Auxiliary liquid injection device

Abstract

The utility model relates to the field of battery production, and discloses an auxiliary liquid injection device, which comprises a material tray, a liquid injection device, a liquid injection device and a liquid injection device, and is characterized in that the material tray is used for arranging battery cells to be injected; the base assembly is used for limiting and fixing the charging tray; each liquid storage jig comprises a positioning pressing plate and a plurality of liquid storage cup sleeves, a plurality of liquid injection through holes are formed in the positioning pressing plate, the liquid storage cup sleeves are arranged on the face, close to the material disc, of the positioning pressing plate, and the liquid storage cup sleeves are connected and communicated with the liquid injection through holes in a one-to-one correspondence mode; when the liquid storage jig is used, the plurality of liquid storage jigs are placed above the charging tray, and each liquid storage cup sleeve is matched and communicated with the battery cell to be filled with liquid, so that a liquid storage space is formed above the battery cell to be filled with liquid.

Description

Technical Field

[0001] The utility model relates to the field of battery production, in particular to an auxiliary liquid injection device. Background Art

[0002] In the process of manufacturing existing fully sealed batteries, the liquid injection process faces a series of challenges. The current liquid injection methods mainly include two types: the method of injecting a small amount of liquid in several times, that is, by repeating the liquid injection operation multiple times to accumulate the required volume of electrolyte; the other is to adopt the method of soaking the battery core directly in the electrolyte for liquid injection treatment. However, both of these methods have significant technical problems, which restrict the production efficiency and product quality.

[0003] First of all, the method of injecting liquid in multiple times seriously affects the liquid injection efficiency. Especially for some types of batteries, up to 10 or more liquid injection cycles may be required, which not only greatly reduces the overall production efficiency, but also increases the manufacturing cost and time consumption due to frequent operations. Secondly, the direct contact of the battery core during the liquid injection process is likely to cause electrolyte pollution, which not only affects the battery performance, but also causes a large amount of waste of precious raw materials. Moreover, although the soaking liquid injection method seems direct, it has been criticized for its interference with the subsequent sealing and welding steps. Specifically, the presence of the electrolyte is likely to have a negative impact on the sealing and welding quality of the steel shell, resulting in a significant increase in the welding defect rate. In severe cases, it even directly affects the airtightness and safety of the battery.

[0004] A deeper technical bottleneck lies in that although the tight-fitting design of the battery core enhances the sealing performance, it restricts the effective distribution and absorption of the electrolyte. Excessive liquid injection volume will cause electrolyte leakage, pollute the steel shell, and affect the battery stability; reducing the liquid injection volume requires multiple operations, prolongs the process, increases the risk of the winding core absorbing water, and excessive absorption of the electrolyte may lead to welding defects, or even battery explosion, loss of sealing performance, and product scrapping.

[0005] To sum up, the existing liquid injection technology for fully sealed batteries has problems such as low liquid injection efficiency, large waste of electrolyte, and high sealing and welding defect rate. Therefore, it is necessary to develop a new liquid injection technology to solve the above problems and improve the manufacturing efficiency and product quality of fully sealed batteries. Summary of the Invention

[0006] The purpose of the utility model is to overcome the deficiencies in the prior art and provide an auxiliary liquid injection device.

[0007] The purpose of the utility model is achieved by the following technical solutions:

[0008] An auxiliary liquid injection device includes:

[0009] A material tray for arranging and placing the battery cores to be injected with liquid;

[0010] A base assembly for limiting and fixing the tray.

[0011] A number of liquid storage fixtures, each of which includes a positioning pressing plate and a number of liquid storage cup sleeves. A number of liquid injection through holes are arranged in a row on the positioning pressing plate. A number of the liquid storage cup sleeves are arranged on the side of the positioning pressing plate close to the tray, and a number of the liquid storage cup sleeves are connected and communicated with a number of the liquid injection through holes in one-to-one correspondence.

[0012] During use, a number of the liquid storage fixtures are placed above the tray, and each of the liquid storage cup sleeves is in cooperation and communication with the cell to be injected with liquid, so as to form a liquid storage space above the cell to be injected with liquid.

[0013] In one embodiment, a number of connecting through columns are integrally formed on the side of the positioning pressing plate close to the tray. Each of the connecting through columns is communicated with the liquid injection through hole, and each of the liquid storage cup sleeves is detachably sleeved on the corresponding connecting through column.

[0014] In one embodiment, each of the liquid storage cup sleeves is a hollow cylindrical structure. One end of the liquid injection cup sleeve is provided with a connecting portion for abutting and connecting with the open end of the cell to be injected with liquid, so that the liquid storage cup sleeve is connected and communicated with the cell to be injected with liquid.

[0015] In one embodiment, the connecting portion is provided with an annular inclined surface, and the horizontal diameter of the annular inclined surface decreases sequentially from top to bottom. The annular inclined surface abuts against the open end of the cell to be injected with liquid.

