Secondary lithium battery top cover capable of reducing welding power

Abstract

The utility model provides a secondary lithium battery top cover capable of reducing welding power, which is characterized in that first accommodating holes for accommodating poles are formed in two ends of an aluminum sheet, and first annular grooves are formed around the first accommodating holes; second containing holes are formed in the two ends of the lower plastic, and a first clamping ring protrudes around the edges of the second containing holes. Third accommodating holes are formed in the positions, corresponding to the first accommodating holes, of the positive electrode connecting piece and the negative electrode connecting piece, and a circle of second clamping ring protrudes around the edges of the third accommodating holes; each of the positive pole and the negative pole comprises a copper column, a connecting aluminum sheet, a first step and a second step, the first clamping ring is clamped with the first accommodating hole, the second clamping ring is clamped with the second accommodating hole, the first step penetrates through the first accommodating hole, the first step is clamped with the second accommodating hole, and the second step is clamped with the third accommodating hole. And the second step of the pole is clamped with the third accommodating hole of the connecting piece and then is welded, so that the problems of melting, cracking, deformation and poor air tightness of the upper plastic caused by direct welding can be avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of new energy battery top covers, and particularly relates to a secondary lithium battery top cover capable of reducing welding power. Background Art

[0002] When welding the connectors of traditional secondary lithium battery top cover structures, especially the negative electrode connectors, the welding power is high, which can easily cause the upper plastic to melt, crack, deform, and deteriorate the airtightness. At the same time, the equipment investment cost is high. Utility Model Content

[0003] In order to solve the problems existing in the prior art, the utility model provides a secondary lithium battery top cover that can reduce welding power. The second step of the pole is snap-fitted with the third receiving hole of the connecting plate. The method of snap-fitting first and then welding is adopted to reduce welding power and reduce the problems of melting, cracking, deformation, and deterioration of airtightness of the upper plastic caused by high-power direct welding. At the same time, due to the lower welding power, the welding cost is also reduced.

[0004] In order to achieve the above purpose, the technical solutions adopted by this utility model are as follows:

[0005] A secondary lithium battery top cover capable of reducing welding power comprises a positive electrode connecting piece, a negative electrode connecting piece, a lower plastic, a plain aluminum sheet, a ring bracket, a positive electrode column, and a negative electrode column, which are sequentially connected from bottom to top.

[0006] The two ends of the aluminum sheet are provided with first receiving holes for receiving the poles, and a first annular groove is provided around the first receiving holes;

[0007] The lower plastic has second receiving holes at both ends corresponding to the first receiving holes, and a first clamping ring protrudes around the edge of the second receiving hole;

[0008] A third receiving hole is formed on the positive electrode connecting piece and the negative electrode connecting piece at a position corresponding to the first receiving hole, and a second clamping ring protrudes around the edge of the third receiving hole;

[0009] Each of the positive and negative electrode posts includes a copper post, an aluminum connecting sheet, a first step, and a second step. The first snap ring engages with the first receiving hole, the second snap ring engages with the second receiving hole, the first step passes through the first receiving hole, the first step engages with the second receiving hole, and the second step engages with the third receiving hole. The shape of the third receiving hole is adapted to the shape of the second step and is not limited to a circle, but changes with the shape of the second step.

[0010] Based on the above technical solutions, the present invention can also be improved as follows.

[0011] Furthermore, the above-mentioned secondary lithium battery top cover capable of reducing welding power has a plurality of first protrusions connected around the first annular groove on one side of the plain aluminum sheet facing the annular bracket, and a first groove is opened at a position corresponding to the first protrusion on the edge of the annular bracket, and the first protrusion and the first groove are matched in a concave-convex manner.

[0012] Furthermore, the above-mentioned secondary lithium battery top cover capable of reducing welding power has a plurality of second protrusions connected around the first clamping ring, and a plurality of second grooves are opened on the side of the plain aluminum sheet facing away from the annular bracket at positions corresponding to the second protrusions, and the second grooves are matched with the second protrusions in a concave-convex manner.

