Lithium ion battery upper cover plate capable of secondary liquid injection

Abstract

The utility model discloses a lithium ion battery upper cover plate capable of secondary liquid injection, and belongs to the technical field of lithium battery upper covers. A detachable sealing mechanism is arranged in the liquid injection hole of the upper cover plate body and comprises a sealing nail and a sealing plug; the sealing nail comprises a nail rod and a nail head; the inner side wall of the upper groove of the liquid injection hole is provided with internal threads; a sealing plug is arranged in a lower hole of the liquid injection hole; the nail head is fixed to the upper end of the nail rod, the nail rod is inserted into the sealing plug in an interference mode, external threads are arranged on the side wall of the nail head, and the nail head is fixedly connected with the upper groove through screwing of the internal threads and the external threads. The battery electrolyte injection device is simple in structure and convenient to operate, the sealing plug is inserted into the electrolyte injection hole, then the sealing nail is inserted into the sealing plug, the electrolyte injection hole is sealed, multiple times of electrolyte injection of a battery is achieved, circumferential and axial friction resistance is provided for the sealing nail through the sealing plug, axial fixing of the sealing nail is achieved, and the sealing effect of the battery is improved. The sealing nail is prevented from loosening in a long-term use process, the reliability of threaded connection is ensured, and the service life of the battery is effectively prolonged.

Description

Technical Field

[0001] The utility model relates to an upper cover plate of a lithium-ion battery capable of secondary liquid injection, belonging to the technical field of upper covers of lithium batteries. Background Art

[0002] Most traditional lithium-ion batteries adopt a liquid electrolyte system, which requires injecting an appropriate amount of electrolyte into the battery during production to ensure the normal operation of the battery. To achieve the injection and sealing of the electrolyte, a liquid injection hole is specially designed on the upper cover plate of the lithium battery to accurately inject the electrolyte into the battery cell. After the injection, formation, and possible supplementary liquid operations of the electrolyte are completed, the liquid injection hole needs to be sealed to prevent electrolyte leakage and external impurity intrusion, thereby ensuring the safety and performance of the battery.

[0003] However, there are significant limitations in the sealing methods of liquid injection holes in the prior art. A common practice is to directly hammer a steel ball with a diameter slightly larger than the liquid injection hole into the hole for sealing, or to use a rubber nail and a sealing aluminum sheet for welding and plugging. Although these methods can effectively seal the liquid injection hole, they are all one-time and non-detachable permanent sealing methods. This means that once the battery is initially filled with liquid and sealed, it cannot be opened again for supplementary liquid or multiple liquid injection operations, greatly limiting the battery's reuse rate and service life.

[0004] To overcome the above deficiencies, the Chinese utility model patent with the patent publication number CN218632248U and the name "A Battery Cover Plate Capable of Recycling and Secondary Liquid Injection" seals the liquid injection hole by threadedly connecting a sealing screw and uses a sealing ring for sealing. Although this solution improves the sealing flexibility and maintainability to a certain extent, there is still a risk of loosening of the threaded connection during the long-term operation of the battery or under complex working conditions, which may lead to a decline or even failure of the sealing performance, thereby affecting the overall performance and safety of the battery.

[0005] Therefore, there is an urgent need for a more reliable, efficient, and easy-to-maintain solution for liquid injection hole sealing and secondary liquid injection. Summary of the Utility Model

[0006] To solve the problems in the background art, the utility model provides an upper cover plate of a lithium-ion battery capable of secondary liquid injection.

[0007] To achieve the above object, the present utility model adopts the following technical solutions: An upper cover plate of a lithium-ion battery capable of secondary liquid injection, comprising an upper cover plate body; the vertical cross-section of the liquid injection hole of the upper cover plate body is T-shaped, and a detachable sealing mechanism is provided in the liquid injection hole, and the sealing mechanism includes a sealing nail and a sealing plug; the sealing nail includes a nail rod and a nail head; the inner side wall of the upper groove of the liquid injection hole is provided with an internal thread; a sealing plug is provided in the lower hole of the liquid injection hole; the nail head is coaxially fixed at the upper end of the nail rod, the nail rod is press-fitted into the sealing plug, the side wall of the nail head is provided with an external thread, and the nail head is fixedly connected to the upper groove through the screwing connection of the internal thread and the external thread.

[0008] The sealing plug includes a sleeve and a limiting ring; the limiting ring is coaxially fixed at the upper end of the sleeve, the sleeve is arranged in the lower hole, the lower surface of the limiting ring is attached to the bottom surface of the upper groove, and the sleeve is press-fitted on the outside of the nail rod.

