Top cover assembly and battery

Abstract

The utility model discloses a top cover assembly and battery, top cover assembly includes top cover, pole, compression ring and sealant, and top cover is provided with inner hole, and pole is worn and is equipped with inner hole, and pole has the first end and second end of opposite settings, and compression ring is connected with the first end of pole, and compression ring includes first pressure part and second pressure part, and second pressure part sets up at the side of first pressure part to top cover, and the width of second pressure part is less than the width of first pressure part, and sealant includes the first seal part and second seal part of interconnection, and first seal part is pressed and sets up between first pressure part and top cover, and second seal part is pressed and sets up between second pressure part and top cover. Through this technical scheme, through the optimization compression ring structure and the partition sealing, realized the reasonable distribution of sealant compression ratio, not only solved the sealant easy to rise, the expansion and the overflow glue etc. of prior art, also promoted the sealing performance and structural stability of assembly, realized safe, reliable and size controlled top cover assembly.

Description

Technical Field

[0001] This utility model relates to the technical field of top cover components, and more particularly to top cover components and power systems. Background Technology

[0002] With the increasing popularity of large-screen smartphones and tablets, user demand for compatible input devices—especially screen styluses—continues to grow. At the same time, mobile devices are becoming increasingly thinner and lighter, placing higher demands on the portability and integration of styluses. To adapt to this trend, the diameter of styluses also needs to be further reduced for easier storage and carrying, thus improving the user experience.

[0003] In recent years, thanks to advancements in rechargeable lithium-ion battery technology, styluses have expanded beyond basic screen writing and touch functions to integrate more intelligent features, such as remote control operation, gesture recognition, AI input, and health monitoring. These innovative features have greatly enriched the application scenarios of electronic products, placing more stringent demands on the size, capacity density, and electrical performance of the batteries inside styluses. Achieving high energy density, high safety, and structural reliability within a limited space has become one of the key technological challenges in this field.

[0004] Currently, most styluses on the market use pouch batteries as their power source. While pouch batteries offer some flexibility, they also have several drawbacks. First, due to limitations in the side-sealing and folding process, pouch batteries cannot be miniaturized to a diameter of less than 5mm, failing to meet the assembly requirements of next-generation ultra-fine styluses. Second, the pouch structure results in poor battery dimensional stability, and its complex structure makes detachable designs difficult, leading to inconvenient maintenance and replacement. Furthermore, pouch batteries are prone to bulging and explosions in practical applications, posing safety hazards and exhibiting low reliability. Due to these factors, there are currently few mobile phone styluses on the market equipped with built-in lithium batteries. Some products have switched to using electronic capacitors as their power source, but the energy density of electronic capacitors is far lower than that of lithium-ion batteries, only one-tenth or even less, severely limiting the expansion of stylus functionality and usage time.

[0005] To address the limitations of pouch batteries, the industry has begun exploring the use of hard-shell batteries in styluses. Hard-shell batteries offer advantages such as dimensional stability, simple structure, high energy density, good safety and reliability, and ease of disassembly, making them theoretically more suitable for small styluses. However, the sealing and insulation technology of the battery cover assembly has become a bottleneck for the development of pin-type hard-shell batteries due to size constraints. Currently, the mainstream cover assembly sealing technologies include riveting seals, heat sealing, and roller groove seals. Heat sealing is difficult to achieve an effective bonding area in small-sized pin-type batteries, resulting in poor sealing performance; roller groove seals occupy a large height space, which is also difficult to meet miniaturization requirements; while riveting seals are suitable for a certain size range, the insulating adhesive is prone to overflow, affecting the overall dimensional accuracy of the battery and posing risks to product consistency and safety.

[0006] Therefore, developing a battery structure for styluses that combines high energy density, structural stability, safety and reliability with excellent sealing performance under size constraints has become a key technical problem that urgently needs to be solved in the current field. Utility Model Content

[0007] To achieve the above objectives, the present invention provides a top cover assembly: the top cover assembly includes a top cover, an electrode post, a pressure ring, and sealant; the top cover has an inner hole; the electrode post passes through the inner hole and has a first end and a second end disposed opposite to each other; the pressure ring is connected to the first end of the electrode post, and the pressure ring includes a first pressure portion and a second pressure portion, the second pressure portion being disposed on the side of the first pressure portion facing the top cover, and the width of the second pressure portion being smaller than the width of the first pressure portion; the sealant includes a first dense portion and a second dense portion connected to each other, the first dense portion being pressed between the first pressure portion and the top cover, and the second dense portion being pressed between the second pressure portion and the top cover.

[0008] Optionally, the thickness of the first pressing part is T1, the thickness of the second pressing part is T2, the thickness of the second pressing part is T3, and 0.1*T3<T2.

