Battery cell liquid injection device and battery cell liquid injection method

Abstract

The embodiment of the present application provides an electric core liquid injection device and an electric core liquid injection method. It relates to the technical field of batteries. The electric core liquid injection device comprises a docking piece, a liquid injection piece and a gas extraction piece. The docking piece has a first docking end and a second docking end. The first docking end is used for communicating with a liquid storage cavity of an electric core. The liquid injection piece is connected to the second docking end of the docking piece. The gas extraction piece is connected to the second docking end of the docking piece. When the electric core liquid injection device is in a vacuum state, the gas extraction piece is communicated with the liquid storage cavity of the electric core through the docking piece. When the electric core liquid injection device is in a liquid injection state, the liquid injection piece is communicated with the liquid storage cavity of the electric core through the docking piece. When the electric core liquid injection device is in a non-liquid injection and non-vacuum state, the first docking end is closed. The gas extraction piece and the liquid injection piece are disconnected from the liquid storage cavity of the electric core. The electric core liquid injection device and the electric core liquid injection method provided by the embodiment of the present application improve the uniformity of the electrolyte in the electric core and improve the use performance of the electric core.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and more particularly to a battery cell liquid injection device and a battery cell liquid injection method. Background Technology

[0002] The chemical reactions inside a battery require the transfer of ions between the electrodes and the electrolyte; therefore, the choice and concentration of the electrolyte are crucial to battery performance. The electrolyte filling process brings the battery cell into contact with the electrolyte, allowing the electrolyte to fully penetrate the electrode structure and form the electrolyte medium needed for the chemical reactions.

[0003] In related technologies, electrolyte impregnation methods for battery cells include vacuum chamber pressurized impregnation, breathing impregnation, and stepped impregnation. Vacuum chamber pressurized impregnation refers to: after purging air from the gap between the positive and negative electrodes, adding a pre-mixed electrolyte into the battery cell. Breathing impregnation refers to: evacuating the battery casing; then maintaining pressure on the battery casing, injecting electrolyte, then depressurizing the battery casing; and then continuing the cycle of pressurization, depressurization, vacuuming, and depressurization followed by a period of settling.

[0004] However, existing battery cells suffer from poor electrolyte wetting. Summary of the Invention

[0005] This application provides a battery cell electrolyte injection device and a battery cell electrolyte injection method, which improves the uniformity of electrolyte wetting in the battery cell and improves the performance of the battery cell.

[0006] In a first aspect, embodiments of this application provide a battery cell liquid injection device, which includes a docking part, a liquid injection part, and a vacuuming part.

[0007] The connector has a first mating end and a second mating end. The first mating end is used to communicate with the electrolyte reservoir of the battery cell.

[0008] The injection fitting is connected to the second mating end of the mating fitting.

[0009] The air extraction component is connected to the second mating end of the mating component.

[0010] When the cell liquid injection device is in a vacuum state, the vacuuming component is connected to the cell's liquid storage chamber through the docking component. The liquid injection component is disconnected from the cell's liquid storage chamber.

[0011] When the cell liquid injection device is in the liquid injection state, the liquid injection component is connected to the cell's liquid storage chamber through the docking component. The air extraction component is disconnected from the cell's liquid storage chamber.

[0012] When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the air extraction component is disconnected from the cell's liquid storage chamber; the liquid injection component is disconnected from the cell's liquid storage chamber.

[0013] In some embodiments of this application, the docking component includes a first docking component and a second docking component.

[0014] The first docking part is connected to the liquid injection part and the air extraction part.

[0015] The second docking component is used to connect with the battery cell, and a normally closed shut-off valve is provided in the second docking component.

[0016] When the battery cell liquid injection device is in a vacuum state, the normally closed shut-off valve is open, and the first and second docking parts are connected. The vacuum pump is connected to the battery cell's liquid storage chamber through the first and second docking parts. The liquid injection device is disconnected from the battery cell's liquid storage chamber.

[0017] When the battery cell liquid injection device is in the liquid injection state, the normally closed shut-off valve is in the open state, and the first and second docking parts are connected. The liquid injection component is connected to the liquid storage chamber of the battery cell through the first and second docking parts. The air extraction component is disconnected from the liquid storage chamber of the battery cell.

[0018] When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the normally closed shut-off valve is in the open state, and the first and second docking parts are disconnected. The air extraction component is disconnected from the cell's liquid storage chamber; the liquid injection component is disconnected from the cell's liquid storage chamber.

[0019] In some embodiments of this application, the docking component includes a valve body and a valve core. The valve body cavity has a first channel, a second channel, and a third channel. A first end of the first channel is connected to a liquid injection component. A first end of the second channel is connected to a vacuum component. A first end of the third channel is used to communicate with the liquid storage chamber of the battery cell.

[0020] The valve core is movable within the cavity, and it switches between the first position, the neutral position, and the second position.

[0021] When the valve core is in the first position, the second end of the first channel is connected to the second end of the third channel, and the second end of the second channel is disconnected from the second end of the third channel, forming the liquid injection state of the cell liquid injection device.

[0022] When the valve core is in the second position, the second end of the second channel is connected to the second end of the third channel, and the second end of the first channel is disconnected from the second end of the third channel, forming a vacuum state for the cell liquid injection device.

[0023] When the valve core is in the neutral position, the second end of the second channel and the second end of the third channel are disconnected, and the second end of the first channel and the second end of the third channel are disconnected, forming a non-liquid injection and non-vacuum state of the cell liquid injection device.

[0024] In some embodiments of this application, the cell liquid injection device further includes a liquid injection needle, the first end of which is connected to the liquid storage chamber of the cell, and the second end of which is connected to the first docking end.

[0025] In some embodiments of this application, the cell liquid injection device further includes a base having a support platform for placing the cell.

