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 pole, a top cover, upper plastic, a pressing ring and a limiting body. The pole is connected to the top cover; the upper plastic is arranged on the pole in a sleeving mode, the upper plastic is located between the top cover and the pole in the radial direction of the pole, the upper plastic comprises an upper plastic body and a positioning hole, and the positioning hole is formed in the upper plastic body and penetrates through the upper plastic body in the thickness direction of the upper plastic; the compression ring is sleeved on the post terminal and is propped against one side, deviating from the top cover, of the upper plastic body; the limiting body penetrates through the positioning hole and is located between the pressing ring and the top cover in the thickness direction of the top cover, and in the circumferential direction of the limiting body, part of the outer surface of the limiting body is in interference fit with part of the inner surface of the positioning hole. According to the technical scheme, the overall assembling efficiency of the top cover assembly and the battery can be improved.

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 and the enhancement of people's environmental awareness, the application of batteries with recyclable characteristics, that is, batteries that can be recharged to activate active materials after discharge and continue to be used, is becoming more and more widespread. In the battery, the top cover assembly includes a pressure ring, an upper plastic, a limiter and a top cover. Among them, the limiter is embedded in the upper plastic and plays a supporting role between the pressure ring and the top cover.

[0003] However, in the prior art, the limiters are generally small and can be large in number. Therefore, during the assembly process of the top cover assembly, it is very easy for the limiters to be missed and reworked, which affects the assembly efficiency. Moreover, if the upper plastic rotates during the assembly process, resulting in errors in the assembly of the limiters or cracks, rework is also required, which greatly affects the assembly efficiency of the top cover assembly. Therefore, the existing assembly method between the limiter and the upper plastic results in a low assembly efficiency of the top cover assembly. Summary of the invention

[0004] The embodiments of the present application provide a top cover assembly, a battery, and an electrical device, which can improve the assembly efficiency of the top cover assembly and thus improve the overall assembly efficiency of the battery.

[0005] In a first aspect, the present application provides a top cover assembly, the top cover assembly comprising a pole, a top cover, an upper plastic, a pressure ring and a limiter;

[0006] The pole is connected to the top cover;

[0007] The upper plastic sleeve is arranged on the pole, and along the radial direction of the pole, the upper plastic is located between the top cover and the pole, and the upper plastic includes an upper plastic body and a positioning hole, and the positioning hole is arranged on the upper plastic body and penetrates the upper plastic body along the thickness direction of the upper plastic;

[0008] The pressure ring is sleeved on the pole and abuts against a side of the upper plastic body away from the top cover; and

[0009] The limiting body passes through the positioning hole and is located between the pressure ring and the top cover in the thickness direction of the top cover. In the circumferential direction of the limiting body, part of the outer surface of the limiting body is interference connected with part of the inner surface of the positioning hole.

[0010] It is understandable that in the technical solution of the present application, by making the outer surface of the limiting body in interference connection with the inner surface of the positioning hole, the connection between the limiting body and the upper plastic can be made more firm, greatly reducing the possibility of misalignment of the limiting body assembly caused by the rotation of the upper plastic, effectively preventing the risk of missing the installation of the limiting body, improving the assembly efficiency of the top cover assembly, and improving the use safety of the battery cell while avoiding rework. In addition, since only a part of the inner surface of the positioning hole is in interference connection with the outer surface of the limiting body, there will be a certain gap between the remaining parts of the inner surface of the limiting body and the inner surface of the positioning hole except for the interference connection part between the outer surface of the limiting body and the inner surface of the positioning hole. This enables the force exerted by the limiting body on the upper plastic when the interference amount is too large due to errors such as manufacturing tolerances and assembly tolerances during the assembly process of the limiting body and the upper plastic to be dispersed from the interference connection part between the outer surface of the limiting body and the inner surface of the positioning hole to the gap between the outer surface of the limiting body and the inner surface of the positioning hole, which is beneficial to avoiding the occurrence of cracking of the upper plastic caused by stress concentration at the interference connection part between the outer surface of the limiting body and the inner surface of the positioning hole, and increasing the connection stability and reliability between the limiting body and the upper plastic.

[0011] In a possible implementation manner, the positioning hole includes a first side surface and a second side surface. Along the circumferential direction of the positioning hole, the two ends of the first side surface are respectively connected to the two ends of the second side surface, and the first side surface extends in a bent manner between the two ends of the second side surface. The outer surface of the limiting body is in interference connection with a part of the first side surface and a part of the second side surface.

[0012] In a possible implementation manner, the shape of the positioning hole is an ellipse or an irregular circle.

[0013] In a possible implementation manner, the positioning hole includes at least three first side surfaces. Along the circumferential direction of the positioning hole, each first side surface is connected end to end with each other to enclose the positioning hole. Along the circumferential direction of the positioning hole, a part of the outer surface of the limiting body is in interference connection with at least three first side surfaces.

[0014] In a possible implementation manner, the positioning hole includes two first side surfaces and two second side surfaces. Along the circumferential direction of the positioning hole, each first side surface is connected between two adjacent second side surfaces. The outer surface of the limiting body is in interference connection with the two first side surfaces and / or the two second side surfaces.

[0015] In a possible implementation manner, the positioning hole includes at least three first side surfaces and at least three second side surfaces. Along the circumferential direction of the positioning hole, each first side surface is connected between two adjacent second side surfaces. The outer surface of the limiting body is in interference connection with at least three first side surfaces and / or at least three second side surfaces;

[0016] A maximum distance between the first side surface and the central axis of the limiting body is different from a maximum distance between the second side surface and the central axis of the limiting body.

[0017] In a possible implementation, the upper plastic body is provided with a first mounting groove, the opening of the first mounting groove is located on the surface of the upper plastic facing away from the top cover, the positioning hole passes through the bottom wall of the first mounting groove and the surface of the upper plastic body facing the top cover, and part of the pressure ring is located in the first mounting groove.

[0018] In a possible implementation manner, the positioning hole includes a first hole and a second hole sequentially arranged along the thickness direction of the upper plastic, the first hole includes the first side surface and the second side surface, and the second hole is coaxially arranged and connected to the first hole;

[0019] The second hole is disposed on the bottom wall of the first mounting groove away from the opening of the first hole, and the maximum dimension of the second hole in the length direction of the upper plastic gradually decreases from the upper plastic toward the top cover; and / or,

[0020] The opening of the second hole away from the first hole is arranged on the surface of the upper plastic facing the top cover, and the maximum dimension of the second hole in the length direction of the upper plastic gradually increases from the upper plastic toward the top cover.

[0021] In a possible implementation manner, the maximum dimension of the limiting body in the length direction of the top cover assembly gradually decreases from the pressure ring toward the upper plastic.

[0022] In a possible implementation manner, the melting point of the limiting body is greater than the melting point of the upper plastic.

[0023] In a possible implementation manner, the pressing ring is provided with a first groove, and the opening of the first groove is located on the surface of the pressing ring facing the upper plastic;

[0024] The top cover is provided with a second groove, and the opening of the second groove is located on the surface of the top cover facing the upper plastic;

[0025] One end of the limiting body is located in the first groove, and the other end of the limiting body is located in the second groove.

[0026] In a possible implementation manner, the pressure ring is provided with a first through hole, the first through hole penetrates the pressure ring along the thickness direction of the pressure ring, part of the pole is located in the first through hole, and the pressure ring is provided with a first notch, the first notch penetrates the outer side wall of the pressure ring in the radial direction, and connects the first groove and the outside of the pressure ring;

[0027] The top cover is provided with a second through hole which penetrates the top cover along the thickness direction of the top cover. Part of the pole column is located in the second through hole. The top cover is provided with a second notch which penetrates the inner wall of the second through hole and communicates the second groove and the second through hole.

[0028] In a possible implementation manner, the shortest distance between the bottom wall of the first groove and the bottom wall of the second groove is greater than the height of the limiting body.

[0029] In a possible implementation manner, a first air passage is formed in the gap region between the outer surface of the limiting body and the inner wall of the second groove, a second air passage is formed in the gap region between the outer surface of the limiting body and the inner surface of the positioning hole, a third air passage is formed in the gap region between the outer surface of the limiting body and the inner wall of the first groove, and a fourth air passage is formed in the gap region between the outer surface of the pressing ring and the inner wall of the first mounting groove. The first air passage, the second air passage, the third air passage and the fourth air passage are sequentially communicated to form at least part of the gas detection passage of the top cover assembly.

[0030] In a possible implementation manner, the top cover is further provided with a second mounting groove. The opening of the second mounting groove is located on the surface of the top cover facing the upper plastic. The second mounting groove is coaxially arranged with and communicated with the second through hole. Part of the upper plastic body is located in the second mounting groove. The opening of the second groove is located on the bottom wall of the second mounting groove.

[0031] The upper plastic further includes a first convex portion which is fixedly connected to the surface of the upper plastic body facing away from the pressing ring. The first convex portion is located in the second through hole.

[0032] The upper plastic is provided with a third through hole which penetrates the upper plastic body and the first convex portion along the thickness direction of the upper plastic. The third through hole is coaxially arranged with and communicated with the first mounting groove. The third through hole is connected between the first through hole and the second through hole and communicates the first through hole and the second through hole.

[0033] The pole column includes a pole column base and a pole column body. The pole column base is located on the side of the top cover facing away from the pressing ring. One end of the pole column body is fixedly connected to the pole column base. The pole column body passes through the first through hole, the second through hole and the third through hole. The other end of the pole column body extends out of the pressing ring.

[0034] In a possible implementation manner, the top cover assembly further includes a sealing ring which is sleeved on the pole column body. The sealing ring is connected between the top cover and the pole column base. The sealing ring is also connected between the first convex portion and the pole column base.

[0035] In a possible implementation manner, the top cover assembly further includes a lower plastic, the lower plastic is connected to a surface of the top cover facing away from the pressure ring, and a portion of the lower plastic is located between the top cover and the pole base.

[0036] In a second aspect, the present application also provides a battery, comprising a shell, a battery cell and a top cover assembly as described above, wherein the top cover assembly is connected to the shell and encloses the shell to form a storage space for the battery, and the battery cell is located in the storage space.

