Top cover assembly and battery

Abstract

The invention discloses a top cover assembly and a battery. The top cover assembly comprises a top cover, a welding ring, a glass ring and a pole. The top cover is provided with a first through hole. The welding ring is at least partially accommodated in the first through hole, and the welding ring is provided with a second through hole. The glass ring is contained in the second through hole and provided with a third through hole. The pole is accommodated in the third through hole, the glass ring is configured to seal a gap between the welding ring and the pole, and the welding ring is configured to seal a gap between the top cover and the glass ring. The welding ring can decouple the connection relation between the glass ring and the top cover, the welding ring serves as an independent middleware, the welding ring can be assembled with the glass ring and the pole firstly, then the whole welding ring is pressed into the first through hole and connected with the top cover, the assembling steps of the top cover assembly are simplified, and the connection efficiency is improved. In addition, compared with the mode that the top cover is directly connected with the glass ring, the size difference between the welding ring and the glass ring is small, the glass ring can be matched with the glass ring more easily, the connecting difficulty is small, and the assembling precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of battery manufacturing, and more particularly, to a top cover assembly and a battery. BACKGROUND

[0002] In the manufacturing process of the top cover assembly of the battery, when the sintering process of the glass ring is adopted, the glass ring, the pole and the top cover are put into the sintering furnace for integrated sintering. However, the size of the top cover is large, there is a size gap among the glass ring, the pole and the top cover, and the connection among the glass ring, the pole and the top cover is difficult, and the assembly precision is poor. SUMMARY

[0003] The present application provides a top cover assembly and a battery.

[0004] In a first aspect, the present application provides a top cover assembly. The top cover assembly comprises a top cover, a welding ring, a glass ring and a pole. The top cover is provided with a first through hole. The welding ring is at least partially accommodated in the first through hole, and the welding ring is provided with a second through hole. The glass ring is accommodated in the second through hole, and the glass ring is provided with a third through hole. The pole is accommodated in the third through hole, the glass ring is configured to seal the gap between the welding ring and the pole, and the welding ring is configured to seal the gap between the top cover and the glass ring.

[0005] In some embodiments, the welding ring, the glass ring and the pole are an integral structure, and the integral structure is connected with the top cover.

[0006] In some embodiments, the welding ring, the glass ring and the pole form an integral structure by sintering, and the integral structure is welded to the top cover.

[0007] In some embodiments, the welding ring comprises a first part and a second part. The first part is used to surround the second through hole. The second part is arranged on the outer side of the first part away from the second through hole and between the first part and the top cover.

[0008] In some embodiments, in the thickness direction of the top cover, the thickness of the first part is greater than the thickness of the second part.

[0009] In some embodiments, the thickness of the first part is greater than or equal to 1.8 mm and less than or equal to 3.5 mm.

[0010] In some embodiments, the thickness of the second part is greater than or equal to 1.5 mm and less than or equal to 3.5 mm.

[0011] In some embodiments, the upper surface of the first portion is flush with the upper surface of the glass ring in the thickness direction of the top cover.

[0012] In some embodiments, the upper surface of the second portion is flush with the upper surface of the top cover in the thickness direction of the top cover.

[0013] In some embodiments, the welding ring further comprises a third portion. The third portion is arranged on the inner side of the first portion close to the second through hole and cooperates with the first portion to enclose the second through hole. The glass ring is provided with a notch matched with the third portion, and the third portion cooperates with the notch to support the glass ring.

[0014] In some embodiments, the radial thickness of the glass ring is greater than or equal to 0.7 mm.

[0015] In some embodiments, the current I of the pole, the time t during which the pole is continuously powered, the resistivity p of the pole, the length L of the conductive path of the pole, the maximum heat Q_max allowed by the pole, the safety factor n, and the conductive cross-sectional area S of the pole satisfy: S ≥ (I² ρLn) / Q_max. The safety factor n is greater than or equal to 1.1 and less than or equal to 1.5.

[0016] In some embodiments, the welding ring is provided with a plurality of second through holes, the glass ring comprises a plurality of, the pole comprises a plurality of, and the plurality of poles, the plurality of glass rings, and the plurality of second through holes correspond respectively. Each glass ring is accommodated in a corresponding second through hole, and each pole is accommodated in a third through hole of a corresponding glass ring.

[0017] In a second aspect, the application provides a battery comprising the top cover assembly of any one of the above embodiments.

