Liquid injection mechanism and liquid injection apparatus

Abstract

The utility model relates to the technical field of battery discloses a kind of liquid injection mechanism and liquid injection equipment, and liquid injection mechanism has first direction, and liquid injection mechanism includes: liquid injection nozzle, with gas-liquid passage that is penetrated along first direction, gas-liquid passage is used to communicate with injection port;Liquid injection needle includes main part and needle body part, and needle body part is connected to one end of main part and extends along first direction;Liquid injection needle further includes mutually isolated air passage and liquid injection channel, air passage is penetrated main part, and liquid injection channel is simultaneously penetrated main part and needle body part, and needle body part is used to insert injection port to make liquid injection channel and injection port communicate;Wherein, liquid injection nozzle is connected to one end of main part along first direction, and needle body part is arranged in gas-liquid passage;Gap is between needle body part and gas-liquid passage wall part, and gap is used to make air passage and injection port communicate.The liquid injection mechanism and liquid injection equipment of the utility model reduce debugging difficulty, avoid vacuum pipeline crystallization, improve use stability and reduce maintenance difficulty.

Description

Technical Field

[0001] This utility model relates to the technical field of batteries, and in particular to a liquid injection mechanism and liquid injection equipment. Background Technology

[0002] During the manufacturing process of power batteries, when filling the battery and the accompanying liquid filling cup with liquid, it is necessary to vacuum the liquid filling cup.

[0003] Currently, there are two methods. Taking a 24PPM device with a 36-minute settling time as an example, a single machine requires 32 sets of injection cups, with 36 injection cups in each set, meaning that 1152 cells can be injected at a time. Method 1: The vacuum port and liquid injection port of the portable liquid injection cup are placed on the top cover. It is stable in use, but the number of holes in the liquid injection cup is large, generally 2304. The traditional liquid injection cup used before was that each liquid injection cup had a liquid outlet at the bottom that was connected to the corresponding battery cell, and two holes at the top, one for vacuuming and one for liquid injection. The upstream liquid storage mechanism and vacuuming mechanism were connected to the vacuuming port and the liquid injection port through two independent pipes. Therefore, there were many sealing points, which made the debugging more difficult. In recent years, an integrated liquid injection cup has been proposed. Each liquid injection cup has a liquid outlet at the bottom that is connected to the corresponding battery cell, but the liquid injection port and vacuuming port at the top are combined into one. The upstream liquid storage mechanism and vacuuming mechanism are first connected to the same three-way valve and then connected to the liquid injection cup through the same pipe. However, after repeated use, the electrolyte will be drawn back into the vacuum pipe, causing the three-way valve to crystallize and become blocked, affecting stability. Utility Model Content

[0004] The aim is to solve at least one of the technical problems existing in the prior art. This utility model provides a liquid injection mechanism and liquid injection equipment, which reduces the number of docking holes in the liquid injection cup, reduces the difficulty of debugging, avoids crystallization in vacuum pipelines, improves the stability of use, and reduces the difficulty of maintenance.

[0005] To achieve the above objectives, this utility model provides a liquid injection mechanism for sealing connection with a liquid injection cup, wherein the liquid injection cup is provided with a liquid injection port, the liquid injection mechanism has a first direction, and the liquid injection mechanism includes:

[0006] The injection nozzle has a gas-liquid channel extending along the first direction, the gas-liquid channel being used to communicate with the injection port;

[0007] The injection needle includes a main body and a needle body, the needle body being connected to one end of the main body along a first direction and extending along the first direction; the injection needle also includes a venting channel and an injection channel that are isolated from each other, the venting channel penetrating the main body, the injection channel penetrating both the main body and the needle body along the first direction, and the needle body being used to insert into the injection port so that the injection channel communicates with the injection port;

[0008] The injection nozzle is connected to one end of the main body along the first direction, and the needle body passes through the gas-liquid channel; there is a gap between the needle body and the wall of the gas-liquid channel, and the gap is used to connect the air passage and the injection port.