[0037] 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

[0038] Figure 1 is a schematic diagram of the structure of an energy storage system provided in an embodiment of the present application;

[0039] Figure 2 is a structural schematic diagram of a battery provided in an embodiment of the present application;

[0040] Figure 3 is a schematic structural diagram of a top cover assembly provided in the first embodiment of the present application;

[0041] Figure 4 yes Figure 3 An exploded structural diagram of the top cover assembly shown;

[0042] Figure 5a yes Figure 3 A schematic structural diagram of a pressure ring of the top cover assembly at an angle shown;

[0043] Figure 5b yes Figure 3 A schematic structural diagram of the pressure ring of the top cover assembly shown in another angle;

[0044] Figure 6a yes Figure 3 A schematic structural diagram of an angle of the upper plastic of the top cover assembly shown;

[0045] Figure 6b yes Figure 6a A schematic diagram of the structure of the upper plastic from another angle shown;

[0046] Figure 7 is along Figure 6a The schematic cross-sectional view obtained by cutting along the cutting line AA shown;

[0047] Figure 8a yes Figure 3 A schematic diagram of a first structural embodiment of the upper plastic portion of the top cover assembly shown;

[0048] Figure 8b yes Figure 3 A second structural schematic diagram of the upper plastic part of the top cover assembly shown;

[0049] Figure 8c yes Figure 3 A third structural schematic diagram of the upper plastic part of the top cover assembly shown;

[0050] Figure 8d yes Figure 3 A fourth structural schematic diagram of the upper plastic part of the top cover assembly shown;

[0051] Figure 8e yes Figure 3 A fifth structural schematic diagram of the upper plastic part of the top cover assembly shown;

[0052] Figure 8f yes Figure 6b A structural schematic diagram of the assembly of the upper plastic and the limiting body shown;

[0053] Figure 9 is along Figure 3 The schematic cross-sectional view obtained by cutting along the cutting line BB shown;

[0054] Figure 10 yes Figure 3 A schematic structural diagram of a limiter of the top cover assembly shown;

[0055] Figure 11 yes Figure 3 A schematic structural diagram of a top cover of the top cover assembly shown;

[0056] Figure 12a yes Figure 3 A schematic structural diagram of the lower plastic of the top cover assembly at an angle shown;

[0057] Figure 12b yes Figure 3 A schematic diagram of a partial structure of the lower plastic of the top cover assembly from another angle;

[0058] Figure 13 yes Figure 3 A schematic diagram of the structure of the pole of the top cover assembly shown;

[0059] Figure 14 This is a schematic diagram of the assembly of the limiting column and the upper plastic of the top cover assembly provided in the second embodiment of the present application;

[0060] Figure 15 is along Figure 14 The schematic cross-sectional view obtained by cutting along the cutting line CC shown;

[0061] Figure 16is a schematic structural diagram of a top cover assembly provided in a third embodiment of the present application;

[0062] Figure 17 is along Figure 16 A schematic cross-sectional view of a portion of the structure of the top cover assembly obtained by cutting along the cutting line DD shown;

[0063] Figure 18 yes Figure 16 A schematic structural diagram of a pressure ring of a top cover assembly shown;

[0064] Figure 19 It is a schematic diagram of the path of gas diffusion inside the top cover assembly.

[0065] Reference numerals:

[0066] Energy storage system 400, electric energy conversion device 410, first user load 420, second user load 430, electric equipment 300, battery 200, housing 210, battery cell 220, top cover assembly 100, pressure ring 10, upper plastic 20, top cover 30, limiter 40, explosion-proof valve assembly F, explosion-proof valve 50, explosion-proof valve protection sheet 60, pole 70, lower plastic 80, sealing ring 90, first through hole 11, first groove 12, upper plastic body 21, first convex portion 22 , third through hole 23, first mounting groove 211, positioning hole 212, first surface 201, second surface 202, first notch 121, first inclined surface 2111, second inclined surface 221, first hole 2121, second hole 2122, first side surface 2121a, second side surface 2121b, third side surface 2121c, second mounting groove 31, second through hole 32, second groove 33, explosion-proof hole 34, injection hole 35, mark 36, second notch 331, first end 41, second end 42, pole body 71, pole base 72, first sub-portion 711, second sub-portion 712, third sub-portion 713, lower plastic body 81, second convex portion 82, fourth through hole 811, fifth through hole 821, third inclined surface 822, gas detection channel S, first air channel S1, second air channel S2, third air channel S3, fourth air channel S4, gap T1, gap T2, gap T3, gap T4, gap T5, gap T6, gap T7, gap T 8. The maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212, the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212, the maximum distance L3 between the first side surface 2121a and the central axis of the limiting body 40, the maximum distance L4 between the second side surface 2121b and the central axis of the limiting body 40, the shortest distance D between the bottom wall of the first groove 12 and the bottom wall of the second groove 33, and the height H of the limiting body 40. DETAILED DESCRIPTION

[0067] For the convenience of understanding, first, the terms involved in the embodiments of the present application are explained.

[0068] And / or: It is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0069] Multiple: It means two or more than two.

[0070] Connection: It should be understood in a broad sense. For example, when A is connected to B, it can be that A is directly connected to B, or A is indirectly connected to B through an intermediate medium.

[0071] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. It should be noted that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0072] The embodiments of the present application provide a top cover assembly, a battery, and an electrical device.

[0073] Since the energy required by people has strong temporality and spatiality, in order to rationally utilize energy and improve the energy utilization rate, it is necessary to store one form of energy in the same or converted into another form of energy through a medium or device, and then release it in a specific energy form based on future application needs. As is well known, the current generation of green electric energy generally depends on photovoltaic, wind power, water potential, etc. Wind energy and solar energy generally have problems such as strong intermittency and large volatility, which will cause the power grid to be unstable, insufficient power during peak electricity consumption, too much electricity during low electricity consumption, and unstable voltage will also damage the power. Therefore, due to insufficient power demand or insufficient power grid acceptance capacity, the problem of "abandoning wind and light" may be caused. To solve these problems, energy storage is required. That is, the electric energy is converted into other forms of energy and stored through physical or chemical means, and the energy is converted into electric energy and released when needed. Simply put, energy storage is similar to a large "power bank", which stores electric energy when photovoltaic and wind energy are sufficient and releases the stored power when needed.

[0074] Taking electrochemical energy storage as an example, the embodiments of the present application provide an electrical device 300. A group of chemical batteries are provided inside the electrical device 300, mainly using the chemical elements in the chemical batteries as energy storage media. The charge and discharge process is accompanied by chemical reactions or changes of the energy storage media. Simply put, the electric energy generated by wind energy and solar energy is stored in the chemical batteries, and the stored electricity is released when the external electricity usage reaches the peak, or transferred to places with tight electricity for use.

[0075] The current energy storage application scenarios are relatively extensive, including energy storage on the power generation side, energy storage on the grid side, energy storage for renewable energy grid connection, and energy storage on the user side, etc. The types of corresponding electrical equipment 300 include:

[0076] The large energy storage container applied in the energy storage scenario on the grid side can be used as a high-quality active and reactive power regulation power source in the grid, realizing the load matching of electric energy in time and space, enhancing the consumption capacity of renewable energy, and being of great significance in grid system standby, alleviating the power supply pressure during peak loads, and peak shaving and frequency modulation.

[0077] The small and medium-sized energy storage cabinets applied in the industrial and commercial energy storage scenarios on the user side and the household small energy storage boxes applied in the household energy storage scenarios on the user side mainly operate in the mode of "peak shaving and valley filling". Since there is a large price difference in electricity charges at peak and valley positions according to the electricity consumption demand, after the user has the electrical equipment 300, in order to reduce costs, usually during the low electricity price period, the energy storage cabinet / box is charged; during the high electricity price period, the electricity in the electrical equipment 300 is released for use to achieve the purpose of saving electricity charges. In addition, in remote areas and areas with high incidence of natural disasters such as earthquakes and hurricanes, the existence of household electrical equipment 300 is equivalent to the user providing a backup power source for himself and the grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0078] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of the energy storage system 400 provided by the embodiment of the present application. The embodiment of the present application is described by taking the household energy storage scenario in the energy storage on the user side as an example, and the electrical equipment 300 of the present application is not limited to the household energy storage scenario.

[0079] The embodiment of the present application provides an energy storage system 400. The energy storage system 400 includes an electric energy conversion device 410, a first user load 420, a second user load 430, and an electrical equipment 300. The electrical equipment 300 is a small energy storage box and can be installed on an outdoor wall in a wall-mounted manner. Specifically, the photovoltaic panel can convert solar energy into electric energy during the low electricity price period, and the electrical equipment 300 is used to store the electric energy and supply street lamps and household appliances for use during the high electricity price period, or supply power when the grid is powered off / out of power.

[0080] Among them, the electrical device 300 may include, but is not limited to, a single battery, a battery module, a battery pack, a battery system, etc. When the electrical device 300 includes multiple batteries, the multiple batteries are electrically connected and are all located inside the housing of the electrical device 300, and can be protected by the housing from external environmental interference. Exemplarily, the multiple batteries are arranged at intervals. The multiple batteries can be connected in series, in parallel, or in a hybrid connection of series and parallel to achieve a larger capacity and power. The embodiments of the present application are described by taking the electrical device 300 including a battery as an example, but it should be understood that the electrical device 300 is not limited thereto.

[0081] Please refer to Figure 2 , Figure 2 which is a schematic structural diagram of the battery 200 provided by the embodiment of the present application.

[0082] For the convenience of description hereinafter, 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 in pairs.

[0083] The battery 200 may include a top cover assembly 100, a housing 210, and an electric core 220. The top cover assembly 100 is connected to the housing 210 and encloses with the housing 210 to form an accommodation space of the battery 200. The electric core 220 is located inside the accommodation space of the battery 200. Exemplarily, the top cover assembly 100 can be welded to the housing 210 by welding. The housing 210 can be made of a metal material, such as aluminum alloy, etc. The battery can be a cylindrical battery or a square battery, etc.

[0084] It should be noted that Figure 2 the purpose is only to schematically describe the connection relationship of the top cover assembly 100, the housing 210, and the electric core 220, and does not specifically limit the connection positions, specific structures, and quantities of each device. And the structure schematically shown in the embodiments 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 more or fewer components than Figure 2 shown, or combine some components, or split some components, or have different component arrangements. Figure 2 The components shown can be implemented in hardware, software, or a combination of software and hardware.

[0085] It can be understood that in the related art, the top cover assembly includes a pressing ring, an upper plastic, a limiting body, a top cover, etc. Among them, the limiting body is generally installed in the upper plastic and is used to position and connect the corresponding positions between the pressing ring and the top cover to prevent misalignment during installation. However, the limiting body generally has a small size and a large number, so during the assembly process of the top cover assembly, it is very easy to have the phenomenon of missing installation of the limiting body and rework, which affects the assembly efficiency. Moreover, if the upper plastic rotates during the assembly process, resulting in incorrect installation of the limiting body, rework is also required, greatly affecting the assembly efficiency of the top cover assembly.

[0086] In summary, currently, the assembly method between the limiting body and the upper plastic easily leads to a low assembly efficiency of the top cover assembly.

[0087] Therefore, an embodiment of the present application provides a top cover assembly 100, which can improve the assembly efficiency of the top cover assembly 100, and further improve the overall assembly efficiency of the battery 200. The structure of the top cover assembly 100 will be described in detail below through three specific embodiments.

[0088] First Embodiment:

[0089] Please refer to Figure 3 and Figure 4 , Figure 3 which is a schematic structural diagram of the top cover assembly 100 provided by the first embodiment of the present application, Figure 4 and Figure 3 is an exploded structural diagram of the top cover assembly 100 shown in

[0090] The top cover assembly 100 may include a pressing ring 10, an upper plastic 20, a top cover 30, a limiting body 40, an explosion-proof valve assembly F, a terminal 70, a lower plastic 80, and a sealing ring 90. The upper plastic 20 is connected to the top cover 30. The pressing ring 10 is connected to the side of the upper plastic 20 facing away from the top cover 30. The limiting body 40 passes through the upper plastic 20 and is located between the pressing ring 10 and the top cover 30. The explosion-proof valve assembly F is connected to the top cover 30 and is used for pressure relief protection of the battery 200. The lower plastic 80 is connected to the surface of the top cover 30 facing away from the upper plastic 20. The terminal 70 passes through the lower plastic 80, the top cover 30, the upper plastic 20, and the pressing ring 10. The terminal 70 can be used as an electrode lead of the battery 200 to achieve electrical connection between the battery 200 and external devices. The sealing ring 90 is sleeved on the terminal 70 and is located between the top cover 30 and the terminal 70. The sealing ring 90 is also located between the upper plastic 20 and the terminal 70.

