Cylindrical battery coating structure and cylindrical lithium ion battery

Abstract

The utility model relates to a cylindrical battery coating structure and a cylindrical lithium ion battery, and belongs to the technical field of cylindrical batteries. The cylindrical battery coating structure comprises a sleeve, and the sleeve is arranged on the periphery of a cylindrical battery in a sleeving manner; two ends of the sleeve in the length direction correspondingly cover the outer edge of the positive end face and the outer edge of the negative end face of the cylindrical battery; the radial section area of the cylindrical battery after being sleeved with the sleeve is S0, the area, wrapped by the sleeve, of the end face of the positive electrode end of the cylindrical battery is a first area, the area of the first area is S1, the area, not wrapped by the sleeve, of the end face of the negative electrode end of the cylindrical battery is a second area, the area of the second area is S10, and the ratio of S1 to S0 is larger than or equal to 40% and smaller than or equal to 60%; the ratio of S10 to S0 is greater than or equal to 41% and less than or equal to 61%. According to the cylindrical battery coating structure and the cylindrical lithium ion battery provided by the utility model, the sleeve has a good coating effect on the positive electrode end and the negative electrode end of the cylindrical battery.

Description

A cylindrical battery coating structure and a cylindrical lithium-ion battery Technical Field

[0001] This utility model belongs to the field of cylindrical battery technology, and particularly relates to a cylindrical battery coating structure and a cylindrical lithium-ion battery. Background Technology

[0002] In the production and application of cylindrical batteries, a film or sleeve is usually applied to the surface of the cylindrical battery. On the one hand, this provides insulation protection for the battery, effectively preventing short circuits caused by contact between the battery casing and external conductors, and ensuring battery safety. On the other hand, it also provides mechanical protection, reducing damage to the battery caused by collisions and friction during production, transportation and use, while isolating it from corrosive substances such as moisture and oxygen, thus extending the battery's lifespan.

[0003] However, in practical applications, it has been found that the design of the cylindrical battery coating structure ratio is crucial. When the coating ratio is too small, the coverage area of ​​the cylindrical battery sleeve for the positive and negative terminals is insufficient. Especially during battery cycle charging and discharging, the battery ends generate significant heat, and the sleeve shrinks due to heat, further exacerbating the coating problem and leading to a decrease in battery safety and stability. If the coating ratio is too large, it will increase the sleeve flange amount, which not only significantly increases the amount of sleeve used, leading to increased battery cost and weight, and thus reducing battery energy density and affecting battery performance, but also affects the battery's appearance. In addition, an excessively large coating ratio will cause the sleeve to be too close to the top cover plate. Given the unavoidable tolerances in the assembly process, it is very easy to cause interference between the sleeve and the top cover plate, seriously affecting the assembly process and leading to a significant decrease in battery assembly yield. Although patent CN116315139A discloses coating the battery surface with an insulating film, it does not provide a reasonable design for the relevant dimensions of the insulating film and the coating ratio.

[0004] Therefore, a reasonable design of the coating ratio is of great significance for balancing battery safety, stability, cost control, performance optimization, and assembly yield. Summary of the Invention

[0005] In view of the shortcomings of related technologies, this utility model provides a cylindrical battery coating structure and a cylindrical lithium-ion battery, so as to reasonably design the coating size of the sleeve to the positive and negative terminals of the cylindrical battery.

[0006] This utility model provides a cylindrical battery encapsulation structure, including:

[0007] A sleeve is fitted around the outer periphery of a cylindrical battery; the two ends of the sleeve along its length are corresponding to the positive and negative terminals of the cylindrical battery, and the two ends of the sleeve cover the outer edges of the positive terminal face and the outer edges of the negative terminal face of the cylindrical battery.

[0008] The radial cross-sectional area of ​​the cylindrical battery after being fitted with a sleeve is S0. The area of ​​the positive terminal end face of the cylindrical battery covered by the sleeve is the first region, and the area of ​​the first region is S1. The area of ​​the negative terminal end face of the cylindrical battery not covered by the sleeve is the second region, and the area of ​​the second region is S10. The ratio of S1 to S0 is greater than or equal to 40% and less than or equal to 60%, and the ratio of S10 to S0 is greater than or equal to 41% and less than or equal to 61%.

