Funnel type sealing rubber plug of lithium battery cell liquid injection port

Abstract

The utility model relates to a funnel type sealing rubber plug of a lithium battery cell liquid injection port, which comprises an annular sealing body and an elastic rubber plug funnel, the elastic rubber plug funnel is integrally arranged on the lower portion of the annular sealing body to form an elastic sealing rubber plug body, and a liquid inlet is arranged in the center of the annular sealing body. The liquid inlet is in a closed state through an elastic rubber plug funnel, the elastic rubber plug funnel is in a conical funnel shape, and a second liquid inlet is formed in the conical bottom. According to the utility model, the square battery cell liquid injection port before sealing is particularly protected, and the introduction of moisture and foreign matters into the battery cell liquid injection port in the manufacturing process is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium batteries, and in particular relates to a funnel-type sealing rubber plug for a lithium battery core liquid injection port. Background Art

[0002] Existing prismatic lithium batteries have a top cover with an inlet that is open before sealing. This open inlet creates a risk of the battery cell absorbing moisture and foreign matter during manufacturing. Excessive moisture inside the battery reacts with the electrolyte to produce hydrofluoric acid, a highly corrosive acid that can corrode and damage the positive and negative electrode materials and current collectors. Excessive moisture also reacts with the electrolyte to produce large amounts of gases (CO2, H2, CO), causing the battery to bulge. Excess moisture also catalyzes the decomposition of LiPF6 to produce more LiF and HF. Excessive LiF and HF accumulate on the surface of the SEI film, increasing the battery's internal resistance. All of these factors can affect battery performance and lifespan, and can even lead to serious safety incidents. When the internal pressure reaches a certain level, cracks develop in weak spots, causing leakage. This not only pollutes the environment, but also affects battery performance and creates safety risks. For example, the patent document with authorization announcement number CN 210628405 U discloses a sealing plug for a cover plate liquid injection port, including a reinforcing core and an elastic outer sleeve, wherein: the reinforcing core has a sealing column and a self-locking part, the self-locking part is located below the sealing column, the self-locking part has an inner side surface and a locking surface, the distance between the inner side surface and the axis of the sealing column gradually increases from bottom to top, the sealing column matches the liquid injection hole, and the locking surface conflicts with the bottom of the cover plate.

[0003] It is very necessary that the battery filling port is well sealed. Utility Model Content

[0004] The present invention aims to overcome the deficiencies in the prior art and to provide a funnel-shaped sealing rubber plug for the liquid injection port of a lithium battery cell, thereby ensuring that the cell is sealed during the manufacturing process and reducing the risk of moisture and foreign matter being introduced.

[0005] In order to achieve the above-mentioned purpose, the utility model is realized through the following technical scheme: a funnel-type sealing plug for the liquid filling port of a lithium battery cell, comprising an annular sealing body and an elastic rubber plug funnel, wherein the elastic rubber plug funnel is placed in a conical shape at the bottom of the annular sealing body to form an elastic sealing plug body, a liquid inlet is provided in the center of the annular sealing body, and the liquid inlet is in a closed state through the elastic rubber plug funnel, and the elastic rubber plug funnel is in the shape of a conical funnel, and a second liquid inlet is provided at the bottom of the cone.

[0006] Furthermore, the elastic sealing plug body is made of rubber material.

[0007] Furthermore, the annular sealing body matches the shape of the battery cell liquid inlet, and the diameter of the annular sealing body is Φ8mm-10mm.

[0008] Furthermore, the edge wall thickness of the elastic rubber plug funnel is 1mm-1.5mm.

[0009] Furthermore, the total height of the elastic sealing plug body is 8mm-12mm.

[0010] Furthermore, the diameter of the liquid inlet in the center of the annular sealing body is 5mm-7mm.

[0011] Furthermore, the diameter of the second liquid inlet after opening is 4mm-6mm, and after closing, it automatically fits into a flat shape due to its own elastic force.

[0012] Beneficial effects: Compared with the prior art, the present invention is particularly effective in protecting the square battery cell liquid injection port before sealing, thereby reducing the introduction of moisture and foreign matter into the battery cell liquid injection port during the manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of the utility model;

[0014] Figure 2 yes Figure 1 Left view of;

[0015] Figure 3 yes Figure 1 A top view of

[0016] Figure 4 This is a structural diagram of the state in which the utility model is installed on the liquid inlet of a lithium battery cell;

[0017] Figure 5 It is a schematic diagram of the structure of the liquid inlet of a lithium battery cell in the prior art.