[0018] In the top cover assembly and the battery of the application, the welding ring can decouple the connection between the glass ring and the top cover. The welding ring, as an independent intermediate part, can be assembled with the glass ring and the pole first, and then pressed into the first through hole and connected with the top cover, thereby simplifying the assembly steps of the top cover assembly and improving the connection efficiency. In addition, compared with the mode in which the top cover is directly connected with the glass ring, the size difference between the welding ring and the glass ring is smaller, so that the glass ring is more easily matched with the glass ring, the connection difficulty is small, and the assembly precision is improved.

[0019] Additional aspects and advantages of the application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which: Figure 1 is a perspective assembly view of a battery according to some embodiments of the present application; Figure 2 is a perspective assembly view of a battery according to some embodiments of the present application; Figure 1 Figure 3 is a perspective assembly view of a battery according to some embodiments of the present application; Figure 2 Figure 4 is a perspective assembly view of a battery according to some embodiments of the present application; Figure 1 Figure 5 is a perspective assembly view of a battery according to some embodiments of the present application; Figure 4

[0021] Reference Signs: Battery 1000; top cover assembly 100; top cover 10; first through hole 11; upper surface 13; welding ring 30; second through hole 31; first portion 33; upper surface 331; second portion 35; upper surface 351; third portion 37; glass ring 50; third through hole 51; notch 53; upper surface 55; pole post 70; lower plastic 90. DETAILED DESCRIPTION

[0022] Embodiments of the present application are described in detail below with reference to the attached drawing figures, wherein the same or like reference numerals and characters are used throughout the figures to denote like components. As such, the embodiments described below are merely exemplary, and cannot be construed as limiting the present application.

[0023] In the description of the present application, it is to be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are merely for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be construed as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be construed as limiting the present application. In addition, features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more. ​​​​In the description of the present application, it should be noted that unless otherwise expressly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] The conventional battery top cover assembly includes a compression ring, an upper plastic, an aluminum sheet, a sealing ring, a lower plastic, and a pole. The pole is used to connect the external circuit and the battery internal cell. The lower plastic surrounds the pole and is located below the aluminum sheet, which is used for insulation and support to prevent the pole from directly contacting the aluminum sheet, causing a short circuit. The sealing ring is provided on the periphery of the lower plastic and is in close contact with the aluminum sheet. It fills the gap by elastic deformation, enhances the sealing performance, and prevents electrolyte leakage. The aluminum sheet serves as a base and is located in the middle, supporting various elements and having good electrical conductivity and thermal conductivity, which is beneficial to battery heat dissipation. The upper plastic is located above the aluminum sheet and surrounds the pole, insulating and supporting the compression ring, preventing the compression ring from directly contacting the aluminum sheet, and ensuring the insulation between the pole and the aluminum sheet. The compression ring is located at the top of the top cover assembly and surrounds the pole and is fixed by welding, etc., to ensure the integrity and sealing of the top cover assembly.

[0025] With the development of lithium batteries, the charging and discharging rate of the battery internal cell is getting higher and higher, and the heat generated in a short time is also getting larger and larger, which challenges some traditional materials for making batteries. For example, when performing a short circuit test, the temperature of the pole is often too high, causing the upper plastic to melt first, resulting in insulation and air tightness failure, and causing the cell to malfunction. Based on this, during the manufacturing process of the battery top cover assembly, a glass ring can be used. The glass ring is located between the pole and the top cover and has insulation and sealing functions, replacing the upper plastic, the sealing ring, and the compression ring. When using the sintering process of the glass ring, the glass ring, the pole, and the top cover are placed in the sintering furnace for integrated sintering. However, the size of the top cover is relatively large, while the size of the glass ring and the pole is relatively small, and there is a significant size difference between the three, which causes uneven heat distribution during sintering, affecting the sintering efficiency. That is, the size difference between the top cover and the glass ring and the pole makes it difficult to connect the three, and the connection efficiency is low.

[0026] Please refer to Figure 1 , and Figure 2 or Figure 4The top cover assembly 100 comprises a top cover 10, a welding ring 30, a glass ring 50 and a pole 70. The top cover 10 is provided with a first through hole 11. The welding ring 30 is at least partially accommodated in the first through hole 11, and the welding ring 30 is provided with a second through hole 31. The glass ring 50 is accommodated in the second through hole 31, and the glass ring 50 is provided with a third through hole 51. The pole 70 is accommodated in the third through hole 51, and the glass ring 50 is configured to seal the gap between the welding ring 30 and the pole 70, and the welding ring 30 is configured to seal the gap between the top cover 10 and the glass ring 50.

