Pole group packaging structure and single battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a pole group packaging structure and a single battery, the pole group packaging structure comprises a shell and a cover plate, the shell is provided with an opening, the distance between the inner walls of the two opposite sides of the shell is F, the cover plate comprises a cover plate body and a boss, the cover plate body covers the opening in a sealing manner, and the boss is arranged on the cover plate body. The boss protrudes out of the side, facing the shell, of the cover plate body, the boss is located in the shell, the distance between the two opposite side walls of the boss is D, and (F-D) is larger than or equal to 0 and smaller than or equal to 0.45 mm, so that the boss can stretch into the shell, the side walls of the boss can be tightly attached to the inner wall of the shell, the boss can be smoothly installed in the shell, and the service life of the boss is prolonged. And the sealing effect between the cover plate and the shell can be greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an electrode packing structure and a single battery cell. Background Technology

[0002] A single battery cell typically includes an electrode assembly, a battery casing, and a cover plate. The electrode posts are located inside the battery casing, and the cover plate is placed over the opening of the battery casing to create a sealed space inside the battery casing.

[0003] In the existing technology, the opening between the cover plate and the battery case is usually welded and fixed. The seal between the cover plate and the battery case opening is achieved only by the weld between the two. The reliability of the seal between the two is low. When the individual battery generates gas during charging and discharging, the high-pressure gas inside the battery case will form shear force at the weld, causing the weld to crack, which in turn leads to leakage of the individual battery, causing the individual battery to fail or even cause a safety accident.

[0004] Therefore, there is an urgent need to propose an electrode packing structure and a single cell to solve the above-mentioned technical problems. Utility Model Content

[0005] The first objective of this invention is to provide a pole group packaging structure that not only allows the boss to be easily installed into the housing, but also significantly improves the sealing effect between the cover plate and the housing.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] The electrode group packaging structure includes:

[0008] The shell has an opening, and the distance between the inner walls of the opposite sides of the shell is F;

[0009] The cover plate includes a cover plate body and a boss. The cover plate body is sealed at the opening. The boss protrudes from the side of the cover plate body facing the housing and is located inside the housing. The distance between the two opposite side walls of the boss is D, 0≤(FD)≤0.45mm, so that the boss can extend into the housing and the side wall of the boss can be tightly attached to the inner wall of the housing.

[0010] Optionally, the side of the boss away from the cover plate body is transitioned to the side wall of the boss by a chamfer.

[0011] Optionally, the chamfer angle is β, where 40°≤β≤55°.

[0012] Optionally, the length of the chamfer is C, and the distance between the opposite outer walls of the shell is G, where C ≥ (GF) / 2.

[0013] Optionally, the length of the chamfer is C, where 0.2mm ≤ C ≤ 1.0mm.

[0014] Optionally, the length of the chamfer is C, and the thickness of the boss is B, (BC)≥0.55mm.

[0015] Optionally, the distance between the two opposite outer walls of the shell is G, and the distance between the two opposite side walls of the cover plate body is E, where G = E.

[0016] Optionally, the thickness of the cover plate body is A, the thickness of the boss is B, P = B / (A+B), and 50% ≤ P ≤ 80%.

[0017] The second objective of this invention is to provide a single-cell battery with a high degree of sealing between the cover plate and the casing.

[0018] To achieve this objective, the present invention adopts the following technical solution:

[0019] A single cell includes an electrode assembly and the aforementioned electrode assembly encapsulation structure, with the electrode assembly disposed within the housing.

[0020] The beneficial effects of this utility model are:

[0021] The electrode assembly packaging structure provided by this utility model has a cover plate body sealingly covering the opening of the housing to form a first layer of seal between the cover plate and the housing. The cover plate body has a protrusion on the side facing the battery housing. The distance between the inner walls of the opposite sides of the housing is F, and the distance between the two side walls of the protrusion is D, where 0≤(FD)≤0.45mm. This structure can not only smoothly insert the protrusion into the housing, but also make the side wall of the protrusion fit tightly against the inner wall of the housing to form a second layer of seal between the cover plate and the housing. It can be seen that this electrode assembly packaging structure has a two-layer sealing structure, which greatly improves the sealing effect between the cover plate and the housing. Attached Figure Description

[0022] Figure 1 This is an exploded view of the electrode group packaging structure provided by this utility model;

[0023] Figure 2 This is a partially enlarged schematic diagram of the electrode group packaging structure provided by this utility model. Figure 1 ;

[0024] Figure 3 This is a partially enlarged structural schematic diagram of the cover plate provided by this utility model;

[0025] Figure 4 This is a partially enlarged schematic diagram of the electrode group packaging structure provided by this utility model. Figure 2 ;

[0026] Figure 5 This is a partially enlarged schematic diagram of the electrode group packaging structure provided by this utility model. Figure 3.