[0013] Furthermore, in the above-mentioned secondary lithium battery top cover capable of reducing welding power, the positive electrode connecting plate and the negative electrode connecting plate both include a first connecting portion and a second connecting portion, the first connecting portion is narrower than the second connecting portion, the first connecting portion is provided with a third accommodating hole, and a second clamping ring protrudes around the edge of the third accommodating hole, and the connecting aluminum sheet sits in the first annular groove.

[0014] Furthermore, in the aforementioned secondary lithium battery top cover capable of reducing welding power, the first groove is in a superior arc shape, and the opening is located on a side away from the center of the annular bracket.

[0015] Furthermore, the above-mentioned secondary lithium battery top cover capable of reducing welding power further includes a sealing ring. The positive electrode column and the negative electrode column are both sleeved with a sealing ring, and the side of the sealing ring close to the plain aluminum sheet is closely attached to the first annular groove.

[0016] Furthermore, in the above-mentioned secondary lithium battery top cover capable of reducing welding power, an explosion-proof hole is opened on the plain aluminum sheet, an explosion-proof valve is installed in the explosion-proof hole, and an explosion-proof valve protective film is connected to the top of the explosion-proof valve.

[0017] Furthermore, the above-mentioned secondary lithium battery top cover capable of reducing welding power also includes an aluminum nail, the second connecting portion is provided with a makeshift groove for making way for the aluminum nail, the plain aluminum sheet is provided with a first aluminum nail hole, the lower plastic is provided with a second aluminum nail hole, and the aluminum nail is threadedly connected to the first aluminum nail hole and the second aluminum nail hole.

[0018] Furthermore, in the above-mentioned secondary lithium battery top cover capable of reducing welding power, the side of the positive electrode column is connected with the positive electrode upper plastic around a circle, and the side of the negative electrode column is connected with the negative electrode upper plastic around a circle.

[0019] Furthermore, in the aforementioned secondary lithium battery top cover capable of reducing welding power, a sealing aluminum sheet is connected between the aluminum nail and the second aluminum nail hole.

[0020] Compared with the prior art, the technical solution of the utility model has the following beneficial technical effects:

[0021] The second step of the pole is clamped with the third receiving hole of the connecting piece and then welded, which can avoid the problems of melting, cracking, deformation and poor airtightness of the upper plastic caused by direct welding.

[0022] The aluminum sheet and the annular bracket adopt a concave-convex matching scheme similar to riveting, which is first matched with the concave and convex and then welded. The welding power is low and the cost of laser welding is reduced.

[0023] The lower plastic and the smooth aluminum sheet are matched in concave and convex manner. The concave and convex manner are matched first and then welded, which further reduces the welding power and reduces the cost of laser welding.

[0024] The superior arc-shaped first groove provides a certain degree of freedom during assembly, making it easier to adjust and align the position, thereby improving assembly efficiency. At the same time, it can better adapt to material deformation during environmental changes such as thermal expansion and contraction, and reduce stress caused by temperature changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the explosion structure of a secondary lithium battery top cover capable of reducing welding power provided by an embodiment of the utility model;

[0026] Figure 2 A perspective structural diagram of a secondary lithium battery top cover capable of reducing welding power provided by an embodiment of the present utility model;

[0027] Figure 3 for Figure 2 AA section view in the figure;

[0028] Figure 4 A schematic diagram of the structure of the light aluminum sheet and related structures provided in an embodiment of the present utility model from a top view;

[0029] Figure 5 A schematic diagram of the structure of the light aluminum sheet and related structures provided in an embodiment of the present utility model from an upward perspective;

[0030] Figure 6 A schematic diagram of the structure of the lower plastic and related structures provided in an embodiment of the present utility model from an upward perspective;

[0031] Figure 7 A schematic top view of the lower plastic and related structures provided in an embodiment of the present utility model;

[0032] Figure 8 A schematic diagram of the structure of the lower plastic and related structures provided in an embodiment of the present utility model from a top view;

[0033] Figure 9 A schematic diagram of the three-dimensional structure of the plastic on the positive electrode provided by an embodiment of the utility model;

[0034] Figure 10A schematic diagram of the three-dimensional structure of the annular bracket provided in an embodiment of the present utility model;

[0035] Figure 11 A schematic diagram of the three-dimensional structure of the annular bracket provided by an embodiment of the present utility model from another perspective;

[0036] Figure 12 A schematic top view of the positive electrode connecting piece provided in an embodiment of the present invention;

[0037] Figure 13 A schematic diagram of the three-dimensional structure of the positive electrode column provided in an embodiment of the present invention from a top view;

[0038] Figure 14 A schematic diagram of the three-dimensional structure of the positive electrode column provided by an embodiment of the utility model from an upward perspective.