[0009] As a preferred embodiment, the injection mechanism further includes an end cap disposed within the gas-liquid channel; the end cap has a first end cap hole and a second end cap hole extending through the first direction, the first end cap hole and the second end cap hole being spaced apart from each other, the needle body portion passing through the second end cap hole, and the first end cap hole being located within the gap and connecting the venting channel and the injection port.

[0010] As a preferred embodiment, the first end cap hole is provided with a plurality of holes, and the plurality of first end cap holes are arranged at intervals around the second end cap hole.

[0011] As a preferred embodiment, along the first direction, one end of the needle body that is opposite to the main body protrudes from the injection nozzle.

[0012] As a preferred embodiment, along the first direction, the length of the end cap is less than the length of the injection nozzle.

[0013] As a preferred embodiment, the main body includes a first end face, a second end face, and a main body side face. The first end face and the second end face are disposed opposite to each other and are respectively connected to the two ends of the main body side face along the first direction. The needle body is connected to the second end face. The air passage has a first air passage opening and a second air passage opening. The first air passage opening is opened on the main body side face, and the second air passage opening is opened on the second end face and communicates with the gap.

[0014] As a preferred embodiment, the second end face has a connecting groove, the connecting groove having a connecting bottom surface perpendicular to the first direction and a connecting side surface parallel to the first direction; the second airway and the needle body are both disposed on the connecting bottom surface.

[0015] As a preferred embodiment, the connecting side is provided with a first connecting portion, and the end cap is provided with a second connecting portion near the end of the main body along the first direction, and the first connecting portion and the second connecting portion are connected to each other.

[0016] An electrolyte injection device for injecting electrolyte into a battery cell, comprising:

[0017] Pump-liquid assembly, used to connect to the electrolyte source;

[0018] Gas source assembly, used to connect to a vacuum source;

[0019] The liquid injection cup includes a cup body and a cup spout. The cup body has a receiving cavity. The cup spout is connected to one end of the cup body along the first direction. The liquid injection port is opened at one end of the cup body away from the cup spout. Both the cup spout and the liquid injection port are connected to the receiving cavity. The cup spout is used to connect to the battery cell.

[0020] The liquid injection mechanism includes a liquid injection channel connected to the pump assembly; a venting channel connected to the gas source assembly; a liquid injection nozzle connected to the cup body, and the projection of the liquid injection nozzle along the first direction is configured to at least surround the liquid injection port, so that the gas-liquid channel is in sealed communication with the liquid injection port.

[0021] As a preferred embodiment, the pump assembly includes a buffer cup, a dispensing pump, a first dispensing valve, and a second dispensing valve; one end of the dispensing pump is connected to the electrolyte source, and the other end is connected to the buffer cup via the first dispensing valve; the buffer cup is connected to the dispensing channel via the second dispensing valve; and / or,

[0022] The gas source assembly includes a pressure gauge, a vacuum valve, and a pipe for communicating with a vacuum source. The pipe is connected to the air passage through the vacuum valve, and the pressure gauge is connected to the pipe and used to detect the gas pressure inside the pipe.