[0027] Specifically, the top cover 10, i.e. an aluminum sheet, is provided with a first through hole 11 penetrating in the thickness direction Z, and the first through hole 11 is used to accommodate the welding ring 30. The lower surface of the top cover 10 in the thickness direction Z is provided with a lower plastic 90 for insulating the top cover 10 and the conductive elements inside the battery 1000. The welding ring 30 is at least partially accommodated in the first through hole 11 and is provided with a second through hole 31, and the second through hole 31 is used to accommodate the glass ring 50. The welding ring 30 can seal the gap between the inner side wall of the first through hole 11 and the outer side wall of the glass ring 50, preventing the electrolyte of the battery 1000 from overflowing from the gap between the inner side wall of the first through hole 11 and the outer side wall of the glass ring 50. The glass ring 50 is accommodated in the second through hole 31 and is provided with a third through hole 51, and the third through hole 51 is used to accommodate the pole 70. The glass ring 50 can seal the gap between the inner side wall of the second through hole 31 and the outer side wall of the pole 70 ring, preventing the electrolyte of the battery 1000 from overflowing from the gap between the inner side wall of the second through hole 31 and the outer side wall of the pole 70 ring. In addition, the glass ring 50 is made of glass material, and the glass ring 50 is resistant to high temperature and insulating, so the glass ring 50 also has an insulating function, which can insulate the current between the pole 70 and the welding ring 30, and between the pole 70 and the top cover 10. The welding ring 30, the glass ring 50 and the pole 70 can be one or more, which is not limited here. In the plane perpendicular to the thickness direction Z, the cross sections of the first through hole 11, the second through hole 31 and the third through hole 51 can be circular, square or other shapes, which is not limited here. Exemplarily, the cross sections of the first through hole 11, the second through hole 31 and the third through hole 51 of the present application are circular, and the circular shape has no sharp corners, which can reduce stress concentration. It can be understood that the centers of the first through hole 11, the second through hole 31 and the third through hole 51 are located on the same axis, and the axis is parallel to the thickness direction Z of the top cover 10. Correspondingly, the pole 70, the welding ring 30 and the glass ring 50 are coaxial, which can reduce the assembly difficulty of the top cover assembly 100.

[0028] It can be understood that the connection mode of the welding ring 30 and the glass ring 50 and the connection mode of the welding ring 30 and the top cover 10 can be different, so that the welding ring 30 can be connected by selecting a connection mode more suitable for the glass ring 50 and a connection mode more suitable for the top cover 10, respectively, to improve the connection strength between the glass ring 50 and the welding ring 30 and between the top cover 10 and the welding ring 30. Exemplarily, the welding ring 30, the glass ring 50 and the pole 70 are connected by sintering, and the top cover 10 and the welding ring 30 are connected by welding In the top cover assembly 100 of the present application, the welding ring 30 can decouple the connection relationship between the glass ring 50 and the top cover 10. The welding ring 30 serves as an independent intermediate part. The welding ring 30 can be assembled with the glass ring 50 and the pole 70 first, and then integrally pressed into the first through hole 11 and connected with the top cover 10. This simplifies the assembly steps of the top cover assembly 100 and improves the connection efficiency. In addition, compared with the mode in which the top cover is directly connected with the glass ring, the size difference between the welding ring 30 and the glass ring 50 is smaller, so that the glass ring 50 is more easily matched with the glass ring 50, the connection difficulty is small, and the assembly precision is improved.

[0029] Please refer to Figure 2 or Figure 4 In some embodiments, the welding ring 30, the glass ring 50 and the pole 70 are an integrated structure, and the integrated structure is connected with the top cover 10.

[0030] Specifically, the welding ring 30, the glass ring 50 and the pole 70 have a small volume, and the top cover 10 has a relatively large size. After the elements with a small volume are formed into an integrated structure, the integrated structure is connected with the top cover 10, which simplifies the assembly process and improves the production efficiency Please refer to Figure 2 or Figure 4 In some embodiments, the welding ring 30, the glass ring 50 and the pole 70 are an integrated structure formed by sintering, and the integrated structure is welded with the top cover 10.

