Lithium battery with aluminum shell

Abstract

The utility model belongs to the field of lithium batteries, and particularly provides a lithium battery with an aluminum shell, which comprises a sealing nail body, the edge of the bottom face of the sealing nail body extends downwards in the height direction to form an abutting part. The abutting part extends out of the lower portion of the sealing nail body and abuts against the limiting step of the injection opening of the aluminum shell lithium battery, after the sealing nail is welded, the width of a molten pool is larger than the thickness of the side wall of a boss of the sealing nail, it is guaranteed that the side wall of the sealing nail and the side wall of the limiting step of a cover plate are completely fused, and therefore cracks at the bottom of the welding molten pool are completely eradicated.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of lithium battery, concretely relates to an aluminum shell lithium battery. BACKGROUND

[0002] The metal shell lithium battery generally has the following procedures: pole piece manufacturing, winding, shell assembling, baking, liquid injection, formation, sealing nail welding and testing. The sealing nail welding is a key procedure of the metal shell lithium battery, and the final sealing of the battery cell is completed by the sealing nail welding. The reliability of the welding directly affects the performance and safety of the product.

[0003] A sealing nail and cover plate cooperation mode is provided in the related art, which mainly sets a protrusion at the welding position to reduce the risk of weld cracking. This mode has certain improvement effect in engineering, but cannot completely eliminate the risk of cracking. The cracks caused by the stress of the molten pool generated by laser welding are a common problem. The generation of cracks reduces the actual effective depth of the welding pool, and in severe cases, through cracks occur, which will directly lead to sealing failure at the welding position and affect the performance and safety of the product.

[0004] How to avoid cracks in the molten pool after sealing nail welding is an urgent problem to be solved at present. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a sealing nail and an aluminum shell lithium battery.

[0006] In order to solve the above technical problems, the utility model provides a sealing nail, which comprises:

[0007] A sealing nail body;

[0008] The edge of the bottom surface of the sealing nail body extends downward along the height direction to form a resisting portion.

[0009] Further, the resisting portion is annular.

[0010] Further, the cross section of the resisting portion is rectangular.

[0011] Further, the cross section of the resisting portion is triangular.

[0012] Further, the height of the resisting portion is between 0.3-0.8mm.

[0013] Further, the sealing nail body is cylindrical or prismatic.

[0014] The utility model further provides an aluminum shell lithium battery, which comprises a battery body, a cover plate and the sealing nail as described above.

[0015] The cover plate is fixedly arranged on the battery body.

[0016] The cover plate is provided with a liquid injection port;

[0017] The liquid injection port extends upwardly to a limiting step;

[0018] The side wall of the sealing nail is attached to the side wall of the limiting step;

[0019] The sealing nail is welded on the limiting step and is adapted to seal the liquid injection port.

[0020] Further, the width of the molten pool formed after the sealing nail is welded to the cover plate is greater than the width of the widest part of the abutting portion;

[0021] The height of the molten pool formed after the sealing nail is welded to the cover plate is greater than the height of the sealing nail.

[0022] Further, the material of the sealing nail body is the same as that of the cover plate.

[0023] Further, the top surface of the sealing nail body is flush with the top surface of the limiting step.

[0024] The utility model discloses a sealing nail and aluminum shell lithium cell, wherein, the sealing nail includes: sealing nail body, the edge of the bottom surface of sealing nail body extends the abutting portion downwards along the height direction. BRIEF DESCRIPTION OF DRAWINGS

[0025] The utility model will be further explained in connection with the drawings and examples.

[0026] Figure 1 It is the sectional view of the sealing nail provided by the utility model embodiment.

[0027] Figure 2 It is the sectional view of another sealing nail provided by the utility model embodiment.

[0028] Figure 3 It is the plan view of the cover plate and sealing nail provided by the utility model embodiment.

[0029] Figure 4 It is the sectional view of the cover plate and sealing nail provided by the utility model embodiment.

[0030] Figure 5 It is Figure 4 The enlarged view of A in Fig.

[0031] Figure 6 is a sectional view of a part structure after the sealing nail and the cover plate are welded, provided by an embodiment of the present utility model.

[0032] In the drawing: 100, sealing nail body; 110, abutting part; 200, cover plate; 210, liquid injection port; 220, limiting step; 300, molten pool. DETAILED DESCRIPTION

[0033] The present utility model will be further described in detail in combination with the drawings. These drawings are all simplified schematic diagrams, and only schematically show the basic structure of the present utility model, so they only show the structure related to the present utility model.

[0034] EMBODIMENT

[0035] Please refer to Figures 1-5 At least one embodiment provides a sealing nail, comprising: a sealing nail body 100; the edge of the bottom surface of the sealing nail body 100 extends downward in the height direction to form an abutting part 110. By extending the abutting part 110 below the sealing nail body 100 and abutting with the limiting step 220 of the injection port of the aluminum shell lithium battery, after the sealing nail is welded, the width of the molten pool 300 is greater than the thickness of the sealing nail boss side wall, which ensures that the sealing nail side wall and the side wall of the limiting step 220 of the cover plate 200 are completely fused, thereby eliminating the generation of cracks at the bottom of the welding molten pool 300.