[0023] Compared with the prior art, the liquid injection mechanism and equipment of this utility model have the following advantages: The liquid injection needle includes a main body and a needle body. The liquid injection needle is provided with a venting channel and a liquid injection channel that are isolated from each other. The liquid injection channel passes through the main body and the needle body respectively. The liquid injection nozzle is provided with a gas-liquid channel. The liquid injection nozzle is fixed to one end of the main body. The needle body extends out of the liquid injection nozzle through the gas-liquid channel to facilitate insertion into the liquid injection port to inject liquid into the battery cell. There is a gap between the needle body and the wall of the gas-liquid channel. The venting channel passes through the main body and communicates with the gas-liquid channel through the gap. One end of the venting channel is connected to a vacuum source, and the other end is connected to the liquid injection port through the gas-liquid channel to achieve vacuuming of the battery cell. Since the liquid injection channel and the venting channel are respectively connected to the liquid injection port through the gas-liquid channel, the liquid injection nozzle and the liquid injection port are sealed together, thereby reducing the number of connection points between the liquid injection cup and the liquid injection mechanism, reducing assembly and debugging costs, reducing the difficulty of early debugging, and reducing the workload of subsequent production and maintenance. Because the injection channel and the venting channel are isolated from each other, and the venting channel is connected to the injection port through the gas-liquid channel, the crystallization problem of the electrolyte when passing through the three-way valve is avoided, and the maintenance difficulty of subsequent use is reduced. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model.

[0025] Figure 2 This is a cross-sectional view of the overall structure of an embodiment of this utility model.

[0026] Figure 3 This is a schematic diagram of the injection needle structure according to an embodiment of the present invention.

[0027] Figure 4 This is a cross-sectional view of the injection needle according to an embodiment of the present invention.

[0028] Figure 5 This is a structural diagram of the disassembled components of the injection nozzle according to an embodiment of this utility model.

[0029] Figure 6 This is a schematic diagram of the liquid injection cup according to an embodiment of the present invention.

[0030] Figure 7 This is a schematic diagram of the connection structure of the liquid injection device according to an embodiment of the present invention.

[0031] In the picture:

[0032] X, first direction;

[0033] 1. Injection nozzle; 11. Gas-liquid channel; 12. Gap;

[0034] 2. Injection needle; 21. Ventilation channel; 211. First airway opening; 212. Second airway opening; 22. Injection channel; 221. Injection inlet; 222. Injection outlet; 23. Main body; 231. First end face; 232. Second end face; 2321. Connecting side; 23211. First connecting part; 2322. Connecting bottom surface; 2323. Connecting groove; 233. Main body side; 24. Needle body;

[0035] 3. Injection cup; 31. Cup body; 311. Injection port; 312. Receiving cavity; 32. Cup spout;

[0036] 4. Pump assembly; 41. Buffer cup; 42. Injection pump; 43. First injection valve; 44. Second injection valve;

[0037] 5. Gas supply components; 51. Pressure gauge; 52. Vacuum valve; 53. Pipe body;

[0038] 6. Battery cells;

[0039] 7. End cap; 71. Second connecting part; 72. First end cap hole; 73. Second end cap hole. Detailed Implementation

[0040] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0041] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, 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, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0042] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, 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 application according to the specific circumstances.

[0043] In this application, unless otherwise expressly 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 being 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 being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0044] In the embodiments of the application, "parallel" refers to a state in which the angle formed by two lines, a line and a surface, or a surface is -1° to 1°. "Perpendicular" refers to a state in which the angle formed by two lines, a line and a surface, or a surface is 89° to 91°. Equal distances, equal angles, or equal areas refer to a state in which the tolerance range is -1% to 1%.

[0045] like Figures 1 to 7As shown, a preferred embodiment of the present invention provides a liquid injection mechanism for sealing connection with a liquid injection cup 3. The liquid injection cup 3 is provided with a liquid injection port 311. The liquid injection mechanism has a first direction X and includes:

[0046] The injection nozzle 1 has a gas-liquid channel 11 extending along the first direction X, and the gas-liquid channel 11 is used to communicate with the injection port 311.

[0047] The injection needle 2 includes a main body 23 and a needle body 24. The needle body 24 is connected to one end of the main body 23 along the first direction X and extends along the first direction X. The injection needle 2 also includes a vent 21 and an injection channel 22 that are isolated from each other. The vent 21 passes through the main body 23, and the injection channel 22 passes through both the main body 23 and the needle body 24 along the first direction X. The needle body 24 is used to insert into the injection port 311 so that the injection channel 22 communicates with the injection port 311.