[0009] Optionally, the pressure ring further includes a third pressure part, which is disposed on the side of the second pressure part facing the top cover. The width of the third pressure part is smaller than the width of the second pressure part. The first pressure part, the second pressure part, and the third pressure part are in contact with the outer peripheral surface of the pole post, respectively.

[0010] Optionally, the inner hole includes a first hole and a second hole, the second hole being located between the first hole and the pressure ring, and the diameter D1 of the first hole being smaller than the diameter D2 of the second hole; the sealant also includes a third sealing portion, which is connected to the second sealing portion and located between the pole post and the wall of the inner hole.

[0011] Optionally, a chamfer is provided at the connection between the first hole and the second hole.

[0012] Optionally, the sealant also includes a third and a fourth sealed portion, the third sealed portion being connected to the second sealed portion and located between the pole post and the bore wall of the inner hole, and the fourth sealed portion being connected to the third sealed portion and located between the second end and the top cover.

[0013] Optionally, a protruding ring is provided on the side of the second end facing the top cover, and the protruding ring further presses against the fourth part.

[0014] The present invention also includes a battery, which includes a housing, a core pack, and a top cover assembly as described above. The housing has a receiving cavity and an opening communicating with the receiving cavity. The core pack is disposed in the receiving cavity. The top cover assembly is connected to the housing and seals the opening.

[0015] Optionally, the top cover includes a first cover portion and a second cover portion connected to each other. The first cover portion is located between the core package and the second cover portion. The diameter D3 of the first cover portion is smaller than the diameter D4 of the second cover portion. The first cover portion is spaced apart from the inner wall of the housing, and the second cover portion is in contact with the inner wall of the housing.

[0016] Optionally, the wall thickness of the shell is T4, where 0.1*T4 < (D4-D3).

[0017] Optionally, the top cover includes a third cover portion connected to the side of the second cover portion away from the first cover portion, the diameter D5 of the third cover portion being larger than the diameter D4 of the second cover portion, and the third cover portion overlapping the top surface of the housing.

[0018] The beneficial effects of this utility model are as follows: After applying this technical solution, the top cover assembly exhibits excellent sealing performance and structural reliability. Firstly, the stepped structure design of the pressure ring allows the sealant to be fully compressed in the second pressure section, forming the main sealing area, significantly improving the sealing effect of the assembly, effectively preventing gas and liquid leakage, and ensuring the safety of the internal environment of the battery cell. Secondly, the auxiliary compression and constraint of the sealant by the first pressure section significantly suppresses problems such as warping and radial expansion of the sealant when subjected to large compression in the main sealing area, maintaining the stability of the sealant's shape and position, and further improving the reliability of the seal. Furthermore, the presence of the first pressure section effectively limits the radial expansion and overflow of the sealant, ensuring that the size of the compressed sealant is controllable, preventing the overall dimensional deviation of the cover assembly and battery cell due to overflow, thereby ensuring assembly consistency and interchangeability. In summary, this technical solution achieves a reasonable distribution of sealant compression ratio by optimizing the pressure ring structure and partitioned sealing. This not only solves the problems of sealant lifting, expansion and overflow in the existing technology, but also improves the sealing performance and structural stability of the component, realizing a safe, reliable and dimensionally controlled top cover component. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the battery structure provided in an embodiment of the present invention;

[0021] Figure 2 This is provided by the embodiment of the present utility model. Figure 1 A magnified view of a portion of region A in the middle;

[0022] Figure 3 This is a schematic diagram of the reference numerals for a top cover assembly provided in one embodiment of the present utility model;

[0023] Figure 4 This is a schematic diagram of the dimensions of a top cover assembly provided in one embodiment of the present invention.

[0024] Explanation of icon numbers:

[0025] Housing 30, receiving cavity 31, opening 32, core package 20, top cover assembly 10, top cover 12, inner hole 124;

[0026] First hole 125, second hole 126, chamfer 127, first cover 121, second cover 122;

[0027] Third cover 123, pole post 14, first end 141, second end 142, protruding ring 143, pressure ring 16;

[0028] First pressing part 161, second pressing part 162, third pressing part 163, sealant 18, first sealing part 181; second sealing part 182, third sealing part 183, fourth sealing part 184. Detailed Implementation

[0029] The embodiments of this utility model will be described in detail below with reference to the accompanying drawings, clearly and comprehensively demonstrating the technical solution. It should be noted that the listed embodiments are only a part of this utility model, and not all possible implementations. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0030] Please see Figures 1 to 3 As shown, Figure 1 This is a schematic diagram of the battery structure provided in an embodiment of the present invention. Figure 2 This is provided by the embodiment of the present utility model. Figure 1 A magnified view of a portion of region A in the middle. Figure 3 This is a schematic diagram of the reference numerals for the top cover assembly 10 provided in one embodiment of the present invention. Figure 4 This is a schematic diagram of the dimensions of the top cover assembly 10 provided in one embodiment of the present invention.