[0009] This technical solution ensures that the ratio of the area S1 of the first region to the radial cross-sectional area S0 of the cylindrical battery after the sleeve is installed is between 40% and 60%. This ensures that the ratio of the area covered by the sleeve on the positive terminal of the cylindrical battery to the radial cross-sectional area S0 is between 40% and 60%. This not only allows the sleeve to effectively cover the positive terminal of the cylindrical battery, avoiding poor coverage caused by heat generated during cyclic charging and discharging, but also avoids increased cost, weight, and aesthetic impact due to excessively large coverage area, as well as assembly interference problems. Furthermore, by ensuring that the ratio of the area S10 of the second region to the radial cross-sectional area S0 of the cylindrical battery after the sleeve is installed is between 41% and 61%, this solution ensures that the ratio of the area not covered by the sleeve on the negative terminal of the cylindrical battery to the radial cross-sectional area S0 is between 41% and 61%. This avoids the cost, weight, aesthetic, and poor coverage problems caused by an excessively large or small coverage area of ​​the sleeve on the negative terminal of the cylindrical battery.

[0010] In some embodiments, the first region is annular, and the difference between the outer diameter R0 and the inner diameter R1 of the first region is greater than or equal to 2 mm and less than or equal to 4 mm.

[0011] This technical solution ensures that the difference between the outer diameter R0 and the inner diameter R1 of the first region is between 2mm and 4mm, so that the film width of the sleeve at the positive end of the cylindrical battery is between 2mm and 4mm. This prevents poor coverage due to insufficient coverage area, and avoids increased cost, weight and aesthetic impact due to excessive coverage area.

[0012] In some embodiments, the cylindrical battery has a face pad and a cap located at the positive terminal of the cylindrical battery. The sleeve and the face pad are in contact with each other on the side away from the interior of the cylindrical battery, and the outer edge of the face pad is covered by the sleeve. The cap is located on the side away from the interior of the cylindrical battery, and the outer edge of the cap is covered by the face pad. The area of ​​the face pad not covered by the sleeve is a third region, and the area of ​​the third region is S2. The ratio of S2 to S0 is greater than or equal to 13% and less than or equal to 25%.

[0013] This technical solution ensures that the ratio of the area S2 of the third region to the radial cross-sectional area S0 of the cylindrical battery after the sleeve is installed is between 10% and 26%, and that the ratio of the area of ​​the pad not covered by the sleeve to the radial cross-sectional area S0 of the cylindrical battery after the sleeve is installed is between 10% and 26%. This allows the sleeve to effectively cover the pad, improves the probability of positive and negative electrode insulation, reduces the risk of short circuit, and avoids interference between the pad and the bulge affecting assembly.

[0014] In some embodiments, the difference between the inner diameter R1 of the first region and the inner diameter R2 of the third region is greater than or equal to 0.8 mm and less than or equal to 2.4 mm.

[0015] In some embodiments, the cap includes a bulge and a skirt, the bulge being located on the outer periphery of the skirt and protruding in a direction away from the center of the skirt, the minimum distance from the bulge to the third region being L3, and the ratio of L3 to R0 being greater than or equal to 3% and less than or equal to 12%.

[0016] This technical solution ensures that the ratio of the minimum distance L3 from the convex hull to the third region to R0 is between 3% and 12%, thereby preventing interference between the face pad and the convex hull from affecting assembly, while also guaranteeing effective coverage of the face pad by the sleeve and insulation between the positive and negative poles.

[0017] In some embodiments, the minimum distance from the skirt edge to the third region is L4, and the ratio of L4 to RO is greater than or equal to 5% and less than or equal to 20%.

[0018] This technical solution ensures that the ratio of the minimum distance L4 from the skirt to the third region to R0 is between 5% and 20%, thereby avoiding interference between the face pad and the skirt that could affect assembly, and guaranteeing effective coverage of the sleeve over the face pad and insulation between the positive and negative poles.

[0019] In some embodiments, the minimum distance from the skirt edge to the first region is L10, and the ratio of L10 to R0 is greater than or equal to 20% and less than or equal to 35%.

[0020] This technical solution controls the amount of sleeve used by keeping the ratio of the minimum distance L10 from the skirt to the first area to R0 between 20% and 35%, thereby avoiding increased cost, weight, and aesthetic issues, while ensuring effective coverage of the negative end.