[0048] The injection nozzle 1 is connected to one end of the main body 23 along the first direction X, and the needle body 24 passes through the gas-liquid channel 11; there is a gap 12 between the needle body 24 and the wall of the gas-liquid channel 11, and the gap 12 is used to connect the air passage 21 and the injection port 311.

[0049] The liquid injection mechanism of this utility model includes a liquid injection needle 2 comprising a main body 23 and a needle body 24. The liquid injection needle 2 is provided with a venting channel 21 and a liquid injection channel 22 that are isolated from each other. The liquid injection channel 22 passes through both the main body 23 and the needle body 24. The liquid injection nozzle 1 is provided with a gas-liquid channel 11, the radius of which is smaller than that of the main body 23. The liquid injection nozzle 1 is fixed to one end of the main body 23. The needle body 24 extends out of the liquid injection nozzle 1 through the gas-liquid channel 11 to facilitate insertion into the liquid injection port 311 to inject liquid into the battery cell 6. A gap 12 exists between the needle body 24 and the wall of the gas-liquid channel 11. The venting channel 21 passes through the main body 23 and communicates with the gas-liquid channel 11 through the gap 12. One end of the venting channel 21 is connected to a vacuum source, and the other end is connected to the liquid injection port 311 through the gap 12 to achieve vacuuming of the battery cell 6. Since both the injection channel 22 and the vent 21 are confined within the area of ​​the gas-liquid channel 11 and connected to the injection port 311, the injection nozzle 1 and the injection port 311 are sealed together. This reduces the number of connection points between the injection cup 3 and the injection mechanism, lowers assembly and debugging costs, reduces initial debugging difficulty, and reduces subsequent production and maintenance workload. Because the injection channel 22 and the vent 21 are isolated from each other, and the vent 21 is connected to the injection port 311 through the gas-liquid channel 11, the crystallization problem of the electrolyte passing through the three-way valve is avoided, reducing the difficulty of subsequent maintenance.

[0050] The direction of the ventilation channel 21 can be adjusted according to actual needs. For example, the ventilation channel 21 can also extend along the first direction X, or the ventilation channel 21 can extend in a direction perpendicular to the first direction X, as long as the ventilation channel 21 and the injection channel 22 are spaced apart from each other.

[0051] Furthermore, the injection mechanism also includes an end cap 7 disposed within the gas-liquid channel 11. The end cap 7 is installed within the gas-liquid channel 11, wherein the end cap 7 has a first end cap hole 72 and a second end cap hole 73 extending along the first direction X. The first end cap hole 72 and the second end cap hole 73 are spaced apart from each other. The needle body 24 passes through the second end cap hole 73. The first end cap hole 72 is located within the gap 12 and connects the vent 21 and the injection port 311. After passing through the second end cap hole 73, the needle body 24 extends into the injection port 311, thereby injecting liquid into the injection cup 3 through the needle body 24. The vent 21 is connected to the injection port through the first end cap hole 72 to achieve vacuuming of the injection cup 3, thereby isolating the components of the injection and vacuuming steps from each other, avoiding the crystallization problem of sharing a three-way valve, and reducing the difficulty of subsequent maintenance.

[0052] In one embodiment, the shape and size of the second end cap hole 73 are respectively set to correspond to the shape of the outer peripheral surface of the needle body 24. The needle body 24 is positioned through the second end cap hole 73, thereby improving the accuracy of the assembly position of the needle body 24 and the end cap 7.

[0053] In one embodiment, both the end cap 7 and the needle body 24 are cylindrical. The end cap 7 and the needle body 24 are coaxially arranged. The second end cap hole 73 in the middle provides stable axial guidance for the injection needle 2 tube, ensuring that the needle tube remains vertically aligned during injection and preventing wear of the needle body 24 during assembly.

