Single battery and battery pack

Abstract

The utility model discloses a single battery and a battery pack, and belongs to the technical field of batteries, the single battery comprises: a shell having an accommodating cavity and an opening communicating with the accommodating cavity; the electrode assembly is arranged in the accommodating cavity; the cover plate covers the opening, a mounting hole penetrating in the first direction is formed in the cover plate, and the first direction is the thickness direction of the cover plate; the pole comprises a body part and a riveting part, the body part is arranged in the mounting hole in a penetrating manner, and the riveting part is connected to one end, far away from the electrode assembly, of the body part; the first sealing piece is arranged on the side, away from the electrode assembly, of the cover plate and surrounds the periphery of the body part; according to the cover plate assembly, the pole, the first sealing piece and the cover plate are fixed together through the riveting part, on one hand, insulation between the first sealing piece and the cover plate can be kept, on the other hand, a riveting block is omitted, the number of parts of the cover plate assembly is reduced, procedures related to riveting block assembling are simplified, and the assembling efficiency of the cover plate assembly is improved.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a single cell battery and a battery pack. Background Technology

[0002] Secondary batteries are widely used as power batteries in electric vehicles and energy storage. The cover plate assembly of the secondary battery is welded to the battery casing to form a cavity isolated from the outside world. The internal current of the secondary battery is transported to the outside through the terminals in the cover plate assembly.

[0003] Traditional cover plate assemblies mainly consist of several parts, including a plain aluminum plate, riveting blocks, poles, upper plastic, lower plastic, and sealing rings. The large number of parts results in low assembly efficiency for cover plate assemblies. Utility Model Content

[0004] The purpose of this utility model is to provide a single battery cell to solve the technical problem of low assembly efficiency of current cover plate components; another purpose of this application is to provide a battery pack.

[0005] Technical solution: The single-cell battery described in the embodiments of this application includes:

[0006] A housing having a receiving cavity and an opening communicating with the receiving cavity;

[0007] The electrode assembly is disposed within the receiving cavity;

[0008] A cover plate is provided over the opening, and the cover plate has a mounting hole extending through a first direction, which is the thickness direction of the cover plate.

[0009] An electrode post includes a body portion and a riveting portion, the body portion passing through the mounting hole, and the riveting portion being connected to the end of the body portion away from the electrode assembly;

[0010] A first sealing element is disposed on the side of the cover plate away from the electrode assembly and is disposed around the outer periphery of the body portion. The riveting portion is configured to press the first sealing element onto the cover plate to fix the electrode post, the first sealing element and the cover plate together.

[0011] In some embodiments, the first seal includes a first sealing section and a second sealing section, the first sealing section being sandwiched between the riveted portion and the cover plate, and at least partially disposed within the mounting hole;

[0012] The second sealing section is connected to the first sealing section and fits against the outer periphery of the riveted part.

[0013] In some embodiments, in the first direction, the surface of the body portion facing away from the electrode assembly is located on the side of the second sealing section away from the cover plate, and the distance between the surface of the body portion facing away from the electrode assembly and the surface of the second sealing section facing away from the cover plate is H1mm, satisfying: H1≥0.25.

[0014] In some embodiments, the cover plate includes a main body and a protrusion, the main body covering the opening;

[0015] The protrusion is connected to the main body and surrounds the mounting hole. At least a portion of the protrusion protrudes from the main body in a direction away from the electrode assembly. At least a portion of the first seal is sandwiched between the riveting portion and the protrusion.

[0016] The main body includes a first surface disposed opposite to the electrode assembly along the first direction, and the protrusion includes a second surface disposed opposite to the electrode assembly along the first direction. In the first direction, the distance between the first surface and the second surface is H2mm, satisfying: 0.8≤H2≤1.2.

[0017] In some embodiments, the thickness of the protrusion along the first direction is H3mm, satisfying: 1≤H3≤2.

[0018] In some embodiments, the electrode post further includes a limiting portion connected to one end of the body portion near the electrode assembly, the limiting portion including a first limiting surface;

[0019] The single battery cell further includes a second sealing member, which is disposed around the outer periphery of the limiting portion and connected to the cover plate. The second sealing member includes a second limiting surface, which cooperates with the first limiting surface to restrict the rotation of the electrode post.

[0020] In some embodiments, the limiting portion includes a plurality of first limiting surfaces, which are spaced apart around the outer periphery of the limiting portion, and the second sealing member includes a plurality of second limiting surfaces, each of which corresponds to one of the first limiting surfaces.