[0021] In some embodiments, the minimum distance from the convex hull to the first region is L11, and the ratio of L11 to R0 is greater than or equal to 16% and less than or equal to 28%.

[0022] This technical solution controls the amount of sleeve used by keeping the ratio of the minimum distance L11 from the convex hull to the first region to R0 between 10% and 30%, thereby avoiding increased cost, weight, and aesthetic issues, while ensuring effective coverage of the negative end.

[0023] In some embodiments, the outer diameter R3 of the second region is greater than or equal to 6.5 mm and less than or equal to 8.5 mm.

[0024] In addition, this utility model also provides a cylindrical lithium-ion battery, including the above-mentioned cylindrical battery coating structure.

[0025] Based on the above technical solution, the cylindrical battery coating structure of this utility model, through reasonable design of the ratio of the coverage area of ​​the sleeve to the positive and negative terminals of the cylindrical battery, can ensure that the sleeve effectively covers the positive and negative terminals of the cylindrical battery, avoiding the problem of poor coverage caused by heat generation during cyclic charging and discharging, while avoiding the increase in cost, weight and aesthetic impact due to excessive coverage area, as well as the problem of assembly interference. Attached Figure Description

[0026] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0027] Figure 1 is a schematic diagram of the structure of the positive terminal of a cylindrical battery after coating according to this utility model;

[0028] Figure 2 is a schematic diagram of the dimensions of the positive terminal of a cylindrical battery after being coated according to this utility model;

[0029] Figure 3 is a magnified view of part A in Figure 2;

[0030] Figure 4 is a magnified view of part B in Figure 2;

[0031] Figure 5 is a schematic diagram of the negative terminal of a cylindrical battery after coating according to this utility model;

[0032] Figure 6 is a schematic diagram of the dimensions of the negative terminal of a cylindrical battery after coating according to this utility model.

[0033] In the picture:

[0034] 1. Sleeve; 2. Gasket; 3. Convex bulge; 4. Skirt; 5. Steel shell;

[0035] 101. First area; 102. Second area; 103. Third area. Detailed Implementation

[0036] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. 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.

[0037] In the description of this utility model, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0038] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0040] As shown in Figures 1-6, in an illustrative embodiment of a cylindrical battery encapsulation structure according to the present invention, the cylindrical battery encapsulation structure includes a sleeve 1, which is sleeved on the outer periphery of the cylindrical battery; the two ends of the sleeve 1 in the length direction are correspondingly arranged with the positive and negative terminals of the cylindrical battery, and the two ends of the sleeve 1 in the length direction extend beyond the positive and negative terminals of the cylindrical battery, so that the two ends of the sleeve 1 cover the outer edge of the positive terminal end face and the outer edge of the negative terminal end face of the cylindrical battery respectively.

[0041] In some embodiments, the bushing 1 is made of polyethylene terephthalate to give it high strength and toughness, enabling it to withstand certain external forces of tension and compression, making it less prone to breakage or deformation. It can also effectively isolate current, prevent electrical accidents such as leakage and short circuits, ensure the safe operation of electrical equipment and lines, and resist chemical corrosion and high temperature.

[0042] As shown in Figure 2, the radial cross-sectional area of ​​the cylindrical battery after being fitted with sleeve 1 is S0. The area of ​​the positive end face of the cylindrical battery covered by sleeve 1 is the first region 101, and the area of ​​the first region 101 is S1. The ratio of S1 to S0 is greater than or equal to 40% and less than or equal to 60%.

[0043] If the ratio of S1 to S0 is too small, the coverage area of ​​the sleeve 1 on the positive terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the positive terminal, thus resulting in poor coverage of the positive terminal of the cylindrical battery by the sleeve 1.

[0044] If the ratio of S1 to S0 is too large, the coverage area of ​​the sleeve 1 on the positive terminal of the cylindrical battery will be too large. This will not only increase the amount of sleeve 1 used, increasing the cost and weight of the cylindrical battery and reducing its energy density, but also affect the aesthetics of the cylindrical battery. Furthermore, an excessively large ratio of S1 to S0 can also lead to the sleeve 1 being too close to the top cover. During assembly, there are certain tolerances in the assembly process between the sleeve 1 and the cylindrical battery, which can easily cause interference between the sleeve 1 and the protrusion 3 of the cover, affecting assembly and reducing the battery assembly yield.