[0054] Furthermore, multiple first end cap holes 72 are provided, and these multiple first end cap holes 72 are spaced around the second end cap hole 73. The multiple first end cap holes 72 surrounding the second end cap hole 73 form a symmetrical negative pressure field, making the vacuum distribution inside the injection cup 3 more uniform. The spaced distribution of small holes can avoid stress concentration in the middle of the end cap 7, and maintain the mechanical strength of the end cap 7 while ensuring the negative pressure flow.

[0055] In one embodiment, 6-10 first end cap holes 72 are provided, and multiple first end cap holes 72 are equally spaced along the circumference of the end cap 7 to ensure negative pressure flow while maintaining the mechanical strength of the end cap 7.

[0056] Furthermore, along the first direction X, one end of the needle body 24, away from the main body 23, protrudes from the injection nozzle 1. The needle body 24 passes through the gas-liquid channel 11 and protrudes from the injection nozzle 1, so that the part of the needle body 24 protruding from the injection nozzle 1 can be directly inserted into the injection cup 3, ensuring that the electrolyte is directly injected into the bottom of the injection cup 3, rather than flowing along the inner wall of the injection nozzle 1, thus reducing the phenomenon of liquid adhering to the wall.

[0057] Furthermore, along the first direction X, the length of the end cap 7 is less than the length of the injection nozzle 1. After passing through the first end cap hole 72, the negative pressure gas will flow a certain distance within the gas-liquid channel 11 before entering the injection cup 3. The gas-liquid channel 11 between the first end cap hole 72 and the injection cup 3 forms a buffer chamber for the negative pressure gas, making the negative pressure distribution more uniform. At the same time, the end cap 7 is located within the gas-liquid channel 11, and the needle body 24 protrudes from the injection nozzle 1 towards the injection cup 3, so that there is a longer distance between the first end cap hole 72 and the injection end of the needle body 24, reducing the risk of electrolyte crystallization clogging the first end cap hole 72.

[0058] Furthermore, the main body 23 includes a first end face 231, a second end face 232, and a main body side face 233. The first end face 231 and the second end face 232 are arranged opposite to each other and are respectively connected to the two ends of the main body side face 233 along the first direction X. The needle body 24 is connected to the second end face 232. The ventilation channel 21 has a first airway 211 and a second airway 212. The first airway 211 is located on the main body side face 233, and the second airway 212 is located on the second end face 232 and communicates with the gap 12. The first airway 211 is located on the main body side face 233, and the second airway 212 is located on the second end face 232, forming an L-shaped airflow channel. This layout allows the negative pressure gas to enter from the side and be directly guided to the gap 12 between the needle body 24 and the injection cup 3, reducing airflow detours. The open arrangement of the second airway 212 and the second end face 232 facilitates direct rinsing or purging of residual electrolyte after disassembly, reducing downtime. The first air inlet 211 is located on the side 233 of the main body, which can meet the connection requirements of negative pressure pipelines at different angles and adapt to the space constraints of the equipment.

[0059] Furthermore, the second end face 232 has a connecting groove 2323, which has a connecting bottom surface 2322 perpendicular to the first direction X and a connecting side surface 2321 parallel to the first direction X. The second air passage 212 and the needle body 24 are both located on the connecting bottom surface 2322. The connecting bottom surface 2322 is perpendicular to the first direction X, providing axial support for the needle body 24 to prevent needle vibration caused by liquid backlash during injection, thereby improving injection accuracy. The connecting side surface 2321 is parallel to the first direction X, forming an "L-shaped" reinforcing structure with the main body 23 to improve overall bending stiffness, making it suitable for high-frequency injection operations.

[0060] Furthermore, the connecting side 2321 is provided with a first connecting portion 23211, and the end cap 7 is provided with a second connecting portion 71 near the end of the main body 23 along the first direction X. The first connecting portion 23211 and the second connecting portion 71 are connected to each other. The first connecting portion 23211 and the second connecting portion 71 are mechanically connected (such as by threads, snaps, or interference fit) to disperse the axial recoil force generated during the injection process from the needle body 24 to the end cap 7 and the main body 23, thereby reducing needle vibration and improving injection accuracy.