[0031] This application protects a battery, which includes a housing 30, a core pack 20 and a top cover assembly 10. The housing 30 has a receiving cavity 31 and an opening 32 communicating with the receiving cavity 31. The core pack 20 is installed in the receiving cavity 31. The top cover assembly 10 is connected to the housing 30 and covers the opening 32.

[0032] This embodiment discloses a top cover assembly 10, including a top cover 12, an electrode post 14, a pressure ring 16, and a sealant 18. Specifically, the top cover 12 has an inner hole 124, and the electrode post 14 passes through the inner hole 124. The electrode post 14 has a first end 141 and a second end 142 disposed opposite to each other. The pressure ring 16 is connected to the first end 141 of the electrode post 14 and includes a first pressure portion 161 and a second pressure portion 162. The second pressure portion 162 is disposed on the side of the first pressure portion 161 facing the top cover 12, and the width of the second pressure portion 162 is smaller than the width of the first pressure portion 161, forming an inwardly concave step structure between the second pressure portion 162 and the first pressure portion 161. The sealant 18 includes a first sealing portion 181 and a second sealing portion 182 that are connected to each other. The first sealing portion 181 is pressed between the first pressure portion 161 and the top cover 12, and the second sealing portion 182 is pressed between the second pressure portion 162 and the top cover 12. The core of the top cover assembly 10 lies in the pressure ring 16, which employs at least one stepped structure, meaning it has at least two parts with different thicknesses. The second pressure section 162 primarily serves a sealing function, applying a large compression ratio to the sealant 18 to achieve the main seal and ensure the assembly's sealing performance and structural reliability. The first pressure section 161 acts as an auxiliary area, applying a smaller compression ratio to the sealant 18, thus constraining it and preventing it from warping or over-expanding when subjected to high compression in the second pressure section 162. Because the compression of the first pressure section 161 is relatively small, the expansion of the sealant 18 is limited, which helps control the diameter of the sealant 18 after compression, preventing it from overflowing from the top cover assembly 10 due to over-compression and affecting the overall diameter of the cover assembly or even the cell assembly dimensions.

[0033] After applying this technical solution, the top cover assembly 10 exhibits excellent sealing performance and structural reliability. Firstly, the stepped structure design of the pressure ring 16 allows the sealant 18 to be fully compressed in the second pressure section 162, forming the main sealing area and significantly improving the sealing effect of the assembly. This effectively prevents gas and liquid leakage, ensuring the safety of the internal environment of the battery cell. Secondly, the auxiliary compression and constraint of the sealant 18 by the first pressure section 161 significantly suppresses problems such as warping and radial expansion of the sealant 18 when subjected to large compression in the main sealing area, maintaining the stability of the shape and position of the sealant 18 and further improving the reliability of the seal. Furthermore, the presence of the first pressure section 161 effectively limits the radial expansion and overflow of the sealant 18, ensuring that the dimensions of the compressed sealant 18 are controllable and preventing the overall dimensions of the cover assembly and battery cell from exceeding tolerances due to overflow, thereby ensuring assembly consistency and interchangeability. In summary, this technical solution optimizes the structure of the pressure ring 16 and the partitioned sealing, thereby achieving a reasonable distribution of the compression ratio of the sealant 18. This not only solves the problems of easy lifting, expansion and overflow of the sealant 18 in the prior art, but also improves the sealing performance and structural stability of the component, resulting in a safe, reliable and dimensionally controlled top cover component 10.

[0034] This embodiment discloses a sealing structure design for a battery top cover assembly 10, focusing on limiting and optimizing the thickness and compression parameters of the sealant 18 and the second sealing portion 182. Specifically, the sealant 18 includes a second sealing portion 182, which has an original thickness before compression and is compressed to a thickness T3 after engaging with the second pressing portion 162 (thickness T2) of the pressure ring 16. The thickness of the first pressing portion 161 is T1, and the thickness of the second pressing portion 162 is T2, while satisfying 0.1*T3 < T2. That is, the second pressing portion 162 T2 must be greater than one-tenth of the thickness T3 of the second sealing portion 182 after compression. Through this structural design, it is possible to ensure that the sealant 18 obtains a sufficient compression ratio in the main sealing area (the area of ​​the second pressing portion 162), while obtaining a smaller compression ratio in the auxiliary area (the area of ​​the first pressing portion 161). The difference in compression ratio effectively suppresses the radial expansion of the sealant 18.