[0027] In the picture:

[0028] 100, shell; 110, opening; 200, cover plate; 210, cover plate body; 220, boss; 230, chamfer. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0030] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between 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.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0033] This embodiment provides a pole group packaging structure that not only allows the boss to be easily installed into the housing, but also significantly improves the sealing effect between the cover plate and the housing.

[0034] Specifically, such as Figures 1 to 5 As shown, the electrode assembly packaging structure includes a housing 100 and a cover plate 200. The housing 100 has an opening 110, and the distance between the inner walls of the opposite sides of the housing 100 is F. The cover plate 200 includes a cover plate body 210 and a boss 220. The cover plate body 210 is sealed and covered at the opening 110. The boss 220 protrudes from the side of the cover plate body 210 facing the housing 100 and is located inside the housing 100. The distance between the two opposite side walls of the boss 220 is D, where 0 ≤ (FD) ≤ 0.45 mm. For example, the value of (FD) can be 0.1 mm, 0.15 mm, 0.2 mm, 0.4 mm, or 0.45 mm, etc., so that the boss 220 can extend into the housing 100 and the side wall of the boss 220 can be tightly attached to the inner wall of the housing 100.

[0035] Based on the above design, the cover plate body 210 is sealed at the opening 110 of the housing 100 to form the first layer of seal between the cover plate 200 and the housing 100. The cover plate body 210 has a boss 220 on the side facing the battery case. The distance between the inner walls of the opposite sides of the housing 100 is F, and the distance between the two side walls of the boss 220 is D, 0≤(FD)≤0.45mm. This design allows the boss 220 to be installed into the housing 100 relatively smoothly, and also allows the side wall of the boss 220 to be tightly attached to the inner wall of the housing 100 to form the second layer of seal between the cover plate 200 and the housing 100. It can be seen that the electrode group packaging structure has a two-layer sealing structure, which greatly improves the sealing effect between the cover plate 200 and the housing 100.

[0036] Furthermore, the cover plate body 210 is welded to the housing 100 so that the cover plate body 210 is sealed and covered at the opening 110 of the housing 100.

[0037] Preferably, 0 ≤ (FD) ≤ 0.2 mm, which reduces the welding defect rate between the cover plate body 210 and the housing 100 while ensuring that the side wall of the boss 220 is tightly attached to the inner wall of the housing 100.

[0038] Optionally, such as Figures 1 to 5 As shown, the thickness of the cover plate body 210 is A, the thickness of the boss 220 is B, P = B / (A+B), and 50% ≤ P ≤ 80%. For example, P can be 50%, 66%, 70%, 75%, or 80%, etc., with 66% ≤ P ≤ 75% being preferred. In this embodiment, the value of P is set between 50% and 80%. While minimizing the space occupied by the boss 220 within the housing 100, it ensures that the sidewall of the boss 220 has a sufficiently large area to be tightly attached to the inner wall of the housing 100, thus guaranteeing the reliability of the second layer of sealing. This further improves the sealing effect between the cover plate 200 and the housing 100 without occupying too much space within the housing 100.

[0039] Optionally, such as Figures 1 to 5 As shown, the distance between the two opposite outer walls of the housing 100 is G, and the distance between the two opposite side walls of the cover plate body 210 is E, where G = E. This ensures that the cover plate body 210 and the opening 110 of the housing 100 have sufficient overlap area, improving the welding yield at the opening 110 of the cover plate body 210 and the housing 100, thereby improving the reliability of the sealing connection at the opening 110 of the cover plate body 210 and the housing 100. Furthermore, it allows the side wall of the cover plate body 210 to be flush with the outer wall of the housing 100, resulting in better structural consistency between the cover plate 200 and the housing 100.

[0040] Optionally, such as Figures 1 to 5 As shown, the side of the boss 220 away from the cover plate body 210 is transitioned to the side wall of the boss 220 by a chamfer 230. During the process of fastening the cover plate body 210 to the opening 110 of the housing 100, the chamfer 230 can guide the cover plate body 210, making it easier to install the boss 220 into the housing 100. At the same time, it can also avoid the problem of the opening 110 of the housing 100 being bumped or crushed by the cover plate 200 or other production equipment due to the positioning deviation between the cover plate 200 and the housing 100.