[0045] In some embodiments, the outer diameter of the cylindrical battery after being fitted with sleeve 1 is 10.58 mm, and the radial cross-sectional area S0 of the cylindrical battery after being fitted with sleeve 1 is 351.66 mm². 2 .

[0046] The first region 101 is annular. The outer diameter of the cylindrical battery after the sleeve 1 is installed is the outer diameter R0 of the first region 101. The difference between the outer diameter R0 and the inner diameter R1 of the first region 101 can also be considered as the width of the first region 101, or as the coating width L1 of the sleeve 1 at the positive end of the cylindrical battery.

[0047] As shown in Figures 3 and 4, the difference between the outer diameter R0 and the inner diameter R1 of the first region 101 is greater than or equal to 2 mm and less than or equal to 4 mm, that is, the film width L1 of the sleeve 1 at the positive terminal of the cylindrical battery is greater than or equal to 2 mm and less than or equal to 4 mm.

[0048] If the width L1 of the sleeve 1 at the positive terminal of the cylindrical battery is too small, the coverage area of ​​the sleeve 1 at the positive terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 at the positive terminal, thus resulting in poor coverage of the positive terminal of the cylindrical battery by the sleeve 1.

[0049] If the width L1 of the sleeve 1 at the positive terminal of the cylindrical battery is too large, the coverage area of ​​the sleeve 1 at the positive terminal of the cylindrical battery will be too large. This will not only increase the amount of sleeve 1 used, increasing the cost and weight of the cylindrical battery and reducing the energy density of the battery, but will also affect the aesthetics of the cylindrical battery.

[0050] In some embodiments, the width of the sleeve 1 at the positive terminal of the cylindrical battery is 3 mm. When the outer diameter of the cylindrical battery after sleeve 1 is applied is 10.58 mm, the outer diameter R0 of the first region 101 is 10.58 mm; the inner diameter R1 of the first region 101 is 7.58 mm; and the area S1 of the first region 101 is 171.16 mm². 2 The ratio of S1 to S0 is 49%.

[0051] As shown in Figure 1, the cylindrical battery has a face pad 2 and a cap. The face pad 2 and the cap are located at the positive terminal of the cylindrical battery. The sleeve 1 and the side of the face pad 2 facing away from the inside of the cylindrical battery are in contact with each other, and the outer edge of the face pad 2 is covered by the sleeve 1. The cap is located on the side facing away from the inside of the cylindrical battery, and the outer edge of the cap is covered by the face pad 2. The area of ​​the face pad 2 not covered by the sleeve 1 is the third region 103.

[0052] In some embodiments, the face pad 2 has an annular structure, with the outer edge of the face pad 2 covered by the sleeve 1 and the inner edge of the face pad 2 covered by the cap.

[0053] It should be noted that the difference between the inner diameter R1 of the first region 101 and the inner diameter R2 of the third region 103 can also be considered as the width L2 of the third region 103, that is, the width of the pad 2 not covered by the sleeve 1.

[0054] It should also be noted that the structure and composition of the cap are common knowledge in this field and will not be elaborated here.

[0055] As shown in Figures 2-4, the cap includes a top cover plate, the outer edge of which is covered by a face pad 2. The top cover plate has a protrusion 3 and a skirt 4. The protrusion 3 is located on the outer periphery of the skirt 4 and protrudes in a direction away from the center of the skirt 4. There are multiple protrusions 3, which are evenly distributed along the circumference of the skirt 4.

[0056] The area of ​​the third region 103 is S2, and the ratio of S2 to S0 is greater than or equal to 13% and less than or equal to 25%.

[0057] If the ratio of S2 to S0 is too small, the width of the third region 103 will be small, and the contact area between the sleeve 1 and the pad 2 will be small. This will prevent the sleeve 1 from effectively covering the pad 2, reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery, and increase the risk of short circuit between the positive and negative electrodes.

[0058] If the ratio of S2 to S0 is too large, the width of the third region 103 will be large, and the pad 2 will easily interfere with the convex 3, affecting the assembly and reducing the assembly yield of the battery.

[0059] In some embodiments, the inner diameter R2 of the third region 103 is 5.9 mm, and the area S2 of the third region 103 is 112.34 mm². 2The ratio of S2 to S0 is 19%.