[0035] The beneficial effects of this technical solution are reflected in the following aspects: First, by quantitatively limiting the ratio between T2 and T3, a larger compression ratio is ensured to be applied in the main sealing area (second pressure section 162 area), and a smaller compression ratio is applied in the auxiliary area (first pressure section 161 area), forming a reasonable compression gradient. In traditional structures, if the difference in compression ratio is too small, the sealant 18 is prone to radial expansion when subjected to large compression, leading to sealant 18 lifting, overflow, and even affecting the assembly dimensions and sealing performance of the top cover assembly 10. This technical solution, by limiting T2 to 0.1*T3, ensures that the sealant 18 is sufficiently compressed in the second pressure section 162 area to achieve the main seal, while the smaller compression ratio in the first pressure section 161 area effectively constrains the sealant 18, reducing the tendency of the sealant 18 to expand radially.

[0036] Therefore, this technical solution can effectively solve the problems in the existing technology where the sealant 18 is prone to radial expansion, structural loss of control, glue overflow, and dimensional deviation when subjected to single high compression. By scientifically setting the thickness difference of the pressure ring 16 and the parameters of the sealant 18 after compression, a reasonable distribution area of ​​the compression ratio is formed, which not only ensures the main sealing function of the sealant 18, but also maintains the controllability of the deformation of the sealant 18, ultimately achieving improved sealing performance, stable structural dimensions, and reliable assembly process of the top cover assembly 10.

[0037] This embodiment discloses an improved pressure ring 16 structure for a top cover assembly 10. The pressure ring 16 includes a first pressure portion 161, a second pressure portion 162, and a third pressure portion 163. The first pressure portion 161 is located on the outermost side of the pressure ring 16, the second pressure portion 162 is located on the side of the first pressure portion 161 facing the top cover 12, and the third pressure portion 163 is located on the side of the second pressure portion 162 facing the top cover 12, with the third pressure portion 163 located on the innermost side of the pressure ring 16. Simultaneously, the widths of each pressure portion decrease sequentially, with the width of the third pressure portion 163 being smaller than the width of the second pressure portion 162, and the width of the second pressure portion 162 being smaller than the width of the first pressure portion 161. Structurally, the first pressure portion 161, the second pressure portion 162, and the third pressure portion 163 respectively contact the outer peripheral surface of the pole post 14, forming a multi-layered stepped clamping structure.

[0038] In this embodiment, the pressure ring 16 adopts a two-step structure, with the third pressure part 163 located on the innermost side of the pressure ring 16, in the mating area with the pole post 14. The third pressure part 163 increases the contact area between the pressure ring 16 and the pole post 14, thereby providing greater load-bearing capacity and higher structural strength when the pole post 14 is riveted. This design not only enhances the reliability of the mechanical connection between the pressure ring 16 and the pole post 14, but also improves the structural stability and deformation resistance of the overall assembly.

[0039] The above technical solution, by introducing a third pressing part 163 into the pressing ring 16 structure, with the width of the third pressing part 163 being smaller than that of the second pressing part 162, solves the problems of limited contact area, insufficient structural strength, and easy loosening or deformation in existing single-layer or single-step pressing ring 16 structures during the riveting process of the pole post 14. Specifically, the third pressing part 163 increases the contact area between the pressing ring 16 and the outer peripheral surface of the pole post 14, allowing the pressing ring 16 to better cover the pole post 14 during the riveting process, thus improving the fit strength and stability between the pressing ring 16 and the pole post 14. This multi-layer stepped structure can effectively disperse and bear the stress brought by riveting or external loads, preventing loosening, detachment, or sealing failure between the pole post 14 and the pressing ring 16 due to stress concentration.

[0040] It can be seen that the present invention significantly improves the structural reliability of the top cover assembly 10 when the pole post 14 is riveted together by the three-layer structure design of the pressure ring 16, effectively solves the technical problems of insufficient structural strength and poor sealing reliability in the prior art, and finally achieves the technical effect of high strength, stability and sealing reliability of the battery top cover assembly 10 structure.

[0041] This embodiment relates to an improved battery top cover assembly 10 structure, particularly the structural design of the inner hole 124 of the top cover 12 and the sealant 18. Specifically, the inner hole 124 of the top cover 12 has a first hole 125 and a second hole 126, with the second hole 126 located between the first hole 125 and the pressure ring 16. The diameter of the first hole 125 is D1, and the diameter of the second hole 126 is D2, where D2 is greater than D1, i.e., D2 > D1. Thus, the inner hole 124 of the top cover 12 has at least one stepped structure in the axial direction, thereby forming two regions with different inner diameters.

[0042] Regarding the sealant 18, in addition to the first sealing portion 181 and the second sealing portion 182, the sealant 18 also includes a third sealing portion 183. The third sealing portion 183 is connected to the second sealing portion 182 and is located between the pole post 14 and the wall of the inner hole 124 of the top cover 12, serving to fill and seal.