[0091] Among them, the explosion-proof valve assembly F may include an explosion-proof valve 50 and an explosion-proof valve protection piece 60. Both the explosion-proof valve 50 and the explosion-proof valve protection piece 60 are connected to the explosion-proof hole 34 and are sequentially arranged in the thickness direction (the illustrated Z direction) of the top cover 30. The explosion-proof valve protection piece 60 covers the explosion-proof valve 50. The number of the upper plastics 20 may be two, and the two upper plastics 20 are installed at intervals on both sides in the length direction (the illustrated X direction) of the top cover 30. The number of the pressure rings 10 may be two, and the two pressure rings 10 are respectively installed on the two upper plastics 20. The number of the pole columns 70 may be two, and the two pole columns 70 may be a negative pole column and a positive pole column respectively. The two pole columns 70 may be arranged at intervals in the length direction of the top cover 30. Each pole column 70 passes through the lower plastic 80, the top cover 30, one upper plastic 20 and one pressure ring 10. The number of the sealing rings 90 may be two, and the two sealing rings 90 are respectively sleeved on the two pole columns 70.

[0092] Hereinafter, the structure of the top cover assembly 100 will be described by taking the assembly of one upper plastic 20, one pressure ring 10, one pole column 70 and one sealing ring 90 with the top cover 30 and the lower plastic 80 as an example. Without conflict, the description of the structure of one upper plastic 20, one pressure ring 10, one pole column 70 and one sealing ring 90 hereinafter can be applied to other upper plastics 20, pressure rings 10, pole columns 70 and sealing rings 90.

[0093] Please refer to Figure 5a and Figure 5b , Figure 5a is Figure 3 a schematic structural view of the pressure ring 10 of the top cover assembly 100 shown in Figure 5b is Figure 3 a schematic structural view of the pressure ring 10 of the top cover assembly 100 shown in another angle.

[0094] The pressure ring 10 is connected to the upper plastic 20. Specifically, the pressure ring 10 can be installed in the first mounting groove 211 of the upper plastic 20 and abut against the bottom wall of the first mounting groove 211. Part of the pressure ring 10 is located in the first mounting groove 211 of the upper plastic 20, and part of the pressure ring 10 is protruding relative to the upper plastic 20. The pressure ring 10 can be provided with a first through hole 11 and a first groove 12. The first through hole 11 penetrates the pressure ring 10 along the thickness direction of the pressure ring 10 (Z direction in the figure). The first through hole 11 can be used for the pole 70 to pass through and for accommodating the second sub-portion 712 of the pole 70. The opening of the first groove 12 is located on the surface of the pressure ring 10 close to the upper plastic 20. The concave direction of the first groove 12 can be from the pressure ring 10 to the upper plastic 20. The first groove 12 can be used to accommodate part of the limiter 40 to further limit the movement of the limiter 40 along the X direction, the Y direction and the Z direction. The number of the first grooves 12 can be one or more. When there are multiple first grooves 12, the multiple first grooves 12 can be arranged at intervals along the circumferential direction of the pressure ring 10. The circumferential direction of the pressure ring 10 is a direction around the central axis of the pressure ring 10. Each first groove 12 is used to accommodate a limiter 40. In some other embodiments, the pressure ring 10 may not be provided with the first groove 12, which is not strictly limited.

[0095] For example, the number of the first grooves 12 may be three, and the three first grooves 12 may be arranged at intervals along the circumferential direction of the pressing ring 10. The three first grooves 12 may be located at three equal points of the pressing ring 10 and arranged in a triangle on the pressing ring 10.

[0096] Please refer to Figure 6a , Figure 6b and Figure 7 , Figure 6a yes Figure 3 A structural schematic diagram of an angle of the upper plastic 20 of the top cover assembly 100 is shown. Figure 6b yes Figure 6a The structural diagram of the upper plastic 20 from another angle is shown. Figure 7 is along Figure 6a The schematic cross-sectional view is shown along the cutting line AA.

[0097] The upper plastic 20 is connected to the top cover 30. Specifically, the upper plastic 20 can be installed in the second installation groove 31 of the top cover 30. Part of the upper plastic 20 is located within the second installation groove 31 of the top cover 30, and part of the upper plastic 20 protrudes relative to the top cover 30. The upper plastic 20 can include a first surface 201 and a second surface 202. The first surface 201 is the surface of the upper plastic 20 facing the pressure ring 10, and the second surface 202 is the surface of the upper plastic 20 facing the top cover 30. The first surface 201 and the second surface 202 are arranged opposite to each other in the thickness direction (the illustrated Z direction) of the upper plastic 20. The upper plastic 20 can be provided with a first installation groove 211, a positioning hole 212, and a third through hole 23.

[0098] The opening of the first installation groove 211 can be located on the first surface 201. The first installation groove 211 can be recessed from the first surface 201 in the direction of the second surface 202. The first installation groove 211 can be used to install the pressure ring 10. There can be a gap between the inner peripheral surface of the first installation groove 211 and the outer peripheral surface of the pressure ring 10. Among them, the inner peripheral surface of the first installation groove 211 is the surface that surrounds the central axis of the first installation groove 211 for one week. The outer peripheral surface of the pressure ring 10 is the surface that surrounds the central axis of the pressure ring 10 for one week.

[0099] It can be understood that by having a gap between the inner peripheral surface of the first installation groove 211 and the outer peripheral surface of the pressure ring 10, the pressure ring 10 can be more conveniently and quickly installed in the first installation groove 211 of the upper plastic 20, thereby improving the installation efficiency of the top cover assembly 100. In addition, it can also provide a certain gas passage for the gas in the battery 200, facilitating the discharge of the gas in the battery 200.

[0100] The first installation groove 211 can include a first inclined surface 2111. The first inclined surface 2111 is connected to the opening of the first installation groove 211. The first inclined surface 2111 is arranged to surround along the circumferential direction of the first installation groove 211. Among them, the circumferential direction of the first installation groove 211 is the direction that surrounds the central axis of the first installation groove 211 for one week. The cross-sectional width of the first inclined surface 2111 in the thickness direction of the upper plastic 20 (that is, as Figure 7 shown, the cross-sectional width along the XY plane) gradually becomes smaller from the opening of the first installation groove 211 towards the bottom wall of the first installation groove 211. The first inclined surface 2111 can play a guiding role, helping to guide and install the pressure ring 10 into the first installation groove 211, reducing the installation difficulty and improving the installation efficiency.

[0101] The positioning hole 212 can penetrate through the upper plastic 20 along the thickness direction of the upper plastic 20. One end opening of the positioning hole 212 can be located at the bottom wall of the first installation groove 211, and the other end opening of the positioning hole 212 can be located at the second surface 202. That is, the positioning hole 212 can penetrate through the bottom wall of the first installation groove 211 and the second surface 202 along the thickness direction of the upper plastic 20. Among them, the bottom wall of the first installation groove 211 is disposed opposite to the opening of the first installation groove 211. The positioning hole 212 can communicate with the first installation groove 211. The positioning hole 212 can be used to install the limiting body 40. The number of the positioning holes 212 can be one or more. When the number of the positioning holes 212 is multiple, the multiple positioning holes 212 can be arranged at intervals along the circumferential direction of the upper plastic 20. Among them, the circumferential direction of the upper plastic 20 is the direction of surrounding the central axis of the upper plastic 20 for one week. Exemplarily, the number of the positioning holes 212 can be three. The three positioning holes 212 are respectively located at the trisection points of the circumferential direction of the upper plastic 20. The three positioning holes 212 can be arranged in a triangle on the upper plastic 20.

[0102] Hereinafter, the structure of one positioning hole 212 will be taken as an example to explain the positioning hole 212 in detail. Without conflict, the description of one positioning hole 212 hereinafter can be applied to other positioning holes 212.

[0103] In a possible implementation manner, please refer to Figure 8a , Figure 8a is Figure 3 the first structural schematic diagram of a partial structure of the upper plastic 20 of the top cover assembly 100 shown in. The shape of the positioning hole 212 can be oval or irregular circular. That is, the positioning hole 212 can be a special-shaped hole.

[0104] Among them, the irregular circular shape refers to a shape with deviation from the standard circle, which has an irregular shape, incomplete symmetry, and there are sharp corners, inflection points or discontinuities.

[0105] In another possible implementation manner, please refer to Figure 8b , Figure 8b is Figure 3 the second structural schematic diagram of a partial structure of the upper plastic 20 of the top cover assembly 100 shown in.

[0106] The positioning hole 212 can include a first side surface 2121a and a second side surface 2121b. Along the circumferential direction of the positioning hole 212, the two ends of the first side surface 2121a are respectively connected to the two ends of the second side surface 2121b. And the first side surface 2121a can be bent and extended between the two ends of the second side surface 2121b. That is, the positioning hole 212 can be a special-shaped hole.

[0107] In yet another possible implementation manner, please refer to Figure 8c ,Figure 8c Is Figure 3 The third structural schematic diagram of a partial structure of the upper plastic 20 of the top cover assembly 100 shown in

[0108] The positioning hole 212 may include at least three first side surfaces 2121a. Along the circumferential direction of the positioning hole 212, each first side surface 2121a is connected end to end with each other and encloses the positioning hole 212. Among them, the positioning hole 212 may be a special-shaped hole.

[0109] Exemplarily, the positioning hole 212 may be a triangular hole. For example, the shape of the positioning hole 212 may be an equilateral triangle, an isosceles triangle, a right triangle, or a triangle with unequal side lengths.

[0110] In another possible implementation manner, as Figure 8d And Figure 8e , Figure 8d Is Figure 3 The fourth structural schematic diagram of a partial structure of the upper plastic 20 of the top cover assembly 100 shown in Figure 8e Is Figure 3 The fifth structural schematic diagram of a partial structure of the upper plastic 20 of the top cover assembly 100 shown in

[0111] The positioning hole 212 may include at least two first side surfaces 2121a and at least two second side surfaces 2121b. Along the circumferential direction of the positioning hole 212, each first side surface 2121a is connected between two adjacent second side surfaces 2121b. The maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212 is different from the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212. Or, the maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212 may also be the same as the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212. There is no limitation on this.

[0112] In this embodiment, the positioning hole 212 may be a special-shaped hole.

[0113] Exemplarily, as Figure 8d Shown, the positioning hole 212 may be a rectangular hole. Or, as Figure 8e Shown, the positioning hole 212 may be an oblong hole.

[0114] Further, as Figure 8f Shown, Figure 8f Is Figure 6bA schematic structural diagram of the assembly of the upper plastic 20 and the limiting body 40 shown. The positioning hole 212 may include at least three first side surfaces 2121a and at least three second side surfaces 2121b. Along the circumferential direction of the positioning hole 212, each first side surface 2121a is connected between two adjacent second side surfaces 2121b. The maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212 is different from the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212. Alternatively, the maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212 may be the same as the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212. There is no limitation on this.

[0115] In this embodiment, the positioning hole 212 may be a special-shaped hole.

[0116] Exemplarily, as Figure 8f shown, the positioning hole 212 may be a hexagonal hole.