[0061] In one embodiment, the first connecting part 23211 and the second connecting part 71 are detachably connected, facilitating the assembly of the end cap 7 and the main body 23 and improving assembly efficiency. Simultaneously, it also facilitates deep cleaning of the interior of the connecting groove 2323, resolving the issue of high-viscosity electrolyte residue. Preferably, the end cap 7 and the main body 23 are connected by a threaded structure.

[0062] An electrolyte injection device for injecting electrolyte into a battery cell 6, comprising:

[0063] Pump assembly 4 is used to connect to the electrolyte source;

[0064] Gas source component 5, used to connect to a vacuum source;

[0065] The liquid filling cup 3 includes a cup body 31 and a cup spout 32. The cup body 31 has a receiving cavity 312. The cup spout 32 is connected to one end of the cup body 31 along the first direction X. The liquid filling port 311 is opened at the end of the cup body 31 away from the cup spout 32. Both the cup spout 32 and the liquid filling port 311 are connected to the receiving cavity 312. The cup spout 32 is used to connect to the battery cell 6.

[0066] The liquid injection mechanism has a liquid injection channel 22 connected to the pump liquid assembly 4; a vent 21 connected to the gas source assembly 5; a liquid injection nozzle 1 connected to the cup body 31, and the projection of the liquid injection nozzle 1 along the first direction X is configured to at least surround the liquid injection port 311, so that the gas-liquid channel 11 and the liquid injection port 311 are sealed and connected.

[0067] The pump assembly 4 is used to communicate with the electrolyte. When the pump assembly 4 is started, it can inject electrolyte into the injection channel 22 and insert it into the receiving cavity 312 of the cup body 31 through the injection port 311 via the needle part 24 of the injection nozzle 1 to inject electrolyte into the injection cup 3. The gas source assembly 5 is used to communicate with the vacuum source. The gas source assembly 5 is connected to the vent 21, which is sealed to the injection port 311 via the injection nozzle 1. When the gas source assembly 5 is started, it can extract the air in the cup body 31 through the vent 21 to speed up the filling of liquid and improve the electrolyte injection efficiency.

[0068] Furthermore, the pump assembly 4 includes a buffer cup 41, a dispensing pump 42, a first dispensing valve 43, and a second dispensing valve 44. One end of the dispensing pump 42 is connected to an electrolyte source, and the other end is connected to the buffer cup 41 via the first dispensing valve 43. The buffer cup 41 is connected to the dispensing channel 22 via the second dispensing valve 44. The dispensing pump 42 is used to pump the electrolyte source into the buffer cup 41. The dispensing pump 42 is connected to the buffer cup 41 via the first dispensing valve 43, and the first dispensing valve 43 controls the opening and closing of the passage between the dispensing pump 42 and the buffer cup 41. The buffer cup 41 is used to temporarily store the electrolyte. The buffer cup 41 is connected to the dispensing channel 22 via the second dispensing valve 44, and the second dispensing valve 44 controls the opening and closing of the passage between the buffer cup 41 and the dispensing channel 22.

[0069] And / or, the gas source assembly 5 includes a pressure gauge 51, a vacuum valve 52, and a pipe 53 for communicating with a vacuum source. The pipe 53 is connected to the ventilation channel 21 through the vacuum valve 52. The vacuum valve 52 is used to control the opening and closing of the passage between the ventilation channel 21 and the pipe 53. The pressure gauge 51 is connected to the pipe 53 and is used to detect the gas pressure inside the pipe 53.

[0070] The usage process of this utility model:

[0071] The second injection valve 44 is closed and the first injection valve 43 is opened. The electrolyte is pumped into the buffer cup 41 by the injection pump 42 and the electrolyte is temporarily stored in the buffer cup 41.