[0041] Furthermore, such as Figures 1 to 5 As shown, the length of the chamfer 230 is C, and (BC) ≥ 0.55 mm. For example, (BC) can be 0.55 mm, 0.75 mm, 0.8 mm, or 0.95 mm, etc., with (BC) ≥ 0.75 mm being preferred. This ensures that the sidewall of the boss 220, with the chamfer 230, has a sufficiently large area to fit tightly against the inner wall of the housing 100, thereby guaranteeing the reliability of the second layer of sealing and providing strong protection for the sealing between the cover plate 200 and the housing 100. In addition, increasing the value of (BC) can improve the welding yield between the cover plate body 210 and the housing 100.

[0042] Optionally, such as Figures 1 to 5 As shown, the distance between the opposite outer walls of the housing 100 is G, the wall thickness of the housing 100 is H, H=(GF) / 2, C≥H, and the length of the chamfer 230 is extended as much as possible to improve the reliability of the guiding function of the chamfer 230.

[0043] Optionally, 0.2mm≤C≤1.0mm. For example, C can be 0.2mm, 0.3mm, 0.4mm, 0.5mm or 1.0mm, etc., with 0.3mm≤C≤0.5mm being preferred, to ensure that the chamfer 230 has a good guiding effect and reduce the probability of the opening 110 of the housing 100 being bumped or crushed.

[0044] Optionally, such as Figures 1 to 5 As shown, the angle of the chamfer 230 is β, 40°≤β≤55°. For example, β can be 40°, 45°, 48°, 50° or 55°, etc., with 45°≤β≤50° being preferred, in order to improve the guiding effect of the chamfer 230 and also to ensure that the side wall of the boss 220 has a sufficiently large area to fit tightly against the inner wall of the housing 100, thus ensuring the sealing between the cover plate 200 and the housing 100.

[0045] It should be noted that the electrode packing structure provided in this embodiment can be applied to single cells of various shapes, such as rectangular, square, and cylindrical cells. When the single cell is rectangular, such as... Figures 1 to 5 As shown, both the cover plate body 210 and the boss 220 are rectangular. The aforementioned E includes e1 and e2, where e1 is the length direction of the cover plate body 210. Figure 1 The distance between two opposite sidewalls in the x-direction of the cover plate body 210, e2 is the width direction of the cover plate body 210. Figure 1 The distance between two opposite sidewalls in the y-direction of the shell 100 is defined as follows: D includes d1 and d2, where d1 is the distance between two opposite sidewalls of the boss 220 in the x-direction, and d2 is the distance between two opposite sidewalls of the boss 220 in the y-direction; G includes g1 and g2, where g1 is the distance between two opposite outer walls of the shell 100 in the x-direction, and g2 is the distance between two opposite outer walls of the shell 100 in the y-direction; F includes f1 and f2, where f1 is the distance between two opposite inner walls of the shell 100 in the x-direction, and f2 is the distance between two opposite inner walls of the shell 100 in the y-direction. The value 0 ≤ (FD) ≤ 0.45 mm means: 0 ≤ (f1 - d1) ≤ 0.45 mm, and 0 ≤ (f2 - d2) ≤ 0.45 mm. The value G = E means g1 = e1 and g2 = e2. The above H includes h1 and h2, where h1 = (g1 - f1) / 2, h2 = (g2 - f2) / 2, and C ≥ H means C ≥ h1 and C ≥ h2. Typically, h1 = h2. When the single cell is square, e1 = e2, d1 = d2, g1 = g2, and f1 = f2. When the single cell is cylindrical, G refers to the outer diameter of the housing 100, and F refers to the inner diameter of the housing 100. Therefore, in this embodiment, the distance between two opposite sidewalls of the cover plate body 210 in any direction is E, the distance between two opposite sidewalls of the boss 220 in any direction is D, the distance between the two opposite outer walls of the housing 100 in any direction is G, and the distance between the two opposite inner walls of the housing 100 in any direction is F.

