Liquid injection device, liquid injection equipment and battery cell production line

Abstract

The utility model belongs to vehicle technical field especially relates to liquid injection device, liquid injection equipment and electric core production line. Liquid injection device includes liquid injection piece, first liquid injection system and second liquid injection system, and liquid injection piece is provided with first liquid inlet, second liquid inlet and liquid outlet, first liquid injection system communicates with first liquid inlet for injecting primary electrolyte to liquid injection piece, second liquid injection system communicates with second liquid inlet for injecting secondary electrolyte to liquid injection piece. When liquid injection device carries out secondary injection to electric core, liquid outlet is docked with the injection hole of electric core, then second liquid injection system injects the preset amount of secondary electrolyte into liquid injection piece, and first liquid injection system injects the loss amount of primary electrolyte in the process of negative pressure into liquid injection piece, and liquid injection piece injects primary electrolyte and secondary electrolyte into electric core, realizes the simultaneous injection of primary electrolyte and secondary electrolyte, guarantees the period of secondary injection, and avoids the increase of equipment investment and floor area.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a liquid injection device, liquid injection equipment and cell production line. Background Technology

[0002] A lithium-ion battery is a rechargeable battery that primarily functions by the movement of lithium ions between the positive and negative electrodes. During charging, lithium ions are extracted from the positive electrode, pass through the electrolyte, and embed into the negative electrode, leaving the negative electrode in a lithium-rich state. During discharging, the movement of lithium ions occurs in the reverse order of charging. The electrolyte, acting as the carrier of ion transport within the lithium-ion battery, plays a crucial role in its overall performance. The electrolyte serves as a bridge connecting the positive and negative electrodes, facilitating ion transport and current conduction within the battery.

[0003] With increasing performance requirements for cell storage and direct current resistance (DCR), a different electrolyte than the primary electrolyte needs to be used for secondary electrolyte filling. Considering the influence of solid electrolyte interphase (SEI) formation, the secondary electrolyte needs to be added after negative pressure formation. However, during negative pressure formation, gas is generated inside the cell and is expelled, resulting in the loss of primary electrolyte along with the gas. Therefore, the loss needs to be replenished after negative pressure formation. If the amount of electrolyte loss during negative pressure formation is estimated in advance and the primary electrolyte filling volume is increased, the following problems will arise: the inherent differences in gas generation per cell will lead to inconsistent electrolyte loss per cell, making the estimated amount impossible to quantify; increasing the primary electrolyte filling volume will increase the primary electrolyte filling time, affecting the efficiency of the primary electrolyte filling itself. Therefore, a secondary electrolyte injection process is needed to replenish the electrolyte. However, traditional secondary electrolyte injection devices are single-pipeline systems that can only inject one type of electrolyte. They cannot simultaneously address the issues of replenishing the electrolyte lost in the primary process and injecting the secondary electrolyte. If a scheme is adopted that first replenishes the electrolyte lost in the primary process and then injects the secondary electrolyte, it will increase the number of processes and the processing cycle. It will also require the addition of a logistics and transfer system, which will increase equipment costs and floor space. Utility Model Content

[0004] The purpose of this utility model is to provide a liquid injection device, liquid injection equipment and battery cell production line, which not only ensures the cycle of secondary liquid injection, but also avoids the increase in equipment investment and floor space.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] The liquid injection device includes:

[0007] The liquid injection component is provided with a first liquid inlet, a second liquid inlet, and a liquid outlet, wherein the liquid outlet is used to connect with the liquid injection hole of the battery cell.

[0008] The first liquid injection system is connected to the first liquid inlet and is used to inject electrolyte into the liquid injection component.

[0009] The second liquid injection system is connected to the second liquid inlet and is used to inject secondary electrolyte into the liquid injection component.

[0010] As a preferred technical solution for the liquid injection device, the first liquid injection system includes a first liquid storage component and a first liquid injection pump. The first liquid storage component stores primary electrolyte, the inlet of the first liquid injection pump is connected to the first liquid storage component, and the outlet of the first liquid injection pump is connected to the first liquid inlet.

[0011] As a preferred technical solution for the injection device, the first injection pump is a variable pump.

[0012] As a preferred technical solution for the liquid injection device, the first liquid injection system further includes a first liquid level detection element for detecting the liquid level in the first liquid storage device.

[0013] As a preferred technical solution for the liquid injection device, the second liquid injection system includes a second liquid storage component and a second liquid injection pump. The second liquid storage component stores secondary electrolyte, the inlet of the second liquid injection pump is connected to the second liquid storage component, and the outlet of the second liquid injection pump is connected to the second liquid inlet.

