Cover plate structure, battery and battery pack

The cover plate structure with a groove and angled sealing nail design addresses welding defects in cylindrical lithium-ion batteries by ensuring uniform gap formation and alignment, enhancing the sealing process.

JP7789141B2Active Publication Date: 2025-12-19HUIZHOU EVE POWER CO LTD
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Patent Information

Application Number
JP2024138359
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2023-08-23
Filing Date
2024-08-20
Publication Date
2025-12-19
Estimated Expiration
2044-08-20

AI Technical Summary

Technical Problem

Conventional sealing methods for cylindrical lithium-ion batteries suffer from welding defects such as warping and protrusions due to the inability to specify the placement position of the sealing nail within the pole post hole during the welding process.

Method used

A cover plate structure with a groove in the pole post and a sealing nail designed with specific included angles and dimensions to ensure proper alignment and support during welding, preventing warping and protrusions by allowing uniform gap formation.

Benefits of technology

The solution ensures uniform gap formation and proper alignment of the sealing nail, preventing welding defects and improving the overall quality of the seal.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a cover plate structure, a battery, and a battery pack, capable of avoiding a warp, a projection, and a welding failure.SOLUTION: A cover plate structure of the present invention includes: a cover plate; a pole column in which a concave groove 21 connected to the cover plate is provided, a flat surface positioned to an upper surface of the pole column defined as a first flat surface 22, a groove wall of the concave groove 21 containing at least a first surface segment 23, the first surface segment 23 connected to the first flat surface 22, and a narrow angle of the first surface segment 23 and the first flat surface 22 being θ2; and a seal peg provided into the concave groove 21, welded and connected to the pole column, a flat surface positioned on an upper surface of the seal peg defined as a second flat surface, a sidewall of the seal peg containing at least a first surface part, the first surface part connected to a second flat surface, and a narrow angle of the first and second surface parts being θ1, where θ1≥θ2 is satisfied.SELECTED DRAWING: Figure 4
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Description

[Technical Field]

[0001] The present invention relates to the technical field of batteries, and in particular to a cover plate structure, a battery, and a battery pack. [Background technology]

[0002] Lithium-ion batteries have the advantages of high energy density, fast charging and discharging, long cycle life, and no pollution, and are widely used in the fields of portable electronic devices, communications, energy storage, and electric vehicles.

[0003] One type of lithium-ion battery is a cylindrical battery, which includes a case, a winding core disposed within the case, and a cover plate for covering the case, on which poles are disposed. During the production process of cylindrical batteries, holes must be drilled in the poles to meet the process requirements for external penetration welding between the poles and the positive current collecting disks. After welding the poles and the positive current collecting disks, sealing nails are typically welded to the hole areas in the poles to ensure sealing and structural strength of the hole areas.

[0004] In conventional sealing methods, the placement position of the sealing nail within the pole post hole cannot be specified, which makes it easy for welding defects, such as warping or protrusions, to occur after welding. Summary of the Invention [Means for solving the problem]

[0005] In order to solve at least one of the problems existing in the above-mentioned prior art, according to one aspect of the present invention, there is provided a cover plate structure comprising: a cover plate; a polar post connected to the cover plate and having a groove formed therein, wherein the plane on which the upper surface of the polar post is located is defined as a first plane, the groove wall of the groove includes at least a first surface segment, the first surface segment is connected to the first plane, and the included angle between the first surface segment and the first plane is θ2; and a seal nail provided in the groove and welded to the polar post, wherein the plane on which the upper surface of the seal nail is located is defined as a second plane, the side wall of the seal nail includes at least a first surface portion, the first surface portion is connected to the second plane, and the included angle between the first surface portion and the second plane is θ1, and θ1≧θ2.

[0006] In this way, when welding the seal nail to the terminal post, the included angle θ1 between the first surface portion of the seal nail and the second flat surface is greater than the included angle θ2 between the first surface segment of the groove and the first flat surface. Therefore, when the seal nail is placed in the groove of the terminal post, the side walls of the seal nail can be supported by the groove walls of the groove, which can limit the placement position of the seal nail, allowing the seal nail to be adjusted to be placed flat in the groove, ensuring as uniform a gap as possible between the seal nail and the groove walls. In this embodiment, compared to a configuration in which the included angle θ1 between the first surface portion and the second flat surface is smaller than the included angle θ2 between the first surface segment of the groove and the first flat surface, warping, protrusions, poor welding, etc. of the seal nail can be avoided after placing it in the groove and welding.

[0007] In some embodiments, a groove wall of the recessed groove includes the first surface segment and a second surface segment that are connected, the second surface segment is spaced from the first plane, an included angle between an extension line of the second surface segment and the first plane is θ4, and θ2>θ4; The side wall of the sealing nail includes the first surface portion and the second surface portion, the first surface portion corresponds to the first surface segment, the second surface portion corresponds to the second surface segment, and the included angle between the extension line of the second surface portion and the second plane is θ3, where θ1>θ3 and θ4≧θ3.