[0018] In the figure: 1. elastic sealing plug body, 1-1. annular sealing body, 1-1-1. liquid inlet, 1-2. elastic plug funnel, 1-2-1. second liquid inlet, 1-2-2. flat closed opening, 2. battery cell body, 3. top cover, 4. liquid filling port. DETAILED DESCRIPTION

[0019] The following is a detailed description of the specific implementation method provided by the present invention in combination with the preferred embodiment: See the accompanying drawings for details. This embodiment provides a funnel-type sealing plug for the liquid injection port of a lithium battery cell, including an annular sealing body 1-1 and an elastic plug funnel 1-2. The elastic plug funnel is placed in the lower part of the annular sealing body to form an elastic sealing plug body 1. A liquid inlet 1-1-1 is provided in the center of the annular sealing body. The liquid inlet is in a closed state through the elastic plug funnel. The elastic plug funnel is in the shape of a conical funnel, and a second liquid inlet 1-2-1 is provided at the bottom of the cone.

[0020] A preferred solution of this embodiment is that the elastic sealing plug body is made of rubber material.

[0021] A preferred solution of this embodiment is that the shape of the annular sealing body matches the shape of the liquid inlet of the battery cell, and the diameter of the annular sealing body is Φ8mm-10mm.

[0022] The preferred solution of this embodiment is that the edge wall thickness of the elastic rubber plug funnel is 1mm-1.5mm. In this embodiment, the edge wall thickness of the elastic rubber plug funnel is 1mm.

[0023] The preferred solution of this embodiment is that the total height of the elastic sealing plug body is 8mm-12mm. The total height of this embodiment is 8mm.

[0024] The preferred solution of this embodiment is that the diameter of the liquid inlet in the center of the annular sealing body is 5mm-7mm. In this embodiment, the diameter of the liquid inlet is 6mm.

[0025] The preferred solution of this embodiment is that the diameter of the second liquid inlet after opening is 4mm-6mm, and after closing, it automatically adheres to the flat closed opening 1-2-2 by its own elastic force. The diameter of the second liquid inlet after opening in this embodiment is 5mm.

[0026] Working status

[0027] See attached for details Figure 5 In the prior art, the liquid injection port is open before sealing without any protective measures; the funnel-shaped rubber plug designed in this embodiment is used to seal the liquid injection port;

[0028] See attached for details Figure 1-3 2. The upper part of the rubber plug is a disc-shaped structure, which is used to fit the bottom surface of the liquid filling port;

[0029] The lower half of the rubber plug is funnel-shaped, normally closed, with a shrinkable and openable closed hole in the middle;

[0030] After the battery cell is inserted into the sealing plug, the battery cell liquid injection port is in a closed state; when liquid injection or vacuuming is required, an external introduction hose is inserted into the middle liquid inlet and the second liquid inlet of the plug until it penetrates deep into the battery cell liquid injection port; conversely, after the liquid injection and vacuuming operations are completed, the introduction tube is pulled out, and the liquid injection port plug is now in a closed state. In this embodiment, the sealing plug is inserted after the battery cell is assembled, that is, the process section after the battery cell is inserted into the sealing plug and before the subsequent sealing process avoids the introduction of external moisture and foreign matter. (The process steps are: assembly - primary helium inspection - baking - liquid injection - high temperature static - negative pressure formation - secondary liquid injection - sealing and welding)

[0031] The above-mentioned detailed description of a funnel-shaped sealing plug for a lithium battery cell liquid injection port with reference to the embodiment is illustrative rather than restrictive, and several embodiments can be listed according to the limited scope. Therefore, changes and modifications without departing from the overall concept of the present invention should fall within the scope of protection of the present invention.

Claims

1. A funnel-shaped sealing plug for a lithium battery cell liquid injection port, characterized by: It includes an annular sealing body and an elastic rubber plug funnel. The elastic rubber plug funnel is placed in the lower part of the annular sealing body to form the elastic sealing rubber plug body. A liquid inlet is provided in the center of the annular sealing body. The liquid inlet is closed by the elastic rubber plug funnel. The elastic rubber plug funnel is in the shape of a conical funnel, and a second liquid inlet is provided at the bottom of the cone.

2. The funnel-shaped sealing rubber plug for the lithium battery cell liquid injection port according to claim 1, characterized in that: The elastic sealing plug body is made of rubber material.

3. The funnel-shaped sealing plug for the lithium battery cell liquid injection port according to claim 1, characterized in that: The annular sealing body matches the shape of the liquid inlet of the battery cell, and the diameter of the annular sealing body is Φ8mm-10mm.

4. The funnel-shaped sealing rubber plug for the lithium battery cell liquid injection port according to claim 1, characterized in that: The thickness of the edge wall of the elastic rubber plug funnel is 1mm-1.5mm.

5. The funnel-shaped sealing rubber plug for the lithium battery cell liquid injection port according to claim 1 or 2, characterized in that: The total height of the elastic sealing plug body is 8mm-12mm.

6. The funnel-shaped sealing rubber plug for the lithium battery cell liquid injection port according to claim 1 or 3, characterized in that: The diameter of the liquid inlet in the center of the annular sealing body is 5mm-7mm.

7. The funnel-shaped sealing rubber plug for the lithium battery cell liquid injection port according to claim 1, characterized in that: The diameter of the second liquid inlet after opening is 4mm-6mm, and after closing, it automatically fits into a flat shape due to its own elastic force.

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