[0014] As a preferred technical solution for the injection device, the second injection pump is a metering pump.

[0015] As a preferred technical solution for the liquid injection device, the second liquid injection system further includes a second liquid level detection element for detecting the liquid level in the second liquid storage device.

[0016] As a preferred technical solution for the liquid injection device, a sealing component is also included, which can block the liquid outlet.

[0017] Liquid injection equipment, including the liquid injection device as described in any of the above embodiments.

[0018] The battery cell production line includes the liquid injection equipment described above.

[0019] The beneficial effects of this utility model are:

[0020] This invention provides a liquid injection device, including a liquid injection component, a first liquid injection system, and a second liquid injection system. The liquid injection component is provided with a first liquid inlet, a second liquid inlet, and a liquid outlet. The first liquid injection system is connected to the first liquid inlet and is used to inject primary electrolyte into the liquid injection component. The second liquid injection system is connected to the second liquid inlet and is used to inject secondary electrolyte into the liquid injection component. When using this liquid injection device to perform secondary liquid injection on a battery cell, the liquid outlet of the liquid injection component is connected to the liquid injection hole of the battery cell. Then, the second liquid injection system injects a preset amount of secondary electrolyte into the liquid injection component. At the same time, the first liquid injection system injects the amount of primary electrolyte lost during the negative pressure formation process into the liquid injection component. The liquid injection component injects both primary and secondary electrolytes into the battery cell together, realizing the simultaneous addition of primary and secondary electrolytes. This ensures the cycle of secondary liquid injection and avoids increasing equipment investment and floor space. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the liquid injection device provided in this embodiment of the utility model.

[0022] In the picture:

[0023] 10. Injection component; 11. First inlet; 12. Second inlet; 13. Vent; 20. First injection system; 21. First reservoir; 22. First injection pump; 23. First suction line; 24. First injection line; 30. Second injection system; 31. Second reservoir; 32. Second injection pump; 33. Second suction line; 34. Second injection line; 40. Sealing component;

[0024] 100. Battery cells. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0026] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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 or an electrical connection; 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. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0029] like Figure 1 As shown, this utility model embodiment provides a liquid injection device, including a liquid injection component 10, a first liquid injection system 20, and a second liquid injection system 30. The liquid injection component 10 is provided with at least a first liquid inlet 11, a second liquid inlet 12, and a liquid outlet. The liquid outlet is used to connect with the liquid injection hole of the battery cell. The first liquid injection system 20 is connected to the first liquid inlet 11 and is used to inject primary electrolyte into the liquid injection component 10. The second liquid injection system 30 is connected to the second liquid inlet 12 and is used to inject secondary electrolyte into the liquid injection component 10. When using this injection device to perform secondary electrolyte injection on the battery cell 100, the outlet of the injection component 10 is connected to the injection hole of the battery cell 100. Then, the second injection system 30 injects a preset amount of secondary electrolyte into the injection component 10. Simultaneously, the first injection system 20 injects the amount of primary electrolyte lost during the negative pressure formation process into the injection component 10. The injection component 10 injects both the primary and secondary electrolytes into the battery cell 10, achieving simultaneous injection of primary and secondary electrolytes. This ensures the cycle of secondary electrolyte injection and avoids increasing equipment investment and floor space. In this embodiment, the primary and secondary electrolytes are different liquids. In other embodiments, the primary and secondary electrolytes may be the same liquid.

[0030] In this embodiment, the liquid injection device further includes a sealing element 40, which can block the liquid outlet. When the first liquid injection system 20 and / or the second liquid injection system 30 inject liquid into the liquid injection component 10, the sealing element 40 blocks the liquid outlet. When the first liquid injection system 20 and / or the second liquid injection system 30 completes the liquid injection into the liquid injection component 10, the sealing element 40 is removed from the liquid outlet, the liquid outlet opens, and the electrolyte in the liquid injection component 10 is injected into the battery cell through the liquid outlet. Optionally, the sealing element 40 can be a sealing rod, a sealing plug, or a sealing valve; the form is not limited, as long as it can realize the opening and closing of the liquid outlet.

[0031] In this embodiment, the liquid injection component 10 is also provided with a vent 13, which is used to connect the inner and outer spaces of the liquid injection component 10. By providing the vent 13, gas can be introduced into the liquid injection component 10 for pressurization, or the liquid injection component 10 can be evacuated to facilitate the flow of electrolyte into the battery cell.