[0009] The lower end of the sleeve is a closed end.

[0010] The lower end of the outer wall of the sleeve is provided with an annular extension part, and when the sleeve is completely inserted into the lower hole, the annular extension part is closely attached to the lower surface of the upper cover plate body.

[0011] A chamfer is provided at the connection between the upper groove and the lower hole.

[0012] A cross-shaped opening is provided in the middle of the upper top surface of the nail head.

[0013] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0014] The structure of the present utility model is simple and the operation is convenient. Insert the sealing plug into the liquid injection hole and then insert the sealing nail into the sealing plug, which not only ensures the sealing of the liquid injection hole but also realizes multiple liquid injections for the battery. At the same time, the sealing plug provides circumferential and axial frictional resistance to the sealing nail, realizing the axial fixation of the sealing nail, preventing the sealing nail from loosening during long-term use, ensuring the reliability of the threaded connection, and effectively extending the service life of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic structural diagram of the present utility model;

[0016] Figure 2 is Figure 1 an enlarged view of part A of

[0017] Figure 3 is a schematic structural diagram of the sealing nail;

[0018] Figure 4 is a schematic diagram of the connection relationship between the sealing plug and the liquid injection hole;

[0019] Figure 5 is Figure 4Enlarged view of part B;

[0020] Figure 6 It is a schematic structural diagram after the sealing mechanism is installed on the upper cover body. Specific embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] A lithium-ion battery upper cover capable of secondary liquid injection includes an upper cover body 10. The vertical cross-section of the liquid injection hole 40 of the upper cover body 10 is T-shaped. A detachable sealing mechanism is provided in the liquid injection hole 40. The sealing mechanism includes a sealing nail 20 and a sealing plug 30. The sealing nail 20 includes a nail rod 21 and a nail head 22. An internal thread 43 is provided on the inner side wall of the upper groove 42 of the liquid injection hole 40. A sealing plug 30 is provided in the lower hole 41 of the liquid injection hole 40. The nail head 22 is coaxially and integrally formed and fixed at the upper end of the nail rod 21. The nail rod 21 is press-fitted into the sealing plug 30. An external thread 23 is provided on the side wall of the nail head 22. The nail head 22 and the upper groove 42 are fixedly connected by screwing the internal thread 43 and the external thread 23, so as to realize the sealing of the liquid injection hole 40 by the sealing nail 20.

[0023] The sealing plug 30 is made of rubber and includes a sleeve 31 and a limit ring 33. The limit ring 33 is coaxially and integrally formed and fixed at the upper end of the sleeve 31. The sleeve 31 is arranged in the lower hole 41. The lower surface of the limit ring 33 is attached to the bottom surface of the upper groove 42. The sleeve 31 is press-fitted and sleeved on the outside of the nail rod 21.

[0024] The sleeve 31 is placed in the lower hole 41 with a gap, and the nail rod 21 is press-fitted into the sleeve 31, that is: the outer diameter of the nail rod 21 is greater than the inner diameter of the sleeve 31, the outer diameter of the sleeve 31 is less than the inner diameter of the lower hole 41, and the difference between the outer diameter of the nail rod 21 and the inner diameter of the sleeve 31 is greater than the difference between the outer diameter of the sleeve 31 and the inner diameter of the lower hole 41. In this way, when the sleeve 31 is inserted into the lower hole 41 and then the nail rod 21 is inserted into the sleeve 31, the diameter of the sleeve 31 also becomes larger. At this time, the sleeve 31 is in an interference fit with both the nail rod 21 and the lower hole 41, so as to realize the sealing of the liquid injection hole 40.

[0025] The lower end of the sleeve 31 is a closed end to prevent the electrolyte from entering the gap between the nail rod 21 and the sleeve 31 and causing leakage.

[0026] At the lower end of the outer wall of the sleeve 31, an integrally formed annular extension 32 is provided along its circumference. After the sleeve 31 is completely inserted into the lower hole 41, the annular extension 32 is in close contact with the lower surface of the upper cover body 10. The outer diameter of the annular extension 32 is less than or equal to the outer diameter of the lower hole 41 of the liquid injection hole.

[0027] A chamfer is provided at the connection between the upper groove 42 and the lower hole 41 to facilitate the smooth insertion of the sleeve 31 into the lower hole 41.