[0060] The difference between the inner diameter R1 of the first region 101 and the inner diameter R2 of the third region 103 is greater than or equal to 0.8 mm and less than or equal to 2.4 mm, that is, the width L2 of the third region 103 is greater than or equal to 0.8 mm and less than or equal to 2.4 mm.

[0061] If the width L2 of the third region 103 is too small, the contact area between the sleeve 1 and the pad 2 will be small, which will prevent the sleeve 1 from effectively covering the pad 2, reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery, and increase the risk of short circuit between the positive and negative electrodes.

[0062] If the width L2 of the third region 103 is too large, the pad 2 is prone to interference with the convex 3, affecting the assembly and reducing the battery assembly yield.

[0063] In some embodiments, the width of the third region 103 is 1.6 mm.

[0064] As shown in Figure 3, the minimum distance from the convex hull 3 to the third region 103 is L3, and the ratio of L3 to R0 is greater than or equal to 3% and less than or equal to 12%.

[0065] If the ratio of L3 to R0 is too small, the distance between the pad 2 and the convex pack 3 will be too close. Since there are certain tolerances in the assembly process, the close distance between the pad 2 and the convex pack 3 will easily cause interference between the pad 2 and the convex pack 3, affecting the assembly and reducing the assembly yield of the battery.

[0066] If the ratio of L3 to R0 is too large, the distance between the pad 2 and the convex 3 will be too far, resulting in a reduction in the contact area between the sleeve 1 and the pad 2. The sleeve 1 will not be able to effectively cover the pad 2, which will also reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery and increase the risk of short circuit between the positive and negative electrodes.

[0067] The minimum distance L3 from the convex hull 3 to the third region 103 is greater than or equal to 0.4 mm and less than or equal to 1.2 mm.

[0068] If the minimum distance L3 between the convex bud 3 and the third region 103 is too small, the distance between the pad 2 and the convex bud 3 will be too close. Since there are certain tolerances in the assembly process, the close distance between the pad 2 and the convex bud 3 will easily cause interference between the pad 2 and the convex bud 3, affecting the assembly and reducing the assembly yield of the battery.

[0069] If the minimum distance L3 from the convex hull 3 to the third region 103 is too large, the distance between the pad 2 and the convex hull 3 will be too far, resulting in a reduction in the contact area between the sleeve 1 and the pad 2. The sleeve 1 will not be able to effectively cover the pad 2, which will also reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery and increase the risk of short circuit between the positive and negative electrodes.

[0070] In some embodiments, the minimum distance L3 from the convex hull 3 to the third region 103 is 0.8 mm, and the ratio of L3 to R0 is 11.3%.

[0071] As shown in Figure 3, the minimum distance from the convex hull 3 to the first region 101 is L11, and the ratio of L11 to R0 is greater than or equal to 16% and less than or equal to 28%.

[0072] If the ratio of L11 to R0 is too small, the amount of sleeve 1 used will increase, which will not only increase the cost and weight of the cylindrical battery and reduce the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0073] If the ratio of L11 to R0 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the negative terminal of the cylindrical battery by the sleeve 1.

[0074] The minimum distance L11 from the convex hull 3 to the first region 101 is greater than or equal to 1.4 mm and less than or equal to 3.4 mm.

[0075] If the minimum distance L11 from the convex hull 3 to the first region 101 is too small, the amount of sleeve 1 used will increase, which will not only increase the cost and weight of the cylindrical battery and reduce the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0076] If the minimum distance L11 from the convex bulge 3 to the first region 101 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the sleeve 1 on the negative terminal of the cylindrical battery.

[0077] In some embodiments, the minimum distance L11 from the convex hull 3 to the first region 101 is 2.4 mm, and the ratio of L11 to R0 is 22.7%.

[0078] As shown in Figure 4, the minimum distance from the skirt edge 4 to the third region 103 is L4, and the ratio of L4 to RO is greater than or equal to 5% and less than or equal to 20%.

[0079] If the ratio of L4 to R0 is too small, the distance between the pad 2 and the skirt 4 will be too close. Since there are certain tolerances in the assembly process, the close distance between the pad 2 and the skirt 4 will easily cause interference between the pad 2 and the skirt 4, affecting the assembly and reducing the assembly yield of the battery.