[0072] Insert the needle body 24 of the injection needle 2 into the injection port 311, and seal the gas-liquid channel 11 of the injection nozzle 1 with the injection port 311.

[0073] Open the vacuum valve 52, and all the air in the liquid injection cup 3 and the liquid injection product (i.e., battery) is extracted through the air source component 5. The pressure in the tube 53 is monitored by the pressure gauge 51. When the pressure reaches the set value, close the vacuum valve 52 to keep the liquid injection cup 3 and the liquid injection product in the set vacuum state.

[0074] Open the second injection valve 44 so that the electrolyte in the buffer cup 41 is drawn into the injection cup 3 and the product due to the vacuum, thereby completing the injection of electrode liquid into the battery.

[0075] In summary, this utility model embodiment provides a liquid injection mechanism and liquid injection device. The liquid injection needle 2 includes a main body 23 and a needle body 24. The liquid injection needle 2 is provided with a mutually isolated venting channel 21 and a liquid injection channel 22. The liquid injection channel 22 passes through the main body 23 and the needle body 24 respectively. The liquid injection nozzle 1 is provided with a gas-liquid channel 11. The liquid injection nozzle 1 is fixedly connected to one end of the main body 23. The needle body 24 extends out of the liquid injection nozzle 1 through the gas-liquid channel 11 to facilitate insertion into the liquid injection port 311 to inject liquid into the battery cell 6. There is a gap 12 between the needle body 24 and the wall of the gas-liquid channel 11. The venting channel 21 passes through the main body 23 and communicates with the gas-liquid channel 11 through the gap 12. One end of the venting channel 21 is connected to a vacuum source, and the other end is connected to the liquid injection port 311 through the gas-liquid channel 11 to achieve vacuuming of the battery cell 6. Since the injection channel 22 and the vent 21 are respectively connected to the injection port 311 through the gas-liquid channel 11, and the injection nozzle 1 and the injection port 311 are sealed together, the number of connection points between the injection cup 3 and the injection mechanism is reduced, thereby lowering assembly and debugging costs, reducing the difficulty of initial debugging, and reducing the workload of subsequent production and maintenance. Because the injection channel 22 and the vent 21 are isolated from each other, and the vent 21 is connected to the injection port 311 through the gas-liquid channel 11, the crystallization problem of the electrolyte when passing through the three-way valve is avoided, reducing the difficulty of subsequent maintenance.

[0076] The above are merely preferred embodiments of this utility model. It should be noted that, for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of this utility model, and these improvements and substitutions should also be considered within the protection scope of this utility model.

Claims

1. A liquid injection mechanism for sealing connection with a liquid injection cup (3), wherein the liquid injection cup (3) is provided with a liquid injection port (311), characterized in that: The injection mechanism has a first direction (X), and the injection mechanism includes: The injection nozzle (1) has a gas-liquid channel (11) extending along the first direction (X), the gas-liquid channel (11) being used to communicate with the injection port (311); The injection needle (2) includes a main body (23) and a needle body (24). The needle body (24) is connected to one end of the main body (23) along the first direction (X) and extends along the first direction (X). The injection needle (2) also includes a venting channel (21) and an injection channel (22) that are isolated from each other. The venting channel (21) penetrates the main body (23). The injection channel (22) penetrates both the main body (23) and the needle body (24) along the first direction (X). The needle body (24) is used to insert into the injection port (311) so that the injection channel (22) communicates with the injection port (311). The injection nozzle (1) is connected to one end of the main body (23) along the first direction (X), and the needle body (24) passes through the gas-liquid channel (11); there is a gap (12) between the needle body (24) and the wall of the gas-liquid channel (11), and the gap (12) is used to connect the air passage (21) with the injection port (311).