[0032] In this embodiment, the first injection system 20 includes a first liquid storage unit 21 and a first injection pump 22. The first liquid storage unit 21 is used to store primary electrolyte. The inlet of the first injection pump 22 is connected to the first liquid storage unit 21, and the outlet of the first injection pump 22 is connected to the first inlet 11. The first injection pump 22 can draw primary electrolyte from the first liquid storage unit 21 through the first suction pipe 23 and inject the primary electrolyte into the injection unit 10 through the first injection pipe 24. Optionally, the inlet of the first injection pump 22 is connected to the first liquid storage unit 21 through the first suction pipe 23, and / or the outlet of the first injection pump 22 is connected to the first inlet 11 through the first injection pipe 24.

[0033] In this embodiment, the first injection pump 22 is a variable displacement pump, such as an axial piston pump. The displacement of the variable displacement pump is adjustable, thereby adjusting the injection volume into the injection unit 10 according to the amount of primary electrolyte lost during the negative pressure formation process. The amount of primary electrolyte injected during the first injection is set as m1, the amount of primary electrolyte lost during the negative pressure formation process is set as m', and the amount of primary electrolyte drawn by the first injection pump 22 is m”. When m' is less than or equal to the set value (generally 1% * m1), no replenishment of primary electrolyte is required during the second injection, i.e., m” = 0; when m' is greater than the set value, the replenishment amount of primary electrolyte during the second injection is m” = m'. In other embodiments, the first injection pump 22 can also be a non-variable displacement pump. A flow meter can be installed on the first suction line 23 or the first injection line 24 to detect the injection volume of the first injection pump 22 and control the stopping of the first injection pump 22 based on the detection result.

[0034] In this embodiment, the first liquid injection system 20 further includes a first liquid level detection element for detecting the liquid level in the first liquid storage container 21. By setting the first liquid level detection element, the liquid level in the first liquid storage container 21 can be monitored, and the first liquid storage container 21 can be replenished in a timely manner. Optionally, the first liquid level detection element can be a float-type liquid level gauge or an optical liquid level gauge, etc.

[0035] In this embodiment, the first liquid injection system 20 further includes a first one-way valve. The first one-way valve is disposed on the first suction line 23 between the inlet of the first liquid injection pump 22 and the first liquid storage component 21 and / or on the first liquid injection line 24 between the outlet of the first liquid injection pump 22 and the first liquid inlet 11. The first one-way valve is configured to conduct in one direction from the first liquid storage component 21 to the first liquid inlet 11 to prevent the primary electrolyte from flowing back.

[0036] In this embodiment, the first liquid injection system 20 further includes a first filter element, which is disposed on the first liquid suction line 23 between the inlet of the first liquid injection pump 22 and the first liquid storage device 21 and / or on the first liquid injection line 24 between the outlet of the first liquid injection pump 22 and the first liquid inlet 11, so as to filter the primary electrolyte entering the liquid injection device 10.

[0037] In this embodiment, the second injection system 30 includes a second liquid storage unit 31 and a second injection pump 32. The second liquid storage unit 31 is used to store secondary electrolyte. The inlet of the second injection pump 32 is connected to the second liquid storage unit 31, and the outlet of the second injection pump 32 is connected to the second inlet 12. The second injection pump 32 can draw secondary electrolyte from the second liquid storage unit 31 through the second suction pipe 33 and inject the secondary electrolyte into the injection unit 10 through the second injection pipe 34. Optionally, the inlet of the second injection pump 32 is connected to the second liquid storage unit 31 through the second suction pipe 33, and / or the outlet of the second injection pump 32 is connected to the second inlet 12 through the second injection pipe 34.

[0038] In this embodiment, the second injection pump 32 is a metering pump, such as a gear pump or a vane pump. The metering pump has a fixed displacement, thereby enabling the injection of a metered amount of secondary electrolyte into the injection unit 10. In other embodiments, the second injection pump 32 can also be a non-metering pump. A flow meter can be installed on the second suction line 33 or the second injection line 34 to detect the injection volume of the second injection pump 32, and the pump can be stopped based on the detection result.

[0039] In this embodiment, the second liquid injection system 30 further includes a second liquid level detection element for detecting the liquid level in the second liquid storage container 31. By providing the second liquid level detection element, the liquid level in the second liquid storage container 31 can be monitored, allowing for timely replenishment of the second liquid storage container 31. Optionally, the second liquid level detection element can be a float-type liquid level gauge or an optical liquid level gauge, etc.

