Cover plate structure, battery, and battery pack

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

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, rapid 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 in the case, and a cover plate for covering the case, on which a pole is disposed. In the production process of the cylindrical battery, in order to meet the process requirements for performing external penetration welding on the pole and the positive current collecting disk, it is necessary to open a hole in the pole. After welding the pole and the positive current collecting disk, in order to ensure the sealing property and structural strength of the opening area, it is generally necessary to weld a sealing nail to the opening area in the pole to realize the sealing property and structural strength of the opening area.

[0004] In the conventional sealing method, the placement position of the sealing nail within the pole post hole cannot be specified, so welding defects such as warping and protrusions are likely 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 having a groove connected to the cover plate, 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 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 θ2; and a seal nail provided in the groove and welded to the polar post, wherein a plane on which an upper surface of the seal nail is located is defined as a second plane, 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 θ1, and θ1≧θ2.

[0006] In this way, when the seal nail and the pole are welded, the included angle θ1 between the first surface portion of the seal nail and the second plane is greater than the included angle θ2 between the first surface segment of the groove and the first plane, so that when the seal nail is placed in the groove of the pole, the side wall of the seal nail can be supported by the groove wall of the groove, the groove wall of the groove can limit the placement position of the seal nail, the seal nail can be adjusted to be placed flat in the groove, and the gap between the seal nail and the groove wall can be ensured as uniform as possible. In this embodiment, compared to a form in which the included angle θ1 between the first surface portion and the second plane is smaller than the included angle θ2 between the first surface segment of the groove and the first plane, warping, protrusions, welding defects, etc. of the seal nail can be avoided after the seal nail is placed in the groove and welded.

[0007] In some embodiments, a groove wall of the groove includes the first surface segment and a second surface segment that are connected to each other, the second surface segment is spaced from the first plane, and 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 a 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 an extension line of the second surface portion and the second plane is θ3, 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 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 is in the range of 3 to 30 mm, and the height H2 of the recessed groove is in the range of 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 comprising the battery described above. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram of the structure of a battery according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a schematic cross-sectional view of the battery in FIG. [Diagram 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. [Diagram 5]FIG. 4 is a schematic diagram showing the structure of the seal nail in FIG. 3. [Figure 6] FIG. 1 is a schematic diagram of a terminal post and a seal nail fitting in the prior art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In order to be better understood and implemented, the technical solutions of the embodiments of the present invention are clearly and completely described hereinafter 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", "inside", "outside", etc. 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, and do not indicate or imply that the devices or elements shown must have a specific orientation or be constructed 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 now be described in more detail with reference to the drawings.

[0021] 6, the fitting form of the pole post 20 and the seal nail 30 in the cover plate 10 in the prior art is shown. The pole post 20 is provided with a groove 21, and the seal nail 30 is provided in the groove 21. The groove wall of the groove 21 has an inclination angle α with respect to the upper surface of the pole post 20, and the side wall of the seal nail 30 has an inclination angle β with respect to the upper 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 and welded, the inclination angle of the seal nail 30 is small and the placement position in the groove 21 cannot be specified, so it cannot be placed flat in the groove 21 and is in an inclined state. In addition, the fitting gap between the seal nail 30 and some areas of the groove 21 is too large, so that after welding, there will be problems such as poor welding, such as warping and protrusions. Therefore, in order to improve the poor appearance of the seal nail 30 after welding in the pole post 20, it is necessary to improve the fitting form of 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 seal nail 30. As shown in FIG.

[0023] 2 to 5, the pole 20 is connected to the cover plate 10, the pole 20 is provided with a groove 21, the plane on which the upper surface of the pole 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, the first surface segment 23 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 pole 20, 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, the first surface portion 32 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 above cover plate structure 100, when the seal nail 30 and the pole 20 are welded, the included angle θ1 between the first surface portion 32 and the second plane 31 of the seal nail 30 is greater than the included angle θ2 between the first surface segment 23 and the first plane 22 of the groove 21, so that when the seal nail 30 is placed in the groove 21 of the pole 20, the side wall of the seal nail 30 can be supported by the groove wall of the groove 21, the groove wall of the groove 21 can limit the placement position of the seal nail 30, and the seal nail 30 can be adjusted to be placed flat in the groove 21, so that the gap between the seal nail 30 and the groove wall can be ensured as uniform as possible. In this embodiment, compared with a form in which the included angle θ1 between the first surface portion 32 and the second plane 31 is smaller than the included angle θ2 between the first surface segment 23 and the first plane 22 of the groove 21, warping, protrusions, welding defects, etc. can be avoided after the seal nail 30 is placed in the groove 21 and welded.