[0080] If the ratio of L4 to R0 is too large, the distance between the face pad 2 and the skirt 4 will be too far, resulting in a reduction in the contact area between the sleeve 1 and the face pad 2. The sleeve 1 will not be able to effectively cover the face pad 2, which will also reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery and increase the risk of short circuit between the positive and negative electrodes.

[0081] The minimum distance L4 from the skirt edge 4 to the third region 103 is greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0082] If the minimum distance L3 from the skirt edge 4 to the third region 103 is too small, the distance from the pad 2 to the skirt edge 4 will be too close. Since there are certain tolerances in the assembly process, the close distance from the pad 2 to the skirt edge 4 will easily cause the pad 2 to interfere with the convex 3, affecting the assembly and reducing the assembly yield of the battery.

[0083] If the minimum distance L3 from the skirt edge 4 to the third region 103 is too large, the distance between the pad 2 and the skirt edge 4 will be too far, resulting in a reduction in the contact area between the sleeve 1 and the pad 2. The sleeve 1 will not be able to effectively cover the pad 2, which will also reduce the probability of insulation between the positive and negative electrodes of the cylindrical battery and increase the risk of short circuit between the positive and negative electrodes.

[0084] In some embodiments, the minimum distance L4 from the skirt edge 4 to the third region 103 is 1.3 mm, and the ratio of L4 to R0 is 12.3%.

[0085] As shown in Figure 4, the minimum distance from the skirt edge 4 to the first region 101 is L10, and the ratio of L10 to R0 is greater than or equal to 20% and less than or equal to 35%.

[0086] If the ratio of L10 to R0 is too small, the amount of sleeve 1 used will increase, which will not only increase the cost and weight of the cylindrical battery and reduce the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0087] If the ratio of L10 to R0 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the negative terminal of the cylindrical battery by the sleeve 1.

[0088] The minimum distance L10 from the skirt edge 4 to the first region 101 is greater than or equal to 2mm and less than or equal to 4mm.

[0089] If the minimum distance L10 from the skirt 4 to the first region 101 is too small, the amount of sleeve 1 used will increase, which will not only increase the cost and weight of the cylindrical battery and reduce the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0090] If the minimum distance L10 from the skirt edge 4 to the first region 101 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the sleeve 1 on the negative terminal of the cylindrical battery.

[0091] In some embodiments, the minimum distance L10 from the skirt edge 4 to the first region 101 is 2.9 mm, and the ratio of L10 to R0 is 27.4%.

[0092] As shown in Figure 5, the negative terminal face of the cylindrical battery is a steel shell 5. The area of ​​the negative terminal face of the cylindrical battery that is not covered by the sleeve 1 is the area of ​​the steel shell 5 that is not covered by the sleeve 1. This is common knowledge in the field and will not be described in detail here.

[0093] As shown in Figure 6, the area on the negative terminal face of the cylindrical battery that is not covered by the sleeve 1 is the second region 102.

[0094] The area of ​​the second region 102 is S10, where the ratio of S10 to S0 is greater than or equal to 41% and less than or equal to 61%.

[0095] If the ratio of S10 to S0 is too small, the coverage area of ​​the sleeve 1 on the negative end of the cylindrical battery will be too large. This will not only increase the amount of sleeve 1 used, increasing the cost and weight of the cylindrical battery and reducing the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0096] If the ratio of S10 to S0 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the negative terminal of the cylindrical battery by the sleeve 1.

[0097] The outer diameter R3 of the second region 102 is greater than or equal to 6.5 mm and less than or equal to 8.5 mm.

[0098] If the outer diameter R3 of the second region 102 is too small, the coverage area of ​​the sleeve 1 on the negative end of the cylindrical battery will be too large. This will not only increase the amount of sleeve 1 used, increase the cost and weight of the cylindrical battery, and reduce the energy density of the battery, but also affect the aesthetics of the cylindrical battery.

[0099] If the outer diameter R3 of the second region 102 is too large, the coverage area of ​​the sleeve 1 on the negative terminal of the cylindrical battery will be too small. During the cyclic charging and discharging process, the cylindrical battery will inevitably generate heat, and the heat generation at the positive and negative terminals of the battery will be more severe. This will easily cause the sleeve 1 to shrink due to heat, further reducing the coverage area of ​​the sleeve 1 on the negative terminal, thus resulting in poor coverage of the sleeve 1 on the negative terminal of the cylindrical battery.

