

[0221] This embodiment can block the electrolyte at the interference fit between the lower plastic 20 and the sealing ring 30 to prevent the electrolyte from entering the gap between the top cover 10 and the pole 50 , and electrically connect the top cover 10 with the pole 50 , thereby reducing the resistance problem of the pole 50 .

[0222] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0223] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0224] Next, the sealing ring 30 is sleeved on the pole body 51 of the pole 50 from above, and the second connection surface 312 of the sealing ring 30 is pressed to abut against the second contact surface 212 of the lower plastic 20, and then the first connection surface 311 of the sealing ring 30 is pressed to abut against the first contact surface 211 of the lower plastic 20, so that the sealing ring 30 and the lower plastic 20 are interference-connected, and the surface of the sealing ring 30 facing away from the upper plastic 40 abuts against the pole base 52 of the pole 50. In some other embodiments, the sealing ring 30 can be installed without distinguishing between the front and back sides.

[0225] Sixth embodiment:

[0226] Please refer to Fig.22a and Figure 22b , Fig.22a is along Figure 3 The sixth cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Figure 22b yes Fig.22a An enlarged view of the middle area P. In this embodiment, the same contents as those in the fifth embodiment are not repeated here. What is different from the fifth embodiment is that the first connecting surface 311 in the sealing ring 30 is arranged parallel to the thickness direction of the sealing ring 30. The first contact surface 211 in the lower plastic 20 is arranged parallel to the thickness direction of the lower plastic 20. That is, the first connecting surface 311 is arranged perpendicularly to the bottom surface 32 and / or the top surface 36 of the sealing ring 30 (allowing tolerance range). The first contact surface 211 is arranged perpendicularly to the fourth surface 232 and / or the third surface 231 of the lower plastic 20 (allowing tolerance range). In addition, the description of the top cover assembly 100 below can be applied to the first to fifth embodiments above unless there is a conflict.

[0227] It is understandable that setting one of the interference surfaces between the sealing ring 30 and the lower plastic 20 as an inclined surface can increase the seepage path in the top cover assembly 100, and setting the other interference surface between the sealing ring 30 and the lower plastic 20 as a right angle can save pressing time and improve production efficiency.

[0228] In a possible application scenario, please continue to refer to Fig.22a and Figure 22b, one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is connected to the top surface 36 of the sealing ring 30. The first connection surface 311 is arranged perpendicularly to the bottom surface 32 and / or the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is arranged at a distance from the bottom surface 32 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 remains unchanged from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 gradually increases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 first remains constant, then gradually increases, and then remains constant from the top surface 36 to the bottom surface 32. The outer side surface 31 of the sealing ring 30 is in a semi-C shape, and the opening of the "C" faces the lower plastic 20.

[0229] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. The first contact surface 211 is perpendicular to the fourth surface 232 and / or the third surface 231 of the lower plastic 20. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 remains unchanged from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 gradually increases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 in the thickness direction of the lower plastic 20 first remains constant and then gradually increases from the fourth surface 232 to the third surface 231. The inner wall of the second through hole 21 of the lower plastic 20 is in a semi-C shape, and the opening of the C is away from the sealing ring 30.

[0230] The second contact surface 212 of the lower plastic 20 is interference connected with the second connection surface 312 of the sealing ring 30. There is a gap between the first contact surface 211 of the lower plastic 20 and the first connection surface 311 of the sealing ring 30. In this embodiment, the first width W1 is equal to the second width W2.

[0231] This embodiment can block the electrolyte at the interference fit between the lower plastic 20 and the sealing ring 30 , preventing the electrolyte from entering the gap between the top cover 10 and the pole 50 , thereby reducing the resistance of the pole 50 .

[0232] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0233] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0234] Secondly, the sealing ring 30 is sleeved on the pole body 51 of the pole 50 from above, and the second connecting surface 312 of the sealing ring 30 is first pressed into the second through hole 21 of the lower plastic 20, so that the second connecting surface 312 of the sealing ring 30 abuts against the second contact surface 212 of the lower plastic 20, and then the first connecting surface 311 of the sealing ring 30 can enter the second through hole 21 of the lower plastic 20 under the guiding effect, and the surface of the sealing ring 30 facing away from the upper plastic 40 abuts against the pole base 52 of the pole 50.