[0039] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0040] 1. Plastic on the positive electrode; 2. Ring bracket; 21. First groove; 3. Positive pole; 31. Copper pillar; 32. Connecting aluminum sheet; 33. First step; 34. Second step; 4. Sealing ring; 5. Plain aluminum sheet; 51. First receiving hole; 52. First ring groove; 53. First bump; 54. Second groove; 55. First aluminum nail hole; 6. Lower plastic; 61. Second receiving hole; 62. First snap ring; 63. Second bump; 64. Second aluminum nail hole; 7. Positive connecting piece; 71. First connecting part; 72. Second connecting part; 73. Third receiving hole; 74. Second snap ring; 75. Make way groove; 8. Plastic on the negative electrode; 9. Negative pole; 10. Negative connecting piece; 11. Sealing aluminum sheet; 12. Explosion-proof valve; 13. Explosion-proof valve protective film. DETAILED DESCRIPTION

[0041] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0043] It will be understood that spatial relational terms such as "under," "beneath," "below," "under," "above," "above," etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It will be understood that in addition to the orientations shown in the figures, spatial relational terms also include different orientations of the device in use and operation. For example, if the device in the drawings is turned over, the element or feature described as "under" or "beneath" or "beneath" the other elements will be oriented as "above" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. In addition, the device may also include alternative orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0044] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In the following embodiments, "connection" should be understood as "electrical connection", "communication connection", etc., if the connected circuits, modules, units, etc. can transmit electrical signals or data to each other.

[0045] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

[0046] Example 1

[0047] To address the problem in the prior art of secondary lithium battery top covers that high welding power can easily cause the upper plastic to melt, crack, deform, and deteriorate in airtightness when welding connectors, especially the negative electrode connector, the present invention provides a secondary lithium battery top cover that reduces welding power. The top cover comprises a lower plastic 6, a plain aluminum sheet 5, and an annular bracket 2, connected sequentially from bottom to top. The plain aluminum sheet 5 and the annular bracket 2 have a concave-convex fit. Specifically, the plain aluminum sheet 5 has first receiving holes 51 at both ends for accommodating the terminal, a first annular groove 52 is formed around the first receiving hole 51, and a plurality of first protrusions 53 are connected to the side of the plain aluminum sheet 5 facing the annular bracket 2 around the first annular groove 52. The edge of the annular bracket 2 has first grooves 21 formed at positions corresponding to the first protrusions 53, and the first protrusions 53 and the first grooves 21 have a tight concave-convex fit. The plain aluminum sheet 5 and the annular bracket 2 adopt a concave-convex fit similar to riveting, with the concave-convex fit first and then laser welding, which can reduce welding power and reduce laser welding costs.

[0048] In this embodiment, based on the above embodiment, a further improvement is made, in which the first groove 21 is a major arc shape, with its opening located on the side away from the center of the annular bracket 2. A major arc shape is an arc larger than a semicircle. The major arc shape of the first groove 21 provides a certain degree of freedom during assembly, making position adjustment and alignment easier, improving assembly efficiency. It can also better adapt to material deformation during environmental changes such as thermal expansion and contraction, reducing stress caused by temperature changes.

[0049] In this embodiment, further improvements are made based on the above embodiment, and further include a lower plastic 6, wherein the lower plastic 6 has second accommodating holes 61 corresponding to the first accommodating holes 51 at both ends, a first clamping ring 62 protruding around the edge of the second accommodating hole 61, and a plurality of second protrusions 63 connected around the first clamping ring 62. The side of the bare aluminum sheet 5 facing away from the annular bracket 2 is provided with a plurality of second grooves 54 at positions corresponding to the second protrusions 63, and the second grooves 54 are tightly fitted with the second protrusions 63. The diameter of the second protrusion 63 is larger than the diameter of the first protrusion 53. The lower plastic 6 and the bare aluminum sheet 5 are matched with each other in a concave-convex manner. The concave-convex matching is performed first and then laser welding is performed, which can reduce the welding power and reduce the cost of laser welding.