[0021] In some embodiments, at least a portion of the second seal is sandwiched between the main body and the limiting portion. In the first direction, the surface of the limiting portion facing away from the electrode assembly is located between the protrusion and the side of the main body near the electrode assembly. The distance between the surface of the limiting portion facing away from the electrode assembly and the surface of the main body facing the electrode assembly is H4mm, satisfying: H4≥0.35.

[0022] In some embodiments, the second seal includes a first portion, a second portion, and a third portion, wherein the first portion is disposed on the side of the body portion near the electrode assembly and is connected to the body portion;

[0023] The second part is sandwiched between the main body and the limiting part and is connected to the first part, and the second limiting surface is disposed on the side of the second part facing the limiting part;

[0024] The third part is sandwiched between the protrusion and the limiting part, and is connected to the second part.

[0025] Accordingly, the battery pack described in this application embodiment includes the aforementioned single battery cell.

[0026] Beneficial effects: In the embodiments of this application, the single battery cell fixes the terminal post, the first seal and the cover plate together by the riveting part. On the one hand, the insulation between the first seal and the cover plate can be maintained by the first seal. On the other hand, the riveting block is eliminated, which reduces the number of parts of the cover plate assembly and simplifies the assembly process related to the riveting block, which helps to improve the assembly efficiency of the cover plate assembly. The pressing of the riveting part on the first seal plays a role in pre-fixing the first seal, which facilitates the further connection of the first seal in the future.

[0027] The battery pack of this application embodiment includes the above-described single battery cell, and therefore can have all the technical features and beneficial effects of the above-described single battery cell. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A cross-sectional view of a single battery cell provided in an embodiment of this application;

[0030] Figure 2 A schematic diagram showing the relative positions of the pole post, the first seal, and the third seal as provided in an embodiment of this application;

[0031] Figure 3 A cross-sectional view of the cover plate provided in an embodiment of this application;

[0032] Figure 4 A perspective view of a single battery cell provided in an embodiment of this application;

[0033] Figure 5 A perspective view of the pole provided in the embodiments of this application;

[0034] Figure 6 A perspective view of the second seal provided in an embodiment of this application;

[0035] Reference numerals: 1. Housing; 11. Receiving cavity; 2. Electrode assembly; 3. Cover plate; 31. Main body; 311. First surface; 32. Protrusion; 321. Second surface; 33. Mounting hole; 4. Electrode post; 41. Body; 42. Riveting part; 43. Limiting part; 431. First limiting surface; 5. First seal; 51. First sealing section; 52. Second sealing section; 6. Second seal; 61. First part; 62. Second part; 621. Second limiting surface; 63. Third part. Detailed Implementation

[0036] The technical solutions of the embodiments of this application 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 application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0037] In the description of this application, it should be understood that the terms "height," "thickness," "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. In the description of this application, "a plurality of" means two or more, and "at least one" can mean one, two, or more, unless otherwise expressly specified.

[0038] It should also be noted that in the accompanying drawings of the embodiments of this application, the arrow marked with X represents the first direction X. The first direction X is introduced to more clearly illustrate the structure and relative positional relationship of each component in the single cell. In practical applications, the first direction X may change depending on the arrangement of the single cell.

[0039] Please combine them together Figure 1 , Figure 2 and Figure 3The single-cell battery of this application embodiment includes a housing 1, an electrode assembly 2, a cover plate 3, a terminal post 4, and a first sealing member 5. The housing 1 has a receiving cavity 11 and an opening communicating with the receiving cavity 11 for inserting battery components. The electrode assembly 2 is disposed in the receiving cavity 11 and includes tabs and electrode groups, wherein the electrode group includes a separator and at least two electrode sheets. The separator and at least two electrode sheets are stacked and wound in a preset order, and the tabs are connected to the electrode sheets. The cover plate 3 covers the opening and is connected to the housing 1. The cover plate 3 has a mounting hole 33 extending along a first direction X, where the first direction X is the thickness direction of the cover plate 3. The terminal post 4 includes a body portion 41 and a riveting portion 42. The body portion 41 passes through the mounting hole 33, and the riveting portion 42 is connected to the end of the body portion 41 away from the electrode assembly 2 and is disposed around the outer periphery of the body portion 41.