[0043] In this embodiment, when the pole post 14 is inserted into the inner hole 124 of the top cover 12 and riveted after assembly with the pressure ring 16, the inner diameter of the inner hole 124 of the top cover 12 is different at different height positions, resulting in different spacings between the pole post 14 and the top cover 12 in the axial direction (height direction). During the riveting process, the pole post 14 expands under compression. Because the spacing between the pole post 14 and the top cover 12 is larger in region D2, the radial constraint on the pole post 14 during expansion is smaller in this region, resulting in a larger expansion amount. In region D1, due to the smaller spacing, the constraint on the pole post 14 during expansion is larger, resulting in a smaller expansion amount. Thus, the pole post 14 forms different radial expansion states in the height direction, meaning that the pole post 14 exhibits different diameters at different height positions of the top cover 12, enabling better "fitting" and "locking" with the stepped structure of the inner hole 124 of the top cover 12.

[0044] This technical solution effectively solves the technical problems in the traditional top cover 12 and pole post 14 mating structure, such as poor fit between pole post 14 and inner hole 124 of top cover 12, insufficient structural strength, uneven stress on sealant 18, and poor sealing performance during the riveting process of pole post 14.

[0045] Specifically, the stepped structure design of the inner hole 124 of the top cover 12 allows the pole post 14 to form different diameter distributions in the height direction after riveting, which coincide with the different diameter areas of the inner hole 124 of the top cover 12. This significantly improves the mechanical interlocking strength between the pole post 14 and the top cover 12, enhancing the overall structural strength of the top cover assembly 10. Furthermore, the area with a larger gap between the bottom circle of the pole post 14 and the inner hole 124 of the top cover 12 expands sufficiently, enabling greater pressure to be applied to the sealant 18 (especially the third sealing portion 183), significantly improving the clamping effect of the sealant 18, thereby enhancing the sealing performance of the cover assembly.

[0046] In summary, the present invention, through the stepped structure of the inner hole 124 and the design of the third dense part 183 of the sealant 18, makes the pole post 14 and the top cover 12 fit more tightly after riveting, increases the pressure of the bottom circle of the pole post 14 on the sealant 18, effectively improves the sealing performance and structural reliability of the cover assembly, and achieves synergistic optimization of structural strength and sealing performance.

[0047] This embodiment relates to an improvement in the structure of a battery top cover 12, specifically an optimized design of the stepped transition portion of the inner hole 124 of the top cover 12. The inner hole 124 of the top cover 12 includes a first hole 125 and a second hole 126. The diameter of the first hole 125 is smaller than the diameter of the second hole 126, and the two form a stepped structure in the axial direction. To improve the adhesion and sealing effect of the sealant 18, especially the third sealing portion 183, at the stepped portion, a chamfer 127 is provided at the connection between the first hole 125 and the second hole 126. This chamfer 127 can be designed as a beveled angle, forming a slope at the connection, or it can be designed as a rounded corner, forming a smooth arc surface at the connection. The specific form and size of the chamfer 127 can be optimized and adjusted according to the actual performance of the sealant 18 and the manufacturing process requirements. By setting a chamfer 127 in this transition area, the third dense portion 183 of the sealant 18 can smoothly transition from the first hole 125 to the second hole 126, avoiding uneven filling or stress concentration of the sealant 18 caused by abrupt step changes, thereby ensuring the continuity and density of the sealing layer. In the actual assembly process, the sealant 18 can naturally spread and fill along the chamfer 127, so that the pole post 14 and the inner hole 124 wall of the top cover 12 can maintain a good sealing effect throughout the entire height direction.

[0048] By adding a chamfer 127 at the connection between the first hole 125 and the second hole 126, this technical solution effectively solves the problems of stress concentration, insufficient filling, and poor sealing of the sealant 18 at the transition point in traditional stepped structures. The smooth transition of the chamfer 127 not only avoids damage or peeling of the sealant 18 caused by abrupt changes in the step, but also makes the distribution of the sealant 18 in this area more uniform, thereby significantly improving the sealing performance and structural reliability of the transition area between the terminal post 14 and the top cover 12. At the same time, the chamfer 127 structure also enhances the flowability and adhesion of the sealant 18 during assembly, improves the consistency and fault tolerance of the product manufacturing process, and reduces sealing defects caused by process fluctuations. In summary, this technical solution achieves smooth and dense adhesion of the sealant 18 at the step transition point through the chamfer 127 design, significantly improving the sealing performance and structural stability of the cover assembly, and ensuring the safety and reliability of the battery cover assembly during use.