[0117] It should be noted that in this embodiment, the special-shaped holes described herein and below all refer to special-shaped holes with symmetry (such as geometric symmetry, rotational symmetry, etc.). The central axis of the positioning hole 212 refers to a straight line passing through the geometric center of the positioning hole 212 and coinciding with the axis of symmetry of the positioning hole 212. Of course, in some other embodiments, the special-shaped hole may also be a special-shaped hole with an irregular shape, and there is no strict limitation on this.

[0118] In a possible application scenario, please refer to Figure 7 and Figure 8f , the maximum distance L1 between the first side surface 2121a and the central axis of the positioning hole 212 is less than the maximum distance L2 between the second side surface 2121b and the central axis of the positioning hole 212. That is, the maximum distance L3 between the first side surface 2121a and the central axis of the limiting body 40 is less than the maximum distance L4 between the second side surface 2121b and the central axis of the limiting body 40. Specifically, the diameter of the inscribed circle formed by the first side surface 2121a is less than the maximum dimension of the limiting body 40 in the length direction (the illustrated X direction) of the top cover assembly 100. And / or, the diameter of the inscribed circle formed by the first side surface 2121a is less than the maximum dimension of the limiting body 40 in the width direction (the illustrated Y direction) of the top cover assembly 100. The first side surface 2121a is in contact with the outer surface of the limiting body 40. The diameter of the inscribed circle formed by the second side surface 2121b is greater than the maximum dimension of the limiting body 40 in the length direction of the top cover assembly 100. And / or, the diameter of the inscribed circle formed by the second side surface 2121b is greater than the maximum dimension of the limiting body 40 in the width direction of the top cover assembly 100. Exemplarily, as Figure 8fAs shown, the first side surface 2121a can be a flat surface. The second side surface 2121b can be an arc surface. The limiting body 40 can be cylindrical. The positioning hole 212 can include three first side surfaces 2121a and three second side surfaces 2121b. The diameter of the inscribed circle formed by the three first side surfaces 2121a is smaller than the diameter of the limiting body 40, and the diameter of the inscribed circle formed by the three second side surfaces 2121b is larger than the diameter of the limiting body 40.

[0119] In this application scenario, the positioning hole 212 can further include a third side surface 2121c. An adjacent first side surface 2121a and a second side surface 2121b can be transitionally connected through a third side surface 2121c, so as to prevent the connection between the first side surface 2121a and the second side surface 2121b from being too sharp and scratching the limiting body 40. Exemplarily, the third side surface 2121c can be an arc surface.

[0120] It can be understood that by making the diameter of the inscribed circle formed by the first side surface 2121a smaller than the maximum dimension of the limiting body 40 in the length and / or width direction of the top cover assembly 100, at least three first side surfaces 2121a of the positioning hole 212 can have an interference connection with the limiting body 40, so that the limiting body 40 is in close contact with and relatively fixed to the upper plastic 20, preventing the limiting body 40 from falling off and skewing during the assembly process of the top cover assembly 100. In addition, by making the diameter of the inscribed circle formed by the second side surface 2121b larger than the maximum dimension of the limiting body 40 in the length and / or width direction of the top cover assembly 100, there can be a gap between each second side surface 2121b and the limiting body 40. In addition, since each first side surface 2121a and the limiting body 40 are partially in interference connection, there is also a certain gap between each first side surface 2121a and the limiting body 40. When the interference amount is too large due to errors such as manufacturing tolerances and assembly tolerances during the assembly process of the upper plastic 20 and the limiting body 40, the force exerted on the upper plastic 20 by the extrusion of the limiting body 40 can be dispersed from the interference connection between the limiting body 40 and the first side surface 2121a to the gap between the limiting body 40 and the first side surface 2121a, and then to the gap between the limiting body 40 and the second side surface 2121b, avoiding the occurrence of cracking of the upper plastic 20 caused by stress concentration, where the force exerted on the upper plastic 20 by the extrusion of the limiting body 40 can be dispersed in the directions indicated by the three double-headed arrows inside Figure 8f In summary, by making the partial inner surface of the positioning hole 212 in interference connection with the limiting body 40, it can not only ensure the interference fit between the limiting body 40 and the upper plastic 20, making the limiting body 40 and the upper plastic 20 tightly fixed, but also avoid the risk of cracking of the upper plastic 20.

[0121] In this embodiment, the positioning hole 212 may include a first hole 2121 and a second hole 2122 that are sequentially arranged in the thickness direction of the upper plastic 20. The first hole 2121 and the second hole 2122 are coaxially arranged and communicated with each other. The first hole 2121 includes the first side surface 2121a and the second side surface 2121b described above. One opening of the second hole 2122 is communicated with the first hole 2121, and the other opening of the second hole 2122 is away from the first hole 2121.

[0122] The opening of the second hole 2122 away from the first hole 2121 may be arranged on the bottom wall of the first mounting groove 211. The maximum dimension of the second hole 2122 in the length direction (the illustrated X direction) of the upper plastic 20 gradually decreases from the upper plastic 20 to the direction of the top cover 30. Alternatively, the opening of the second hole 2122 away from the first hole 2121 may be arranged on the second surface 202. The maximum dimension of the second hole 2122 in the length direction of the upper plastic 20 gradually increases from the upper plastic 20 to the direction of the top cover 30.

[0123] It should be noted that the change in the maximum dimension of the second hole 2122 in the length direction of the upper plastic 20 described above also applies to the change in the maximum dimension of the second hole 2122 in the width direction (the illustrated Y direction) of the upper plastic 20.

[0124] In summary, the maximum dimension of the second hole 2122 in the length direction and / or the width direction of the upper plastic 20 gradually increases from the first hole 2121 to the direction away from the first hole 2121. There may be a gap between the inner surface of the second hole 2122 and the outer surface of the limiting body 40.

[0125] It can be understood that since the maximum dimension of the second hole 2122 in the length direction and / or the width direction of the upper plastic 20 gradually increases from the first hole 2121 to the direction away from the first hole 2121. Therefore, even if the limiting body 40 is initially inclined and misaligned with the positioning hole 212 to a certain extent, under the guiding action of the second hole 2122, the limiting body 40 can still be conveniently and quickly guided into the positioning hole 212, so that the limiting body 40 is fixedly connected to the upper plastic 20. In addition, since the limiting body 40 only contacts some inner surfaces of the first hole 2121 of the positioning hole 212 and is spaced from the inner surface of the second hole 2122 of the positioning hole 212. Therefore, on the basis of ensuring the connection strength between the limiting body 40 and the positioning hole 212, the interference contact area between the limiting body 40 and the positioning hole 212 can be reduced, the assembly difficulty of the top cover assembly 100 can be reduced, and the assembly efficiency of the top cover assembly 100 can be improved.

[0126] In this embodiment, the shape of the second hole 2122 may be the same as that of the first hole 2121. Specifically, the cross-sectional shape of the second hole 2122 along the thickness direction of the upper plastic body 21 is the same as the cross-sectional shape of the first hole 2121 along the thickness direction of the upper plastic body 21. That is, as Figure 6b shown, the cross-sectional shape of the second hole 2122 along the XY plane is the same as the cross-sectional shape of the first hole 2121 along the XY plane. In other embodiments, the shape of the second hole 2122 may also be different from that of the first hole 2121.

[0127] The number of the second holes 2122 may be one or two. Among them, when the number of the second holes 2122 is one, that is, the positioning hole 212 only includes one second hole 2122, the opening of the second hole 2122 away from the first hole 2121 is located on the bottom wall of the first installation groove 211 or on the second surface 202. When the number of the second holes 2122 is two, that is, the positioning hole 212 includes two second holes 2122, the opening of one second hole 2122 away from the first hole 2121 is located on the bottom wall of the first installation groove 211, and the opening of the other second hole 2122 away from the first hole 2121 is located on the second surface 202. The first hole 2121 is connected between the two second holes 2122 and communicates with the two second holes 2122.

[0128] In this embodiment, the upper plastic 20 may be provided with a third through hole 23. The third through hole 23 penetrates the upper plastic 20 along the thickness direction of the upper plastic 20. The third through hole 23 may be coaxially arranged with the first installation groove 211. In the thickness direction of the upper plastic, the third through hole 23 may communicate with the first installation groove 211. When the upper plastic 20 is connected to the pressure ring 10, the third through hole 23 of the upper plastic 20 may be coaxially arranged and communicated with the first through hole 11 of the pressure ring 10.

[0129] The third through hole 23 may be used for the pole column 70 to pass through and for accommodating the third sub - part 713 of the pole column 70. Among them, the positioning hole 212 may be located at the outer edge of the third through hole 23. When the number of the positioning holes 212 is multiple, the multiple positioning holes 212 may be arranged at intervals along the circumferential direction of the third through hole 23 at the outer edge of the third through hole 23. The circumferential direction of the third through hole 23 may be the direction around the central axis of the third through hole 23 for one week.

[0130] Please refer to Figure 6a 、 Figure 6b and Figure 7 , a part of the upper plastic 20 is located between the top cover 30 and the pole column 70 to separate the top cover 30 and the pole column 70, so as to avoid short - circuit caused by direct contact between the top cover 30 and the pole column 70. Specifically, the upper plastic 20 may include a connected upper plastic body 21 and a first convex part 22.

[0131] The upper plastic body 21 can be installed in the second installation groove 31 of the top cover 30. The upper plastic body 21 can include the first surface 201 and the second surface 202 described above, and is provided with the first installation groove 211 and the positioning hole 212 described above.

[0132] The first protrusion 22 may be annular and fixedly connected to the second surface 202 of the upper plastic body 21. The first protrusion 22 may also be installed in the second through hole 32 of the top cover 30 and be located between the inner surface of the second through hole 32 of the top cover 30 and the outer surface of the third sub-portion 713 of the pole 70. The outer peripheral surface of the first protrusion 22 may abut against the inner surface of the second through hole 32. The first protrusion 22 is used to isolate the pole 70 and the top cover 30 to avoid direct contact between the pole 70 and the top cover 30, which may cause danger. The first protrusion 22 and the upper plastic body 21 may cooperate to form the third through hole 23 described above, and the third through hole 23 may penetrate the first protrusion 22 and the upper plastic body 21 along the thickness direction of the upper plastic. Among them, the first protrusion 22 and the upper plastic body 21 may be an integrated structure formed by connecting in a manner such as integral molding.

[0133] A second inclined surface 221 is provided at one end of the first protrusion 22 away from the upper plastic body 21. The second inclined surface 221 can be arranged around the circumferential direction of the first protrusion 22. The circumferential direction of the first protrusion 22 is a direction around the central axis of the first protrusion 22. The cross-sectional width of the second inclined surface 221 along the thickness direction of the upper plastic 20 gradually decreases from the end where the first protrusion 22 is connected to the upper plastic body 21 to the end where the first protrusion 22 is away from the upper plastic body 21. The second inclined surface 221 can play a guiding role, which helps to install the first protrusion 22 in the second through hole 32 of the top cover 30, reduce the difficulty of installing the upper plastic 20 and the top cover 30, and improve the installation efficiency of the upper plastic 20 and the top cover 30.

[0134] Please refer to Figure 9 and Figure 10 , Figure 9 is along Figure 3 The schematic cross-sectional view obtained by cutting along the cutting line BB shown in FIG. Figure 10 yes Figure 3 A schematic structural diagram of the limiting body 40 of the top cover assembly 100 is shown.