[0040] The first sealing element 5 is disposed on the side of the cover plate 3 away from the electrode assembly 2 and surrounds the outer periphery of the body part 41. The riveting part 42 is configured to press the first sealing element 5 onto the cover plate 3, thereby fixing the electrode post 4, the first sealing element 5, and the cover plate 3 together. The riveting part 42 is initially disposed along the first direction X. During assembly, the riveting part 42 is riveted outward by a riveting device to press the first sealing element 5 tightly onto the cover plate 3, thereby fixing the electrode post 4, the first sealing element 5, and the cover plate 3 together. Since the riveting block in the cover plate 3 assembly is removed, the number of parts composed of the cover plate 3 assembly is reduced, and the assembly process corresponding to the riveting block is also simplified, thereby reducing the overall assembly time and improving assembly efficiency.

[0041] Please combine them together Figure 1 and Figure 2 In some embodiments, the first sealing element 5 is connected to the cover plate 3. For example, the first sealing element 5 can be fixed to the cover plate 3 by bonding or hot melting to further stabilize the structure of the first sealing element 5 and seal the gap between the first sealing element 5 and the cover plate 3. Since the first sealing element 5 is pre-fixed by the riveting part 42, the relative displacement of the first sealing element 5 in subsequent assembly steps is restricted, which provides convenience for the assembly of the first sealing element 5 to a certain extent and helps to improve assembly efficiency.

[0042] Please combine them together Figure 2 and Figure 3In some embodiments, the first sealing element 5 includes a first sealing section 51 and a second sealing section 52. The first sealing section 51 is sandwiched between the riveting portion 42 and the cover plate 3, and is at least partially disposed within the mounting hole 33. The first sealing section 51 separates the riveting portion 42 from the cover plate 3, and also separates the body portion 41 from the hole wall of the mounting hole 33, maintaining insulation between the pole post 4 and the cover plate 3. The second sealing section 52 is connected to the first sealing section 51 and fits against the outer periphery of the riveting portion 42. The second sealing section 52 is integrally formed with the first sealing section 51, and is opposite to the outer periphery of the riveting portion 42, restricting the displacement of the pole post 4 in its own radial direction.

[0043] Please combine them together Figure 2 and Figure 3 In some embodiments, in the first direction X, the surface of the body portion 41 facing away from the electrode assembly 2 is located on the side of the second sealing section 52 away from the cover plate 3. The distance between the surface of the body portion 41 facing away from the electrode assembly 2 and the surface of the second sealing section 52 facing away from the cover plate 3 is H1 mm, satisfying: H1 ≥ 0.25. Specifically, H1 can be any value among 0.25, 0.27, 0.29, and 0.31, or a range between any two values. The upper end surface of the body portion 41 is higher than the upper end surface of the second sealing section 52, so that there is a certain gap between the tooling and the upper plastic when the pole post 4 is riveted, so as to reduce the possibility of the riveting tooling contacting the upper plastic and damaging the upper plastic.

[0044] Please combine them together Figure 2 and Figure 3 In some embodiments, the cover plate 3 includes a main body 31 and a protrusion 32. The main body 31 covers the opening and is connected to the housing 1. The protrusion 32 is connected to the main body 31 and forms a mounting hole 33 around it. At least a portion of the protrusion 32 protrudes from the main body 31 in a direction away from the electrode assembly 2. At least a portion of the first sealing member 5 is sandwiched between the riveting portion 42 and the protrusion 32. The protrusion 32 is integrally formed with the main body 31 and can be processed by stamping to ensure mutual sealing performance and connection strength.

[0045] The main body 31 includes a first surface 311 disposed opposite to the electrode assembly 2 along the first direction X, and a protrusion 32 includes a second surface 321 disposed opposite to the electrode assembly 2 along the first direction X. The distance between the first surface 311 and the second surface 321 in the first direction X is H2 mm, satisfying: 0.8 ≤ H2 ≤ 1.2. Specifically, H2 can be any value among 0.8, 0.9, 1.0, 1.1, and 1.2, or a range between any two values. The portion of the protrusion 32 between the first surface 311 and the second surface 321 is the portion of the protrusion 32 that protrudes from the main body 31 in the direction away from the electrode assembly 2. The protrusion 32 causes the cover plate 3 to extend along the first direction X in a localized location, forming support for the first sealing section 51 to meet the design requirements of different heights of the electrode post 4.

