Battery cell formation negative pressure nozzle

Abstract

The utility model provides a kind of negative pressure suction nozzle of battery formation, it is related to the technical field of battery, including the suction head with first passageway and the suction nozzle with second passageway, suction head is coaxially connected with suction nozzle and makes first passageway and second passageway intercommunication, suction nozzle is provided with oval recess at one end away from suction head, and the port of second passageway is located in oval recess;The utility model can have good crystallization resistance and anticorrosive effect, can have longer service life, reduce the replacement of the application, improve convenience;The application can effectively maintain the sealing effect between the battery liquid injection port, guarantee the negative pressure state in whole negative pressure process.

Description

Technical Field

[0001] This utility model relates to the technical field of batteries, and in particular to a negative pressure suction nozzle for battery cell formation. Background Technology

[0002] Battery cells come in various shapes, commonly including blade-shaped, block-shaped, and columnar. After being immersed in electrolyte, the battery cell needs to undergo its first charge to activate the active materials within it, a process known as formation reaction, which is one of the most important steps in the lithium battery production process.

[0003] During the charging activation process, lithium ions are embedded in the surface negative electrode material. The electrolyte undergoes reduction and decomposition on the surface of the negative electrode material, generating a solid electrolyte interphase (SEI) film. This film can prevent further side reactions from occurring, thereby reducing the loss of active lithium in the lithium battery. During the formation of the solid electrolyte interphase film, gas is generated inside the cell. The gas consists of tiny bubbles that adhere to the surface of the negative electrode material. As the formation reaction proceeds, the gas increases and accumulates to form large bubbles. Under the pressure inside the cell, the large bubbles break through the gap between the separator and the electrode and accumulate in the gap between them, expanding towards the low-pressure area. When the bubbles expand to the edge and connect with the atmosphere, a stable gas overflow channel (gas path) is formed. Subsequently, the gas continuously overflows to the outside of the casing along these channels. However, gas that is not discharged in time will remain between the electrode and the diaphragm. Since gas is an insulator, it will stop the pre-formation reaction in the gas passage of the electrode, resulting in uneven formation of the electrode. In addition, the escape of the formed gas will also cause electrolyte loss. This is because the bubbles generated during the formation process will occupy part of the electrolyte space, causing the electrolyte volume to expand and overflow, resulting in electrolyte loss. Therefore, in order to reduce the residence of gas in the electrode assembly and enable it to escape quickly, a negative pressure formation process is required.

[0004] In the formation system, negative pressure (-50Kpa to 70Kpa) is required to extract the gas generated during cell formation. During the process of gas extraction, some electrolyte is also extracted. The surface of the negative pressure nozzle, which is in long-term contact with the electrolyte, is prone to electrolyte crystal formation and cross-contamination with the battery filling port. This results in the need for frequent cleaning of the negative pressure nozzle, and in severe cases, frequent replacement of the nozzle. On the other hand, it also causes the problem of difficulty in drawing negative pressure during negative pressure formation (inability to maintain pressure, causing negative pressure alarm), which seriously affects the improvement of production capacity and product quality.

[0005] This utility model is a chemical formation nozzle structure design, which mainly solves the problems of chemical formation negative pressure alarm and frequent replacement of negative pressure nozzle crystallization. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a battery cell-based negative pressure suction nozzle to solve the problem of inconvenience in using negative pressure suction nozzles.

[0007] Based on the technical problems existing in the background art, this utility model proposes a battery cell forming negative pressure suction nozzle, including a suction head with a first channel and a suction nozzle with a second channel. The suction head and the suction nozzle are coaxially connected and the first channel and the second channel are connected. An elliptical notch is provided at the end of the suction nozzle away from the suction head, and the port of the second channel is located in the elliptical notch.

[0008] In the above solution, the suction head is connected to the suction device, and the elliptical notch of the suction nozzle can connect with the liquid injection port. The slight translation of the suction nozzle will not affect the connection between the suction nozzle and the liquid injection port, and can always meet the sealing effect around the suction nozzle, thereby maintaining the negative pressure.

[0009] Preferably, a breathable and waterproof membrane is provided at the connection between the first channel and the second channel.

[0010] In the above scheme, the function of the breathable and waterproof membrane layer is to allow air to pass through while isolating liquid. This is mainly to effectively remove the gas generated during the negative pressure extraction process, thereby avoiding the negative pressure extraction of too much electrolyte, which would cause abnormalities at the formation interface and affect the electrical performance of the battery cell.

[0011] Preferably, the first channel is coaxial with the suction head, and the second channel is coaxial with the first channel.

[0012] The above design aims to place the first channel at the center of the suction head and the second channel at the center of the suction nozzle, so that the suction nozzle can quickly connect with the battery cell filling port.

[0013] Preferably, the nozzle has a racetrack-shaped cross-section, and the line connecting the longer axis of symmetry of the nozzle cross-section and the focal point of the elliptical notch is parallel to each other.

[0014] In this design, the racetrack-shaped nozzle facilitates the installation of an elliptical notch, preventing the tip edge from being too thin. When the nozzle is aligned with the injection port, the area around the injection port is completely covered, thus maintaining a tight seal between the injection port and the nozzle.

[0015] Preferably, the end of the suction head away from the nozzle is provided with a limiting notch that communicates with the first channel.

[0016] In the above scheme, the limiting notch set in the first channel is for the installation and use of negative pressure equipment, which requires the device in this application to maintain a specific direction and angle to avoid misalignment during use.

[0017] Preferably, the side of the nozzle away from the suction head is coated with polytetrafluoroethylene.

[0018] In the above solution, the surface treatment of polytetrafluoroethylene can improve anti-adhesion and reduce the probability of crystallization on the nozzle surface, thereby reducing the need for replacement of this application and saving costs.