[0050] In this embodiment, further improvements are made based on the above embodiment, and the positive electrode column 3, the negative electrode column 9, the positive connecting piece 7, the negative connecting piece 10, and the aluminum nail are also included. The positive connecting piece 7 and the negative connecting piece 10 both include a first connecting portion 71 and a second connecting portion 72. The first connecting portion 71 is narrower than the second connecting portion 72. The first connecting portion 71 is provided with a third accommodating hole 73, and a second clamping ring 74 protrudes around the edge of the third accommodating hole 73; the second connecting portion 72 is provided with a makeshift groove 75 for making way for the aluminum nail.

[0051] In this embodiment, based on the above embodiment, further improvements are made. The positive electrode post 3 and the negative electrode post 9 each include a copper post 31, a connecting aluminum sheet 32, a first step 33, and a second step 34. The connecting aluminum sheet 32 is seated in the first annular groove 52. The first snap ring 62 snaps into the first receiving hole 51, and the second snap ring 74 snaps into the second receiving hole 61. The first step 33 passes through the first receiving hole 51, snaps into the second receiving hole 61, and snaps into the second step 34 snaps into the third receiving hole 73. The shape of the third receiving hole 73 adapts to the shape of the second step 34 and is not limited to a circular shape; it changes with the shape of the second step 34. The second step of the post is snapped into the third receiving hole of the connecting sheet before welding, avoiding the problems of melting, cracking, deformation, and poor airtightness of the upper plastic that can be caused by direct welding. This sequential snap connection also improves the fit between different components. It also reduces welding power and lowers laser welding costs.

[0052] In this embodiment, based on the above embodiment, further improvements are made, and a sealing ring 4 is further included. The positive electrode column 3 and the negative electrode column 9 are both sleeved with a sealing ring 4, and the side of the sealing ring close to the plain aluminum sheet 5 is in close contact with the first annular groove 52.

[0053] This embodiment further improves upon the above embodiment by providing an explosion-proof hole in the aluminum sheet 5. An explosion-proof valve 12 is installed within the hole, and a protective film 13 is attached to the top of the valve 12. In the event of an internal battery abnormality, such as high temperature or combustion, the valve 12 ruptures to release exhaust, preventing battery explosion. The protective film provides daily protection for the valve 12. The provision of an explosion-proof hole and the installation of the valve 12 improve battery safety.

[0054] In this embodiment, based on the above embodiment, further improvements are made. A first aluminum nail hole 55 is opened on the plain aluminum sheet 5, and a second aluminum nail hole 64 is opened on the lower plastic 6. Aluminum nails are threadedly connected to the first aluminum nail hole 55 and the second aluminum nail hole 64.

[0055] In this embodiment, based on the above embodiment, further improvements are made. The positive electrode pole 3 is connected to the positive electrode upper plastic 1 around its side, and the negative electrode pole 9 is connected to the negative electrode upper plastic 8 around its side.

[0056] In this embodiment, a further improvement is made based on the above embodiment, in which a sealing aluminum sheet 11 is connected between the aluminum nail and the second aluminum nail hole 64. Connecting the sealing aluminum sheet can help conduct current more efficiently within the battery, reduce resistance, and improve battery performance; it can also enhance the structural stability of the battery, keep internal components fixed, and prevent displacement or damage during use; the sealing aluminum sheet helps prevent leakage of electrolyte within the battery, ensuring the safety and stability of the battery; and the sealing performance of the sealing aluminum sheet can help protect internal materials, reduce the risk of corrosion, and thus extend the service life of the battery.