[0026] In some embodiments of this application, the base further includes a clamping section located on the support platform, and the clamping end of the clamping section forms a clamping area for clamping and fixing the battery cell.

[0027] In some embodiments of this application, the cell liquid injection device further includes a liquid injection pipeline, a first end of which is connected to a liquid injection component, a second end of which is connected to a docking component, and a liquid injection valve is provided on the liquid injection pipeline.

[0028] In some embodiments of this application, the cell liquid injection device further includes an air extraction pipeline, a first end of which is connected to an air extraction component, a second end of which is connected to a docking component, and an air extraction valve is provided on the air extraction pipeline.

[0029] Secondly, embodiments of this application provide a cell liquid injection method, applied to a cell liquid injection device, the cell liquid injection method comprising:

[0030] A vacuum chamber in the battery cell is evacuated using a vacuum pump.

[0031] Once the vacuuming is complete, the vacuuming component and the liquid storage chamber of the battery cell are disconnected.

[0032] Liquid is injected into the reservoir of the battery cell using a liquid injection device;

[0033] Once the liquid injection is complete, the liquid injection component and the liquid storage chamber of the battery cell are disconnected.

[0034] In some embodiments of this application, a vacuum pump is used to evacuate the liquid storage chamber of the battery cell; after the evacuation of the battery cell is completed, the vacuum pump and the liquid storage chamber of the battery cell are disconnected; it also includes:

[0035] When the vacuum level of the battery cell's liquid storage chamber is less than the preset vacuum level, the vacuum pump and the battery cell's liquid storage chamber are disconnected; the first docking end of the battery cell's liquid injection device is closed.

[0036] The preset vacuum degree is P, and P satisfies: P≤300Pa.

[0037] In some embodiments of this application, when the vacuum level of the liquid storage chamber of the battery cell is less than a preset vacuum level, the vacuum pump and the liquid storage chamber of the battery cell are disconnected; the first docking end of the docking member of the battery cell liquid injection device is closed; and it further includes:

[0038] Within a preset time period, when the preset vacuum level P satisfies: P≤300Pa, the pumping unit and the liquid storage chamber of the battery cell are disconnected; the first docking end of the docking unit is closed.

[0039] In some embodiments of this application, when the vacuum level of the liquid storage chamber of the battery cell is less than a preset vacuum level, the vacuum pump and the liquid storage chamber of the battery cell are disconnected; the first docking end of the docking member of the battery cell liquid injection device is closed; and it further includes:

[0040] Within a preset time period, when the change in the vacuum level of the battery cell is less than or equal to 1 Pa / s, the electrolyte filling port of the battery cell is closed.

[0041] In some embodiments of this application, the preset vacuum degree P satisfies: 30Pa≤P≤70Pa.

[0042] In some embodiments of this application, the preset time period is T, where T satisfies: T≥10s.

[0043] The battery cell liquid injection device and method provided in this application embodiment perform the vacuuming and liquid injection processes of the battery cell in separate steps, which is beneficial for balancing the production line cycle and greatly improves the efficiency of the battery cell vacuuming, electrolyte injection, and electrolyte wetting processes. Simultaneously, the battery cell liquid injection method provided in this application embodiment closes the first docking end to seal the battery cell's liquid storage cavity after the vacuuming process and closes the first docking end to seal the battery cell's liquid storage cavity after the electrolyte injection process. This ensures that the battery cell is isolated from the external environment after each process, preventing external air or impurities from entering the battery cell's liquid storage cavity and hindering the subsequent electrolyte wetting process. Compared with the prior art, the battery cell liquid injection device and method provided in this application embodiment reduce the resistance of the electrolyte during wetting in the battery cell's liquid storage cavity, improve the consistency of electrolyte wetting, avoid problems such as black spots and lithium plating during battery cell formation, and improve the performance of the battery cell. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0045] Figure 1 A schematic diagram of the structure of the cell liquid injection device provided in the embodiments of this application. Figure 1 ;

[0046] Figure 2 A schematic diagram of the structure of the cell liquid injection device provided in the embodiments of this application. Figure 2 ;

[0047] Figure 3 This is a schematic diagram of the base and battery cell from a first-view perspective, provided in an embodiment of this application.

[0048] Figure 4 This is a schematic diagram of the base and battery cell from a second perspective, provided in an embodiment of this application.

[0049] Figure 5This is a structural schematic diagram of the base and battery cell from a third-view perspective, provided in an embodiment of this application.

[0050] Figure 6 This is a schematic diagram of the cell liquid injection method provided in the embodiments of this application.

[0051] Explanation of reference numerals in the attached figures:

[0052] 100: Connecting part; 110: First connecting part; 120: Second connecting part;

[0053] 200: Injection part; 210: Injection pipeline;

[0054] 300: Extraction unit; 310: Extraction piping;

[0055] 400: Base; 410: Clamping section;

[0056] 500: Injection needle;

[0057] 600: Battery cell. Detailed Implementation

[0058] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0059] The battery cell is the core component of a battery, responsible for storing and releasing electrical energy. A battery cell includes a positive electrode, a negative electrode, an electrolyte, and a separator. The positive electrode material is the main component that stores lithium ions or other ions. The negative electrode material is another component that stores lithium ions or other ions. The electrolyte is the medium for ion conduction in the battery, ensuring ion transport between the positive and negative electrodes. The separator is a porous membrane placed between the positive and negative electrodes, preventing direct contact between the electrodes that could cause a short circuit, while allowing ions to pass through. Additionally, the current collector is a conductive material used to collect and conduct current, connecting the positive and negative electrodes respectively. Conductive agents are added to the electrode materials to improve conductivity. A binder is used to bond the electrode materials to the current collector.