[0100] In some embodiments, the outer diameter R3 of the second region 102 is 7.58 mm, and the area S10 of the second region 102 is 180.5 mm². 2 The ratio of S10 to S0 is 51.3%.

[0101] Based on the above-described cylindrical battery encapsulation structure, this utility model also provides a cylindrical lithium-ion battery, including the above-described cylindrical battery encapsulation structure.

[0102] Through the description of several embodiments of the cylindrical battery coating structure and cylindrical lithium-ion battery of this utility model, it can be seen that the cylindrical battery coating structure and cylindrical lithium-ion battery embodiments of this utility model have at least one or more of the following advantages:

[0103] 1. The coverage area ratio of the sleeve 1 to the positive and negative terminals of the cylindrical battery is reasonable. By ensuring that the ratio of the area S1 of the first region 101 (the area covered by the sleeve 1 on the positive terminal end face of the cylindrical battery) to the radial cross-sectional area S0 of the cylindrical battery after the sleeve 1 is installed is between 40% and 60%, it can ensure effective coverage of the positive terminal by the sleeve 1, avoid the problem of poor coverage caused by heat generation during cyclic charging and discharging, and avoid increasing cost, weight, and affecting aesthetics due to excessive coverage area, as well as causing assembly interference problems; by ensuring that the second region 102 (the area covered by the sleeve 1 on the positive terminal end face of the cylindrical battery) is between 40% and 60%, it can ensure effective coverage of the positive terminal by the sleeve 1, avoid the problem of poor coverage caused by heat generation during cyclic charging and discharging, and avoid increasing cost, weight, affecting aesthetics, and causing assembly interference problems due to excessive coverage area; by ensuring that the coverage area of ​​the second region 102 (the area covered by the sleeve 1 on the positive terminal end face of the cylindrical battery) is between 40% and 60%, it can ensure effective coverage of the positive terminal by the sleeve 1, avoid the problem of poor coverage caused by heat generation during cyclic charging and discharging, and avoid increasing cost, weight, affecting aesthetics, and causing assembly interference problems due to excessive coverage area; The ratio of the area S10 to S0 of the negative terminal face of the battery not covered by the sleeve 1 is between 41% and 61%, which can avoid the problems of cost, weight, aesthetics and poor coverage caused by the sleeve 1 covering the negative terminal too large or too small. By making the ratio of the area S2 to S0 of the third region 103 (the area of ​​the pad 2 not covered by the sleeve 1) between 13% and 25%, the sleeve 1 can effectively cover the pad 2, improve the probability of positive and negative electrode insulation, reduce the risk of short circuit, and at the same time avoid interference between the pad 2 and the protrusion 3 affecting assembly.

[0104] 2. The film width of the sleeve 1 for the positive and negative terminals of the cylindrical battery is such that by making the film width of the sleeve 1 at the positive terminal of the cylindrical battery (the difference between the outer diameter R0 and the inner diameter R1 of the first region 101) between 2mm and 4mm, it can prevent the problem of poor coverage due to the small coverage area, and will not increase the cost, weight and affect the aesthetics due to the large coverage area.

[0105] 3. By making the outer diameter R3 of the second region 102 between 6.5mm and 8.5mm, a series of problems caused by the unreasonable coverage area of ​​the sleeve 1 on the negative end can be avoided; by making the width of the third region 103 between 0.8mm and 2.4mm, the effective coverage of the sleeve 1 on the pad 2 and the smooth assembly can be ensured.

[0106] 4. By ensuring that the ratio of the minimum distance L3 from the convex hull 3 to the third region 103 to R0 is between 3% and 12%, and L3 is between 0.4mm and 1.2mm, interference between the face pad 2 and the convex hull 3 can be prevented from affecting assembly, while ensuring effective coverage of the sleeve 1 over the face pad 2 and insulation between the positive and negative poles; by ensuring that the ratio of the minimum distance L4 from the skirt 4 to the third region 103 to R0 is between 5% and 20%, and L4 is between 0.5mm and 2mm, interference between the face pad 2 and the skirt 4 can be avoided from affecting assembly, and effective coverage of the sleeve 1 over the face pad 2 and insulation between the positive and negative poles can be ensured. By ensuring that the ratio of the minimum distance L10 from the skirt edge 4 to the first region 101 to R0 is between 20% and 35%, and L10 is between 2mm and 4mm, the amount of sleeve 1 used can be controlled, avoiding increased cost, weight, and aesthetic issues, while ensuring effective coverage of the negative end. By ensuring that the ratio of the minimum distance L11 from the convex bulge 3 to the first region 101 to R0 is between 16% and 28%, and L11 is between 1.4mm and 3.4mm, the amount of sleeve 1 used can be controlled, avoiding increased cost, weight, and aesthetic issues, while ensuring effective coverage of the negative end.