[0046] Please combine them together Figure 2 and Figure 3 In some embodiments, the thickness of the protrusion 32 along the first direction X is H3mm, satisfying: 1≤H3≤2. Specifically, H3 can be any value among 1, 1.2, 1.4, 1.6, 1.8, and 2, or a range between any two values. Limiting the thickness of the protrusion 32 helps to ensure the structural stability and structural strength after it is riveted to the pole post 4.

[0047] Please combine them together Figure 2 , Figure 4 and Figure 5 In some embodiments, the terminal post 4 further includes a limiting portion 43, which is connected to one end of the body portion 41 near the electrode assembly 2. The limiting portion 43 includes a first limiting surface 431, which is planar and disposed on the outer peripheral surface of the limiting portion 43. The single cell also includes a second sealing member 6, which is disposed around the outer periphery of the limiting portion 43 and connected to the cover plate 3. The second sealing member 6 includes a second limiting surface 621, which is planar and cooperates with the first limiting surface 431 to restrict the rotation of the terminal post 4. There is a certain gap between the second limiting surface 621 and the first limiting surface 431 to facilitate the assembly of the terminal post 4 and the second sealing member 6. At the same time, the distance of this gap is less than the radius of the rotation trajectory of the limiting portion 43, which ensures the convenience of assembly and maintains a tight connection between the limiting portion 43 and the second sealing member 6 to increase the safety performance of the battery.

[0048] During charging, the battery expands, generating expansion force. Additionally, under vehicle operating conditions, vibrations and bumps generate thrust and torque between the batteries. Under the influence of these expansion and thrust forces, the terminal post 4 is prone to rotation during use. When the terminal post 4 is subjected to a torsional force, the first limiting surface 431 is abutted by the second limiting surface 621, restricting the rotation of the limiting part 43. This limits the rotation of the terminal post 4, helps to secure the connection between the terminal post 4 and its associated components, and ensures the battery's safety performance.

[0049] Please combine them together Figure 2 , Figures 4 to 6 In some embodiments, the limiting part 43 includes a plurality of first limiting surfaces 431, which are spaced apart around the outer periphery of the limiting part 43. The second sealing member 6 includes a plurality of second limiting surfaces 621, each of which corresponds to one first limiting surface 431. The cooperation of multiple sets of first limiting surfaces 431 and second limiting surfaces 621 can provide more limiting points and increase the contact area between the limiting part 43 and the second sealing member 6. On the one hand, this can make the torsional force on the pole post 4 more evenly distributed, reducing the possibility of excessive local pressure on the second sealing member 6. On the other hand, it can enhance the limiting effect on the pole post 4.

[0050] Please refer to Figure 2 In some embodiments, at least a portion of the second sealing member 6 is sandwiched between the main body portion 31 and the limiting portion 43. In the first direction X, the surface of the limiting portion 43 facing away from the electrode assembly 2 is located between the protrusion 32 and the side of the main body portion 31 near the electrode assembly 2. The distance between the surface of the limiting portion 43 facing away from the electrode assembly 2 and the surface of the main body portion 31 facing the electrode assembly 2 is H4mm, satisfying: H4≥0.35. Specifically, H4 can be any value among 0.35, 0.36, 0.37, and 0.38, or a range between any two values. In the first direction X, the upper end face of the limiting part 43 is higher than the lower end face of the main body 31. At the same time, since part of the second sealing member 6 is sandwiched between the main body 31 and the limiting part 43, that is, the part of the second sealing member 6 corresponding to the second limiting surface 621 is sandwiched between the main body 31 and the limiting part 43, when the second limiting surface 621 is squeezed by the limiting part 43, the end of the main body 31 near the limiting part 43 abuts against the second sealing member 6, restricting the outward expansion of the second sealing member 6, thereby maintaining the relative positional relationship between the second limiting surface 621 and the first limiting surface 431, which is beneficial to improving the effect of the second sealing member 6 in restricting the rotation of the pole post 4, and achieving the purpose of stabilizing the connection of the pole post 4.

[0051] Please refer to Figure 2In some embodiments, the second seal 6 includes a first portion 61, a second portion 62, and a third portion 63. The first portion 61 is disposed on the side of the main body 31 near the electrode assembly 2 and is connected to the main body 31. The second portion 62 is sandwiched between the main body 31 and the limiting portion 43 and is connected to the first portion 61. A second limiting surface 621 is disposed on the side of the second portion 62 facing the limiting portion 43. The third portion 63 is sandwiched between the protrusion 32 and the limiting portion 43 and is connected to the second portion 62. The third portion 63, the second portion 62, and the first portion 61 are integrally formed. The second portion 62 is blocked by the main body 31, so that the second limiting surface 621 can maintain a stable relative position with the first limiting surface 431, while also separating the limiting portion 43 from the main body 31. The third portion 63 serves to separate the upper end surface of the limiting portion 43 from the lower end surface of the protrusion 32, and also cooperates with the second portion 62 to define the relative position of the electrode post 4 in its axial and radial directions.