[0046] In this embodiment, as Figures 1 to 5As shown, the thickness A of the cover plate body 210 refers to its dimension in the z-direction, the thickness B of the boss 220 refers to its dimension in the z-direction, and the length C of the chamfer 230 refers to its dimension in the z-direction. The total thickness of the cover plate 200 is (A+B), where 1.5mm ≤ (A+B) ≤ 3.0mm. For example, (A+B) can be 1.5mm, 2.0mm, 2.5mm, or 3.0mm, etc. 0.5mm ≤ A ≤ 0.75mm. For example, A can be 0.5mm, 0.6mm, 0.7mm, or 0.75mm, etc. 0.75 ≤ B ≤ 2.25mm. For example, B can be 0.75mm, 1.0mm, 2.0mm, or 2.25mm, etc.

[0047] The technical solution provided in this embodiment involves fastening the cover plate body 210 to the opening 110 of the housing 100, and welding the cover plate body 210 to the housing 100. This allows for a good sealing and fixing effect between the cover plate 200 and the housing 100, while also improving the welding yield of the cover plate body 210 and the housing 100. Several sets of comparative data are provided below to verify the above technical effects.

[0048] Verification 1

[0049]

[0050] Therefore, when 0.3mm≤C≤0.5mm and 40°≤β≤55°, after the cover plate body 210 and the shell 100 are fastened together, the probability of the opening 110 of the shell 100 being bumped or crushed is significantly reduced.

[0051] Verification 2

[0052]

[0053]

[0054] As can be seen from Comparative Examples 11 to 14, the proportion of poor welding between the cover plate body 210 and the housing 100 decreases as the (BC) value increases. In particular, when (BC) reaches 0.75 mm or more, the proportion of poor welding between the cover plate body 210 and the housing 100 can be maintained below 0.041% (i.e., the welding yield is normal). When (BC) is below 0.75 mm, the proportion of poor welding between the cover plate body 210 and the housing 100 reaches 0.185% or more (i.e., the welding yield is abnormal).

[0055] As can be seen from Comparative Examples 15 to 20, when the fit between the boss 220 and the housing 100 is too loose, i.e., when the value of (FD) is too large, or when the fit between the boss 220 and the housing 100 is too tight, i.e. when the value of (FD) is negative, it will affect the insertion of the boss 220 into the housing 100, and the welding seal failure rate between the cover plate body 210 and the housing 100 will increase significantly.

[0056] This embodiment also provides a single battery cell, which includes an electrode assembly and the aforementioned electrode assembly encapsulation structure. The electrode assembly is disposed within the housing 100. The single battery cell pack adopts the aforementioned electrode assembly encapsulation structure. Therefore, the sealing performance between the cover plate 200 and the housing 100 of the single battery cell is relatively high.

[0057] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A polarity group packaging structure, characterized in that, include: A housing (100) having an opening (110) and a distance F between the inner walls of opposite sides of the housing (100); A cover plate (200) includes a cover plate body (210) and a boss (220). The cover plate body (210) seals the opening (110). The boss (220) protrudes from the side of the cover plate body (210) facing the housing (100) and is located inside the housing (100). The distance between the two opposite sidewalls of the boss (220) is D, 0≤(FD)≤0.45mm, so that the boss (220) can extend into the housing (100) and the sidewall of the boss (220) can be tightly attached to the inner wall of the housing (100).

2. The electrode assembly packaging structure according to claim 1, characterized in that, The side of the boss (220) facing away from the cover plate body (210) is transitioned to the side wall of the boss (220) by a chamfer (230).

3. The electrode group packaging structure according to claim 2, characterized in that, The angle of the chamfer (230) is β, where 40°≤β≤55°.

4. The electrode assembly packaging structure according to claim 2, characterized in that, The length of the chamfer (230) is C, and the distance between the opposite outer walls of the shell (100) is G, where C≥(GF) / 2.

5. The electrode assembly packaging structure according to claim 2, characterized in that, The length of the chamfer (230) is C, where 0.2mm ≤ C ≤ 1.0mm.

6. The electrode group packaging structure according to claim 2, characterized in that, The length of the chamfer (230) is C, and the thickness of the boss (220) is B, (BC) ≥ 0.55 mm.

7. The electrode group packaging structure according to any one of claims 1-6, characterized in that, The distance between the two opposite outer walls of the housing (100) is G, and the distance between the two opposite side walls of the cover plate body (210) is E, where G = E.

8. The electrode group packaging structure according to any one of claims 1-6, characterized in that, The thickness of the cover plate body (210) is A, the thickness of the boss (220) is B, P = B / (A+B), and 50% ≤ P ≤ 80%.

9. A single-cell battery, characterized in that, Includes an electrode assembly and an electrode assembly packaging structure as described in any one of claims 1-8, wherein the electrode assembly is disposed within the housing (100).

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