[0049] This embodiment relates to an improved sealing structure for a battery cover assembly. In this sealing structure, the sealant 18 includes not only the conventional first sealing portion 181 and second sealing portion 182, but also a third sealing portion 183 and a fourth sealing portion 184. Specifically, the third sealing portion 183 is connected to the second sealing portion 182, and in the assembled state, the third sealing portion 183 is disposed between the wall of the terminal post 14 and the inner hole 124 of the top cover 12, forming a sealing band surrounding the terminal post 14. The fourth sealing portion 184 is connected to the third sealing portion 183, and is located between the second end 142 of the terminal post 14 and the top cover 12, thus forming an effective seal between the end of the terminal post 14 and the surface of the top cover 12. In this way, the sealing portions of the sealant 18, through a continuous structure, completely cover the key interface area between the terminal post 14 and the top cover 12. The third sealing portion 183 provides a longitudinal seal, and the fourth sealing portion 184 further seals the gap between the end of the terminal post 14 and the surface of the top cover 12, improving the overall sealing effect.

[0050] In practical implementation, the sealant 18 can be manufactured using a molding process to ensure a tight fit between the third sealing portion 183 and the fourth sealing portion 184 and the pole post 14 and the top cover 12. The dimensions of the third sealing portion 183 are designed based on the gap between the pole post 14 and the inner hole 124 to ensure that it can fully fill the area and achieve a tight seal. The fourth sealing portion 184 is designed based on the space between the second end 142 and the top cover 12 to form a reliable sealing barrier between the end of the pole post 14 and the top cover 12.

[0051] By adding a third sealing portion 183 and a fourth sealing portion 184 to the sealant 18 structure, this technical solution effectively solves the technical problems of insufficient sealing, easy leakage, and poor sealing reliability in existing battery cover assembly sealing structures, such as insufficient sealing between the terminal post 14 and the inner hole 124 wall, and between the end of the terminal post 14 and the top cover 12. The third sealing portion 183 allows the sealant 18 to fully fill the annular space between the terminal post 14 and the inner hole 124 wall, forming a longitudinal sealing band, thereby blocking the path of liquid or gas leakage along this direction. The fourth sealing portion 184 further covers the gap between the second end 142 of the terminal post 14 and the top cover 12, achieving sealing in the end face direction and effectively preventing sealing dead zones or localized leakage in this area.

[0052] In summary, this technical solution provides comprehensive sealing of the critical interface between the terminal post 14 and the top cover 12 through the third sealed portion 183 and the fourth sealed portion 184, making the sealing structure more perfect, significantly improving the sealing performance and structural reliability of the battery cover assembly, reducing the risk of failure due to poor sealing, and ensuring the safety and service life of the product.

[0053] This embodiment relates to an improvement in the sealing structure of the terminal post 14 and the top cover 12 for a small-diameter needle-type battery. Specifically, a raised ring 143 is provided on the side of the second end 142 of the terminal post 14 facing the top cover 12. The raised ring 143 is located at the bottom of the terminal post 14 and corresponds to the fourth dense portion 184 of the sealant 18 during assembly. The main function of the raised ring 143 is to further compress the fourth dense portion 184 in a localized area, thereby increasing the compression ratio of that area. That is, in the area of ​​the fourth dense portion 184 corresponding to the raised ring 143, the compression ratio of the sealant 18 is significantly higher than that in the area without the raised ring 143, thus forming a locally high-compression sealing band.

[0054] In actual manufacturing, the protruding ring 143 at the bottom of the pole post 14 can be obtained through various material forming methods, such as stamping, turning, or welding. These processing methods ensure the structural strength of the pole post 14 while precisely forming the required protruding ring 143 structure. During assembly, the fourth dense portion 184 is compressed by the protruding ring 143 under axial force, resulting in a greater compression ratio in this area than in the surrounding areas not compressed by the protruding ring 143.

[0055] Through the above structural design, the compression ratio of the fourth dense part 184 in the non-convex ring 143 area is small, which can reduce the expansion of the sealant 18 in the diameter direction, thereby avoiding the out-of-tolerance outer diameter of the small-diameter needle battery caused by the expansion of the sealant 18, thus improving the dimensional consistency and appearance quality of the product.

[0056] This technical solution effectively solves the technical problems of insufficient local sealing performance or overall dimensional instability caused by uneven compression of the sealant 18 in small-diameter needle-type battery applications due to the provision of a convex ring 143 on the side of the second end 142 of the electrode post 14 facing the top cover 12. The convex ring 143 forms a locally high compression ratio zone over the fourth dense portion 184. The increased compression ratio of the fourth dense portion 184 under the convex ring 143 significantly enhances the sealing ability of this area and reduces the risk of leakage. Simultaneously, the area outside the convex ring 143 maintains a smaller compression ratio, reducing the expansion effect of the sealant 18 in the diameter direction, thereby effectively controlling the outer diameter of the battery and preventing sealant 18 overflow or battery dimensions exceeding tolerances.

[0057] In summary, this technical solution achieves localized optimized compression of the fourth dense part 184 of the sealant 18 by rationally setting the convex ring 143 structure at the bottom of the electrode post 14. This not only improves sealing reliability but also optimizes the control of the battery's appearance dimensions, enhances product consistency and reliability, and meets the application requirements of high sealing performance and high dimensional accuracy for small-diameter needle batteries.