[0235] Seventh embodiment:

[0236] Please refer to Fig.23a and Figure 23b , Fig.23a is along Figure 3 The seventh cross-sectional schematic diagram of the partial structure of the top cover assembly 100 obtained by cutting along the cutting line AA shown in FIG. Figure 23b yes Fig.23a An enlarged view of the middle area Q. In this embodiment, the same contents as those in the fifth embodiment are not repeated here. What is different from the fifth embodiment is that the second connecting surface 312 in the sealing ring 30 is arranged parallel to the thickness direction of the sealing ring 30. The second contact surface 212 in the lower plastic 20 is arranged parallel to the thickness direction of the lower plastic 20. That is, the second connecting surface 312 is arranged perpendicularly to the bottom surface 32 and / or the top surface 36 of the sealing ring 30 (allowing tolerance range). The second contact surface 212 is arranged perpendicularly to the third surface 231 and / or the fourth surface 232 of the lower plastic 20 (allowing tolerance range). In addition, the description of the top cover assembly 100 below can be applied to the first to sixth embodiments above unless there is a conflict.

[0237] It is understandable that in this embodiment, the second connection surface 312 of the sealing ring 30 is designed to be at a right angle relative to the bottom surface 32, and the second contact surface 212 of the lower plastic 20 is designed to be at a right angle to the fourth surface 232, which can save pressing time and improve production efficiency. The other interference surface between the sealing ring 30 and the lower plastic 20 is set as a bevel to increase the liquid seepage path in the top cover assembly 100.

[0238] In a possible application scenario, please continue to refer to Fig.23a and Figure 23b , one end of the first connection surface 311 of the sealing ring 30 away from the second connection surface 312 is spaced from the top surface 36 of the sealing ring 30. One end of the second connection surface 312 of the sealing ring 30 away from the first connection surface 311 is connected to the bottom surface 32 of the sealing ring 30. The second connection surface 312 is perpendicularly arranged to the bottom surface 32 and / or the top surface 36 of the sealing ring 30. The first connection surface 311 and the second connection surface 312 are connected by a first transition surface 313. The first transition surface 313 is arc-shaped. The cross-sectional width of the first connection surface 311 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. The cross-sectional width of the second connection surface 312 in the thickness direction of the sealing ring 30 remains unchanged from the top surface 36 to the bottom surface 32. The cross-sectional width of the first transition surface 313 in the thickness direction of the sealing ring 30 gradually decreases from the top surface 36 to the bottom surface 32. That is, the cross-sectional width of the sealing ring 30 in the thickness direction of the sealing ring 30 first remains constant, then decreases, and then remains constant from the top surface 36 to the bottom surface 32. The outer side surface 31 of the sealing ring 30 is in a semi-C shape, and the opening of the "C" faces the lower plastic 20.

[0239] One end of the first contact surface 211 of the lower plastic 20 away from the second contact surface 212 is connected to the fourth surface 232. One end of the second contact surface 212 of the lower plastic 20 away from the first contact surface 211 is connected to the third surface 231. The second contact surface 212 is perpendicular to the third surface 231 of the lower plastic 20 and / or is arranged on the fourth surface 232. The first contact surface 211 and the second contact surface 212 are connected by a second transition surface 213. The second transition surface 213 is arc-shaped. The cross-sectional width of the first contact surface 211 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. The cross-sectional width of the second contact surface 212 in the thickness direction of the lower plastic 20 remains unchanged from the fourth surface 232 to the third surface 231. The cross-sectional width of the second transition surface 213 in the thickness direction of the lower plastic 20 gradually decreases from the fourth surface 232 to the third surface 231. That is, the cross-sectional width of the inner wall of the second through hole 21 in the thickness direction of the lower plastic 20 first remains constant, then decreases, and then remains constant in the direction from the fourth surface 232 to the third surface 231. The inner wall of the second through hole 21 of the lower plastic 20 is in a semi-C shape, and the opening of the C is away from the sealing ring 30.