[0060] Taking a lithium-ion battery as an example, the battery's working process is as follows: Charging process: When an external power source applies voltage, lithium ions are released from the positive electrode, migrate through the electrolyte to the negative electrode, and embed themselves in the negative electrode material. Discharging process: Lithium ions are released from the negative electrode, migrate through the electrolyte to the positive electrode, and embed themselves in the positive electrode material, generating current for use by the external circuit.

[0061] The wetting of the electrolyte within the battery cell is crucial to battery performance and lifespan. Good wetting ensures that the electrolyte fully contacts the surface of the electrode materials, thereby maximizing the active area of ​​the electrodes. This contributes to improved battery capacity and efficiency.

[0062] The wetting and diffusion mechanism of electrolyte within a battery cell is mainly determined by three factors: electrolyte flow pressure, capillary forces generated by material properties, and air resistance hidden in material pores. The electrolyte flow pressure is consistent across all cells because it remains essentially stationary after electrolyte injection. The capillary forces generated by material properties are unique, determined by the preceding processes. Therefore, a universally applicable improvement to the electrolyte injection wetting process lies in addressing the air resistance hidden in the electrode material pores. Numerous studies have found that air resistance directly creates wetting dead zones in the later stages of wetting, leading to problems such as black spots and lithium plating at the electrode interface during subsequent formation.

[0063] In related technologies, the wetting of electrolyte inside the battery cell mainly takes the following forms: 1. Implanting and venting the battery cell in a high-pressure chamber under normal pressure. 2. Stepped negative pressure wetting inside the battery cell: After electrolyte injection, the battery cell is left to stand at a preset temperature for a certain period of time; at the preset temperature, the battery cell is evacuated multiple times, and left to stand for a certain period of time after each evacuation. During the multiple evacuations, the vacuum pressure inside the battery cell changes stepwise from high to low, and the wetted battery cell is then sealed. 3. Breathing negative pressure wetting inside the battery cell: Vacuuming is performed inside the battery casing; pressure is maintained; electrolyte is injected; pressure is released; the following cycle of pressurization, pressure release, evacuation, and pressure release is performed: nitrogen gas at a pressure of 0.020~0.035MPa is introduced for 60~80s, pressure is released, vacuuming is performed to a vacuum degree of -65KPa~-90KPa, pressure is released; nitrogen gas is introduced and maintained for 30~80s; pressure is released, thus completing the electrolyte injection.

[0064] However, traditional impregnation methods, such as vacuum chamber pressurized impregnation, breathing impregnation, and stepped impregnation, have drawbacks such as slow impregnation speed, long process time, complex process, and expensive equipment. In particular, the process of drawing negative pressure again after electrolyte injection leaves the battery cell in a gas-liquid mixed state. Although this has an effect on improving battery impregnation, the negative pressure will carry out electrolyte due to the influence of the gas-liquid mixed phase, and there is liquid-sealed air that cannot escape, so the impregnation consistency cannot be guaranteed.

[0065] Therefore, embodiments of this application provide a battery cell liquid injection device and a battery cell liquid injection method. The battery cell liquid injection device includes a docking member, an injection member, and a vacuum member. The docking member has a first docking end and a second docking end. The first docking end is used to communicate with the liquid storage chamber of the battery cell. The injection member is connected to the second docking end of the docking member. The vacuum member is connected to the second docking end of the docking member.

[0066] When the battery cell liquid injection device is in a vacuum state, the docking parts are in a docked state, with the first and second docking ends connected. The vacuuming component is connected to the battery cell's liquid storage chamber through the docking parts. The liquid injection component is disconnected from the battery cell's liquid storage chamber.

[0067] When the battery cell liquid injection device is in the liquid injection state, the docking parts are in the docking state, with the first docking end and the second docking end connected. The liquid injection component is connected to the liquid storage chamber of the battery cell through the docking parts. The air extraction component is disconnected from the liquid storage chamber of the battery cell.

[0068] When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the air extraction component is disconnected from the cell's liquid storage chamber; the liquid injection component is disconnected from the cell's liquid storage chamber.

[0069] The battery cell liquid injection device and method provided in this application embodiment perform the battery cell vacuuming and liquid injection processes in separate steps, which is beneficial for production line cycle balance and greatly improves the efficiency of the battery cell vacuuming, electrolyte injection, and electrolyte wetting processes. Simultaneously, the battery cell liquid injection method provided in this application embodiment closes the first docking end to seal the battery cell's liquid storage cavity after the vacuuming process and closes the first docking end to seal the battery cell's liquid storage cavity after the electrolyte injection process. This ensures that the battery cell is isolated from the external environment after each process, preventing external air or impurities from entering the battery cell's liquid storage cavity and hindering the subsequent electrolyte wetting process. Compared with related technologies, the battery cell liquid injection device and method provided in this application embodiment reduce the resistance of electrolyte wetting in the battery cell's liquid storage cavity, improve the consistency of electrolyte wetting, avoid problems such as black spots and lithium plating during battery cell formation, and improve the battery cell's performance.

[0070] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0071] Firstly, referring to Figure 1 and Figure 2 This application provides a battery cell liquid injection device, which includes a docking part 100, a liquid injection part 200, and a vacuuming part 300.

[0072] The docking component 100 has a first docking end and a second docking end. The first docking end is used to communicate with the liquid storage chamber of the battery cell 600.

[0073] The vacuum pump 300 is connected to the second docking end of the docking member 100. The vacuum pump 300 is used to evacuate the liquid storage chamber of the battery cell 600.

[0074] The injection unit 200 is connected to the second docking end of the docking unit 100. The injection unit 200 is used to inject electrolyte into the storage chamber of the cell 600.

