A top cover protection film and a battery

Abstract

The utility model relates to lithium battery technical field especially relates to a top cover protection film, including the membrane body, wherein, the membrane body is used for sticking in the top surface of battery top cover, be equipped with the first protection department of groove on the membrane body, the first protection department is used for sticking and embedding in the slot -shaped liquid injection mouth of battery top cover, carries out full coverage to the bottom surface and lateral wall of slot -shaped liquid injection mouth, the bottom of first protection department is equipped with through -hole, the through -hole is used for with the liquid injection hole in the slot -shaped liquid injection mouth opposite arrangement, to make the liquid injection hole and outside intercommunication, the utility model proposes a kind of top cover protection film and battery, the protection film covers slot -shaped liquid injection mouth on battery top cover by its first protection department, realizes the effective isolation of liquid injection mouth and electrolyte, avoids electrolyte residue, crystallization and corrosion problem to appear, improves the yield and security of subsequent sealing nail welding.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a top cover protective film and a battery. Background Technology

[0002] With the widespread application of lithium batteries in the new energy field, square aluminum-cased lithium batteries have become the mainstream product due to their stable structure and high assembly efficiency. In the manufacturing process of square aluminum-cased batteries, electrolyte injection is one of the key processes, which usually requires two injections through the injection port on the top cover to ensure that the electrolyte fully wets the electrode materials.

[0003] In actual production, electrolyte overflow often occurs because the injection speed is inconsistent with the filling speed inside the cell. Therefore, injection equipment is usually equipped with a wiping mechanism to remove residual liquid, such as the device for removing electrolyte from the injection port of lithium battery disclosed in the invention with authorization announcement number CN113851797B.

[0004] Since the top cover injection port is generally a groove structure, the wiping mechanism has difficulty in completely removing the residual electrolyte in the tank. The crystallization of the residual electrolyte will affect the subsequent welding quality of the sealing nails, and may even cause defects such as weld explosion. Utility Model Content

[0005] In view of this, the present invention proposes a top cover protective film and a battery. The protective film covers the groove-shaped liquid injection port on the top cover of the battery through its first protective part, thereby effectively isolating the liquid injection port and the electrolyte, avoiding problems such as electrolyte residue, crystallization and corrosion, and improving the yield and safety of subsequent sealing nail welding.

[0006] The technical solution of this utility model is implemented as follows:

[0007] On the one hand, the present invention provides a top cover protective film, including a film body, wherein the film body is used to adhere to the top surface of the battery top cover;

[0008] The membrane is provided with a grooved first protective part;

[0009] The first protective part is used to adhere to and be embedded in the groove-shaped liquid injection port of the battery top cover to fully cover the bottom surface and side wall of the groove-shaped liquid injection port;

[0010] The bottom of the first protective part is provided with a through hole, which is used to be arranged opposite to the injection hole in the groove-shaped injection port so that the injection hole can communicate with the outside.

[0011] Based on the above technical solutions, preferably, the through hole and the injection hole are concentrically arranged, and the inner diameter of the through hole is less than or equal to the inner diameter of the injection hole.

[0012] Based on the above technical solutions, preferably, the outer surface of the first protective part and the bottom surface of the membrane are both provided with an adhesive coating.

[0013] Based on the above technical solutions, preferably, the edge region along the length of the membrane has a glue-free area reserved.

[0014] Based on the above technical solution, preferably, the membrane body is provided with two electrode mating holes, wherein,

[0015] The upper edge of the pole fitting hole extends upward to form a cylindrical second protective part;

[0016] The second protective part is used to cover the outside of the terminal post of the battery top cover.

[0017] Based on the above technical solutions, preferably, the inner side of the second protective part is in close contact with the outer side of the pole post.

[0018] Based on the above technical solutions, preferably, the membrane body is provided with an explosion-proof valve mating hole, wherein,

[0019] The upper edge of the explosion-proof valve mating hole extends upward to form a cylindrical third protective part;

[0020] The third protective part is used to cover the outside of the explosion-proof valve on the top cover of the battery.

