Lithium ion battery sealing structure

Abstract

The utility model belongs to the technical field of lithium batteries, and particularly relates to a lithium ion battery sealing structure. The lithium ion battery sealing structure provided by the utility model comprises a battery cover plate and a sealing nail, a liquid injection hole is arranged above the battery cover plate, the sealing nail is matched with the liquid injection hole for use, the liquid injection hole is a stepped hole of which the diameter is sequentially reduced from top to bottom, and the liquid injection hole is sequentially composed of a counterbore, a sealing hole and a connecting hole from top to bottom. The sealing nail is composed of a nail head and a nail column, a limiting table is arranged at the bottom of the nail column, a sealing ring is arranged at the position, located at the sealing hole, of the nail column from bottom to top, sealing washers are arranged at the bottom of the nail head and the counterbore, the shape of the nail head is matched with the shape of the counterbore, and the nail head is fixed to the edge of the counterbore through welding.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium batteries, and in particular relates to a lithium ion battery sealing structure. Background Art

[0002] Sealing pin welding is an important process to ensure the sealing of lithium-ion batteries. The leakage caused by the failure of the battery sealing pins is mainly caused by defects such as explosion points, welding pits, holes, broken welds, and pin lift. At present, the sealing pins of square aluminum shell batteries in the industry are generally aluminum stamping structure discs.

[0003] At present, the disc-type sealing pin only plays the role of a single-layer seal. When the rubber pin seal of the liquid filling port fails and there are defects in the sealing pin welding, if it is not detected at the battery cell manufacturing end, it will inevitably cause abnormal leakage when it flows to the customer end, resulting in problems in the use of the battery cell. Therefore, a lithium-ion battery sealing structure is proposed. Utility Model Content

[0004] The technical problem to be solved by the utility model is that the sealing nail only plays the role of a single-layer seal. When the sealing of the rubber nail of the liquid filling port fails and is not detected, it will inevitably cause abnormal leakage, resulting in problems in the use of the battery cell.

[0005] In order to solve the above technical problems, the technical solution provided by the utility model is: a lithium-ion battery sealing structure, including a battery cover and a sealing nail, a liquid injection hole is arranged on the top of the battery cover, and the sealing nail is used in conjunction with the liquid injection hole, the liquid injection hole is a stepped hole whose diameter decreases from top to bottom, and the liquid injection hole is composed of a countersunk hole, a sealing hole and a connecting hole from top to bottom, the sealing nail is composed of a nail head and a nail column, a limiting platform is arranged at the bottom of the nail column, and a sealing ring is arranged from bottom to top at the nail column located at the sealing hole, a sealing gasket is arranged at the bottom of the nail head and the countersunk hole, and the shape of the nail head matches that of the countersunk hole, and the nail head is fixed to the edge of the countersunk hole by welding.

[0006] Preferably, the countersunk hole protrudes from the upper end surface of the battery cover plate, and the height of the countersunk hole is greater than the thickness of the nail head and the sealing gasket.

[0007] Through the above technical solution, there is a space for filling the UV adhesive layer between the nail head and the countersunk hole after welding.

[0008] Preferably, the countersunk hole and the nail head are located at the welding position to form a welding ring, and a UV adhesive layer is filled between the top of the welding ring and the countersunk hole.

[0009] Through the above technical solution, the effects of fixing and further sealing can be achieved through welding and UV adhesive layer.

[0010] Preferably, the diameter of the sealing hole is larger than the diameter of the nail column and the limiting platform.

[0011] The above technical solution makes it easy for the nail column and the limit platform to pass through the sealing hole, and a sealing ring with a larger diameter can be placed for extrusion sealing.

[0012] Preferably, the connection hole matches the diameter of the nail column, and the connection hole has the same height as the sealing hole.

[0013] Through the above technical solution, the gap between the connection hole and the nail column is reduced when the nail column passes through the connection hole, and at the same time, the depth and size of the connection hole and the sealing hole can be conveniently determined by the same height.

[0014] Preferably, the length of the nail column is the same as the height of the sealing hole, the connecting hole and the sealing gasket added together, the limiting platform is located at the bottom of the nail column, and the length of the limiting platform is independent of the nail column.

[0015] Through the above technical solution, it is convenient to determine the required length of the nail column, and fix it through the limit platform and the bottom of the connecting hole.