[0040] In this embodiment, the second liquid injection system 30 further includes a second one-way valve. The second one-way valve is disposed on the second suction line 33 between the inlet of the second liquid injection pump 32 and the second liquid storage device 31 and / or on the second liquid injection line 34 between the outlet of the second liquid injection pump 32 and the second liquid inlet 12. The second one-way valve is configured to conduct in one direction from the second liquid storage device 31 to the second liquid inlet 12 to prevent the secondary electrolyte from flowing back.

[0041] In this embodiment, the second liquid injection system 30 further includes a second filter element, which is disposed on the second liquid suction line 33 between the inlet of the second liquid injection pump 32 and the second liquid storage 31 and / or on the second liquid injection line 34 between the outlet of the second liquid injection pump 32 and the second liquid inlet 12, so as to filter the secondary electrolyte entering the liquid injection 10.

[0042] In this embodiment, by using a combination of variable pump and metering pump, while achieving metered injection of secondary electrolyte, the amount of primary electrolyte lost can be dynamically and differentially replenished. The replenishment can be differentiated and precise according to the amount of electrolyte lost during negative pressure formation of different cells 100, ensuring the consistency of the amount of primary electrolyte injected into each cell 100.

[0043] In other embodiments, the first injection system 20 and the second injection system 30 may also employ a vacuum negative pressure injection method to inject electrolyte into the injection component 10. For example, the first injection system 20 and the second injection system 30 may include a storage container and a vacuum suction device. The storage container is used to store electrolyte, and the vacuum suction device is used to evacuate the injection component 10 and / or the battery cell 100. The electrolyte in the storage container will be drawn into the injection component 10 under vacuum pressure. Alternatively, the first injection system 20 and the second injection system 30 may also employ a pressure tank pressurized injection method to inject electrolyte into the injection component 10. For example, the first injection system 20 and the second injection system 30 may include a pressure tank, which stores electrolyte. By filling the pressure tank with an inert gas (such as argon), the electrolyte is pushed through and quantitatively injected into the injection component 10.

[0044] This utility model embodiment also provides a liquid injection device, including a primary liquid injection device, a formation device, and the aforementioned liquid injection device. The primary liquid injection device is used to perform a primary liquid injection on the battery cell, the formation device is used to perform negative pressure formation on the battery cell, and the aforementioned liquid injection device is used to perform a secondary liquid injection on the battery cell. By using the aforementioned liquid injection device, the liquid injection cycle is guaranteed, while avoiding an increase in equipment investment and floor space.

[0045] This utility model embodiment also provides a battery cell production line, including the above-mentioned liquid injection equipment.

[0046] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A liquid injection device, characterized in that, include: The liquid injection component (10) is provided with a first liquid inlet (11), a second liquid inlet (12) and a liquid outlet, wherein the liquid outlet is used to connect with the liquid injection hole of the battery cell; The first liquid injection system (20) is connected to the first liquid inlet (11) and is used to inject electrolyte into the liquid injection component (10) once; The second liquid injection system (30) is connected to the second liquid inlet (12) and is used to inject secondary electrolyte into the liquid injection component (10).

2. The liquid injection device according to claim 1, characterized in that, The first liquid injection system (20) includes a first liquid storage device (21) and a first liquid injection pump (22). The first liquid storage device (21) stores primary electrolyte. The inlet of the first liquid injection pump (22) is connected to the first liquid storage device (21), and the outlet of the first liquid injection pump (22) is connected to the first liquid inlet (11).

3. The liquid injection device according to claim 2, characterized in that, The first injection pump (22) is a variable pump.

4. The liquid injection device according to claim 2, characterized in that, The first liquid injection system (20) also includes a first liquid level detection element for detecting the liquid level in the first liquid storage element (21).

5. The liquid injection device according to claim 1, characterized in that, The second liquid injection system (30) includes a second liquid storage device (31) and a second liquid injection pump (32). The second liquid storage device (31) stores secondary electrolyte. The inlet of the second liquid injection pump (32) is connected to the second liquid storage device (31), and the outlet of the second liquid injection pump (32) is connected to the second liquid inlet (12).

6. The liquid injection device according to claim 5, characterized in that, The second injection pump (32) is a metering pump.

7. The liquid injection device according to claim 5, characterized in that, The second liquid injection system (30) also includes a second liquid level detection element for detecting the liquid level in the second liquid storage element (31).

8. The liquid injection device according to any one of claims 1-7, characterized in that, The liquid injection device also includes a sealing element (40) that can block the liquid outlet.

9. A liquid injection device, characterized in that, Includes the liquid injection device as described in any one of claims 1-8.

10. A battery cell production line, characterized in that, Includes the liquid injection device as described in claim 9.

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