[0008] In some embodiments, there is an arcuate transition between the first surface and the second surface.

[0009] In some embodiments, θ4>θ3.

[0010] In some embodiments, the outer diameter D1 of the sealing nail is in the range of 3 to 20 mm, the diameter D2 of the recessed groove is in the range of 3 to 30 mm, and D2≧D1.

[0011] In some embodiments, θ1>θ2 and D2>D1.

[0012] In some embodiments, the height H1 of the sealing nail ranges from 3 to 30 mm, and the height H2 of the recessed groove ranges from 3 to 30 mm.

[0013] According to another aspect of the present invention, there is provided a battery including a case, a winding core disposed within the case, and the above-described cover plate structure for covering the case.

[0014] In some embodiments, the outer diameter D3 of the case is in the range of 20 to 80 mm, and the total height H3 of the case and the cover plate is in the range of 80 to 160 mm.

[0015] According to yet another embodiment of the present invention, there is provided a battery pack including the battery described above. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a structural schematic diagram of a battery according to an embodiment of the present invention; [Figure 2] FIG. 2 is a cross-sectional schematic view of the battery in FIG. [Figure 3] FIG. 3 is an enlarged schematic view of a portion I in FIG. 2. [Figure 4] FIG. 4 is a schematic diagram showing the structure of the pole pillar in FIG. 3. [Figure 5]FIG. 4 is a schematic diagram of the structure of the seal nail in FIG. 3. [Figure 6] FIG. 10 is a schematic diagram of the fitting of a pole post and a seal nail in the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0017] For better understanding and implementation, the following clearly and completely describes the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention.

[0018] However, in the description of the present invention, the orientations or positional relationships indicated by terms such as "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" are based on the orientations or positional relationships shown in the drawings, and are merely for the convenience and simplification of the description of the present invention. They do not indicate or imply that the devices or elements shown must have a specific orientation or be configured and operated in a specific orientation, and therefore cannot be understood as limitations on the present invention.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting of the present invention.

[0020] The present invention will be described in more detail below with reference to the drawings.

[0021] Referring to Figure 6, the mating configuration between the terminal post 20 and the seal nail 30 in the cover plate 10 of the prior art is shown. The terminal post 20 is provided with a groove 21, and the seal nail 30 is disposed within the groove 21. The groove walls of the groove 21 are inclined at an angle α relative to the top surface of the terminal post 20, and the side walls of the seal nail 30 are inclined at an angle β relative to the top surface of the seal nail 30. In the prior art design, α > β, so when the seal nail 30 is placed in the groove 21 for welding, the inclination angle of the seal nail 30 is small, making it difficult to determine its position within the groove 21. As a result, the seal nail 30 cannot be placed flat within the groove 21 and is therefore inclined. Furthermore, the mating gap between the seal nail 30 and some areas of the groove 21 is too large, resulting in poor welding, such as warping or protrusions. Therefore, to improve the poor appearance of the seal nail 30 after welding into the terminal post 20, it is necessary to improve the mating configuration between the seal nail 30 and the groove 21 in the prior art.

[0022] 2 to 5, a cover plate structure 100 according to a first embodiment of the present invention includes a cover plate 10, a pole post 20, and a sealing nail 30. As shown in FIG.

[0023] 2 to 5, the polar post 20 is connected to the cover plate 10, and the polar post 20 is provided with a groove 21. The plane on which the upper surface of the polar post 20 is located is defined as a first plane 22. The groove wall of the groove 21 includes at least a first surface segment 23, which is connected to the first plane 22, and the included angle between the first surface segment 23 and the first plane 22 is θ2. The seal nail 30 is provided in the groove 21 and welded to the polar post 20, and the plane on which the upper surface of the seal nail 30 is located is defined as a second plane 31. The side wall of the seal nail 30 includes at least a first surface portion 32, which is connected to the second plane 31, and the included angle between the first surface portion 32 and the second plane 31 is θ1, where θ1≧θ2.

[0024] In the cover plate structure 100, when the seal nail 30 is welded to the terminal post 20, the included angle θ1 between the first surface portion 32 of the seal nail 30 and the second flat surface 31 is greater than the included angle θ2 between the first surface segment 23 of the groove 21 and the first flat surface 22. Therefore, when the seal nail 30 is placed in the groove 21 of the terminal post 20, the side walls of the seal nail 30 can be supported by the groove walls of the groove 21, which can limit the placement position of the seal nail 30. The seal nail 30 can be adjusted to be placed flat in the groove 21, ensuring as uniform a gap as possible between the seal nail 30 and the groove walls. Compared to a configuration in which the included angle θ1 between the first surface portion 32 and the second flat surface 31 is smaller than the included angle θ2 between the first surface segment 23 of the groove 21 and the first flat surface 22, this embodiment can avoid warping, protrusions, poor welding, etc. after the seal nail 30 is placed in the groove 21 and welded.