[0075] When the cell liquid injection device is in a vacuum state, the docking member 100 is in a docked state, with the first docking end and the second docking end connected. The vacuum pump 300 is connected to the liquid storage chamber of the cell 600 through the docking member 100. The liquid injection member 200 is disconnected from the liquid storage chamber of the cell 600. When the vacuum pump 300 evacuates the liquid storage chamber of the cell 600, the first docking end and the second docking end are connected. In this way, the vacuum pump 300 can directly connect to the liquid storage chamber of the cell 600, thereby efficiently extracting air or other gases from the liquid storage chamber. This helps to create a low-pressure environment in the liquid storage chamber, preparing for the subsequent liquid injection process.

[0076] When the cell electrolyte filling device is in the filling state, the docking member 100 is in the docking state, and the first docking end and the second docking end are connected. The filling member 200 is connected to the electrolyte storage chamber of the cell 600 through the docking member 100. The degassing member 300 is disconnected from the electrolyte storage chamber of the cell 600. In this way, when the filling member 200 injects electrolyte into the electrolyte storage chamber of the cell 600, the first docking end and the second docking end are connected, ensuring that the electrolyte can be accurately delivered to the electrolyte storage chamber of the cell 600. This precise control helps to improve the consistency and quality of battery production and reduce battery performance problems caused by improper electrolyte filling.

[0077] When the cell filling device is in a non-filling and non-vacuuming state, the first docking end is closed. The vacuum component 300 is disconnected from the electrolyte storage chamber of the cell 600; the filling component 200 is also disconnected from the electrolyte storage chamber of the cell 600. Thus, when the cell filling device is in a non-filling and non-vacuuming state, closing the first docking end ensures that the electrolyte storage chamber of the cell 600 is in a closed state. The closed state of the electrolyte storage chamber of the cell 600 means that the electrolyte storage chamber is not connected to the outside atmosphere. When the electrolyte storage chamber of the cell 600 is in a closed state, it is isolated from the outside air environment, preventing outside air from re-entering the battery's electrolyte storage chamber and avoiding gases in the cell 600 from hindering the electrolyte wetting process, thereby improving the uniformity of electrolyte wetting inside the cell 600. Furthermore, this design helps prevent liquid leakage and the entry of outside gases into the storage chamber, ensuring the stability and safety of the cell 600's electrolyte storage chamber.

[0078] As one feasible implementation method, refer to Figures 3 to 5 The battery cell injection device also includes a base 400 with a support platform for placing the battery cell 600. The support platform provides a stable placement for the battery cell 600, preventing operational instability caused by vibration or movement during injection or vacuuming. This helps ensure the accuracy and consistency of the injection process.

[0079] As one feasible implementation, the base 400 also includes a clamping section 410 located on the support platform. The clamping end of the clamping section 410 forms a clamping area for clamping and fixing the battery cell 600, ensuring the stability of the battery cell 600 during electrolyte injection. This helps improve the accuracy of electrolyte injection and avoids uneven or incorrect injection caused by movement of the battery cell 600. By clamping the battery cell 600, the risk of accidental drops or movement is reduced, significantly improving operational safety, especially when handling flammable, explosive, or corrosive electrolytes.

[0080] As one feasible implementation, the cell liquid injection device also includes a vacuum line 310, the first end of which is connected to the vacuum component 300, the second end of which is connected to the docking component 100, and a vacuum valve is provided on the vacuum line 310.

[0081] For example, the vacuum pump 300 can be a vacuum pump. In this way, when the cell filling device is in the filling state, the cell 600's liquid storage chamber is a vacuum environment. The vacuum environment can effectively reduce the formation of bubbles in the electrolyte, ensure that the electrolyte can fully wet the electrode materials, and improve the battery's performance and consistency.

[0082] By installing an air extraction valve on the air extraction pipeline 310, the air extraction valve can precisely control the opening and closing of the air extraction component 300, thereby precisely controlling the pressure changes inside the battery cell 600.

[0083] As one feasible implementation, the cell electrolyte injection device further includes an injection line 210, with a first end connected to the injection component 200 and a second end connected to the docking component 100. An injection valve is installed on the injection line 210. By providing the injection line 210 and the injection valve, the opening and closing of the injection component 200 can be precisely controlled, thereby precisely controlling the electrolyte flow rate and injection time. This precise control helps ensure consistent electrolyte injection volume for each cell 600, improving product consistency and quality.

[0084] For example, the electrolyte injection unit 200 includes an injection tank and an injection pump. The outlet of the injection tank is connected to the inlet of the injection pump body, and the outlet of the injection pump body is connected to the injection valve and the docking part 100. The injection tank provides a stable source of electrolyte storage and supply, ensuring a continuous and stable supply of electrolyte during the injection process and avoiding injection interruptions caused by unstable supply. The injection pump can precisely control the flow rate and pressure of the electrolyte, ensuring the accuracy and consistency of each injection. The injection valve remains closed when not in the injection state to prevent electrolyte backflow and contamination, ensuring the cleanliness and safety of the injection tank. The injection pump can quickly deliver electrolyte to the battery cell 600, improving the injection speed and efficiency to meet the needs of large-scale production.

[0085] The electrolyte filling device also includes a stirrer, the stirring end of which is located in the filling chamber of the filling tank. Through continuous mechanical agitation, the stirrer effectively breaks down and reduces air bubbles in the electrolyte. The stirring action causes bubbles to rise to the liquid surface and escape, thereby reducing the bubble content in the electrolyte. By maintaining the fluidity of the liquid, the stirrer prevents bubbles from accumulating in any one area, thus reducing bubble formation and growth. The liquid flow and turbulence generated by stirring help bring bubbles to the liquid surface, making it easier for them to escape into the atmosphere.