[0135] The limiting body 40 is passed through the positioning hole 212 of the upper plastic 20 and is located between the pressure ring 10 and the top cover 30. The limiting body 40 may include a first end 41 and a second end 42. The first end 41 faces the pressure ring 10. The second end 42 faces the top cover 30. The first end 41 protrudes from the bottom wall of the first mounting groove 211 of the upper plastic 20. The second end 42 protrudes from the second surface 202 of the upper plastic 20. The first end 41 of the limiting body 40 is located in the first groove 12 of the pressure ring 10, and is abutted or spaced with the pressure ring 10. The second end 42 of the limiting body 40 is located in the second groove 33 of the top cover 30, and is abutted or spaced with the top cover 30. The cross-sectional width of the limiting body 40 along the thickness direction (Z direction in the figure) of the top cover assembly 100 can be the same from the first end 41 to the second end 42.

[0136] It can be understood that by positioning the first end 41 of the limit body 40 in the first groove 12 of the pressure ring 10 and positioning the second end 42 of the limit body 40 in the second groove 33 of the top cover 30, the pressure ring 10 and the top cover 30 can cooperate with each other to limit the movement of the limit body 40 from opposite sides of the limit body 40, thereby further improving the installation stability and reliability of the limit body 40.

[0137] In some other embodiments, the first groove 12 may not be provided in the pressing ring 10, nor the second groove 33 may be provided in the top cover 30. In this case, the first end 41 of the limiting body 40 abuts against or is spaced apart from the surface of the pressing ring 10 close to the upper plastic 20. The second end 42 of the limiting body 40 abuts against or is spaced apart from the bottom wall of the second installation groove 31 of the top cover 30.

[0138] In this embodiment, the melting point of the limiting body 40 may be greater than the melting point of the upper plastic 20 .

[0139] It is understandable that during the use of the battery 200, thermal runaway may occur due to mechanical damage, excessively high ambient temperature, improper operation, etc., causing the upper plastic 20 to completely melt at high temperature and lose its support and insulation function, resulting in the pressure ring 10 and the pole 70 sinking, and leakage and short circuit in the battery 200. In this embodiment, by making the melting point of the limiter 40 greater than the melting point of the upper plastic 20, even if the battery cell 220 undergoes thermal runaway and causes the upper plastic 20 to melt at high temperature, the limiter 40 can effectively support the pressure ring 10, avoiding the problem of excessive leakage of the electrolyte in the battery cell 220 due to the excessive sinking of the pole 70, thereby improving the working reliability of the battery 200.

[0140] Please refer to Figure 8a , Figure 8f and Figure 9, a part of the outer surface of the limiting body 40 is in interference connection with at least a part of the inner surface of the positioning hole 212. Specifically, the outer surface of the limiting body 40 is spaced from the second hole 2122 of the positioning hole 212. That is, there is a gap between the outer surface of the limiting body 40 and the second hole 2122 of the positioning hole 212. A part of the outer surface of the limiting body 40 is in interference connection with a part of the inner surface of the first hole 2121 of the positioning hole 212. Specifically, as Figure 8a shown, when the positioning hole 212 only includes one side surface (that is, the shape of the positioning hole 212 is oval or irregular circular), a part of the outer surface of the limiting body 40 is in interference connection with a part of this side surface of the positioning hole 212. Or, as Figure 8f shown, when the positioning hole 212 includes at least two side surfaces, a part of the outer surface of the limiting body 40 is in interference connection with a part of at least two side surfaces of the positioning hole 212.

[0141] The interference connection situation between the limiting body 40 and the positioning hole 212 will be described in detail below through some embodiments.

[0142] In a possible embodiment, as Figure 8d and Figure 8e shown, the positioning hole 212 may include two first side surfaces 2121a and two second side surfaces 2121b. The outer surface of the limiting body 40 is in interference connection with the two first side surfaces 2121a, and there is a gap between the outer surface of the limiting body 40 and the two second side surfaces 2121b. Among them, the maximum distance L3 between the first side surface 2121a and the central axis of the limiting body 40 is less than the maximum distance L4 between the second side surface 2121b and the central axis of the limiting body 40.

[0143] In another possible embodiment, as Figure 8f shown, the positioning hole 212 may include three first side surfaces 2121a and three second side surfaces 2121b. The outer surface of the limiting body 40 is in interference connection with the three first side surfaces 2121a, and there is a gap between the outer surface of the limiting body 40 and the three second side surfaces 2121b. Among them, the maximum distance L3 between the first side surface 2121a and the central axis of the limiting body 40 is less than the maximum distance L4 between the second side surface 2121b and the central axis of the limiting body 40.

[0144] Or, the outer surface of the limiting body 40 may also be in interference connection with all the first side surfaces 2121a and all the second side surfaces 2121b. That is, the outer surface of the limiting body 40 is in interference connection with all the side surfaces of the positioning hole 212. It should be noted that at this time, the outer surface of the limiting body 40 is in partial contact with each side surface of the positioning hole 212. That is, except for the interference connection parts between the limiting body 40 and each side surface of the positioning hole 212, there are certain gaps between the remaining parts of the limiting body 40 and each side surface of the positioning hole 212.

[0145] Exemplarily, as Figure 8b shown, the positioning hole 212 may include a first side surface 2121a and a second side surface 2121b. The outer surface of the limiting body 40 is in interference connection with a part of the first side surface 2121a and a part of the second side surface 2121b. Among them, the maximum distance L3 between the first side surface 2121a and the central axis of the limiting body 40 is equal to the maximum distance L4 between the second side surface 2121b and the central axis of the limiting body 40.

[0146] Exemplarily, as Figure 8c shown, the positioning hole 212 may include three first side surfaces 2121a. The outer surface of the limiting body 40 is in interference connection with a part of each first side surface 2121a. Among them, the distance between each first side surface 2121a and the central axis of the limiting body 40 is equal.

[0147] It can be understood that the limiting body in the top cover assembly is generally installed in the upper plastic and plays a supporting role between the pressing ring and the top cover. However, in the prior art, the limiting body is generally small and the number can be large. Therefore, during the assembly process of the top cover assembly, it is very easy to have the phenomenon that the limiting body is missed in assembly and rework is required, which affects the assembly efficiency. Moreover, if the upper plastic rotates during the assembly process, resulting in incorrect assembly of the limiting body, rework is also required, which greatly affects the assembly efficiency of the top cover assembly. Therefore, the existing assembly method between the limiting body and the upper plastic results in a low assembly efficiency of the top cover assembly.

[0148] Thus, in this embodiment, by making the outer surface of the limiting body 40 in interference connection with the inner surface of the positioning hole 212, the connection between the limiting body 40 and the upper plastic 20 can be made more firm, greatly reducing the possibility of misalignment of the limiting body 40 caused by the rotation of the upper plastic 20, effectively preventing the risk of missing the installation of the limiting body 40, improving the assembly efficiency of the top cover assembly 100, and improving the use safety of the battery cell 220 while avoiding rework. In addition, since the outer surface of the limiting body 40 is only in interference connection with a part of the inner surface of the positioning hole 212, there will be a certain gap between the remaining part of the inner surface of the limiting body 40 and the inner surface of the positioning hole 212 except for the interference connection part between the outer surface of the limiting body 40 and the inner surface of the positioning hole 212. This enables the force exerted by the limiting body 40 on the upper plastic 20 when the interference amount is too large due to manufacturing tolerances, assembly tolerances and other error conditions during the assembly process of the limiting body 40 and the upper plastic 20 to be dispersed from the interference connection part between the outer surface of the limiting body 40 and the inner surface of the positioning hole 212 to the gap between the outer surface of the limiting body 40 and the inner surface of the positioning hole 212. It is beneficial to avoid the occurrence of cracking of the upper plastic 20 caused by stress concentration at the interference connection part between the outer surface of the limiting body 40 and the inner surface of the positioning hole 212, and increases the connection stability and reliability between the limiting body 40 and the upper plastic 20.

[0149] Moreover, the positioning hole 212 can be a special-shaped hole. This design enables the efficient identification of the positioning hole 212 during the assembly process of the limiting body 40 and accurately installs the limiting body 40 into the positioning hole 212, thereby further improving the assembly efficiency of the top cover assembly 100.

[0150] Please refer to Figure 9 and Figure 11 , Figure 11 which Figure 3 is a schematic structural view of the top cover 30 of the top cover assembly 100 shown in

[0151] The top cover 30 can extend in the X direction and is provided with a second installation groove 31 and a second through hole 32. The opening of the second installation groove 31 is located on the surface of the top cover 30 facing the upper plastic 20. The second installation groove 31 can be recessed from the surface of the top cover 30 facing the upper plastic 20 into the interior of the top cover 30. The second installation groove 31 can be used to install the upper plastic body 21 of the upper plastic 20. The second through hole 32 can penetrate the top cover 30 along the thickness direction of the top cover 30. The second through hole 32 is coaxially arranged and communicated with the second installation groove 31. When the top cover assembly 100 is assembled, the second through hole 32 can also be communicated with the third through hole 23 of the upper plastic 20, so that the third through hole 23 of the upper plastic 20 is connected between the first through hole 11 of the pressure ring 10 and the second through hole 32 of the top cover 30 and communicates the first through hole 11 of the pressure ring 10 and the second through hole 32 of the top cover 30. The second through hole 32 is used for the pole column 70 to pass through and for accommodating the third sub-part 713 of the pole column 70. The inner surface of the second through hole 32 can be spaced from the outer peripheral surface of the third sub-part 713 of the pole column 70. Wherein, the outer peripheral surface of the third sub-part 713 is the surface surrounding the central axis of the third sub-part 713 for one week. The gap area between the inner surface of the second through hole 32 and the outer peripheral surface of the third sub-part 713 of the pole column 70 can be used to accommodate the first convex part 22 of the upper plastic 20.

[0152] Wherein, the number of the second installation grooves 31 can be two, and the two second installation grooves 31 are spaced apart in the length direction (the illustrated X direction) of the top cover 30. Each second installation groove 31 can be used to install one upper plastic 20. The number of the second through holes 32 can be two, and the two second through holes 32 can be spaced apart in the length direction of the top cover 30 and are respectively coaxially arranged and communicated with the two second installation grooves 31. Each second through hole 32 is used for a pole column 70 to pass through and for accommodating a third sub-part 713 of a pole column 70.

[0153] The top cover 30 may also be provided with an explosion-proof hole 34 and a liquid injection hole 35. The explosion-proof hole 34 is located between two second mounting grooves 31 and is spaced from both of the second mounting grooves 31. The explosion-proof hole 34 may penetrate the top cover 30 in the thickness direction of the top cover 30 and is used to connect with the explosion-proof valve assembly F. The liquid injection hole 35 penetrates the top cover 30 in the thickness direction of the top cover 30. The liquid injection hole 35 may be provided between the explosion-proof hole 34 and the second mounting groove 31 and is spaced from both the explosion-proof hole 34 and the second mounting groove 31. The top cover 30 may also be provided with a mark 36. The mark 36 is adjacent to the second through hole 32. The mark 36 is used to mark the positive or negative polarity of the pole 70 mounted in the second through hole 32 of the top cover 30, so as to more efficiently align the second through hole 32 with the positive-polarity pole 70 or the negative-polarity pole 70, and help the pole 70 of the corresponding polarity to be installed in the corresponding second through hole 32.