[0057] By snapping together, the laser welding power for the connecting piece and the pole of the battery top cover is significantly lower than that required by the traditional structure, which not only reduces the welding cost, but also prevents problems such as cracking and deformation of the upper plastic caused by the excessive power required for laser welding of the traditional structure, thereby achieving the purpose of improving the performance reliability of the top cover and reducing manufacturing costs.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A secondary lithium battery top cover capable of reducing welding power, comprising a positive electrode connecting piece (7), a negative electrode connecting piece (10), a lower plastic (6), a plain aluminum sheet (5), an annular bracket (2), a positive electrode column (3), and a negative electrode column (9) connected in sequence from bottom to top, characterized in that: The two ends of the bare aluminum sheet (5) are provided with first receiving holes (51) for receiving the poles, and a first annular groove (52) is provided around the first receiving hole (51); The lower plastic (6) has second receiving holes (61) at both ends corresponding to the first receiving holes (51), and a first clamping ring (62) protrudes around the edge of the second receiving hole (61); A third receiving hole (73) is formed on the positive electrode connecting piece (7) and the negative electrode connecting piece (10) at a position corresponding to the first receiving hole (51), and a second clamping ring (74) protrudes around the edge of the third receiving hole (73); The positive electrode column (3) and the negative electrode column (9) both comprise a copper column (31), a connecting aluminum sheet (32), a first step (33), and a second step (34); the first clamping ring (62) is clamped with the first accommodating hole (51); the second clamping ring (74) is clamped with the second accommodating hole (61); the first step (33) passes through the first accommodating hole (51); the first step (33) is clamped with the second accommodating hole (61); and the second step (34) is clamped with the third accommodating hole (73).

2. A secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: A plurality of first protrusions (53) are connected to one side of the light aluminum sheet (5) facing the annular bracket (2) around the first annular groove (52). A first groove (21) is formed at a position on the edge of the annular bracket (2) corresponding to the first protrusions (53). The first protrusions (53) and the first grooves (21) are matched in a concave-convex manner.

3. The secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: A plurality of second protrusions (63) are connected around the first clamping ring (62), and a plurality of second grooves (54) are formed on a side of the light aluminum sheet (5) facing away from the annular bracket (2) at positions corresponding to the second protrusions (63). The second grooves (54) and the second protrusions (63) are matched in a concave-convex manner.

4. The secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: The positive electrode connecting piece (7) and the negative electrode connecting piece (10) both comprise a first connecting portion (71) and a second connecting portion (72), wherein the first connecting portion (71) is narrower than the second connecting portion (72), and the first connecting portion (71) is provided with a third accommodating hole (73), and a second clamping ring protrudes around the edge of the third accommodating hole (73), and the connecting aluminum sheet (32) is seated in the first annular groove (52).

5. The secondary lithium battery top cover capable of reducing welding power according to claim 2, characterized in that: The first groove (21) is in a major arc shape, and its opening is located on a side away from the center of the annular bracket (2).

6. The secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: It also includes a sealing ring (4). The positive pole (3) and the negative pole (9) are both sleeved with the sealing ring (4), and the side of the sealing ring close to the aluminum sheet (5) is in close contact with the first annular groove (52).

7. The secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: An explosion-proof hole is formed on the plain aluminum sheet (5), an explosion-proof valve (12) is installed in the explosion-proof hole, and an explosion-proof valve protective film (13) is connected to the top of the explosion-proof valve (12).

8. The secondary lithium battery top cover capable of reducing welding power according to claim 4, characterized in that: It also includes an aluminum nail, the second connecting portion (72) is provided with a recess (75) for accommodating the aluminum nail, the bare aluminum sheet (5) is provided with a first aluminum nail hole (55), the lower plastic (6) is provided with a second aluminum nail hole (64), and the aluminum nail is threadedly connected to the first aluminum nail hole (55) and the second aluminum nail hole (64).

9. The secondary lithium battery top cover capable of reducing welding power according to claim 1, characterized in that: The positive electrode pole (3) is connected to the positive electrode upper plastic (1) around its side, and the negative electrode pole (9) is connected to the negative electrode upper plastic (8) around its side.

10. The secondary lithium battery top cover capable of reducing welding power according to claim 8, characterized in that: A sealing aluminum sheet (11) is connected between the aluminum nail and the second aluminum nail hole (64).

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