[0019] Preferably, the suction head is made of polyphenylene sulfide or polyether ether ketone, and the suction nozzle is made of fluororubber or perfluoroether rubber.

[0020] In the above solution, the suction nozzle and suction head in this application are made of rubber. During use, the suction nozzle has a certain deformation capability. When the suction nozzle is connected to the liquid injection port of the battery cell, it can maintain a seal with the liquid injection port through deformation. At the same time, the above materials have good corrosion resistance.

[0021] Compared with the prior art, the negative pressure suction nozzle for battery cell formation proposed in this utility model adopts the above-mentioned technical solution and achieves the following technical effects:

[0022] This invention has good anti-crystallization and anti-corrosion effects, a long service life, reduces the need for replacement, and improves convenience; this invention can effectively maintain the sealing effect between the battery cell and the electrolyte filling port, ensuring the negative pressure state throughout the entire negative pressure process. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ;

[0024] Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ;

[0025] Figure 3 This is a schematic diagram of the internal structure of this utility model.

[0026] In the diagram: 11. First channel; 1. Suction head; 21. Second channel; 2. Suction nozzle; 22. Oval notch; 3. Breathable and waterproof membrane; 12. Limiting notch. Detailed Implementation

[0027] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0028] Example

[0029] Please refer to Figures 1-3This utility model proposes a negative pressure suction nozzle 2 for battery cell formation, including a suction head 1 with a first channel 11 and a suction nozzle 2 with a second channel 21. The suction head 1 and the suction nozzle 2 are coaxially connected, and the first channel 11 and the second channel 21 are connected. An elliptical notch 22 is provided at the end of the suction nozzle 2 away from the suction head 1, and the port of the second channel 21 is located in the elliptical notch 22. In this solution, it is necessary to connect this application with a negative pressure device. One end of the suction head 1 is connected to the negative pressure device, and one end of the suction nozzle 2 corresponds to the liquid injection port of the battery cell. The air bubbles generated in the battery cell are adsorbed by negative pressure. The elliptical notch 22 of the suction nozzle 2 can also be changed to a slightly larger circular notch, which can also ensure a good sealing effect.

[0030] In specific implementation, refer to Figure 3 A breathable and waterproof membrane 3 is provided at the connection between the first channel 11 and the second channel 21. In this application, the breathable and waterproof membrane 3 between the first channel 11 and the second channel 21 is a membrane with a small mesh gap in the prior art, which can only allow gas to pass through and can effectively prevent liquid from entering the negative pressure device.

[0031] In specific implementation, refer to Figure 3 The first channel 11 is coaxial with the suction head 1, and the second channel 21 is coaxial with the first channel 11. In this solution, the suction head 1 and the suction nozzle 2 are integrated. When manufacturing this application, the coaxiality of the first channel 11 and the second channel 21 can facilitate production and reduce production costs.

[0032] In specific implementation, refer to Figure 3 The nozzle 2 has a racetrack-shaped cross section. The longer axis of symmetry of the nozzle 2 cross section is parallel to the line connecting the focal point of the elliptical recess 22. The nozzle 2 cross section in this application can also be other shapes. After the elliptical recess 22 is opened, the edge of the elliptical recess 22 is made thick enough to prevent excessive deformation during use, which would lead to poor sealing effect.

[0033] In specific implementation, refer to Figure 3 The end of the suction head 1 away from the nozzle 2 is provided with a limiting notch 12 that communicates with the first channel 11. In this application, the limiting notch 12 is used to limit the position of the suction head 1 relative to the negative pressure mechanism, so as to prevent the suction head 1 from rotating relative to the negative pressure device, thereby affecting the sealing effect of the nozzle 2 and the battery cell liquid injection port.

[0034] In specific implementation, refer to Figure 3 The side of the nozzle 2 away from the suction head 1 is treated with polytetrafluoroethylene (PTFE) coating. In this application, PTFE can be coated with a film on the surface of the nozzle 2, which has good hydrophobicity and corrosion resistance, and can cope with the crystallization and corrosion effects of electrolyte in the battery cell, thereby improving the durability of this application.

[0035] In specific implementation, refer to Figure 3 The suction head 1 and the nozzle 2 are made of rubber; the suction head 1 is made of polyphenylene sulfide or polyether ether ketone, and the nozzle 2 is made of fluororubber or perfluoroether rubber; in this application, the rubber has a certain elasticity and can maintain good sealing with the battery cell filling port during use.

[0036] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A battery cell forming negative pressure suction nozzle, characterized in that, It includes a suction head (1) with a first channel (11) and a suction nozzle (2) with a second channel (21). The suction head (1) and the suction nozzle (2) are coaxially connected and the first channel (11) and the second channel (21) are connected. The end of the suction nozzle (2) away from the suction head (1) is provided with an elliptical notch (22), and the port of the second channel (21) is located in the elliptical notch (22).

2. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, A breathable and waterproof membrane (3) is provided at the connection between the first channel (11) and the second channel (21).

3. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, The first channel (11) is coaxial with the suction head (1), and the second channel (21) is coaxial with the first channel (11).

4. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, The cross-section of the suction nozzle (2) is racetrack shaped, and the longer axis of symmetry of the suction nozzle (2) is parallel to the line connecting the focal point of the elliptical notch (22).

5. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, The end of the suction head (1) away from the nozzle (2) is provided with a limiting notch (12) that communicates with the first channel (11).

6. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, The side of the nozzle (2) away from the suction head (1) is coated with polytetrafluoroethylene.

7. The negative pressure suction nozzle for cell formation according to claim 1, characterized in that, The suction head (1) is made of polyphenylene sulfide or polyether ether ketone, and the suction nozzle (2) is made of fluororubber or perfluoroether rubber.

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