[0107] 5. By rationally designing the area, size, and distance ratio between each region, interference between the sleeve 1 and various components is effectively avoided, improving the battery assembly yield. At the same time, the positive and negative electrodes of the battery are insulated, reducing the risk of short circuits and ensuring the performance and safety of the battery.

[0108] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0109] The above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A cylindrical battery coating structure, characterized in that, include: A sleeve (1) is fitted around the outer periphery of a cylindrical battery. The two ends of the sleeve (1) along its length are corresponding to the positive and negative terminals of the cylindrical battery, and the two ends of the sleeve (1) cover the outer edge of the positive terminal face and the outer edge of the negative terminal face of the cylindrical battery. The radial cross-sectional area of ​​the cylindrical battery after the sleeve (1) is fitted is S0. The area of ​​the positive terminal face of the cylindrical battery covered by the sleeve (1) is a first region (101), and the area of ​​the first region (101) is S1. The area of ​​the negative terminal face of the cylindrical battery not covered by the sleeve (1) is a second region (102), and the area of ​​the second region (102) is S10. The ratio of S1 to S0 is greater than or equal to 40% and less than or equal to 60%, and the ratio of S10 to S0 is greater than or equal to 41% and less than or equal to 61%.

2. The cylindrical battery coating structure according to claim 1, characterized in that, The first region (101) is annular, and the difference between the outer diameter R0 and the inner diameter R1 of the first region (101) is greater than or equal to 2 mm and less than or equal to 4 mm.

3. The cylindrical battery coating structure according to claim 1, characterized in that, The cylindrical battery has a face pad (2) and a cap. The face pad (2) and the cap are located at the positive end of the cylindrical battery. The sleeve (1) is in contact with the side of the face pad (2) away from the inside of the cylindrical battery. The outer edge of the face pad is covered by the sleeve. The cap is located on the side away from the inside of the cylindrical battery. The outer edge of the cap is covered by the face pad (2). The area of ​​the face pad (2) not covered by the sleeve (1) is a third region (103). The area of ​​the third region (103) is S2. The ratio of S2 to S0 is greater than or equal to 13% and less than or equal to 25%.

4. The cylindrical battery coating structure according to claim 3, characterized in that, The difference between the inner diameter R1 of the first region (101) and the inner diameter R2 of the third region (103) is greater than or equal to 0.8 mm and less than or equal to 2.4 mm.

5. The cylindrical battery coating structure according to claim 3, characterized in that, The cap has a convex bulge (3) and a skirt (4). The convex bulge (3) is located on the outer periphery of the skirt (4) and protrudes in a direction away from the center of the skirt (4). The minimum distance from the convex bulge (3) to the third region (103) is L3. The ratio of L3 to R0 is greater than or equal to 3% and less than or equal to 12%.

6. The cylindrical battery coating structure according to claim 5, characterized in that, The minimum distance from the skirt edge (4) to the third region (103) is L4, and the ratio of L4 to RO is greater than or equal to 5% and less than or equal to 20%.

7. A cylindrical battery coating structure according to claim 5, characterized in that, The minimum distance from the skirt edge (4) to the first region (101) is L10, and the ratio of L10 to R0 is greater than or equal to 20% and less than or equal to 35%.

8. A cylindrical battery coating structure according to claim 5, characterized in that, The minimum distance from the convex hull (3) to the first region (101) is L11, and the ratio of L11 to R0 is greater than or equal to 16% and less than or equal to 28%.

9. A cylindrical battery coating structure according to claim 1, characterized in that, The outer diameter R3 of the second region (102) is greater than or equal to 6.5 mm and less than or equal to 8.5 mm.

10. A cylindrical lithium-ion battery, characterized in that, Includes the cylindrical battery pack structure as described in any one of claims 1-9.

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