[0058] This embodiment relates to an improved structural design of a small-diameter needle-type battery top cover 12 and housing 30. Specifically, the top cover 12 includes a first cover portion 121 and a second cover portion 122 connected to each other, wherein the first cover portion 121 is located between the cell pack 20 and the second cover portion 122, and the outer diameter D3 of the first cover portion 121 is smaller than the outer diameter D4 of the second cover portion 122. The structure of the top cover 12 is stepped in the axial direction, having at least one stepped structure, that is, including at least two different outer diameters: D3 and D4. During assembly, the outer diameter D4 of the second cover portion 122 of the top cover 12 is in close contact with the inner wall of the housing 30, achieving precise fitting and sealing, while the outer diameter D3 of the first cover portion 121 is spaced apart from the inner wall of the housing 30, not directly contacting the housing 30, thereby providing additional space for the cell pack 20. The thickness T3 of the housing 30 matches the dimensions of the top cover 12, ensuring that the second cover portion 122 and the inner wall of the housing 30 form a reliable positioning structure. The top cover 12 can be manufactured through processes such as metal stamping, turning, or integral molding. During assembly, it is fixed and sealed by the interference fit between the second cover 122 and the housing 30, while the first cover 121 does not affect the minimum diameter of the housing 30. The above structure innovatively utilizes the stepped design of the top cover 12 to optimize the fit between the top cover 12 and the housing 30.

[0059] This technical solution effectively solves the problems of large battery diameter, low energy density, and insufficient sealing reliability caused by the traditional battery top cover 12 fitting with the housing 30, through the stepped structure design of the top cover 12. On one hand, the outer diameter D3 of the first cover 121 is smaller than the outer diameter D4 of the second cover 122, and it is spaced apart from the inner wall of the housing 30, allowing for a reduction in the diameter of most areas of the battery, thus significantly reducing the overall outer diameter of the battery and facilitating miniaturization. On the other hand, this stepped structure improves the utilization rate of the battery's internal space, allowing the core pack 20 to occupy more internal volume and increasing the energy density per unit volume. Furthermore, the precise fit of the second cover 122 with the inner wall of the housing 30 enhances the positioning and sealing capabilities of the top cover 12, preventing electrolyte leakage and improving battery safety and reliability. Structurally, the stepped design facilitates automated assembly, improving production efficiency and product consistency. In summary, this technical solution optimizes the fit between the top cover 12 and the housing 30, thereby reducing the overall diameter of the battery, increasing the energy density, enhancing sealing performance and assembly reliability, and achieving structural optimization and performance improvement for small high-energy-density needle-shaped batteries.

[0060] This embodiment proposes an optimized design for the wall thickness and step size of the top cover 12 in the mating structure of the battery casing 30 and the top cover 12. Specifically, the wall thickness of the battery casing 30 is T4, the outer diameter of the second cover portion 122 of the top cover 12 is D4, and the outer diameter of the first cover portion 121 is D3. The difference between the two (D4-D3) represents the size of the step structure of the top cover 12. According to this technical solution, the wall thickness T4 of the casing 30 and the step size (D4-D3) of the top cover 12 satisfy the following relationship: 0.1*T4 < (D4-D3). That is, the step size of the top cover 12 is greater than one-tenth of the wall thickness of the casing 30. By setting these structural parameters, the step structure between the top cover 12 and the casing 30 can be ensured to be neither too thin, resulting in insufficient strength and sealing, nor too thick, affecting the utilization rate of the battery's internal space, thereby achieving a balance between structural strength, assembly reliability, and space utilization.

[0061] By adopting this technical solution, the step size (D4-D3) of the top cover 12 is greater than one-tenth of the wall thickness of the housing 30, effectively solving the technical problems caused by the top cover 12 being too thin or too thick in traditional designs. When the step size is too small, the fitting area between the top cover 12 and the housing 30 is insufficient, resulting in poor sealing, increased assembly difficulty, and reduced mechanical strength, thus affecting the safety and reliability of the battery. This solution, by setting a lower limit for the step size, ensures that the fitting area of ​​the top cover 12 has sufficient width, achieving a stable fit and effective sealing, improving assembly consistency and battery lifespan. At the same time, this proportional relationship also prevents the step size from being too large and occupying internal space, maintaining the compactness of the internal structure, which is conducive to improving energy density. Overall, this technical solution, through the optimized matching of wall thickness and step size, takes into account structural strength, sealing effect, and space utilization, significantly improving the miniaturization, safety, and energy density of battery products.