[0021] Based on the above technical solutions, preferably, the vertical height of the third protective part is equal to that of the second protective part.

[0022] Based on the above technical solutions, preferably, the membrane body, the first protective part, the second protective part, and the third protective part are integrally formed.

[0023] On the other hand, this utility model also provides a battery, including the aforementioned top cover protective film and battery top cover, and also including a battery cell body, wherein,

[0024] The battery top cover is fixed to the top of the battery cell body;

[0025] The top of the battery cover is peelably provided with the cover protective film.

[0026] The top cover protective film and battery of this utility model have the following advantages over the prior art:

[0027] (1) By attaching a membrane structure with a first protective part to the top cover of the battery, and embedding the first protective part into the injection port and fully covering its bottom and side walls, the electrolyte that may overflow during the injection process is effectively isolated, preventing electrolyte residue and crystallization at the injection port, which could lead to poor welding of the sealing nail. At the same time, a through hole is opened at the bottom of the first protective part, which is set opposite to the injection hole to ensure that the injection process proceeds normally and improves the production yield and safety of the battery cell.

[0028] (2) By reserving a glue-free area in the edge region along the length of the membrane, the protective film on the top cover can be easily removed after the liquid injection is completed, thus improving the efficiency of operation.

[0029] (3) By setting a second protective part on the outside of the electrode post, the electrode post and its root sealing structure are effectively protected. At the same time, by setting a third protective part on the explosion-proof valve, the electrolyte is prevented from flowing into the explosion-proof valve or seeping in along the gap at the root of the electrode post during the liquid injection process. This effectively avoids the electrolyte from corroding the explosion-proof valve and the gasket inside the electrode post, and improves the safety and long-term reliability of the battery.

[0030] (4) A protective film can be peeled off on the top of the battery cover. This not only effectively prevents scratches, dirt and other appearance defects from appearing on the surface of the cover during the manufacturing process, but also reduces the reliance on the electrolyte wiping mechanism in practical applications. It can even eliminate the wiping mechanism, simplify the process, reduce equipment costs and energy consumption, and has good industrialization promotion value. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a perspective view of a top cover protective film according to the present invention;

[0033] Figure 2 This is a schematic diagram of the structure after the top cover has been coated with film;

[0034] Figure 3 An exploded view of the protective film on the top cover and the top cover itself;

[0035] Figure 4 This is a perspective view of a battery according to the present invention;

[0036] In the diagram: 1. Membrane; 2. Battery top cover; 3. Cell body; 11. First protective section; 21. Groove-shaped liquid injection port; 22. Terminal post; 23. Explosion-proof valve; 101. Glue-free area; 102. Terminal post mating hole; 103. Explosion-proof valve mating hole; 1021. Second protective section; 1031. Third protective section; 1101. Through hole; 2101. Liquid injection hole. Detailed Implementation

[0037] The technical solutions of this utility model will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0038] like Figure 4 As shown, the battery provided by this utility model includes a cell body 3 and a battery top cover 2 fixedly disposed on the top of the cell body 3. The battery top cover 2 is provided with a groove-shaped liquid injection port 21, a terminal post 22, and an explosion-proof valve 23, wherein a liquid injection hole 2101 is formed in the groove-shaped liquid injection port 21. A top cover protective film is peelably disposed on the top of the battery top cover 2 for effectively protecting the top surface of the battery top cover 2 and its associated structures.

[0039] Specifically, the top cover protective film ensures the cleanliness of the inside of the groove-shaped injection port 21, avoiding crystallization problems caused by electrolyte residue, thereby improving the yield of subsequent sealing nail welding. At the same time, the top cover protective film also prevents electrolyte from flowing into the explosion-proof valve 23 or seeping in along the gap at the root of the terminal post 22 during the injection process, thus effectively preventing electrolyte from corroding the explosion-proof valve 23 assembly and the gasket inside the terminal post 22, significantly improving the battery's safety performance and long-term reliability.