2. The liquid injection mechanism according to claim 1, characterized in that: The liquid injection mechanism also includes an end cap (7) disposed in the gas-liquid channel (11); the end cap (7) is provided with a first end cap hole (72) and a second end cap hole (73) extending along the first direction (X), the first end cap hole (72) and the second end cap hole (73) are spaced apart from each other, the needle body (24) passes through the second end cap hole (73), the first end cap hole (72) is located in the gap (12) and connects the air passage (21) and the liquid injection port (311).

3. The liquid injection mechanism according to claim 2, characterized in that: The first end cap hole (72) is provided in multiple ways, and the multiple first end cap holes (72) are arranged at intervals around the second end cap hole (73).

4. The liquid injection mechanism according to claim 3, characterized in that: Along the first direction (X), one end of the needle body (24) opposite to the main body (23) protrudes from the injection nozzle (1).

5. The liquid injection mechanism according to claim 2, characterized in that: Along the first direction (X), the length of the end cap (7) is less than the length of the injection nozzle (1).

6. The liquid injection mechanism according to claim 2, characterized in that: The main body (23) includes a first end face (231), a second end face (232), and a main body side face (233). The first end face (231) and the second end face (232) are arranged opposite to each other and are respectively connected to the two ends of the main body side face (233) along the first direction (X). The needle body (24) is connected to the second end face (232). The air passage (21) is provided with a first air passage opening (211) and a second air passage opening (212). The first air passage opening (211) is opened on the main body side face (233), and the second air passage opening (212) is opened on the second end face (232) and communicates with the gap (12).

7. The liquid injection mechanism according to claim 6, characterized in that: The second end face (232) has a connecting groove (2323), the connecting groove (2323) has a connecting bottom surface (2322) perpendicular to the first direction (X) and a connecting side surface (2321) parallel to the first direction (X); the second airway (212) and the needle body (24) are both disposed on the connecting bottom surface (2322).

8. The liquid injection mechanism according to claim 7, characterized in that: The connecting side (2321) is provided with a first connecting part (23211), and the end cap (7) is provided with a second connecting part (71) near the end of the main body (23) along the first direction (X). The first connecting part (23211) and the second connecting part (71) are connected to each other.

9. A liquid injection device for injecting electrolyte into a battery cell, characterized in that: include: Pump-liquid assembly (4) is used to connect to the electrolyte source; Gas source assembly (5), used to connect to a vacuum source; The liquid injection cup (3) includes a cup body (31) and a spout (32). The cup body (31) has a receiving cavity (312). The spout (32) is connected to one end of the cup body (31) along the first direction (X). The liquid injection port (311) is opened at one end of the cup body (31) away from the spout (32). Both the spout (32) and the liquid injection port (311) are connected to the receiving cavity (312). The spout (32) is used to connect to the battery cell. And the liquid injection mechanism according to any one of claims 1-8; wherein the liquid injection channel (22) is connected to the pump liquid assembly (4); the vent (21) is connected to the gas source assembly (5); the liquid injection nozzle (1) is connected to the cup body (31), and the projection of the liquid injection nozzle (1) along the first direction (X) is configured to at least surround the liquid injection port (311) so that the gas-liquid channel (11) is in sealed communication with the liquid injection port (311).

10. The liquid injection device according to claim 9, characterized in that: The pump assembly (4) includes a buffer cup (41), a dispensing pump (42), a first dispensing valve (43), and a second dispensing valve (44); one end of the dispensing pump (42) is connected to the electrolyte source, and the other end is connected to the buffer cup (41) through the first dispensing valve (43); the buffer cup (41) is connected to the dispensing channel (22) through the second dispensing valve (44); and / or, The gas source assembly (5) includes a pressure gauge (51), a vacuum valve (52), and a pipe (53) for communicating with a vacuum source. The pipe (53) is connected to the air passage (21) through the vacuum valve (52). The pressure gauge (51) is connected to the pipe (53) and is used to detect the gas pressure inside the pipe (53).

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