[0154] Exemplarily, the number of the marks 36 may be two, and the two marks 36 are respectively adjacent to and spaced from the two second through holes 32. A '+' shaped mark 36 is provided around the second through hole 32 connected to the positive-polarity pole 70. A '-' shaped mark 36 is provided around the second through hole 32 connected to the negative-polarity pole 70.

[0155] Please refer to Figure 5b 、 Figure 9 and Figure 11 The top cover 30 may also be provided with a second groove 33. The opening of the second groove 33 is located at the bottom wall of the second mounting groove 31 and communicates with the second mounting groove 31. Wherein, the bottom wall of the second mounting groove 31 is opposite to the opening of the second mounting groove 31. The second groove 33 may be recessed from the bottom wall of the second mounting groove 31 in a direction away from the opening of the second mounting groove 31. The second groove 33 is used to accommodate part of the limiting body 40 to further play a role in restricting the movement of the limiting body 40 in the X direction, Y direction and Z direction.

[0156] In a possible implementation manner, the top cover 30 may be provided with a second notch 331. The second notch 331 may face the second through hole 32. Specifically, the second notch 331 may penetrate the inner wall of the second through hole 32. The second notch 331 communicates the second groove 33 and the second through hole 32. That is, the second groove 33 may be an open groove open on one side. The second notch 331 is the open end of the second groove 33. Exemplarily, the second groove 33 may be an arched groove open on one side. Wherein, the open end of the second groove 33 faces the second through hole 32. That is, the second notch 331 faces the second through hole 32.

[0157] It can be understood that if the second groove 33 is set as a closed groove with its side walls closed, during the processing of the battery 200, the side wall of the second groove 33 close to the second through hole 32 may be deformed or drawn due to being too thin, thereby generating additional metal debris and falling into the interior of the battery 200, causing a short circuit in the battery 200. Therefore, by setting the side wall of the second groove 33 close to the second through hole 32 to be open, it is possible to avoid the problem of short circuit inside the battery 200 caused by metal debris generated due to the too thin side wall in the edge area of the second groove 33.

[0158] In some other embodiments, the top cover 30 may also not be provided with the second notch 331, and no strict limitation is imposed thereon.

[0159] In this embodiment, the number of the second grooves 33 may be the same as that of the limiting bodies 40, which may also be one or more. When the number of the second grooves 33 is multiple, the multiple second grooves 33 may be arranged at intervals along the circumferential direction of the second mounting groove 31 and are all located at the outer edge of the second through hole 32. Among them, the circumferential direction of the second mounting groove 31 is the direction that surrounds the central axis of the second mounting groove 31 for one week. Each second groove 33 is used to accommodate one limiting body 40.

[0160] In some other embodiments, the top cover 30 may also not be provided with the second groove 33, and no strict limitation is imposed thereon.

[0161] Please refer to Figure 9 、 Figure 12a and Figure 12b , Figure 12a is Figure 3 a schematic structural diagram of a certain angle of the lower plastic 80 of the top cover assembly 100 shown in Figure 12b is Figure 3 a partial schematic structural diagram of another angle of the lower plastic 80 of the top cover assembly 100 shown in

[0162] The lower plastic 80 is connected to the surface of the top cover 30 facing away from the pressure ring 10. Part of the lower plastic 80 is located between the top cover 30 and the pole base 72 of the pole post 70. The lower plastic 80 may be provided with a fourth through hole 811. The fourth through hole 811 may penetrate through the lower plastic 80 along the thickness direction of the lower plastic 80 (the Z direction shown in the figure). The fourth through hole 811 may be used for the pole post 70 to pass through and accommodate the third sub - part 713 of the pole post 70. The inner surface of the fourth through hole 811 may be spaced from the outer peripheral surface of the third sub - part 713 of the pole post 70. The gap area between the inner surface of the fourth through hole 811 and the outer peripheral surface of the third sub - part 713 of the pole post 70 may be used to accommodate the sealing ring 90. Among them, the number of the fourth through holes 811 may be two, and the two fourth through holes 811 may be arranged at intervals in the length direction of the lower plastic 80 (the X direction shown in the figure). Each fourth through hole 811 is used for a pole post 70 to pass through and accommodate a third sub - part 713 of a pole post 70.

[0163] In this embodiment, the lower plastic 80 may include a lower plastic body 81 and a second convex portion 82. The lower plastic body 81 may extend along the X direction and is provided with the fourth through hole 811 described above. The fourth through hole 811 may penetrate the lower plastic body 81 along the thickness direction (illustrated Z direction) of the lower plastic body 81. The surface of the lower plastic body 81 facing away from the top cover 30 may be in contact with the pole base 72 of the pole 70.

[0164] The second convex portion 82 is fixedly connected to the surface of the lower plastic body 81 facing away from the top cover 30. The second convex portion 82 may be disposed around the outer edge of the fourth through hole 811 and is coaxially disposed with the fourth through hole 811. Among them, the number of the second convex portions 82 may be two, and the two second convex portions 82 may be spaced apart in the length direction of the lower plastic 80. Each second convex portion 82 is disposed around the outer edge of a fourth through hole 811 and is coaxially disposed with a fourth through hole 811.

[0165] The second convex portion 82 may be provided with a fifth through hole 821. The fifth through hole 821 penetrates the second convex portion 82 along the thickness direction of the second convex portion 82. The fifth through hole 821 is coaxially disposed and communicated with the fourth through hole 811. The cross-sectional width of the fifth through hole 821 along the thickness direction of the lower plastic 80 is greater than the cross-sectional width of the fourth through hole 811 along the thickness direction of the lower plastic 80. The fifth through hole 821 may be used for the pole 70 to pass through and accommodate a part of the pole base 72 of the pole 70. The inner surface of the fifth through hole 821 may be in contact with a part of the outer peripheral surface of the pole base 72. The depth of the fifth through hole 821 may be less than the thickness of the pole base 72. Therefore, in the direction from the top cover 30 to the lower plastic 80, the pole base 72 extends out of the fifth through hole 821, that is, the pole base 72 protrudes relative to the second convex portion 82.

[0166] A third inclined surface 822 is provided at one end of the second convex portion 82 away from the lower plastic body 81. The third inclined surface 822 may be disposed along the circumferential direction of the fifth through hole 821. The cross-sectional width of the third inclined surface 822 along the thickness direction of the lower plastic 80 may gradually increase from the lower plastic body 81 to the direction of the second convex portion 82.

[0167] Please refer to Figure 9 and Figure 13 , Figure 13 is Figure 3 a schematic structural diagram of the pole 70 of the top cover assembly 100 shown in

[0168] In this embodiment, the terminal post 70 is installed on the lower plastic 80, the top cover 30, the upper plastic 20, and the pressing ring 10. Opposite ends of the terminal post 70 protrude relative to the pressing ring 10 and the lower plastic 80, respectively. Specifically, the terminal post 70 may include a terminal post body 71 and a terminal post base 72. The terminal post base 72 is located on a side of the top cover 30 away from the pressing ring 10. One end of the terminal post body 71 is fixedly connected to the terminal post base 72. The terminal post body 71 passes through the second through-hole 32 of the top cover 30, the third through-hole 23 of the upper plastic 20, and the first through-hole 11 of the pressing ring 10, and the other end of the terminal post body 71 extends out of the pressing ring 10.

[0169] The terminal post body 71 may include a first sub-portion 711, a second sub-portion 712, and a third sub-portion 713. The first sub-portion 711, the second sub-portion 712, and the third sub-portion 713 are connected in sequence and arranged coaxially. The third sub-portion 713 is connected to the terminal post base 72, and the second sub-portion 712 is connected between the third sub-portion 713 and the first sub-portion 711. The first sub-portion 711, the second sub-portion 712, the third sub-portion 713, and the terminal post base 72 may be an integral structure formed by means such as integral molding.

[0170] The diameters of the first sub-portion 711, the second sub-portion 712, and the third sub-portion 713 of the terminal post 70 are different. Among them, the diameter of the first sub-portion 711 is smaller than the diameter of the second sub-portion 712, the diameter of the second sub-portion 712 is smaller than the diameter of the third sub-portion 713, and the diameter of the third sub-portion 713 is smaller than the diameter of the terminal post base 72.

[0171] It can be understood that by setting the terminal post body 71 into three parts with different diameters, the pressing ring 10, the upper plastic 20, the top cover 30, the lower plastic 80, and the sealing ring 90 can be better installed on the corresponding parts, avoiding installation misalignment. Moreover, the diameter of the terminal post base 72 is larger than the diameter of the terminal post body 71, which can support the top cover assembly 100 connected to the terminal post body 71 and prevent it from slipping.

[0172] In this embodiment, the first sub-portion 711 of the terminal post 70 protrudes relative to a surface of the pressing ring 10 away from the upper plastic 20. The second sub-portion 712 of the terminal post 70 is located in the first through-hole 11 of the pressing ring 10. The third sub-portion 713 of the terminal post 70 is located in the third through-hole 23 of the upper plastic 20, the second through-hole 32 of the top cover 30, and the fourth through-hole 811 of the lower plastic 80. A part of the terminal post base 72 of the terminal post 70 is located in the fifth through-hole 821 of the lower plastic 80, and a part protrudes relative to the second protrusion 82 of the lower plastic 80.

[0173] Please refer to Figure 9 , the sealing ring 90 is sleeved on the terminal post body 71. The sealing ring 90 is connected between the top cover 30 and the terminal post base 72. The sealing ring 90 is also connected between the first protrusion 22 of the upper plastic 20 and the terminal post base 72. It should be noted that Figure 9Among them, the overlapping area between the sealing ring 90 and the top cover 30 is the area where interference occurs between the compressed sealing ring 90 and the top cover 30. The overlapping area between the sealing ring 90 and the first convex portion 22 of the upper plastic 20 is the area where interference occurs between the compressed sealing ring 90 and the first convex portion 22 of the upper plastic 20.

[0174] It can be understood that by providing the sealing ring 90, the airtightness between the pole column 70, the upper plastic 20 and the top cover 30 can be enhanced, and the electrolyte of the battery cell 220 can be prevented from leaking to the outside of the battery 200, which is beneficial to improving the overall safety performance of the battery 200.

[0175] Specifically, the sealing ring 90 can be sleeved on the third sub-portion 713 of the pole column 70 and is located within the fourth through-hole 811 of the lower plastic 80. The inner peripheral surface of the sealing ring 90 abuts against the outer peripheral surface of the third sub-portion 713. The outer peripheral surface of the sealing ring 90 is spaced apart from the inner surface of the fourth through-hole 811. The sealing ring 90 has elasticity. One side of the sealing ring 90 can abut against and squeeze the first convex portion 22 of the upper plastic 20 and the top cover 30, and the other side of the sealing ring 90 can abut against and squeeze the pole column base 72, thereby realizing the sealing between the top cover 30 and the pole column 70 in the axial direction. The number of the sealing rings 90 can be equal to the number of the pole columns 70, and can be one or more. When the number of the sealing rings 90 is multiple, each sealing ring 90 is sleeved on one pole column 70. Exemplarily, the number of the sealing rings 90 can be two, and the two sealing rings 90 are respectively sleeved on the two pole columns 70.