[0031] Specifically, the welding ring 30, the glass ring 50 and the pole 70 have a small volume, and the elements with a small volume have a relatively large surface-to-volume ratio, which can be heated more uniformly in the sintering process, thereby improving the sintering quality and shortening the sintering time compared with the sintering mode between the top cover 10 and the glass ring 50 and the pole 70. The integrated structure is welded with the top cover 10, the welding speed is fast, the process of secondary heating of the integrated structure can be reduced, and the connection strength is improved.

[0032] Please refer to Figure 3 or Figure 5In some embodiments, the welding ring 30 includes a first portion 33 and a second portion 35. The first portion 33 is configured to surround the second through hole 31. The second portion 35 is configured to surround the outside of the first portion 33 away from the second through hole 31 and is located between the first portion 33 and the top cover 10. In the thickness direction Z of the top cover 10, the thickness L1 of the first portion 33 is greater than the thickness L2 of the second portion 35.

[0033] Specifically, the first portion 33 is located between the second portion 35 and the pole 70 and is configured to connect the welding ring 30 and the glass ring 50. The second portion 35 is located between the first portion 33 and the top cover 10 and is configured to connect the welding ring 30 and the top cover 10. In some embodiments, the first portion 33 and the second portion 35 are an integral structure, i.e., the first portion 33 and the second portion 35 are an integral structure, thereby improving the bonding strength between the first portion 33 and the second portion 35, preventing the first portion 33 and the second portion 35 from separating during the operation of the welding ring 30, and thereby ensuring the stability and reliability of the welding ring 30. In other embodiments, the first portion 33 and the second portion 35 are a split structure, i.e., the first portion 33 and the second portion 35 are two different structures. The present application illustrates the first portion 33 and the second portion 35 as an integral structure.

[0034] The first portion 33 is sintered to the glass ring 50. During sintering, the bonding site of the glass ring 50 and the welding ring 30 is subjected to thermal shock and stress. The first portion 33 has a large thickness, which can increase the area of the bonding site of the first portion 33 and the glass ring 50, disperse the stress generated during sintering, prevent the glass ring 50 from breaking or generating micro-cracks due to local stress concentration, and thereby improve the connection reliability and service life of the welding ring 30 and the glass ring 50. In addition, the thicker first portion 33 can also enhance the structural strength of the welding ring 30, ensuring that the bonding site of the welding ring 30 and the glass ring 50 will not deform or be damaged during the use of the battery 1000. The second portion 35 has a small thickness, which can reduce the use of materials and reduce the weight of the welding ring 30.

[0035] Please refer to Figure 3 or Figure 5 In some embodiments, the thickness L1 of the first portion 33 is greater than or equal to 1.8 mm and less than or equal to 3.5 mm.

[0036] Specifically, the thickness L1 of the first portion 33 can be 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.4 mm, or 3.5 mm. If the thickness L1 of the first portion 33 is less than 1.8 mm, the first portion 33 is too thin, resulting in insufficient structural strength of the first portion 33, and deformation or damage can easily occur at the joint between the first portion 33 and the glass ring 50 during use of the battery 1000, affecting the air tightness of the top cover assembly 100. If the thickness L1 of the first portion 33 is greater than 3.5 mm, the amount of material used for the first portion 33 will increase, increasing the weight of the top cover assembly 100.

[0037] The thickness L1 of the first portion 33 is greater than or equal to 1.8 mm and less than or equal to 3.5 mm, which can ensure the connection strength between the first portion 33 and the glass ring 50 while avoiding excessive use of materials, ensuring the reliability and air tightness of the battery 1000 sealing, and controlling the weight of the top cover assembly 100.

[0038] Referring to Figure 3 or Figure 5 In some embodiments, the thickness L2 of the second portion 35 is greater than or equal to 1.5 mm and less than or equal to 3.5 mm.

[0039] Specifically, the thickness L2 of the second portion 35 can be 1.5 mm, 1.8 mm, 2.1 mm, 2.2 mm, 2.5 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.4 mm, or 3.5 mm. If the thickness L2 of the second portion 35 is less than 1.5 mm, the second portion 35 is too thin, resulting in insufficient structural strength of the second portion 35, and deformation or damage can easily occur at the joint between the second portion 35 and the top cover 10, affecting the air tightness of the top cover assembly 100. If the thickness L2 of the second portion 35 is greater than 3.5 mm, the amount of material used for the first portion 33 will increase, increasing the weight of the top cover assembly 100.