[0016] Preferably, the limiting platform is an inverted frustum structure that gradually increases from the bottom to the top, and the maximum diameter of the limiting platform is 0.5 mm greater than the diameter of the connecting hole.

[0017] Through the above technical solution, it is convenient for the limit platform to enter the interior of the injection hole from above, and to be fixed and sealed with the bottom of the connecting hole by means of interference fit.

[0018] Preferably, the sealing ring is an annular cylindrical structure made of rubber material, and the outer diameter of the sealing ring is the same as the diameter of the sealing hole, the inner diameter of the sealing ring is the same as the diameter of the nail column, and the height of the sealing ring is greater than the height at the sealing hole.

[0019] Through the above technical solution, the sealing ring can be squeezed so that the sealing ring fills the gap at the sealing hole, thereby increasing the sealing effect.

[0020] Preferably, the sealing gasket is made of metal, and the diameter of the sealing gasket is the same as that of the countersunk hole.

[0021] Through the above technical solution, it is convenient to weld and fix the sealing gasket and the nail head, and at the same time the hardness of the sealing gasket is increased, which makes it easier to squeeze the sealing gasket.

[0022] The advantages of the utility model compared with the prior art are:

[0023] The sealing structure uses a stepped injection hole, and a sealing nail is set to be plugged and sealed with the injection hole by means of a sealing ring and a sealing gasket, and an interference fit is formed with the lower end of the injection hole through a limit table to achieve a secondary sealing effect. The entire process only requires the sealing nail to be driven into the injection hole to seal, and a complete sealing effect is achieved through subsequent welding and filling with UV glue. The structure is simple, the installation is convenient, no leakage will occur, and the battery core can be effectively prevented from abnormalities. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural diagram of a lithium-ion battery sealing structure of the utility model;

[0025] Figure 2 This is a structural diagram of a liquid injection hole of a lithium-ion battery sealing structure of the utility model;

[0026] Figure 3 This is a sealing nail structure diagram of a lithium-ion battery sealing structure of the utility model;

[0027] Figure 4 This is an exploded view of a sealing nail connection structure of a lithium-ion battery sealing structure of the utility model.

[0028] As shown in the figure: 1. Battery cover; 2. Sealing nail; 3. Injection hole; 4. Countersunk hole; 5. Sealing hole; 6. Connection hole; 7. Nail head; 8. Nail column; 9. Limiting platform; 10. Sealing ring; 11. Sealing gasket; 12. Welding ring; 13. UV adhesive layer. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] In the description of the utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0031] Embodiment 1:

[0032] As shown in Attachments 1-4 of the specification, a lithium-ion battery sealing structure includes a battery cover 1 and a sealing nail 2. A liquid injection hole 3 is provided above the battery cover 1, and the sealing nail 2 is used in conjunction with the liquid injection hole 3. The liquid injection hole 3 is a stepped hole whose diameter decreases from top to bottom, and the liquid injection hole 3 is composed of a countersunk hole 4, a sealing hole 5 and a connecting hole 6 from top to bottom. The countersunk hole 4 protrudes from the upper end surface of the battery cover 1, and the height of the countersunk hole 4 is greater than the thickness of the nail head 7 and the sealing gasket 11.

[0033] In the present invention, the sealing nail 2 is composed of a nail head 7 and a nail column 8. A limiting platform 9 is arranged at the bottom of the nail column 8. The diameter of the sealing hole 5 is larger than the diameter of the nail column 8 and the limiting platform 9. The nail column 8 is located at the sealing hole 5 and a sealing ring 10 is arranged from bottom to top. The sealing ring 10 is an annular column structure made of rubber material, and the outer diameter of the sealing ring 10 is the same as the diameter of the sealing hole 5, the inner diameter of the sealing ring 10 is the same as the diameter of the nail column 8, the height of the sealing ring 10 is greater than the height at the sealing hole 5, the connecting hole 6 matches the diameter of the nail column 8, and the connecting hole 6 and the sealing hole 5, the length of the nail column 8 is the same as the height of the sealing hole 5, the connecting hole 6 and the sealing gasket 11 added together, the limit platform 9 is located at the bottom of the nail column 8, and the length of the limit platform 9 is independent of the nail column 8, the limit platform 9 is an inverted frustum structure that gradually increases from the bottom to the top, and the maximum diameter of the limit platform 9 is 0.5mm larger than the diameter of the connecting hole 6, a sealing gasket 11 is provided at the bottom of the nail head 7 and the countersunk hole 4, the sealing gasket 11 is made of metal, and the diameter of the sealing gasket 11 is the same as that of the countersunk hole 4, and the shape of the nail head 7 matches that of the countersunk hole 4.