[0176] In this embodiment, the assembly process of the top cover assembly 100 can at least include the following steps:

[0177] First, the pole column body 71 of the pole column 70 sleeved with the sealing ring 90 is sequentially passed through the lower plastic 80 and the top cover 30, so that the pole column base 72 abuts against the lower plastic 80, and the sealing ring 90 abuts between the top cover 30 and the pole column base 72 of the pole column 70.

[0178] Secondly, the limiting body 40 is inserted into the positioning hole 212 of the upper plastic 20, and the limiting body 40 is in interference connection with the positioning hole 212 of the upper plastic 20.

[0179] Then, the upper plastic 20 is sleeved on the pole column 70 and abuts against the top cover 30 and the sealing ring 90.

[0180] Finally, the pressure ring 10 is placed and pressured, and after the sealing ring 90 is deformed, the pressure ring 10 and the pole column 70 are welded.

[0181] Second Embodiment:

[0182] Please refer to Figure 14 and Figure 15 , Figure 141 is a schematic diagram of the assembly of the limiting body 40 and the upper plastic 20 of the top cover assembly 100 provided in the second embodiment of the present application. Figure 15 is along Figure 14 The schematic cross-sectional view is shown along the cutting line CC.

[0183] In this embodiment, the same contents as those in the first embodiment are not repeated, and the difference from the first embodiment is that the structure of the stopper 40 is different. In addition, the description of the top cover assembly 100 below can be applied to the first embodiment above without conflict.

[0184] The maximum dimension of the stopper 40 in the length direction of the top cover assembly 100 gradually decreases from the pressure ring 10 to the upper plastic 20. That is, the maximum dimension of the stopper 40 in the length direction of the top cover assembly 100 gradually decreases from the first end 41 to the second end 42. Exemplarily, the shape of the stopper 40 is a frustum.

[0185] It should be noted that the above-mentioned change in the maximum dimension of the limiting body 40 in the length direction of the top cover assembly 100 is also applicable to the change in the maximum dimension of the limiting body 40 in the width direction of the top cover assembly 100 .

[0186] It is understandable that, during the process of installing the limiter 40 on the upper plastic 20, the smaller second end 42 of the limiter 40 can be quickly aligned with the positioning hole 212 and placed in the positioning hole 212 of the upper plastic 20. As the installation process of the limiter 40 proceeds, the limiter 40 in contact with the positioning hole 212 becomes larger and larger. The limiter 40 abuts and squeezes the first hole 2121 of the positioning hole 212, thereby forming an interference fit fixation. After the limiter 40 is assembled in place, the upper plastic 20 and the limiter 40 abut against the top cover 30 respectively. That is, the second end 42 of the limiter 40 abuts against the bottom wall of the second groove 33 of the top cover 30. The surface of the upper plastic body 21 close to the top cover 30 abuts against the bottom wall of the second installation groove 31 of the top cover 30. The first convex portion 22 of the upper plastic 20 is located in the second through hole 32 of the top cover 30. This greatly facilitates the alignment of the upper plastic 20 and the top cover 30 during assembly of the top cover assembly 100 , reduces the assembly accuracy requirements of the top cover assembly 100 , and improves the production efficiency of the top cover assembly 100 .

[0187] Third embodiment:

[0188] Please refer to Figure 16 and Figure 17 , Figure 16 is a schematic structural diagram of a top cover assembly 100 provided in the third embodiment of the present application, Figure 17 is along Figure 16 The section line DD shown is a schematic cross-sectional view of a portion of the structure of the top cover assembly 100 .

[0189] In this embodiment, the same content as that in the first embodiment will not be elaborated again. The difference from the first embodiment is that the top cover assembly 100 may further include a gas detection channel S. In addition, the descriptions of the top cover assembly 100 in the following text can be applied to the first embodiment and the second embodiment above without conflict.

[0190] Please refer to Figure 17 and Figure 18 , Figure 18 which is Figure 16 a schematic structural view of the clamping ring 10 of the top cover assembly 100 shown.

[0191] In this embodiment, the clamping ring 10 may be provided with a first notch 121. The first notch 121 faces away from the first through hole 11. Specifically, the first notch 121 penetrates the outer wall in the radial direction of the clamping ring 10. The first notch 121 communicates the first groove 12 and the outside of the clamping ring 10. That is, the first groove 12 can be an open groove open on one side. The first notch 121 is the open end of the first groove 12. Exemplarily, the first groove 12 can be an arched groove open on one side. Among them, the open end of the first groove 12 faces away from the first through hole 11. That is, the first notch 121 faces away from the first through hole 11.

[0192] In some other embodiments, the first notch 121 may also face the first through hole 11.

[0193] In this embodiment, the first notch 121 may be disposed opposite to the second notch 331 of the top cover 30 in the radial direction of the limiting body 40. That is, the open directions of the first groove 12 and the second groove 33 are opposite. It can be understood that by connecting the limiting body 40 with the first groove 12 and the second groove 33 with opposite open directions, it can effectively prevent the limiting body 40 from sliding relative to the clamping ring 10 and the top cover 30, so that the limiting body 40 can have good connection stability and reliability.

[0194] Please refer to Figure 17 , the shortest distance D between the bottom wall of the first groove 12 and the bottom wall of the second groove 33 may be greater than the height H of the limiting body 40. Specifically, there is a gap between the bottom wall of the first groove 12 and the first end 41 of the limiting body 40, and / or there is a gap between the bottom wall of the second groove 33 and the second end 42 of the limiting body 40. This gap can increase the assembly tolerance space, so that even if there is a deviation during the assembly process of the battery 200, the limiting body 40 can still be normally supported between the clamping ring 10 and the top cover 30, preventing the clamping ring 10 from sinking too much and causing the electrolyte of the battery cell 220 to leak. It can also ensure that the limiting body 40 is not affected by the force in the height direction (the illustrated Z direction) of the battery 200, that is, ensure that the limiting body 40 is not affected by the force in the thickness direction of the top cover assembly 100, avoid damaging the limiting body 40 during the pressing and welding process of the clamping ring 10, improve the product yield, and reduce the production cost.

[0195] In addition, during the operation of the battery 200, the terminal post 70 generates heat, causing the surrounding materials (such as the upper plastic 20) to thermally expand. As a result, the sealing ring 90 is heated and rebounds, expanding the terminal post 70 downward, resulting in insufficient compression of the sealing ring 90 and failure of the sealing surface at the position of the terminal post 70, causing a liquid leakage phenomenon. In this embodiment, there is a gap between the limiting body 40 and the bottom wall of the first groove 12 of the pressing ring 10, and / or there is a gap between the limiting body 40 and the bottom wall of the second groove 33 of the top cover 30. When the upper plastic 20 softens and melts due to heat, this gap can provide a certain space, reducing the impact of the expansion of the upper plastic 20 on the compression state of the sealing ring 90. Thus, it is possible to avoid the problem of insufficient compression of the sealing ring 90 causing failure of the sealing surface and resulting in liquid leakage, improving the working reliability of the battery 200.

[0196] Among them, the size of the first groove 12 is larger than the size of the first end 41 of the limiting body 40, so that the first end 41 of the limiting body 40 is completely located in the first groove 12 to ensure the smoothness of the assembly between the limiting body 40 and the pressing ring 10 and the top cover 30. The size of the second groove 33 is larger than the size of the second end 42 of the limiting body 40, so that the second end 42 of the limiting body 40 is completely located in the second groove 33 to ensure the smoothness of the assembly between the limiting body 40 and the pressing ring 10 and the top cover 30.

[0197] In this embodiment, the top cover assembly 100 may include a gas detection channel S. The gas detection channel S may include a first air passage S1, a second air passage S2, a third air passage S3, and a fourth air passage S4. The first air passage S1, the second air passage S2, the third air passage S3, and the fourth air passage S4 are connected in sequence.

[0198] Specifically, the gap region between the outer surface of the limiting body 40 near the second end and the inner wall of the second groove 33 of the top cover 30 forms the first air passage S1. Among them, the outer surface of the limiting body 40 near the second end includes the outer peripheral surface of the limiting body 40 near the second end and the bottom surface of the limiting body 40. The inner wall of the second groove 33 includes the inner peripheral surface of the second groove 33 and the bottom wall of the second groove 33. The first air passage S1 may include a gap T1 and a gap T2. The gap T1 and the gap T2 are connected. Among them, the gap between the second end 42 of the limiting body 40 and the bottom wall of the second groove 33 is the gap T1. In addition, in order to make the second end 42 of the limiting body 40 completely located in the second groove 33, the size of the second groove 33 is larger than the size of the second end 42 of the limiting body 40. Therefore, there is a gap between the outer peripheral surface of the limiting body 40 and the inner peripheral surface of the second groove 33, and this gap is the gap T2.

[0199] A second air passage S2 is formed in the gap region between the outer surface of the middle section of the position-limiting body 40 and the inner surface of the positioning hole 212. Herein, the outer surface of the middle end of the position-limiting body 40 refers to the outer circumferential surface of the position-limiting body 40. The second air passage S2 may include a gap T3 and a gap T4. The gap T3 and the gap T4 are in communication. Specifically, the gap between the outer circumferential surface of the position-limiting body 40 and the second side surface 2121b of the first hole 2121 in the positioning hole 212 is the gap T3. The gap between the outer circumferential surface of the position-limiting body 40 and the inner circumferential surface of the second hole 2122 in the positioning hole 212 is the gap T4.

[0200] A third air passage S3 is formed in the gap region between the outer surface of the position-limiting body 40 near the first end and the inner wall of the first groove 12 of the pressure ring 10. Herein, the outer surface of the position-limiting body 40 near the first end includes the outer circumferential surface and the bottom surface of the position-limiting body 40. The inner wall of the first groove 12 includes the inner circumferential surface and the bottom wall of the first groove 12. The third air passage S3 may include a gap T5 and a gap T6. The gap T5 and the gap T6 are in communication. Among them, the gap between the first end 41 of the position-limiting body 40 and the bottom wall of the first groove 12 is the gap T5. In addition, in order to make the first end 41 of the position-limiting body 40 completely located in the first groove 12, the size of the first groove 12 is larger than the size of the first end 41 of the position-limiting body 40. Therefore, there is a gap between the outer circumferential surface of the position-limiting body 40 and the inner circumferential surface of the first groove 12, and this gap is the gap T6.

[0201] A fourth air passage S4 is formed in the gap region between the outer surface of the pressure ring 10 and the inner wall of the first mounting groove 211 of the upper plastic 20. Herein, the outer surface of the pressure ring 10 refers to the outer circumferential surface of the pressure ring 10. The inner wall of the first mounting groove 211 refers to the inner circumferential surface of the first mounting groove 211. The fourth air passage may include a gap T7. Specifically, the cross-sectional width of the pressure ring 10 in the thickness direction of the top cover assembly 100 is smaller than the cross-sectional width of the first mounting groove 211 in the thickness direction of the top cover assembly 100. Therefore, there is a gap between the outer circumferential surface of the pressure ring 10 and the inner circumferential surface of the first mounting groove 211, and this gap is the gap T7.

[0202] The gas detection passage S may further include a gap T8. The gap T8 is the gap between the inner surface of the second through hole 32 of the top cover 30 and the first convex portion 22 of the upper plastic 20.