[0086] The stirring element, through its rotation or vibration, can uniformly mix the various components in the electrolyte, preventing component separation or precipitation. This ensures that the electrolyte composition is consistent with each injection.

[0087] The agitator also helps to evenly distribute the temperature in the electrolyte, preventing localized overheating or undercooling, which is especially important for certain temperature-sensitive electrolyte components. Through continuous agitation, the components in the electrolyte remain in a dynamic equilibrium, ensuring that the chemical and physical properties of the electrolyte remain consistent during the injection process.

[0088] For example, the mixing element includes a stirring rod.

[0089] As one possible implementation, the docking member 100 includes a first docking member 110 and a second docking member 120.

[0090] The first docking part 11v is connected to the liquid injection part 200 and the air extraction part 300.

[0091] The second docking part 120 is used to connect with the battery cell 600, and a normally closed shut-off valve is provided in the second docking part 120.

[0092] When the cell liquid injection device is in a vacuum state, the normally closed shut-off valve is open, and the first docking member 110 and the second docking member 120 are connected. The vacuum pump 300 is connected to the liquid storage chamber of the cell 600 through the first docking member 110 and the second docking member 120. The liquid injection member 200 is disconnected from the liquid storage chamber of the cell 600 to prevent liquid from entering the vacuum system.

[0093] When the cell liquid injection device is in the liquid injection state, the normally closed shut-off valve is in the open state, and the first docking member 110 and the second docking member 120 are connected. The liquid injection member 200 is connected to the liquid storage chamber of the cell 600 through the first docking member 110 and the second docking member 120. The air extraction member 300 is disconnected from the liquid storage chamber of the cell 600.

[0094] When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the normally closed shut-off valve is in the open state, and the first docking part 110 and the second docking part 120 are disconnected. The first docking end is closed. The vacuum component 300 is disconnected from the liquid storage chamber of the cell 600; the liquid injection component 200 is disconnected from the liquid storage chamber of the cell 600. Both the vacuum component 300 and the liquid injection component 200 are disconnected from the liquid storage chamber to ensure the sealing and safety of the liquid storage chamber.

[0095] A normally closed gate valve is a type of valve that is closed by default and only opens when an external force (such as mechanical, pneumatic, hydraulic, or electric actuation) is applied. This design ensures that the valve remains closed when there is no external operation, thus preventing accidental flow of fluids or gases.

[0096] In non-liquid-filled and non-vacuum-emptied states, the normally closed shut-off valve remains closed, forming an effective seal, reducing the risk of leakage, and ensuring the integrity and safety of the cell liquid-filling device.

[0097] Normally closed shut-off valves can be quickly opened or closed using simple external controls (such as manual, pneumatic, or electric drive), simplifying the operation process and improving production efficiency.

[0098] By incorporating a normally closed shut-off valve in the second docking component 120, the valve automatically closes when not in liquid injection or vacuuming mode, ensuring the sealing of the electrolyte storage chamber of the battery cell 600 and preventing the entry of external air or impurities. This avoids external air or impurities hindering the electrolyte wetting process. Controlling the closure of the normally closed shut-off valve allows for rapid switching between liquid injection and vacuuming functions, simplifying these processes and improving work efficiency. Simultaneously, when the battery cell liquid injection device is in either liquid injection or vacuuming mode, only one of the injection component 200 or the vacuuming component 300 is connected to the electrolyte storage chamber of the battery cell 600, preventing cross-contamination between the injection component 200 and the vacuuming component 300 and improving the cleanliness of the battery cell liquid injection device.

[0099] For example, the first mating member 110 can be a mating connector, and the second mating member 120 can be a mating connector.

[0100] In one feasible implementation, the docking component 100 includes a valve body and a valve core. The valve body cavity has a first channel, a second channel, and a third channel. The first end of the first channel is connected to the liquid injection component 200. The first end of the second channel is connected to the air extraction component 300. The first end of the third channel is used to communicate with the liquid storage chamber of the battery cell 600.

[0101] The valve core is movable within the cavity, switching between a first position, a neutral position, and a second position. By switching the valve core between different positions, the transition between liquid injection, vacuuming, and non-liquid injection / vacuuming states can be quickly achieved, simplifying the operation of the cell liquid injection device and improving work efficiency.

[0102] When the valve core is in the first position, the second end of the first channel is connected to the second end of the third channel, and the second end of the second channel is disconnected from the second end of the third channel, forming the liquid injection state of the cell liquid injection device.

[0103] The second end of the first channel is connected to the second end of the third channel, allowing the injection unit 200 to inject electrolyte into the storage chamber of the cell 600 through the first channel. The second end of the second channel is disconnected from the second end of the third channel to ensure that the suction unit 300 is isolated from the storage chamber and to avoid interfering with the injection process.

[0104] When the valve core is in the second position, the second end of the second channel is connected to the second end of the third channel, and the second end of the first channel is disconnected from the second end of the third channel, forming a vacuum state for the cell liquid injection device.

[0105] The second end of the second channel is connected to the second end of the third channel, allowing the suction device 300 to communicate with the liquid storage chamber through the second channel, thereby extracting the gas from the liquid storage chamber. The second end of the first channel is disconnected from the second end of the third channel, ensuring that the liquid injection device 200 is isolated from the liquid storage chamber, preventing electrolyte from entering the liquid storage chamber of the cell 600.

[0106] During liquid injection and vacuuming, only one function is connected to the liquid storage chamber, avoiding cross-contamination between the two and improving the purity and reliability of the operation.

[0107] When the valve core is in the neutral position, the second end of the second channel and the second end of the third channel are disconnected, as are the second ends of the first channel and the second ends of the third channel, forming a non-liquid-filling and non-vacuum-evacuation state of the cell liquid injection device. In this state, the liquid storage chamber is disconnected from both the liquid injection component 200 and the air extraction component 300, ensuring the sealing and safety of the liquid storage chamber and preventing the entry of external air or impurities.