[0240] The first contact surface 211 of the lower plastic 20 is interference connected with the first connection surface 311 of the sealing ring 30. There is a gap between the second contact surface 212 of the lower plastic 20 and the second connection surface 312 of the sealing ring 30. In this embodiment, the first width W1 is equal to the second width W2.

[0241] This embodiment can block the electrolyte at the interference fit between the lower plastic 20 and the sealing ring 30 , thereby preventing the problem of reduced resistance of the pole 50 from occurring.

[0242] In this embodiment, the assembly process of the top cover assembly 100 may include at least the following steps:

[0243] First, the pole 50 is installed on the lower plastic 20 , so that the pole body 51 of the pole 50 passes through the second through hole 21 of the lower plastic 20 , and the pole base 52 of the pole 50 abuts against the lower plastic 20 .

[0244] Secondly, the sealing ring 30 is sleeved on the pole body 51 from above the pole body 51 of the pole 50, and the second connection surface 312 of the sealing ring 30 can enter the second through hole 21 of the lower plastic 20 under the guiding effect. Then the pole 50 is installed on the top cover 10, so that the top cover 10 compresses the sealing ring 30, and the first connection surface 311 of the sealing ring 30 is connected with the second contact surface 212 of the lower plastic 20 through interference, so as to achieve the interference connection between the sealing ring 30 and the lower plastic 20. And the surface of the sealing ring 30 facing away from the upper plastic 40 is in contact with the pole base 52 of the pole 50.

[0245] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A top cover assembly, characterized in that: The top cover assembly comprises: A top cover, the top cover comprising a first surface, the first surface is used to face the battery cell, the top cover is provided with a first through hole, and the first through hole penetrates the top cover along the thickness direction of the top cover; A lower plastic, the lower plastic is connected to the first surface, the lower plastic is provided with a second through hole, the second through hole penetrates the lower plastic along the thickness direction of the lower plastic, and the second through hole is connected to the first through hole; A pole, the pole comprising a pole base and a pole body, the pole base being connected to the surface of the lower plastic away from the top cover, one end of the pole body being connected to the pole base, the pole body passing through the first through hole and the second through hole, and the other end of the pole body being protruding relative to the top cover; and A sealing ring is sleeved on the pole body, part of the sealing ring is located in the second through hole and elastically supported between the top cover and the pole base, and one end of the sealing ring located in the second through hole close to the lower plastic is interference connected with the lower plastic.

2. The top cover assembly according to claim 1, characterized in that: The sealing ring includes an outer side surface and a bottom surface, the outer side surface is the surface of one end of the sealing ring close to the lower plastic, the outer side surface is interference connected with the inner wall of the second through hole, the bottom surface is abutted against the pole base, and the outer side surface is vertically arranged to the bottom surface.

3. The top cover assembly according to claim 1, characterized in that: The sealing ring includes an outer side surface, which is a surface of the sealing ring close to one end of the lower plastic, and is interference-connected with the inner wall of the second through hole, and the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, and the first connecting surface and the second connecting surface are both inclined relative to the thickness direction of the sealing ring; The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, and the first contact surface and the second contact surface are both inclined relative to the thickness direction of the lower plastic; The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

4. The top cover assembly according to claim 3, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface.

5. The top cover assembly according to claim 3, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface.

6. The top cover assembly according to claim 1, characterized in that: The sealing ring includes an outer side surface, which is a surface of the sealing ring close to one end of the lower plastic, the outer side surface is interference-connected with the inner wall of the second through hole, and the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, the first connecting surface is arranged parallel to the thickness direction of the sealing ring, and the second connecting surface is arranged obliquely relative to the thickness direction of the sealing ring; The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, the first contact surface is arranged parallel to the thickness direction of the lower plastic, and the second contact surface is arranged obliquely relative to the thickness direction of the lower plastic; The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