[0062] This embodiment relates to a structural design of a battery top cover 12 and a housing 30. Specifically, the top cover 12 sequentially includes a first cover portion 121, a second cover portion 122, and a third cover portion 123, wherein the third cover portion 123 is located on the side of the second cover portion 122 away from the first cover portion 121. The diameter D5 of the third cover portion 123 is larger than the diameter D4 of the second cover portion 122, thus the third cover portion 123 has an outwardly flared structure relative to the second cover portion 122. During assembly, the third cover portion 123 overlaps the top surface of the housing 30, that is, the lower surface of the third cover portion 123 is in contact with the top surface of the opening 32 end of the housing 30. In this way, the third cover portion 123 not only covers the top surface of the housing 30, but also provides a limiting function for the top cover 12, preventing the top cover 12 from axially moving due to external force or internal pressure during assembly or use.

[0063] This technical solution solves the problems of axial displacement of the top cover 12, difficulty in precise positioning of the top cover 12 after assembly, and insufficient sealing reliability in the prior art by setting a third cover portion 123 on the top cover 12 that extends outward and overlaps with the top surface of the housing 30. Specifically, the overlapping structure of the third cover portion 123 significantly increases the contact area between the top cover 12 and the housing 30, enabling the top cover 12 to achieve axial stop through direct contact between the third cover portion 123 and the top surface of the housing 30 after assembly. This prevents the top cover 12 from axially shifting due to vibration, pressure, or thermal expansion and contraction, thereby improving the stability and safety of the battery structure. In addition, the increased overlapping area of ​​the third cover portion 123 can further improve the sealing effect, reduce the risk of electrolyte leakage, and enhance the battery's lifespan and reliability. Therefore, this technical solution, through the reasonable structural design of the third cover portion 123, achieves effective positioning and auxiliary sealing of the top cover 12, improving the overall assembly accuracy, safety, and sealing performance of the battery product.

[0064] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0065] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0066] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0067] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A top cover assembly, characterized in that, The top cover assembly includes: The top cover has an inner hole; A pole post, passing through the inner hole, has a first end and a second end disposed opposite to each other; A pressure ring, connected to the first end of the pole post, the pressure ring including a first pressure portion and a second pressure portion, the second pressure portion being disposed on the side of the first pressure portion facing the top cover, and the width of the second pressure portion being smaller than the width of the first pressure portion; and The sealant includes a first sealed portion and a second sealed portion that are connected to each other. The first sealed portion is pressed between the first sealed portion and the top cover, and the second sealed portion is pressed between the second sealed portion and the top cover.

2. The top cover assembly according to claim 1, characterized in that, The thickness of the first pressing part is T1, the thickness of the second pressing part is T2, the thickness of the second pressing part is T3, and 0.1*T3<T2.

3. The top cover assembly according to claim 1, characterized in that, The pressure ring further includes a third pressure part, which is disposed on the side of the second pressure part facing the top cover. The width of the third pressure part is smaller than the width of the second pressure part. The first pressure part, the second pressure part, and the third pressure part are in contact with the outer peripheral surface of the pole post, respectively.

4. The top cover assembly according to claim 1, characterized in that, The inner hole includes a first hole and a second hole, the second hole being located between the first hole and the pressure ring, and the diameter D1 of the first hole being smaller than the diameter D2 of the second hole; The sealant also includes a third sealed portion, which is connected to the second sealed portion and is located between the pole and the wall of the inner hole.

5. The top cover assembly according to claim 4, characterized in that, A chamfer is provided at the connection between the first hole and the second hole.

6. The top cover assembly according to any one of claims 1 to 5, characterized in that, The sealant also includes a third and a fourth sealed portion. The third sealed portion is connected to the second sealed portion and is located between the pole post and the wall of the inner hole. The fourth sealed portion is connected to the third sealed portion and is located between the second end and the top cover.

7. The top cover assembly according to claim 6, characterized in that, The second end is provided with a protruding ring on the side facing the top cover, and the protruding ring further presses against the fourth dense part.

8. A battery, characterized in that, The battery includes a housing, a core pack, and a top cover assembly as described in any one of claims 1 to 7, wherein the housing has a receiving cavity and an opening communicating with the receiving cavity, the core pack is disposed in the receiving cavity, and the top cover assembly is connected to the housing and covers the opening.

9. The battery according to claim 8, characterized in that, The top cover includes a first cover portion and a second cover portion connected to each other. The first cover portion is located between the core package and the second cover portion. The diameter D3 of the first cover portion is smaller than the diameter D4 of the second cover portion. The first cover portion is spaced apart from the inner wall of the housing, and the second cover portion is in contact with the inner wall of the housing.

10. The battery according to claim 9, characterized in that, The wall thickness of the shell is T4, and 0.1*T4 < (D4-D3).

11. The battery according to claim 9, characterized in that, The top cover includes a third cover portion, which is connected to the side of the second cover portion away from the first cover portion. The diameter D5 of the third cover portion is larger than the diameter D4 of the second cover portion, and the third cover portion overlaps the top surface of the housing.

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