[0108] For example, the docking component 100 can be a three-way three-position valve. A three-way three-position valve has three channels and three operating positions, enabling flexible flow direction management in a fluid control system. Because it can perform multiple functions within a single valve body, the three-way three-position valve can reduce the number of valves required in a battery cell filling device, thereby simplifying the design of the battery cell filling device and reducing complexity and cost.

[0109] The battery cell 600 has an injection port. The injection port of the battery cell 600 is used to connect with the injection component 200. Thus, the injection component 200 injects electrolyte into the storage chamber of the battery cell 600 through the injection port. Simultaneously, the injection port of the battery cell 600 is also used to connect with testing equipment, such as pressure testing equipment or leak detectors. That is to say, in addition to its use by the injection component 200 to inject electrolyte into the storage chamber and by the vacuum component 300 to evacuate the storage chamber, the injection port of the battery cell 600 also needs to connect with other components. To achieve versatility in connecting the battery cell 600 through the injection port, the battery cell injection device provided in this embodiment also includes an injection needle 500.

[0110] As one feasible implementation, the cell liquid injection device further includes a liquid injection needle 500, the first end of which is connected to the liquid storage chamber of the cell 600, and the second end of which is connected to the first docking end.

[0111] The injection needle 500 serves as a standardized interface, enabling the cell 600's injection port to be flexibly connected to various devices, such as testing equipment. This versatility reduces the need for different interface adapters and simplifies the operation process.

[0112] The injection needle 500 is typically designed to fit tightly with the injection port, providing a good seal. This helps prevent electrolyte leakage and the ingress of outside air, improving the safety and reliability of the cell 600.

[0113] By using the injection needle 500, operators can more easily switch between different devices, reducing the complexity of connection and disconnection. This not only improves operational efficiency but also reduces maintenance difficulty. Since the injection needle 500 can be used as a replaceable interface component, direct wear on the injection port of the battery cell 600 body is reduced, thereby extending the service life of the battery cell 600.

[0114] Secondly, referring to Figure 6 This application provides a method for injecting electrolyte into a battery cell, applied to a battery cell electrolyte injection device. The method includes:

[0115] S100: A vacuum device is used to evacuate the liquid storage chamber of the battery cell;

[0116] S200: After the vacuuming is completed, the vacuuming component and the liquid storage chamber of the battery cell are disconnected;

[0117] S300: Liquid is injected into the cell's reservoir using a liquid injection device;

[0118] S400: After the liquid injection is completed, the liquid injection component and the liquid storage chamber of the battery cell are disconnected.

[0119] For example, by evacuating the electrolyte storage chamber of the cell 600 before electrolyte injection, air and moisture in the storage chamber can be effectively removed, thereby improving the electrolyte injection efficiency and ensuring that the electrolyte can fully fill the storage chamber.

[0120] After the vacuuming is completed, ensure that the air extraction component 300 is disconnected from the liquid storage chamber of the battery cell 600 to effectively prevent outside air or impurities from entering the liquid storage chamber and improve the sealing performance of the liquid storage chamber of the battery cell 600.

[0121] Because the electrolyte is in a vacuum environment during the process of injecting electrolyte from the injection unit 200 into the storage chamber of the cell 600, the electrolyte can enter the cell 600 more quickly, shortening the injection time, improving production efficiency, and improving the uniform distribution of electrolyte in the storage chamber of the cell 600.

[0122] After vacuuming is completed, ensure that the liquid injection component 200 is disconnected from the liquid storage chamber of the battery cell 600. This can effectively prevent external air or impurities from entering the liquid storage chamber, while avoiding electrolyte leakage and ensuring the cleanliness of the liquid storage chamber of the battery cell 600.

[0123] Finally, the cell 600 is allowed to stand at a preset temperature. The electrolyte is then allowed to wet the storage chamber of the cell 600 by capillary action, ensuring that the electrolyte is fully wetted on the surface of the electrode material and improving the uniformity of electrolyte wetting in the cell 600.

[0124] The aforementioned cell liquid injection device and method can efficiently and conveniently complete the processes of vacuuming, injecting electrolyte, and wetting the cell 600. After each process is completed, the first docking end is closed to seal the cell 600's liquid storage chamber, ensuring that each process action is isolated from the external environment and guaranteeing process consistency. At the same time, the vacuuming and liquid injection processes of the aforementioned cell liquid injection device are performed in steps, which is beneficial to the balance of the production line cycle and greatly improves the efficiency of the cell 600 vacuuming, electrolyte injection, and electrolyte wetting processes. Compared with the prior art, it reduces the resistance of the electrolyte when wetting the cell 600's liquid storage chamber, improves the consistency of electrolyte wetting, and avoids problems such as black spots and lithium plating during cell 600 formation.

[0125] As one feasible implementation, a vacuum pump 300 is used to evacuate the liquid storage chamber of the battery cell 600; after the vacuum pump 300 is completed, the vacuum pump 300 and the liquid storage chamber of the battery cell 600 are disconnected; it also includes:

[0126] When the vacuum level of the liquid storage chamber of the battery cell 600 is less than the preset vacuum level, the vacuum pump 300 and the liquid storage chamber of the battery cell 600 are disconnected: the first docking end of the docking part 100 of the battery cell liquid injection device is closed.

[0127] The preset vacuum degree is P, and P satisfies: P≤300Pa.