[0040] Furthermore, the application of the top cover protective film can effectively prevent scratches, dirt, and other appearance defects from occurring on the battery top cover 2 during manufacturing, handling, and assembly. Simultaneously, it can reduce reliance on existing electrolyte wiping mechanisms in practical applications, and may even eliminate these mechanisms altogether, simplifying the process flow, reducing equipment costs and energy consumption, and possessing significant industrialization potential. Because the top cover protective film has a peelable structure, it can be removed as needed without affecting subsequent battery processing and packaging operations, making it convenient and highly adaptable.

[0041] like Figure 1-4As shown, the aforementioned top cover protective film includes a film body 1, which is used to adhere to the top surface of the battery top cover 2 to cover at least a portion of the top surface. A groove-shaped first protective portion 11 is provided on the film body 1. The first protective portion 11 is used to adhere to and be embedded in the groove-shaped liquid injection port 21 of the battery top cover 2 to fully cover the bottom surface and sidewalls of the groove-shaped liquid injection port 21. A through hole 1101 is provided at the bottom of the first protective portion 11, which is arranged opposite to the liquid injection hole 2101 in the groove-shaped liquid injection port 21 to allow the liquid injection hole 2101 to communicate with the outside.

[0042] In practical applications, the first protective part 11 is embedded in the groove-shaped injection port 21 and bonded and fixed. The membrane 1 is pasted on the top surface of the battery top cover 2. After bonding, the first protective part 11 and the membrane 1 provide joint protection, effectively isolating electrolyte that may overflow during the injection process and preventing electrolyte residue and crystallization at the injection port, which could lead to poor welding of the sealing nail. Since the through hole 1101 and the injection hole 2101 are arranged opposite to each other, the injection end of the electrolyte injection device can pass through the through hole 1101 to reach the injection hole 2101, ensuring that the injection process proceeds normally.

[0043] Furthermore, the through hole 1101 and the injection hole 2101 are concentrically arranged, ensuring axial consistency of the injection path and improving injection efficiency. Simultaneously, the inner diameter of the through hole 1101 is less than or equal to the inner diameter of the injection hole 2101, effectively preventing electrolyte leakage from the gap, enhancing sealing, and ensuring the safety and stability of the injection process.

[0044] In addition, to improve the adhesion stability of the protective film on the top cover, both the outer surface of the first protective part 11 and the bottom surface of the film body 1 are provided with a self-adhesive coating. The self-adhesive coating has good adhesion and is easy to remove after liquid injection, leaving no adhesive residue on the surface of the top cover, thus avoiding subsequent processing problems caused by residual adhesive.

[0045] Furthermore, a non-adhesive area 101 is reserved on the edge of the membrane 1 along its length, which facilitates the removal of the membrane 1 by using the edge of the membrane 1 in the non-adhesive area 101. This reduces the difficulty of peeling, improves the efficiency of operation, and is beneficial for the automation of the production line.

[0046] like Figure 1-4 As shown, the membrane 1 is further provided with two terminal fitting holes 102, and the upper edge of each terminal fitting hole 102 extends upward to form a cylindrical second protective part 1021. The second protective part 1021 is used to fit over the outside of the terminal 22 of the battery top cover 2, and provides effective isolation and protection for the terminal 22 and its root sealing structure, preventing electrolyte from seeping in along the gap at the root of the terminal 22, corroding the gasket or affecting the airtightness.

[0047] Furthermore, the inner surface of the second protective part 1021 is tightly fitted to the outer surface of the pole post 22, which enhances the sealing performance between the second protective part 1021 and the pole post 22 and further improves the protective effect.

[0048] In addition, the membrane body 1 is provided with an explosion-proof valve mating hole 103, the upper edge of which extends upward to form a cylindrical third protective part 1031. The third protective part 1031 is used to fit over the outside of the explosion-proof valve 23 of the battery top cover 2 to prevent electrolyte from flowing into the interior of the explosion-proof valve 23 during the liquid injection process, and to avoid corrosion of the explosion-proof valve 23 due to electrolyte accumulation, which would affect its sensitivity.