[0028] In the middle of the upper top surface of the nail head 22, a cross slot 50 is provided. The cross slot 50 can be cooperated with a screwdriver to rotate the sealing nail 20.

[0029] After the liquid injection is completed, first place the sealing plug 30 into the liquid injection hole 40 so that the lower surface of the limit ring 33 is in contact with the bottom surface of the upper groove 42. Then insert the nail rod 21 into the sleeve 31. When the lower surface of the nail head 22 is in the same plane as the upper surface of the upper cover body 10, align the screwdriver with the cross slot 50 and rotate the screwdriver to make the external thread 23 and the internal thread 43 engage in a threaded manner until the nail head 22 presses the limit ring 33. At this time, the limit ring 33 is in close contact with the bottom surface of the upper groove 42 of the liquid injection hole, realizing the sealing of the liquid injection hole 40.

[0030] During the installation process, the whole sleeve 31 will expand radially outwards, and the outer diameter of the annular extension 32 also increases accordingly, so as to be in close contact with the lower surface of the upper cover body 10, further sealing the liquid injection hole 40 and also realizing the axial positioning of the sealing plug 30.

[0031] Since the nail rod 21 and the sleeve 31 are in an interference fit after the nail rod 21 is inserted into the sleeve 31, the sleeve 31 can limit the nail rod 21 axially and circumferentially through friction. Therefore, when the external thread 23 and the internal thread 43 are tightened, the sealing nail 20 is fixed axially, so that the external thread 23 and the internal thread 43 cannot rotate relative to each other, thus ensuring the reliability of the threaded connection.

[0032] When the battery works for a period of time and the electrolyte needs to be replenished due to electrolyte consumption, align the screwdriver with the cross slot 50 and rotate the sealing nail 20 to loosen the external thread 23 and the internal thread 43. Then directly pull out the sealing nail 20 from the sealing plug 30. At this time, the whole sealing plug 30 automatically contracts radially inwards, and the sealing plug 30 can be taken out from the liquid injection hole 40, so as to perform secondary liquid injection on the battery.

[0033] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above-mentioned exemplary embodiments, and the present utility model can be implemented in other forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent conditions of the claims are intended to be embraced within the present utility model. Any reference signs in the claims should not be construed as limiting the claims involved.

[0034] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A top cover plate of a lithium-ion battery capable of secondary liquid injection, comprising a top cover plate body (10); characterized in that: The vertical cross-section of the liquid injection hole (40) of the upper cover plate body (10) is T-shaped, and a detachable sealing mechanism is provided in the liquid injection hole (40). The sealing mechanism includes a sealing nail (20) and a sealing plug (30); the sealing nail (20) includes a nail rod (21) and a nail head (22); an internal thread (43) is provided on the inner side wall of the upper groove (42) of the liquid injection hole (40); a sealing plug (30) is provided in the lower hole (41) of the liquid injection hole (40); the nail head (22) is coaxially fixed to the upper end of the nail rod (21), the nail rod (21) is press-fitted into the sealing plug (30), an external thread (23) is provided on the side wall of the nail head (22), and the nail head (22) and the upper groove (42) are fixedly connected by screwing of the internal thread (43) and the external thread (23).

2. The upper cover plate of a lithium-ion battery capable of secondary liquid injection according to claim 1, characterized in that: The sealing plug (30) includes a sleeve (31) and a limiting ring (33); the limiting ring (33) is coaxially fixed to the upper end of the sleeve (31), the sleeve (31) is arranged in the lower hole (41), the lower surface of the limiting ring (33) is arranged in contact with the bottom surface of the upper groove (42), and the sleeve (31) is press-fitted on the outside of the nail rod (21).

3. A top cover plate of a lithium-ion battery capable of secondary liquid injection according to claim 2, characterized in that: The lower end of the sleeve (31) is a closed end.

4. A top cover plate of a lithium-ion battery capable of secondary liquid injection according to claim 2 or 3, characterized in that: An annular extension (32) is provided at the lower end of the outer wall of the sleeve (31). When the sleeve (31) is completely inserted into the lower hole (41), the annular extension (32) is in close contact with the lower surface of the upper cover plate body (10).

5. A top cover plate of a lithium-ion battery capable of secondary liquid injection according to claim 4, characterized in that: A chamfer is provided at the connection between the upper groove (42) and the lower hole (41).

6. The upper cover plate of a lithium-ion battery capable of secondary liquid injection according to claim 1, characterized in that: A cross opening (50) is provided in the middle of the upper top surface of the nail head (22).

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