[0034] In the present invention, the nail head 7 and the edge of the countersunk hole 4 are fixed by welding, the countersunk hole 4 and the nail head 7 are located at the welding position to form a welding circle 12, and a UV adhesive layer 13 is filled between the upper part of the welding circle 12 and the countersunk hole 4.

[0035] In the specific implementation of the utility model, the sealing gasket 11 and the sealing ring 10 are sleeved on the sealing nail 2. After the injection is completed, the sealing nail 2 is directly driven into the injection hole 3, so that the limiting platform 9 at the bottom of the sealing nail 2 forms an interference fit with the bottom of the connecting hole 6 to perform sealing and limiting. At the same time, the nail head 7 squeezes the sealing ring 10 to increase the sealing effect, and the sealing gasket 11 fills the gap between the countersunk hole 4 and the sealing hole 5 while assisting in squeezing the sealing ring 10; then, the upper part of the nail head 7 is welded to the countersunk hole 4, and the UV glue layer 13 is filled between the countersunk hole 4 and the welding ring 12 formed by welding, so as to achieve a thorough fixed sealing effect, and the whole presents a three-layer seal.

[0036] The above describes the utility model and its implementation methods, which are not restrictive. The specific implementation method is only one of the implementation methods of the utility model, and the actual structure is not limited thereto. In short, if ordinary technicians in this field are inspired by it, without departing from the purpose of the invention of the utility model, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the utility model.

Claims

1. A lithium-ion battery sealing structure, comprising a battery cover and a sealing nail, wherein a liquid injection hole is provided above the battery cover, and the sealing nail is used in conjunction with the liquid injection hole, characterized in that: The injection hole is a stepped hole whose diameter decreases from top to bottom, and the injection hole is composed of a countersunk hole, a sealing hole and a connecting hole from top to bottom. The sealing nail is composed of a nail head and a nail column. A limiting platform is provided at the bottom of the nail column, and a sealing ring is provided from bottom to top at the nail column located at the sealing hole. A sealing gasket is provided at the bottom of the nail head and the countersunk hole, and the shape of the nail head matches that of the countersunk hole. The nail head and the edge of the countersunk hole are fixed by welding.

2. A lithium-ion battery sealing structure according to claim 1, characterized in that: The countersunk hole protrudes from the upper end surface of the battery cover plate, and the height of the countersunk hole is greater than the thickness of the nail head and the sealing gasket.

3. A lithium-ion battery sealing structure according to claim 1, characterized in that: The countersunk hole and the nail head are located at the welding position to form a welding circle, and a UV glue layer is filled between the top of the welding circle and the countersunk hole.

4. A lithium-ion battery sealing structure according to claim 1, characterized in that: The diameter of the sealing hole is larger than the diameter of the nail column and the limiting platform.

5. A lithium-ion battery sealing structure according to claim 1, characterized in that: The connection hole matches the diameter of the nail column, and the connection hole has the same height as the sealing hole.

6. A lithium-ion battery sealing structure according to claim 1, characterized in that: The length of the nail column is the same as the height of the sealing hole, the connecting hole and the sealing gasket added together. The limiting platform is located at the bottom of the nail column, and the length of the limiting platform is independent of the nail column.

7. A lithium-ion battery sealing structure according to claim 1, characterized in that: The limiting platform is an inverted frustum structure that gradually increases from the bottom to the top, and the maximum diameter of the limiting platform is 0.5 mm greater than the diameter of the connecting hole.

8. A lithium-ion battery sealing structure according to claim 1, characterized in that: The sealing ring is an annular column structure made of rubber material, and the outer diameter of the sealing ring is the same as the diameter of the sealing hole, the inner diameter of the sealing ring is the same as the diameter of the nail column, and the height of the sealing ring is greater than the height at the sealing hole.

9. A lithium-ion battery sealing structure according to claim 1, characterized in that: The sealing gasket is made of metal, and the diameter of the sealing gasket is the same as that of the countersunk hole.

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