[0049] Furthermore, the third protective part 1031 and the second protective part 1021 have the same vertical height, ensuring that the overall structure of the membrane 1 is flat, which facilitates the bonding and peeling operations.

[0050] The membrane 1, together with the first protective part 11, the second protective part 1021 and the third protective part 1031, is an integrally molded structure. It is made of PET, PP or other plastic polymer materials and has good flexibility, corrosion resistance and processing performance, which can meet the needs of industrial mass production.

[0051] In practical application, the aforementioned top cover protective film involves embedding the first protective part 11 into the grooved liquid injection port 21 on the battery top cover 2 and then bonding and fixing it in place. Next, the film body 1 is attached to the top surface of the battery top cover 2, ensuring that the film body 1 covers at least a portion of the surface of the battery top cover 2. During this process, the second protective part 1021 should be accurately fitted onto the outside of the corresponding terminal 22, and the third protective part 1031 should be fitted onto the periphery of the explosion-proof valve 23. In this way, the top cover protective film can effectively isolate electrolyte that may overflow during the liquid injection process, preventing it from remaining or crystallizing at the injection port, and preventing electrolyte from entering the explosion-proof valve 23 or seeping in along the gap at the root of the terminal 22, thereby improving battery safety and long-term reliability.

[0052] When it is necessary to remove the protective film on the top cover, the film 1 can be peeled off by using the edge of the film 1 in the adhesive-free area 101.

[0053] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A top cover protective film, comprising a film body (1), wherein, The membrane (1) is used to adhere to the top surface of the battery top cover (2); Its characteristic is that: the membrane (1) is provided with a groove-shaped first protective part (11); The first protective part (11) is used to adhere to and be embedded in the groove-shaped liquid injection port (21) of the battery top cover (2) to fully cover the bottom surface and side wall of the groove-shaped liquid injection port (21); The bottom of the first protective part (11) is provided with a through hole (1101), which is used to be arranged opposite to the injection hole (2101) in the groove-shaped injection port (21) so that the injection hole (2101) can communicate with the outside.

2. The protective film for a top cover as described in claim 1, characterized in that: The through hole (1101) and the injection hole (2101) are concentrically arranged, and the inner diameter of the through hole (1101) is less than or equal to the inner diameter of the injection hole (2101).

3. The protective film for a top cover as described in claim 1, characterized in that: The outer surface of the first protective part (11) and the bottom surface of the membrane (1) are both provided with an adhesive coating.

4. The protective film for a top cover as described in claim 1, characterized in that: The edge region along the length of the membrane (1) has a reserved adhesive-free area (101).

5. The protective film for a top cover as described in claim 1, characterized in that: The membrane (1) is provided with two pole fitting holes (102), wherein, The upper edge of the pole fitting hole (102) extends upward to form a cylindrical second protective part (1021). The second protective part (1021) is used to be fitted onto the outside of the terminal post (22) of the battery top cover (2).

6. The protective film for a top cover as described in claim 5, characterized in that: The inner side of the second protective part (1021) is in close contact with the outer side of the pole post (22).

7. A top cover protective film as described in claim 6, characterized in that: The membrane (1) is provided with an explosion-proof valve mating hole (103), wherein, The upper edge of the explosion-proof valve mating hole (103) extends upward to form a cylindrical third protective part (1031). The third protective part (1031) is used to be fitted onto the outside of the explosion-proof valve (23) of the battery top cover (2).

8. A top cover protective film as described in claim 7, characterized in that: The third protective part (1031) has the same vertical height as the second protective part (1021).

9. A top cover protective film as described in claim 8, characterized in that: The membrane (1) is integrally formed with the first protective part (11), the second protective part (1021) and the third protective part (1031).

10. A battery, characterized in that: Including the top cover protective film as described in any one of claims 1-9 and the battery top cover (2), it also includes the battery cell body (3), wherein, The battery top cover (2) is fixed to the top of the battery cell body (3); The top of the battery top cover (2) is peelably provided with the top cover protective film.

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