[0036] In order to ensure that the sealing nail and the limiting step 220 of the cover plate 200 are completely attached, in at least one embodiment, the abutting part 110 is annular. The abutting part 110 is a closed annular structure, thereby ensuring the stability of the connection between the sealing nail and the cover plate 200.

[0037] In some embodiments, the cross section of the abutting part 110 is rectangular (as shown in Figure 1 ) or triangular (as shown in Figure 2 ). It should be noted that no matter what the cross-sectional shape of the abutting part 110 is, the abutting part 110 needs to be completely attached with the side wall of the limiting step 220 of the cover plate 200.

[0038] In some embodiments, the height of the abutting part 110 is between 0.3-0.8mm. It should be noted that the height from the top surface of the sealing nail body 100 to the bottom surface of the abutting part 110 is adapted to the height of the limiting step 220 of the cover plate 200, that is, the top surface of the sealing nail needs to be flush with the top surface of the limiting step 220.

[0039] In some embodiments, the sealing nail body 100 is cylindrical or prismatic.

[0040] Please refer to Figures 3-6At least one embodiment further provides an aluminum shell lithium battery, comprising a battery body (not shown in the figure), a cover plate 200 and a sealing nail as described above; the cover plate 200 is fixedly arranged on the battery body; the cover plate 200 is provided with a liquid injection port 210; the liquid injection port 210 extends upwardly to a limiting step 220; the side wall of the sealing nail is attached to the side wall of the limiting step 220; the sealing nail is welded on the limiting step 220 and is adapted to block the liquid injection port 210. By extending the abutting part 110 below the sealing nail body 100 and abutting against the limiting step 220 of the injection port of the aluminum shell lithium battery, after the sealing nail is welded, the width of the molten pool 300 is greater than the thickness of the side wall of the sealing nail boss, so that the side wall of the sealing nail is completely fused with the side wall of the limiting step 220 of the cover plate 200, thereby preventing the generation of cracks at the bottom of the welding molten pool 300.

[0041] As shown in Figure 6 At least one embodiment, the width of the molten pool 300 formed after the sealing nail and the cover plate 200 are welded is greater than the width of the widest part of the abutting part 110; the height of the molten pool 300 formed after the sealing nail and the cover plate 200 are welded is greater than the height of the sealing nail.

[0042] It should be noted that, in order to ensure that the sealing nail body 100 and the cover plate 200 are completely fused, in at least one embodiment, the material of the sealing nail body 100 is the same as that of the cover plate 200.

[0043] In some embodiments, the top surface of the sealing nail body 100 is flush with the top surface of the limiting step 220.

[0044] In summary, the utility model provides a sealing nail and an aluminum shell lithium battery, wherein the sealing nail comprises: a sealing nail body 100; the edge of the bottom surface of the sealing nail body 100 extends downwardly along the height direction to form an abutting part 110. By extending the abutting part 110 below the sealing nail body 100 and abutting against the limiting step 220 of the injection port of the aluminum shell lithium battery, after the sealing nail is welded, the width of the molten pool 300 is greater than the thickness of the side wall of the sealing nail boss, so that the side wall of the sealing nail is completely fused with the side wall of the limiting step 220 of the cover plate 200, thereby preventing the generation of cracks at the bottom of the welding molten pool 300.

[0045] Each device (components without specific structure) selected in the application is a general standard component or a component known to those skilled in the art, and its structure and principle can be known by technical personnel through a technical manual or through a conventional experimental method. Moreover, the software programs involved in the application are prior art, and the application does not involve any improvement on the software programs.

[0046] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In the description of the present application, it should be pointed out that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0048] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit.

[0049] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical concept of the present application. The technical scope of the present application is not limited to the contents in the specification, and must be determined according to the scope of the claims.

Claims

1. An aluminum cased lithium battery characterized by, The battery body, the cover plate and the sealing nail are included; The sealing nail includes: The sealing nail body; The edge of the bottom surface of the sealing nail body extends downward in the height direction to form a resisting portion; The cover plate is fixedly arranged on the battery body; The cover plate is provided with a liquid injection opening; The liquid injection opening extends upward to form a limiting step; The side wall of the sealing nail is matched with the side wall of the limiting step; The sealing nail is welded on the limiting step and is adapted to seal the liquid injection opening; The width of the molten pool formed after the sealing nail and the cover plate are welded is greater than the width of the widest part of the resisting portion; The height of the molten pool formed after the sealing nail and the cover plate are welded is greater than the height of the sealing nail.

2. The aluminum shell lithium battery of claim 1, wherein: The material of the sealing nail body is the same as that of the cover plate.

3. The aluminum shell lithium battery of claim 1, wherein: The height of the top surface of the sealing nail body is flush with the top surface of the limiting step.

4. The aluminum shell lithium battery of claim 1, wherein: The resisting portion is annular.

5. The aluminum shell lithium battery of claim 4, wherein: The cross section of the resisting portion is rectangular.

6. The aluminum shell lithium battery of claim 4, wherein: The cross section of the resisting portion is triangular.

7. The aluminum shell lithium battery of claim 1, wherein: The height of the resisting portion is between 0.3-0.8mm.

8. The aluminum shell lithium battery of claim 1, wherein: The sealing nail body is cylindrical or prismatic.

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