[0040] The thickness L2 of the second portion 35 is greater than or equal to 1.5 mm and less than or equal to 3.5 mm, which can ensure the connection strength between the second portion 35 and the top cover 10 while avoiding excessive use of materials, ensuring the reliability and air tightness of the battery 1000 sealing, and controlling the weight of the top cover assembly 100.

[0041] Referring to Figure 3 or Figure 5 In some embodiments, in the thickness direction Z of the top cover 10, the upper surface 331 of the first portion 33 is flush with the upper surface 55 of the glass ring 50.

[0042] Specifically, the upper surface 331 of the first portion 33 is flush with the upper surface 55 of the glass ring 50, so that a flat transition surface is formed between the first portion 33 of the welding ring 30 and the glass ring 50. The flat transition surface helps to more evenly distribute stress, reducing the risk of the glass ring 50 breaking due to uneven stress during use. At the same time, the upper surface 331 of the first portion 33 being flush with the upper surface 55 of the glass ring 50 also simplifies the assembly step during production, reduces the need for adjustment of the relative positions of the welding ring 30 and the glass ring 50, and improves production efficiency.

[0043] Referring to Figure 3 or Figure 5 In some embodiments, the upper surface 351 of the second portion 35 is flush with the upper surface 13 of the top cover 10 in the thickness direction Z of the top cover 10.

[0044] Specifically, the upper surface 351 of the second portion 35 is flush with the upper surface 13 of the top cover 10, so that a flat transition surface is formed between the second portion 35 of the welding ring 30 and the top cover 10, facilitating assembly and connection with other components, and also helping to improve the overall aesthetics of the battery 1000.

[0045] Referring to Figure 3 In some embodiments, the welding ring 30 further comprises a third portion 37. The third portion 37 is arranged around the inner side of the first portion 33 near the second through hole 31 and cooperates with the first portion 33 to enclose the second through hole 31. The glass ring 50 is provided with a notch 53 that cooperates with the third portion 37, and the third portion 37 cooperates with the notch 53 to support the glass ring 50.

[0046] Specifically, the third portion 37 cooperates with the notch 53 to support the glass ring 50. The third portion 37 provides support for the glass ring 50, helping to maintain the stability of the glass ring 50 during sintering, preventing displacement of the glass ring 50 under gravity or external vibration at high temperatures, and ensuring the sealing and airtightness between the glass ring 50 and the welding ring 30. In addition, the cooperation of the third portion 37 and the notch 53 of the glass ring 50 can also enhance the installation stability of the glass ring 50, avoiding loosening or displacement of the glass ring 50 due to mechanical stress during use, further improving the reliability and durability of the top cover assembly 100. In one example, the third portion 37 is a plurality of, which can be point-like protrusions, etc., and is not limited herein. The plurality of third portions 37 are arranged around the inner side of the first portion 33 near the second through hole 31. In another example, the third portion 37 is a ring-shaped protrusion, which is conducive to the molding of the third portion 37. Correspondingly, the notch 53 of the glass ring 50 is a ring-shaped groove, and the ring-shaped protrusion and the ring-shaped groove are connected by clamping, which can increase the connection area of the third portion 37 and the glass ring 50, and improve the support of the third portion 37 for the glass ring 50.

[0047] Referring to Figure 3or Figure 5 In some embodiments, the radial thickness L3 of the glass ring 50 is greater than or equal to 0.7 mm.

[0048] Specifically, the glass ring 50, although being an insulating material, needs to have a certain radial X thickness to play an insulating role. In the radial X direction, the radial thickness L3 of the glass ring 50 can be 0.7 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.5 mm, or 3.0 mm. If the radial thickness L3 of the glass ring 50 is less than 0.7 mm, the glass ring 50 cannot meet the insulating voltage withstand requirement and is prone to creepage breakdown. Although the welding ring 30 and the pole 70 have a certain insulating distance in the radial X direction (i.e., the radial X thickness of the glass ring 50), an arc path is generated, causing creepage breakdown. If the radial X thickness of the glass ring 50 is greater than 3.0 mm, the structural strength of the top cover assembly 100 is reduced.

[0049] The radial thickness L3 of the glass ring 50 is greater than or equal to 0.7 mm and less than or equal to 3.0 mm, which can not only ensure that the glass ring 50 resists arc breakdown during use of the battery 1000 and maintains insulating performance, but also ensure the structural strength of the top cover assembly 100.