7. The top cover assembly according to claim 6, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface.

8. The top cover assembly according to claim 6, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface.

9. The top cover assembly according to claim 1, characterized in that: The sealing ring includes an outer side surface, which is a surface of the sealing ring close to one end of the lower plastic, the outer side surface is interference-connected with the inner wall of the second through hole, and the outer side surface includes a first connecting surface and a second connecting surface connected to each other, the first connecting surface is close to the top cover relative to the second connecting surface, the first connecting surface is inclined relative to the thickness direction of the sealing ring, and the second connecting surface is parallel to the thickness direction of the sealing ring; The inner wall of the second through hole comprises a first contact surface and a second contact surface connected to each other, the first contact surface is closer to the top cover than the second contact surface, the first contact surface is inclined relative to the thickness direction of the lower plastic, and the second contact surface is parallel to the thickness direction of the lower plastic; The first contact surface is in interference connection with at least a portion of the first connection surface, and / or the second contact surface is in interference connection with at least a portion of the second connection surface.

10. The top cover assembly according to claim 9, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually increases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually increases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface.

11. The top cover assembly according to claim 9, characterized in that: The sealing ring further comprises a top surface and a bottom surface, the top surface and the bottom surface are arranged opposite to each other in the thickness direction of the sealing ring and are respectively connected to the two ends of the outer side surface of the sealing ring, the top surface abuts against the top cover, the bottom surface abuts against the pole base, the cross-sectional width of the first connecting surface in the thickness direction of the sealing ring gradually decreases from the top surface to the bottom surface, and the cross-sectional width of the second connecting surface in the thickness direction of the sealing ring remains unchanged from the top surface to the bottom surface; The lower plastic includes a third surface and a fourth surface, the third surface and the fourth surface are arranged opposite to each other in the thickness direction of the lower plastic and are respectively connected to the two ends of the inner wall of the second through hole, the fourth surface abuts against the top cover, the cross-sectional width of the first contact surface in the thickness direction of the lower plastic gradually decreases from the fourth surface to the third surface, and the cross-sectional width of the second contact surface in the thickness direction of the lower plastic remains unchanged from the fourth surface to the third surface.

12. The top cover assembly according to any one of claims 3 to 11, characterized in that: The angle formed by the first connecting surface and the second connecting surface is a first angle, the angle formed by the first contact surface and the second contact surface is a second angle, and the second angle is smaller than the first angle.

13. The top cover assembly according to any one of claims 1 to 11, characterized in that: The sealing ring includes a first state and a second state; When the sealing ring is in the first state, the sealing ring is separated from the lower plastic, and the cross-sectional width of the sealing ring along the thickness direction of the sealing ring is a first width; When the sealing ring is in the second state, the sealing ring is in interference connection with the lower plastic, and the cross-sectional width of the sealing ring along the thickness direction of the sealing ring is a second width, which is smaller than the first width.

14. The top cover assembly according to claim 13, characterized in that: The ratio of the difference between the first width and the second width to the first width is in the range of 3% to 5%.

15. The top cover assembly according to any one of claims 1 to 11, characterized in that: The sealing ring includes a sealing ring body and a connecting portion. The sealing ring body is sleeved on the pole body and spaced apart from the pole body and is interference connected with the lower plastic. One end of the connecting portion is connected to a side of the sealing ring body away from the lower plastic, and the other end of the connecting portion abuts against the pole body.

16. The top cover assembly according to any one of claims 1 to 11, characterized in that: The top cover is provided with a first mounting groove, the opening of the first mounting groove is located on the first surface, and the first mounting groove is coaxially arranged and communicated with the first through hole; The lower plastic includes a lower plastic body and a first convex portion, the lower plastic body is connected to the first surface, the first convex portion is fixedly connected to the surface of the lower plastic body facing the top cover, and is located in the first mounting groove, the lower plastic is also provided with a second mounting groove, the opening of the second mounting groove is located on the surface of the lower plastic body away from the top cover, the second mounting groove is coaxially arranged and communicated with the second through hole, and part of the pole base is located in the second mounting groove.

17. A battery, characterized in that: The battery comprises a battery cell, a shell and a top cover assembly as described in any one of claims 1 to 16, wherein the top cover assembly is connected to the shell and is arranged together with the shell to form a receiving space, and the battery cell is located in the receiving space.

18. An electrical equipment, characterized in that: The electric device comprises the battery as claimed in claim 17.

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