[0025] Here, in correspondence with the embodiment in which θ1 is set to ≧θ2, the outer diameter D1 of the seal nail 30 in this embodiment is in the range of 3 to 20 mm, and the diameter D2 of the groove 21 is in the range of 3 to 30 mm, with D2 ≧D1. For example, when θ1 is set to = θ2, the side wall of the seal nail 30 just contacts the groove wall of the groove 21, and both are loosely fitted. In this case, the gap is set to 0 and D2 can be set to = D1. For example, when the outer diameter of the seal nail 30 is 3 mm, the diameter of the groove 21 is also 3 mm. When θ1 is set to > θ2, in order to place the seal nail 30 in the groove 21, the outer diameter D1 of the seal nail 30 and the outer diameter D2 of the groove 21 must satisfy the condition that D2 is greater than D1. For example, when the diameter D1 of the seal nail 30 is 3 mm, the outer diameter D2 of the groove 21 can be 3.5 mm. In this way, the seal nail 30 with the larger inclination angle can be placed in the recessed groove 21, and the placement position in the recessed groove 21 can also be adjusted.

[0026] Furthermore, in order to facilitate the production of the sealing nail 30 and the opening of the groove 21, in this embodiment, θ1 is set to be greater than θ2 and D2 is set to be greater than D1. Therefore, when θ1 is set to be equal to θ2 and D2 is set to be equal to D1, θ1 and θ2 may not be equal due to production errors. Also, D2 may not be the same size as D1 due to production errors. Finally, when the sealing nail 30 is placed in the groove 21, the arrangement may become uneven. the law of nature Therefore, in this embodiment, by making θ1 > θ2 and D2 > D1, the sealing nail 30 can be placed in the groove 21 and supported by the groove wall of the groove 21, and the placement position of the sealing nail 30 can be adjusted within the groove wall of the groove 21, thereby achieving a good welding effect.

[0027] 3 and 4, in one embodiment of the present invention, in order to improve the fitting effect between the sealing nail 30 and the groove 21, the groove wall of the groove 21 in this embodiment includes a first surface segment 23 and a second surface segment 24 connected together, the second surface segment 24 is spaced apart from the first plane 22, and the included angle between the second surface segment 24 and the first plane 22 is θ4, where θ2>θ4, i.e., the included angle between the first surface segment 23 and the first plane 22 is greater than the included angle between the second surface segment 24 and the first plane 22.

[0028] The side wall of the sealing nail 30 includes a first surface portion 32 and a second surface portion 33. The first surface portion 32 corresponds to the first surface segment 23, and the second surface portion 33 corresponds to the second surface segment 24. The included angle between the second surface portion 33 and the second plane 31 is θ3, where θ1>θ3, i.e., the included angle between the first surface portion 32 and the second plane 31 is larger than the included angle between the second surface portion 24 and the second plane 31, and θ4≧θ3. That is, the groove wall of the recessed groove 21 in this embodiment is configured to include two portions, and correspondingly, the side wall of the sealing nail 30 also includes two portions. In this way, when the sealing nail 30 is placed in the groove 21, the sealing nail 30 can be supported by the groove wall of the groove 21, ensuring the fit between the sealing nail 30 and the groove wall of the groove 21, adjusting the gap between the sealing nail 30 and the groove wall of the groove 21, reducing the assembly gap between the two, and avoiding welding defects. In addition, by making the sealing nail 30 and the groove 21 into two inclined parts, the material of the sealing nail 30 can be saved and the volume of the sealing nail 30 can be reduced.

[0029] Specifically, in this embodiment, by setting θ4 to > θ3, when θ4 is set to = θ3, the produced seal nail 30 cannot achieve the standard of θ4 = θ3 due to production errors, and it is avoided that the seal nail 30 cannot be placed in the groove 21, for example, when θ4 < θ3.

[0030] Furthermore, in order to easily adjust the position of the seal nail 30 within the groove 21, an arc-shaped transition surface 34 is provided between the first surface 32 and the second surface 33. As can be seen, the arc-shaped transition surface 34 is located in contact with the groove wall of the groove 21, so that when adjusting the seal nail 30 within the groove 21, the arc-shaped transition surface 34 allows the seal nail 30 to easily move within the groove 21 to adjust its position within the groove 21. Furthermore, when adjusting the placement position of the seal nail 30, the seal nail 30 slides within the groove 21, thereby reducing the frictional force between the seal nail 30 and the groove wall of the groove 21 and preventing scratches on the groove 21 due to the sharp transition.