[0050] Please refer to Figure 1 , and Figure 2 or Figure 4 In some embodiments, the continuous current I of the pole 70, the time t during which the pole 70 is continuously powered, the resistivity p of the pole 70, the length L of the conductive path of the pole 70, the maximum heat quantity Q_max allowed by the pole 70, the safety factor n, and the conductive cross-sectional area S of the pole 70 satisfy: S ≥ (I² ρLn) / Q_max. The safety factor n is greater than or equal to 1.1 and less than or equal to 1.5.

[0051] Specifically, it can be understood that the size of the pole 70 needs to meet the overcurrent temperature rise requirement of the battery 1000, i.e., according to the Joule law: Q=I 2 Rt, and the resistance formula: R=ρL / S, it can be known that the conductive cross-sectional area S of the pole 70 satisfies: S ≥ (I² ρLn) / Q_max In the formula, the continuous current I of the pole post 70 is the current size through the pole post 70 in the case of the battery 1000 being powered on, the time t of the pole post 70 being continuously powered on is the time of the battery 1000 being powered on in the case of the battery 1000 being powered on, the resistivity p of the pole post 70 is determined by the material constituting the pole post 70, the conductive cross-sectional area S of the pole post 70 is the cross-sectional area of the pole post 70 being cut by a plane parallel to the top cover 10, and the conductive path length L of the pole post 70 is the length of the current flowing through the pole post 70, that is, the distance from the top of the pole post 70 to the bottom of the pole post 70. The maximum heat generation Q_max allowed by the pole post 70 is proportional to the resistance R of the pole post 70, and the resistance R of the pole post 70 is inversely proportional to the conductive cross-sectional area S of the pole post 70. Therefore, the maximum heat generation Q_max allowed by the pole post 70 is inversely proportional to the conductive cross-sectional area S of the pole post 70, and when the conductive cross-sectional area S of the pole post 70 is greater than a certain value, the maximum heat generation Q_max allowed by the pole post 70 can only be kept less than a value, otherwise, when the conductive cross-sectional area S of the pole post 70 is too small, the maximum heat generation Q_max allowed by the pole post 70 is too large, which can cause the pole post 70 to have a too high temperature rise, and can cause the pole post 70 to be broken, catch fire, and the like.

[0052] In addition, a safety factor n should also be reserved for appropriately expanding the size of the pole post 70. The safety factor n can be 1.1, 1.15, 1.21, 1.26, 1.31, 1.35, 1.41, 1.43, 1.48, or 1.5. If the safety factor n is less than 1.1, the pole post 70 can not be able to cover the dimensional error generated when the pole post 70 is made, and the conductive cross-sectional area S of part of the pole post 70 can be lower than the above requirement (S≥ (I²pLn) / Q_max), which can cause the pole post 70 to have a risk of being broken and catching fire; if the safety factor n is greater than 1.5, the conductive cross-sectional area S of the pole post 70 can be excessively increased, which can increase the material cost and volume of the pole post 70.

[0053] The safety factor n being greater than or equal to 1.1 and less than or equal to 1.5 can ensure that the conductive cross-sectional area S of the pole post 70 actually produced is S≥ (I²pLn) / Q_max, and can also control the material cost and volume of the pole post 70.

[0054] Please refer to Figure 4 and Figure 5 In some embodiments, the welding ring 30 is provided with a plurality of second through holes 31, the glass ring 50 includes a plurality of, the pole post 70 includes a plurality of, the plurality of pole posts 70, the plurality of glass rings 50, and the plurality of second through holes 31 correspond respectively, each glass ring 50 is accommodated in the corresponding second through hole 31, and each pole post 70 is accommodated in the third through hole 51 of the corresponding glass ring 50.

[0055] Specifically, the pole post 70 includes a plurality of fingers for the pole post 70 of the same polarity, i.e., the pole post 70 of the application includes a plurality of fingers, the pole post 70 of the positive electrode of the top cover assembly 100 includes a plurality of fingers, and / or the pole post 70 of the negative electrode of the top cover assembly 100 includes a plurality of fingers. Exemplarily, Figure 4 and Figure 5 Among them, there are 8 pole posts 70, which are 4 positive pole posts 70 and 4 positive pole posts 70 respectively. In other embodiments of the application, the pole posts 70 can be other quantities. In the embodiment in which the top cover assembly 100 includes four pole posts 70 of the same polarity, it also includes four glass rings 50 and four second through holes 31 respectively, and each pole post 70 corresponds to a glass ring 50 and a second through hole 31. The distribution of the pole posts 70 is usually uniform to ensure the structural stability of the top cover assembly 100.