[0128] For example, by setting a preset vacuum degree (P≤300Pa), when the vacuum degree inside the cell 600 is less than the preset vacuum degree, the first docking end is closed. In this way, before the cell electrolyte injection device injects electrolyte into the cell 600, the electrolyte storage chamber of the cell 600 is isolated from the outside, preventing air from entering the cell 600. This also prevents air from re-entering the cell 600 after the vacuuming is completed and before the electrolyte is injected, thus avoiding air affecting the consistency of electrolyte wetting after subsequent electrolyte injection.

[0129] As one feasible implementation, when the vacuum level of the liquid storage chamber of the battery cell 600 is less than a preset vacuum level, the vacuum pump 300 and the liquid storage chamber of the battery cell 600 are disconnected; the first docking end of the docking part 100 of the battery cell liquid injection device is closed. It also includes:

[0130] Within a preset time period, when the preset vacuum degree P satisfies: P≤300Pa, the liquid storage chamber of the pumping unit 300 and the battery cell 600 are disconnected; the first docking end and the second docking end of the docking unit 100 are disconnected.

[0131] By monitoring the vacuum level of the electrolyte reservoir in cell 600 within a preset time period, the system ensures that the reservoir reaches and is maintained at an ideal vacuum level. This precise control helps optimize electrolyte injection conditions.

[0132] Maintaining a stable vacuum level within a preset time ensures that each 600-cell battery is injected with electrolyte under the same vacuum conditions, improving the consistency and repeatability of the electrolyte injection process.

[0133] As one feasible implementation, when the vacuum level of the liquid storage chamber of the battery cell 600 is less than a preset vacuum level, the vacuum pump 300 and the liquid storage chamber of the battery cell 600 are disconnected; the first docking end of the docking part 100 of the battery cell liquid injection device is closed; it also includes:

[0134] Within a preset time period, when the change in vacuum degree of cell 600 is less than or equal to 1 Pa / s, the liquid injection port of cell 600 is closed.

[0135] By monitoring changes in the vacuum level within the electrolyte reservoir of cell 600, operation is ensured only when the vacuum level is reached and maintained at a stable state. This helps provide consistent electrolyte filling conditions and reduces bubble formation.

[0136] When the vacuum level of cell 600 changes to less than or equal to 1 Pa / s, the vacuum level change is considered to have stabilized. The electrolyte injection port is closed when the vacuum level change stabilizes to ensure that the electrolyte is injected into cell 600 under stable conditions, improving the uniformity and consistency of the electrolyte injection. By monitoring the rate of change in vacuum level, it is possible to more accurately determine when to close the electrolyte injection port, avoiding process instability caused by closing it too early or too late.

[0137] By promptly closing the injection port after the vacuum level stabilizes, the operating time and energy consumption of the vacuum pump 300 are reduced, thus lowering the equipment load.

[0138] As one feasible implementation method, the preset vacuum degree P satisfies: 30Pa≤P≤70Pa.

[0139] Conversely, when the preset vacuum level P < 30 Pa, the preset vacuum level is relatively low. An excessively low vacuum level (i.e., an excessively high vacuum level) can indeed affect the physical structure of the cell 600, especially when the cell 600 material is thin or the structure is complex. Extremely high vacuum may lead to uneven pressure inside the material, thereby increasing the risk of stress and deformation.

[0140] In addition, maintaining a lower vacuum level requires higher energy consumption and equipment load, which may lead to accelerated equipment wear and increased maintenance costs.

[0141] Therefore, the preset vacuum level P in this embodiment satisfies: 30Pa≤P≤70Pa. Within this vacuum range, air and bubbles inside the cell 600 can be effectively removed, ensuring that the electrolyte can fully wet the electrode material, thereby improving the performance and consistency of the cell 600. Moreover, this preset vacuum level will not damage the structure of the cell 600, avoiding excessive stress and deformation of the internal structure of the cell 600.

[0142] As one feasible implementation method, the preset time period is T, where T satisfies: T≥10s.

[0143] Conversely, when the preset time period T < 10s, the preset time period is relatively short. Within this short time period, the vacuum level of cell 600 may be unstable, affecting the electrolyte wetting effect and the performance of cell 600. A stable vacuum level may not be achieved or maintained within a short time, leading to uneven electrolyte injection.

[0144] Therefore, in this embodiment, the preset time period T ≥ 10s. This helps to ensure the stability of the vacuum in the electrolyte storage chamber of the battery cell 600, helps to ensure that air bubbles inside the battery cell 600 are fully removed, and improves the wetting effect of the electrolyte and the performance of the battery cell 600.

[0145] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0146] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A battery cell liquid injection device, characterized in that, include: A docking member (100) having a first docking member (110) and a second docking member (120), the second docking member (120) being used to communicate with the liquid storage chamber of the battery cell (600); Injection part (200), the injection part (200) is connected to the first docking part (110) of the docking part (100); An air extraction component (300) is connected to the first docking component (110) of the docking component (100); When the cell (600) liquid injection device is in a vacuum state, the vacuuming component (300) is connected to one end of the first docking component (110), and the other end of the first docking component (110) is connected to the second docking component (120), so that the vacuuming component (300) is connected to the liquid storage chamber of the cell (600), and the liquid injection component (200) is disconnected from the liquid storage chamber of the cell (600); When the cell liquid injection device is in the liquid injection state, the liquid injection component (200) is connected to one end of the first docking component (110), and the other end of the first docking component (110) is connected to the second docking component (120), so that the liquid injection component (200) is connected to the liquid storage chamber of the cell (600), and the air extraction component (300) is disconnected from the liquid storage chamber of the cell (600); When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the air extraction component (300) is disconnected from the liquid storage chamber of the cell (600); the liquid injection component (200) is disconnected from the liquid storage chamber of the cell (600).