[0025] Here, in response to the form in which θ1 is set to ≧θ2, the range of the outer diameter D1 of the seal nail 30 in this embodiment is 3 to 20 mm, and the range of the diameter D2 of the groove 21 is 3 to 30 mm, and 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 which case the gap can be 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, if the seal nail 30 needs to be placed in the groove 21, the outer diameter D1 of the seal nail 30 and the outer diameter D2 of the groove 21 need to satisfy that D2 is larger than D1. For example, when the diameter D1 of the seal nail 30 is set to 3 mm, the outer diameter D2 of the groove 21 can be set to 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 seal 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. In this case, 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 seal nail 30 is placed in the groove 21, the arrangement may become uneven. the law of nature Finally, it is possible to avoid the occurrence of warping or protrusions after welding. Therefore, in this embodiment, by making θ1 > θ2 and D2 > D1, it is possible to ensure that the seal 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 seal 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 to each other, the second surface segment 24 is separated 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, that is, 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 seal 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, 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, θ1>θ3, that is, 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 groove 21 in this embodiment is configured to include two portions, and correspondingly, the side wall of the seal nail 30 also includes two portions. In this way, when the seal nail 30 is placed in the groove 21, the seal nail 30 can be supported by the groove wall of the groove 21, the fit between the seal nail 30 and the groove wall of the groove 21 can be ensured, the gap between the seal nail 30 and the groove wall of the groove 21 can be adjusted, the assembly gap between the two can be reduced, and poor welding can be avoided; and by making the seal nail 30 and the groove 21 into two inclined parts, the material of the seal nail 30 can be saved and the volume of the seal nail 30 can be reduced.

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

[0030] Furthermore, in order to easily adjust the position of the seal nail 30 in the groove 21, there is an arcuate transition surface 34 between the first surface portion 32 and the second surface portion 33. As can be seen, the arcuate transition surface 34 is in contact with the groove wall of the groove 21, so that when the seal nail 30 is adjusted in the groove 21, the arcuate transition surface 34 makes it easy to move the seal nail 30 in the groove 21 to adjust the position of the seal nail 30 in the groove 21. In addition, when adjusting the placement position of the seal nail 30, the seal nail 30 moves in a sliding manner in the groove 21, thereby reducing the frictional force between the seal nail 30 and the groove wall of the groove 21, and avoiding scratches on the groove 21 due to the sharp transition manner.

[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 post 20, melting the seal nail 30 and the pole post 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, which includes a case 40, a winding core 50 and the above-mentioned 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 being assembled.

[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 depending on 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-seal 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 pole pole connected to the cover plate and provided with a recessed groove, a plane on which an upper surface of the pole pole 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, 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 an included angle between the first surface portion and the second plane is θ １ and a seal nail, θ １ ≧θ ２ A cover plate structure comprising:

2. The groove wall of the groove includes the first surface segment and the second surface segment that are connected to each other, and the second surface segment is spaced 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 and θ ２ >θ ４ and The side wall of the seal nail includes the first surface portion and a second surface portion, the first surface portion corresponds to the first surface segment, the second surface portion corresponds 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 and θ １ >θ ３ and θ ４ ≧θ ３ 2. The cover plate structure according to claim 1, wherein:

3. 3. The cover plate structure of claim 2, wherein the first surface and the second surface are connected by a circular arc transition surface.

4. θ ４ >θ ３ 3. The cover plate structure according to claim 2, wherein:

5. The cover plate structure according to claim 1, characterized in that 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.

6. θ １ >θ ２ 6. The cover plate structure according to claim 5, wherein D2>D1.

7. 2. 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.

8. A battery, Case and A winding core provided in the case; and a cover plate structure according to any one of claims 1 to 7 for covering the case.

9. 9. The battery of claim 8, wherein an outer diameter D3 of the case is in the range of 20 to 80 mm, and a total height H3 of the case and the cover plate is in the range of 80 to 160 mm.

10. A battery pack comprising the battery according to claim 8.

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