[0056] During the sintering process, the plurality of pole posts 70 and the glass rings 50 can be sintered at the same time to improve production efficiency. Since each glass ring 50 only needs to correspond to one pole post 70, compared with the design of a single glass ring 50 corresponding to multiple pole posts 70, the size of each glass ring 50 can be smaller, and the heat distribution during sintering can be more easily controlled, making the combination of the glass ring 50 and the welding ring 30 and the pole post 70 more uniform and compact, reducing the problem of uneven sintering and stress concentration caused by the glass ring 50 being too large, and improving the sintering quality. After the battery 1000 is manufactured, the design of multiple pole posts 70 and multiple glass rings 50 can disperse the current, reduce the current density of a single pole post 70, reduce heating, and improve the overcurrent capacity and safety of the battery 1000. At the same time, multiple glass rings 50 provide multiple seals, enhance the air tightness of the top cover assembly 100, reduce the risk of internal electrolyte leakage of the battery 1000, and prolong the service life of the battery 1000. In addition, the symmetrical and uniform distribution of the pole posts 70 helps to optimize the current distribution inside the battery 1000, improving the overall performance and consistency of the battery 1000.

[0057] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0058] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely divergences of the principles and application of the present application and that numerous modifications, changes, substitutions, and alterations can be made thereto without departing from the spirit and scope of the present application, which is defined by the following claims and their equivalents.

Claims

1. A top cover assembly, characterized in that, include: The top cover has a first through hole; A welding ring, at least partially accommodated in the first through hole, and the welding ring is provided with a second through hole; A glass ring, accommodated in the second through hole, the glass ring having a third through hole; and An electrode post is received in the third through hole, and the glass ring is configured to seal the gap between the welding ring and the electrode post, and the welding ring is configured to seal the gap between the top cover and the glass ring.

2. The top cover assembly according to claim 1, characterized in that, The welding ring, the glass ring, and the pole are an integral structure, and the integral structure is connected to the top cover.

3. The top cover assembly according to claim 2, characterized in that, The welding ring, the glass ring, and the pole are formed into an integral structure by sintering, and the integral structure is welded to the top cover.

4. The top cover assembly according to claim 1, characterized in that, The welding ring includes: The first part is used to surround and form the second through hole; and The second part is disposed around the outside of the first part opposite to the second through hole, and is located between the first part and the top cover.

5. The top cover assembly according to claim 4, characterized in that, In the thickness direction of the top cover, the thickness of the first part is greater than the thickness of the second part.

6. The top cover assembly according to claim 4, characterized in that, The thickness of the first part is greater than or equal to 1.8 mm and less than or equal to 3.5 mm; and / or, The thickness of the second part is greater than or equal to 1.5 mm and less than or equal to 3.5 mm.

7. The top cover assembly according to claim 4, characterized in that, In the thickness direction of the top cover, the upper surface of the first part is flush with the upper surface of the glass ring; and / or, In the thickness direction of the top cover, the upper surface of the second part is flush with the upper surface of the top cover.

8. The top cover assembly according to claim 4, characterized in that, The welding ring also includes: The third part is arranged around the inner side of the first part near the second through hole, and together with the first part, forms the second through hole. The glass ring has a notch that mates with the third part, and the third part mates with the notch to support the glass ring.

9. The top cover assembly according to claim 1, characterized in that, The radial thickness of the glass ring is greater than or equal to 0.7 mm.

10. The top cover assembly according to claim 1, characterized in that, The continuous current I of the electrode, the continuous energizing time t of the electrode; the resistivity ρ of the electrode, the conductive path length L of the electrode, the maximum allowable heat generation Q_max of the electrode, the safety factor n, and the conductive cross-sectional area S of the electrode satisfy the following: S ≥ (I²ρLn) / Q_max The safety factor n is greater than or equal to 1.1 and less than or equal to 1.

5.

11. The top cover assembly according to any one of claims 1-10, characterized in that, The welding ring is provided with a plurality of second through holes, the glass ring includes a plurality of components, the pole includes a plurality of components, the plurality of poles, the plurality of glass rings and the plurality of second through holes are respectively corresponding, each glass ring is accommodated in the corresponding second through hole, and each pole is accommodated in the corresponding third through hole of the glass ring.

12. A battery, characterized in that, The battery includes the top cover assembly as described in any one of claims 1-11.

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