2. The cell electrolyte injection device according to claim 1, characterized in that, The second docking component (120) is provided with a normally closed shut-off valve; When the cell liquid injection device is in a vacuum state, the normally closed shut-off valve is in an open state, the first docking part (110) and the second docking part (120) are connected, the air extraction part (300) is connected to the liquid storage chamber of the cell (600) through the first docking part (110) and the second docking part (120), and the liquid injection part (200) is disconnected from the liquid storage chamber of the cell (600); When the cell liquid injection device is in the liquid injection state, the normally closed shut-off valve is in the open state, the first docking part (110) and the second docking part (120) are connected, the liquid injection part (200) is connected to the liquid storage chamber of the cell (600) through the first docking part (110) and the second docking part (120), and the air extraction part (300) is disconnected from the liquid storage chamber of the cell (600); When the cell liquid injection device is in a non-liquid injection and non-vacuum state, the normally closed shut-off valve is in an open state, the first docking part (110) and the second docking part (120) are disconnected, the air extraction part (300) is disconnected from the liquid storage chamber of the cell (600), and the liquid injection part (200) is disconnected from the liquid storage chamber of the cell (600).

3. The cell electrolyte injection device according to claim 1, characterized in that, The docking component (100) includes a valve body and a valve core. The valve body has a first channel, a second channel and a third channel in its cavity. The first end of the first channel is connected to the liquid injection component (200), the first end of the second channel is connected to the air extraction component (300), and the first end of the third channel is used to communicate with the liquid storage cavity of the battery cell (600). The valve core is movably disposed in the cavity, and the valve core switches between a first position, a neutral position, and a second position; When the valve core is in the first position, the second end of the first channel is connected to the second end of the third channel, and the second end of the second channel is disconnected from the second end of the third channel, forming the liquid injection state of the cell liquid injection device; When the valve core is in the second position, the second end of the second channel is connected to the second end of the third channel, and the second end of the first channel is disconnected from the second end of the third channel, forming a vacuum state for the cell liquid injection device; When the valve core is in the neutral position, the second end of the second channel and the second end of the third channel are disconnected, and the second end of the first channel and the second end of the third channel are disconnected, forming a non-liquid injection and non-vacuum state of the cell liquid injection device.

4. The cell electrolyte injection device according to claim 2 or 3, characterized in that, The cell liquid injection device further includes a liquid injection needle (500), the first end of which is connected to the liquid storage chamber of the cell (600), and the second end of which is connected to the second docking member (120).

5. The cell electrolyte injection device according to claim 4, characterized in that, The cell liquid injection device further includes a base (400) having a support platform for placing the cell (600).

6. The cell electrolyte injection device according to claim 5, characterized in that, The base (400) further includes a clamping section (410) located on the support platform. The clamping end of the clamping section (410) forms a clamping area for clamping and fixing the battery cell (600).

7. The cell electrolyte injection device according to claim 4, characterized in that, The cell liquid injection device also includes a liquid injection pipeline (210), the first end of which is connected to the liquid injection component (200), the second end of which is connected to the docking component (100), and a liquid injection valve is provided on the liquid injection pipeline (210).

8. The cell electrolyte injection device according to claim 4, characterized in that, The battery cell liquid injection device also includes a vacuum pipe (310), the first end of which is connected to the vacuum component (300), the second end of which is connected to the docking component (100), and a vacuum valve is provided on the vacuum pipe (310).

9. A method for injecting electrolyte into a battery cell, characterized in that, The battery cell electrolyte filling device according to any one of claims 1-8, wherein the battery cell electrolyte filling method comprises: A vacuum is applied to the liquid storage chamber of the battery cell (600) using a vacuum pump (300); Once the vacuuming is complete, the vacuuming component (300) and the liquid storage chamber of the battery cell (600) are disconnected; Liquid is injected into the reservoir of the battery cell (600) using a liquid injection device (200); Once the liquid injection is complete, the liquid injection component (200) and the liquid storage chamber of the battery cell (600) are disconnected.

10. The cell electrolyte injection method according to claim 9, characterized in that, The method involves using a vacuum pump (300) to evacuate the liquid storage chamber of the battery cell (600); after the vacuuming is completed, the vacuum pump (300) and the liquid storage chamber of the battery cell (600) are disconnected; the method also includes: When the vacuum level of the liquid storage chamber of the battery cell (600) is less than the preset vacuum level, the vacuum pump (300) and the liquid storage chamber of the battery cell (600) are disconnected; the second docking part (120) of the docking part (100) of the battery cell liquid injection device is closed; The preset vacuum degree is P, and P satisfies: P≤300Pa.

11. The cell electrolyte injection method according to claim 10, characterized in that, When the vacuum level of the liquid storage chamber of the battery cell (600) is less than a preset vacuum level, the vacuum pump (300) and the liquid storage chamber of the battery cell (600) are disconnected; the second docking part (120) of the docking part (100) of the battery cell injection device is closed; it also includes: Within a preset time period, when the preset vacuum degree P satisfies: P≤300Pa, the liquid storage chamber of the pumping unit (300) and the battery cell (600) is disconnected; the second docking part (120) of the docking part (100) is closed.

12. The cell electrolyte injection method according to claim 11, characterized in that, When the vacuum level of the liquid storage chamber of the battery cell (600) is less than the preset vacuum level, the vacuum pump (300) and the liquid storage chamber of the battery cell (600) are disconnected. The second docking member (120) of the docking member (100) of the cell liquid injection device is closed; it also includes: During the preset time period, when the change in vacuum of the battery cell (600) is less than or equal to 1 Pa / s, the liquid injection port of the battery cell (600) is closed.

13. The cell electrolyte injection method according to claim 10, characterized in that, The preset vacuum degree P satisfies: 30Pa≤P≤70Pa.

14. The cell electrolyte injection method according to claim 11, characterized in that, The preset time period is T, and T satisfies: T≥10s.

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