[0052] Accordingly, the battery pack provided in this application includes the single cell of the above embodiment. Therefore, the battery pack can have all the technical features and beneficial effects of the single cell, which will not be repeated here.

[0053] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0054] The single-cell battery and battery pack provided in the embodiments of this application have been described in detail above, and specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A single cell, characterized by, The single battery comprises a shell, an electrode assembly, a cover plate, a pole post, and a first sealing member. The shell has a receiving cavity and an opening communicating with the receiving cavity. The electrode assembly is arranged in the receiving cavity. The cover plate covers the opening and is provided with a mounting hole penetrating in a first direction. The pole post comprises a body portion and a riveting portion. The body portion penetrates the mounting hole.

2. The cell according to claim 1, wherein The riveting portion is connected to one end of the body portion away from the electrode assembly. The first sealing member is arranged on a side of the cover plate away from the electrode assembly and surrounds an outer periphery of the body portion.

3. The cell according to claim 2, wherein The riveting portion is configured to press the first sealing member against the cover plate to fix the pole post, the first sealing member, and the cover plate.

4. The cell according to claim 1, wherein The first sealing member comprises a first sealing segment and a second sealing segment. The first sealing segment is arranged between the riveting portion and the cover plate and at least partially in the mounting hole. The second sealing segment is connected to the first sealing segment and is in contact with an outer periphery of the riveting portion.

5. The cell according to claim 4, wherein In the first direction, a surface of the body portion away from the electrode assembly is located on a side of the second sealing segment away from the cover plate.

6. The cell according to claim 4, wherein A distance between the surface of the body portion away from the electrode assembly and a surface of the second sealing segment away from the cover plate is H1 mm, and H1≥0.

25. The cover plate comprises a main body portion and a protruding portion.

7. The cell according to claim 6, wherein The main body portion covers the opening. The protruding portion is connected to the main body portion and surrounds the mounting hole. At least a part of the protruding portion protrudes from the main body portion in a direction away from the electrode assembly. At least a part of the first sealing member is arranged between the riveting portion and the protruding portion. The main body portion comprises a first surface arranged in the first direction away from the electrode assembly. The protruding portion comprises a second surface arranged in the first direction away from the electrode assembly. In the first direction, a distance between the first surface and the second surface is H2 mm, and 0.8≤H2≤1.

2. A thickness of the protruding portion in the first direction is H3 mm, and 1≤H3≤2. The pole post further comprises a limiting portion. The limiting portion is connected to one end of the body portion close to the electrode assembly. The limiting portion comprises a first limiting surface. The single battery further comprises a second sealing member. The second sealing member surrounds an outer periphery of the limiting portion and is connected to the cover plate. The second sealing member comprises a second limiting surface. The second limiting surface cooperates with the first limiting surface to limit rotation of the pole post. The limiting portion comprises a plurality of first limiting surfaces. The second sealing member comprises a plurality of second limiting surfaces. Each second limiting surface corresponds to one first limiting surface.

8. The cell according to claim 6, wherein At least part of the second sealing member is clamped between the main body portion and the limiting portion, and a surface of the limiting portion facing away from the electrode assembly is located between the protruding portion and a side of the main body portion close to the electrode assembly in the first direction, and a distance between the surface of the limiting portion facing away from the electrode assembly and a surface of the main body portion facing toward the electrode assembly is H4 mm, and H4≥0.35 is satisfied.

9. The cell according to claim 8, wherein The second sealing member includes a first portion, a second portion, and a third portion, the first portion is arranged on a side of the main body portion close to the electrode assembly and connected with the main body portion; The second portion is clamped between the main body portion and the limiting portion and connected with the first portion, and the second limiting surface is arranged on a side of the second portion facing toward the limiting portion; The third portion is clamped between the protruding portion and the limiting portion and connected with the second portion.

10. A battery pack, characterized by, A single battery including the single battery as claimed in any one of claims 1 to 9.

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