[0031] 4 and 5, in one embodiment of the present invention, the height H1 of the seal nail 30 is in the range of 3 to 30 mm, and the height H2 of the groove 21 is in the range of 3 to 30 mm. In one specific embodiment of the present invention, the height H1 of the seal nail 30 is smaller than the height H2 of the groove 21. In this way, after the seal nail 30 is placed in the groove 21, the seal nail 30 does not contact the bottom of the groove 21.

[0032] Here, in this embodiment, the fitting welding position between the seal nail 30 and the groove 21 is the outer ring surface of the seal nail 30 and the top of the groove 21, and the laser source acts on the seal nail 30 and the pole 20, melting the seal nail 30 and the pole 20 and connecting them together after cooling and solidifying.

[0033] 1 and 2, the second embodiment of the present invention further provides a battery 200, specifically, the battery 200 is a cylindrical battery 200, including a case 40, a winding core 50 and the cover plate 10 structure 100.

[0034] Here, the case 40 forms a storage space for storing the winding core 50, the winding core 50 is disposed within the case 40, and the cover plate structure 100 is used to cover the case 40, thus forming a cylindrical battery 200 after assembly.

[0035] Specifically, in this embodiment, the range of the outer diameter D3 of the case 40 is 20 to 80 mm, and the range of the total height H3 of the case 40 and the cover plate 10 is 80 to 160 mm, so that the appropriate dimensions of the case 40 and the overall height of the battery 200 can be selected according to the model number of the battery 200.

[0036] A third embodiment of the present invention further provides a battery pack, the battery pack including the battery described above.

[0037] The technical means disclosed in the aspects of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions consisting of any combination of the above technical features. It should be noted that those skilled in the art can make some improvements and refinements without departing from the principle of the present invention, and these improvements and refinements are also considered to be within the protection scope of the present invention. [Explanation of symbols]

[0038] 100 - cover plate structure, 10 - cover plate, 20 - pole, 21 - groove, 22 - first plane, 23 - first surface segment, 24 - second surface segment, 30 - sealing nail, 31 - second plane, 32 - first surface portion, 33 - second surface portion, 34 - arc transition surface, 200 - battery, 40 - case, 50 - winding core

Claims

1. A cover plate structure, A cover plate; A polar post connected to the cover plate and provided with a recessed groove, wherein a plane on which an upper surface of the polar post is located is defined as a first plane, a groove wall of the recessed groove includes at least a first surface segment, the first surface segment is connected to the first plane, and an included angle between the first surface segment and the first plane is θ 2 and A seal nail is provided in the groove and welded to the pole post, and a plane on which an upper surface of the seal nail is located is defined as a second plane, and a side wall of the seal nail includes at least a first surface portion, the first surface portion is connected to the second plane, and an included angle between the first surface portion and the second plane is θ 1 and a sealing nail, θ 1 ≧θ 2 and a groove wall of the groove includes the first surface segment and a second surface segment connected to each other, the second surface segment is spaced apart from the first plane, and an included angle between the plane on which the second surface segment is located and the first plane is θ 4; θ 2 >θ 4 , a side wall of the sealing nail including the first surface portion and a second surface portion, the first surface portion corresponding to the first surface segment, the second surface portion corresponding to the second surface segment, and an included angle between a plane on which the second surface portion is located and the second plane is θ 3; θ 1 >θ 3 , A cover plate structure characterized in that θ 4 >θ 3 .

2. The cover plate structure according to claim 1 , wherein the first surface portion and the second surface portion are connected by a circular arc transition surface.

3. A cover plate structure, A cover plate; a polar post connected to the cover plate and having a recessed groove, the plane on which the upper surface of the polar post is located being defined as a first plane, the groove wall of the recessed groove including at least a first surface segment, the first surface segment being connected to the first plane, and the included angle between the first surface segment and the first plane being θ 2; a seal nail provided in the groove and welded to the pole post, the plane on which the upper surface of the seal nail is located being defined as a second plane, the side wall of the seal nail including at least a first surface portion, the first surface portion being connected to the second plane, and the included angle between the first surface portion and the second plane being θ 1; The outer diameter D1 of the seal nail is in the range of 3 to 20 mm, the diameter D2 of the groove is in the range of 3 to 30 mm, and D2≧D1; θ 1 >θ 2 and D2>D1.

4. The cover plate structure according to claim 1, wherein the height H1 of the sealing nail is in the range of 3 to 30 mm, and the height H2 of the groove is in the range of 3 to 30 mm.

5. A battery, Case and a winding core provided in the case; and a cover plate structure according to any one of claims 1 to 4 for covering the case.

6. 6. The battery according to claim 5, wherein the outer diameter D3 of the case is in the range of 20 to 80 mm, and the total height H3 of the case and the cover plate is in the range of 80 to 160 mm.

7. A battery pack comprising the battery according to claim 6.

Citation Information

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