[0203] It should be noted that in this embodiment, for the gas detection passage S provided in the top cover assembly 100, it is necessary to ensure that the first groove 12 of the pressure ring 10 and the second groove 33 of the top cover 30 are both open grooves. Among them, the open end of the first groove 12 faces away from the pole column 70. The open end of the second groove 33 faces the pole column 70.

[0204] It is understandable that the sealing ring 90 can improve the sealing effect of the battery. However, during the use of the battery, the terminal post 70 may heat up due to long-term use or other reasons. Since the sealing ring 90 is elastic, after receiving the heat from the terminal post 70, the sealing ring 90 will rebound and expand the terminal post 70 in the direction away from the top cover assembly 100. This causes the insufficient compression of the sealing ring 90, and further causes the sealing surface at the position of the terminal post 70 to fail, resulting in a liquid leakage phenomenon.

[0205] Therefore, in this embodiment, when the sealing surface fails, gases inside the battery, such as helium, argon, etc., enter through the gap between the inner peripheral surface of the fifth through-hole 821 of the lower plastic 80 and the outer peripheral surface of the terminal post base 72, and then enter the gap between the surface of the lower plastic 80 facing away from the top cover 30 and the surface of the terminal post base 72 close to the third sub-part 713, and then enter the gap between the sealing ring 90 and the fourth through-hole 811 of the lower plastic 80, and then diffuse to the failed sealing surface of the sealing ring 90, and then enter the gas detection channel S of the top cover assembly 100. At this time, the gas can have the following diffusion paths.

[0206] Exemplarily, as Figure 17 shown by the arrow path of, the gas diffuses to the open end of the second groove 33 of the top cover 30 through the gap T8 between the second through-hole 32 of the top cover 30 and the first convex part 22 of the upper plastic 20, and then diffuses to the gap T1 between the limiting body 40 and the bottom wall of the second groove 33 through the gap T2 between the limiting body 40 and the inner peripheral surface of the second groove 33. Then it diffuses upward around the limiting body 40, and continues to diffuse upward through the gaps T3 and T4 between the positioning hole 212 of the upper plastic 20 and the limiting body 40 to the open end of the first groove 12 of the pressing ring 10. Then it diffuses to the gap T7 between the outer peripheral surface of the pressing ring 10 and the inner peripheral surface of the first installation groove 211 through the open end of the first groove 12. Finally, it overflows to the outside of the battery and is detected by the detection device.

[0207] Exemplarily, as Figure 19 shown by the arrow path of, Figure 19 is a schematic diagram of a diffusion path of the gas inside the top cover assembly 100. The gas diffuses to the open end of the second groove 33 of the top cover 30 through the gap T8 between the second through-hole 32 of the top cover 30 and the first convex part 22 of the upper plastic 20. Then it diffuses upward around the limiting body 40, and continues to diffuse upward through the gaps T3 and T4 between the positioning hole 212 of the upper plastic 20 and the limiting body 40 to the gap T6 between the inner peripheral surface of the first groove 12 of the pressing ring 10 and the limiting body 40. Then it diffuses to the open end of the first groove 12 of the pressing ring 10 through the gap T5 between the limiting body 40 and the bottom wall of the first groove 12. Then it diffuses to the gap T7 between the outer peripheral surface of the pressing ring 10 and the inner peripheral surface of the first installation groove 211 through the open end of the first groove 12. Finally, it overflows to the outside of the battery and is detected by the detection device.

[0208] In the embodiments of the present application, by providing a gas detection channel S in the top cover assembly 100, gas leakage can be detected in a timely manner. This avoids the formation of a false seal on the contact surface between the upper plastic 20 and the top cover 30, and enables the true detection of the sealing performance of the sealing surface. Thereby, the use safety and service life of the battery are improved, and at the same time, the yield of the battery product is also enhanced.

[0209] In addition, in the embodiments of the present application, neither the surface of the pressing ring 10 close to the upper plastic 20 nor the surface of the top cover 30 close to the upper plastic 20 is provided with a radially penetrating groove or through hole. When the pressing ring 10 is placed on the pole column 70, this enables a relatively uniform extrusion force to be applied to the sealing ring 90, and makes the extrusion surface between the pressing ring 10 and the top cover 30 and the pole column 70 smoother, and the extrusion force more uniform, further enhancing the sealing performance of the annular sealing surface.

[0210] The embodiments of the present application have been introduced in detail above. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A top cover assembly, characterized in that, The top cover assembly includes a pole, a top cover, an upper plastic, a pressure ring and a limiter; The pole is connected to the top cover; The upper plastic sleeve is arranged on the pole, and along the radial direction of the pole, the upper plastic is located between the top cover and the pole, and the upper plastic includes an upper plastic body and a positioning hole, and the positioning hole is arranged on the upper plastic body and penetrates the upper plastic body along the thickness direction of the upper plastic; The pressure ring is sleeved on the pole and abuts against a side of the upper plastic body away from the top cover; and The limiting body passes through the positioning hole and is located between the pressure ring and the top cover in the thickness direction of the top cover. In the circumferential direction of the limiting body, part of the outer surface of the limiting body is interference connected with part of the inner surface of the positioning hole.

2. The top cover assembly according to claim 1, characterized in that The positioning hole includes a first side surface and a second side surface. Along the circumferential direction of the positioning hole, two ends of the first side surface are respectively connected to two ends of the second side surface, and the first side surface is bent and extended between the two ends of the second side surface. The outer surface of the limiting body is interference connected with part of the first side surface and part of the second side surface.

3. The top cover assembly according to claim 1, characterized in that The positioning hole is in an elliptical or irregular circular shape.

4. The top cover assembly according to claim 1, wherein The positioning hole includes at least three first side surfaces. Along the circumferential direction of the positioning hole, each of the first side surfaces are connected end to end to form the positioning hole. Along the circumferential direction of the positioning hole, a portion of the outer surface of the limiting body is interference connected with at least three of the first side surfaces.

5. The top cover assembly according to claim 1, characterized in that, The positioning hole includes two first side surfaces and two second side surfaces. Along the circumferential direction of the positioning hole, each first side surface is connected between two adjacent second side surfaces, and the outer surface of the limiting body is interference connected with the two first side surfaces and / or the two second side surfaces.

6. The top cover assembly according to claim 1, wherein The positioning hole comprises at least three first side surfaces and at least three second side surfaces, and along the circumferential direction of the positioning hole, each of the first side surfaces is connected between two adjacent second side surfaces, and the outer surface of the limiting body is interference-connected with at least three of the first side surfaces and / or at least three of the second side surfaces; A maximum distance between the first side surface and the central axis of the limiting body is different from a maximum distance between the second side surface and the central axis of the limiting body.

7. The top cover assembly according to any one of claims 2-6, characterized in that, The upper plastic body is provided with a first mounting groove, the opening of the first mounting groove is located on the surface of the upper plastic away from the top cover, the positioning hole passes through the bottom wall of the first mounting groove and the surface of the upper plastic body facing the top cover, and part of the pressure ring is located in the first mounting groove.

8. The top cover assembly according to claim 7, wherein The positioning hole comprises a first hole and a second hole sequentially arranged along the thickness direction of the upper plastic, the first hole comprises the first side surface and the second side surface, and the second hole is coaxially arranged with the first hole and is connected; The second hole is disposed on the bottom wall of the first mounting groove away from the opening of the first hole, and the maximum dimension of the second hole in the length direction of the upper plastic gradually decreases from the upper plastic toward the top cover; and / or, The opening of the second hole away from the first hole is arranged on the surface of the upper plastic facing the top cover, and the maximum dimension of the second hole in the length direction of the upper plastic gradually increases from the upper plastic toward the top cover.

9. The top cover assembly according to any one of claims 1-6, characterized in that, The maximum dimension of the limiting body in the length direction of the top cover assembly gradually decreases from the pressure ring toward the upper plastic.

10. The top cover assembly according to any one of claims 1-6, characterized in that, The melting point of the limiting body is greater than the melting point of the upper plastic.

11. The top cover assembly according to any one of claims 1-6, characterized in that, The pressing ring is provided with a first groove, and the opening of the first groove is located on the surface of the pressing ring facing the upper plastic; The top cover is provided with a second groove, and the opening of the second groove is located on the surface of the top cover facing the upper plastic; One end of the limiting body is located in the first groove, and the other end of the limiting body is located in the second groove.

12. The top cover assembly according to claim 11, wherein The pressing ring is provided with a first through hole, the first through hole penetrates the pressing ring along the thickness direction of the pressing ring, part of the pole is located in the first through hole, and the pressing ring is provided with a first notch, the first notch penetrates the outer side wall of the pressing ring in the radial direction, and connects the first groove and the outside of the pressing ring; The top cover is provided with a second through hole, which penetrates the top cover along the thickness direction of the top cover, and part of the pole is located in the second through hole. The top cover is provided with a second notch, which penetrates the inner wall of the second through hole and connects the second groove and the second through hole.

13. The top cover assembly according to claim 11, wherein, The shortest distance between the bottom wall of the first groove and the bottom wall of the second groove is greater than the height of the limiting body.

14. The top cover assembly according to claim 11, wherein The gap area between the outer surface of the limiting body and the inner wall of the second groove forms a first air channel, the gap area between the outer surface of the limiting body and the inner surface of the positioning hole forms a second air channel, the gap area between the outer surface of the limiting body and the inner wall of the first groove forms a third air channel, and the gap area between the outer surface of the pressure ring and the inner wall of the first mounting groove forms a fourth air channel. The first air channel, the second air channel, the third air channel and the fourth air channel are connected in sequence and form at least a partial gas detection channel of the top cover assembly.

15. The top cover assembly according to claim 12, wherein The top cover is further provided with a second mounting groove, the opening of the second mounting groove is located on the surface of the top cover facing the upper plastic, the second mounting groove is coaxially arranged and communicated with the second through hole, part of the upper plastic body is located in the second mounting groove, and the opening of the second groove is located on the bottom wall of the second mounting groove; The upper plastic also includes a first convex portion, the first convex portion is fixedly connected to a surface of the upper plastic body facing away from the pressure ring, and the first convex portion is located in the second through hole; The upper plastic is provided with a third through hole, the third through hole penetrates the upper plastic body and the first convex portion along the thickness direction of the upper plastic, the third through hole is coaxially arranged with and communicates with the first mounting groove, the third through hole is connected between the first through hole and the second through hole, and communicates with the first through hole and the second through hole; The pole includes a pole base and a pole body, wherein the pole base is located on the side of the top cover away from the pressure ring, one end of the pole body is fixedly connected to the pole base, the pole body passes through the first through hole, the second through hole and the third through hole, and the other end of the pole body extends out of the pressure ring.

16. The top cover assembly according to claim 15, characterized in that, The top cover assembly also includes a sealing ring, which is sleeved on the pole body, connected between the top cover and the pole base, and also connected between the first protrusion and the pole base.

17. The top cover assembly according to claim 15, characterized in that, The top cover assembly also includes a lower plastic, which is connected to a surface of the top cover facing away from the pressure ring, and a portion of the lower plastic is located between the top cover and the pole base.

18. A battery, characterized in that, The battery comprises a shell, a battery cell and a top cover assembly as described in any one of claims 1 to 17, wherein the top cover assembly is connected to the shell and encloses the shell to form a storage space for the battery, and the battery cell is located in the storage space.

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

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