[0016] In one embodiment, a number of first positioning columns are further arranged on the side of the positioning pressing plate close to the tray. A number of first limiting holes are opened on the tray and are matched with the positions of the first positioning columns. When the liquid storage fixture is placed on the tray, a number of the first positioning columns are inserted into the corresponding first limiting holes one by one.

[0017] In one embodiment, the base assembly includes a base plate, a bracket and a number of limiting strips. The bracket is used to support the base plate. A number of the limiting strips are arranged on the upward-facing side of the base plate. A number of the limiting strips enclose a U-shaped limiting area, and the tray is placed in the U-shaped limiting area.

[0018] In one embodiment, a number of second positioning columns are arranged on the side of the tray close to the base plate. A number of second limiting holes are opened on the base plate and are matched with the positions of the second positioning columns. When the tray is placed on the base plate, a number of the second positioning columns are inserted into the second limiting holes one by one.

[0019] In one of the embodiments, the base assembly further includes a plurality of fasteners. When the liquid storage fixture is placed in alignment on the tray, the plurality of fasteners are used to lock and connect the liquid storage fixture and the base assembly.

[0020] In one of the embodiments, the plurality of limiting strips include a first limiting strip and a second limiting strip. The first limiting strip and the second limiting strip are arranged at intervals at both ends of the substrate. A plurality of the fasteners are respectively arranged in an aligned manner on the first limiting strip and the second limiting strip. Both ends of each liquid storage fixture are respectively locked and connected to the base assembly through one of the fasteners.

[0021] In one of the embodiments, when the liquid storage fixture is placed on the tray, the positioning pressing plate is horizontally arranged above the first limiting strip and the second limiting strip. The fastener is a buckle structure. Clamping portions are respectively arranged at both ends of the positioning pressing plate. When locking, the buckle structure is buckled and connected with the clamping portions.

[0022] Compared with the prior art, the utility model has at least the following advantages:

[0023] 1. Increasing the single injection volume and improving the injection efficiency: The traditional method of injecting a small amount of liquid in batches has greatly reduced the production efficiency due to the cumbersome operation. However, through the additional liquid storage fixture of the utility model, each liquid storage cup sleeve can be accurately docked with the battery cell to be injected, forming a relatively closed liquid storage space. This design allows for a significant increase in the injection volume each time while ensuring the uniform distribution of the electrolyte, thereby greatly reducing the required number of injection times, directly improving the overall efficiency of the injection process, and reducing the time cost.

[0024] 2. Optimizing the liquid storage space design to prevent liquid leakage: The tight fit between the liquid storage cup sleeve and the battery cell to be injected ensures precise control during the injection process, avoiding the spillage of the electrolyte caused by splashing or improper operation during the injection process, effectively preventing the liquid leakage phenomenon, reducing the electrolyte pollution and waste, and keeping the working environment clean at the same time.

[0025] 3. Improving the sealing effect and ensuring the welding quality: Through the pre-established closed liquid storage space before injection, the contact between the electrolyte and the battery cell is more orderly and controllable, avoiding the direct intrusion of the electrolyte into the welding area. In the subsequent sealing and welding steps, since the influence of the electrolyte is minimized, the one-time success rate of welding can be significantly improved, ensuring the airtightness of the steel shell and the overall safety of the battery, and reducing the product scrapping caused by poor welding. Description of the Drawings

[0026] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the accompanying drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present utility model and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0027] Figure 1 Structural schematic diagram of an auxiliary liquid injection device according to an embodiment of the present utility model;

[0028] Figure 2 Structural schematic diagram of a material tray according to an embodiment of the present utility model;

[0029] Figure 3 Structural schematic diagram of a base assembly according to an embodiment of the present utility model;

[0030] Figure 4 Structural schematic diagram of a liquid storage fixture according to an embodiment of the present utility model;

[0031] Figure 5 Exploded structural schematic diagram of a liquid storage fixture according to an embodiment of the present utility model;

[0032] The reference numerals in the figure are: 10, auxiliary liquid injection device; 100, material tray; 110, first limiting hole; 120, second positioning post; 200, base assembly; 210, substrate; 211, second limiting hole; 220, bracket; 230, limiting strip; 240, fastener; 300, liquid storage fixture; 310, positioning pressing plate; 311, liquid injection through hole; 312, connecting through post; 313, first positioning post; 314, engaging portion; 320, liquid storage cup sleeve; 321, annular inclined surface. Detailed implementation manners

[0033] To facilitate the understanding of the present utility model, the present utility model will be described more comprehensively below with reference to the relevant accompanying drawings. The preferred embodiments of the present utility model are shown in the drawings. However, the present utility model can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present utility model more thorough and comprehensive.

[0034] Please refer to Figures 1 to 4, an auxiliary liquid injection device (10), comprising: a material tray (100), a base assembly (200) and a plurality of liquid storage fixtures (300). The material tray (100) is used for arranging and placing the cells to be liquid-injected; the base assembly (200) is used for limiting and fixing the material tray (100); each liquid storage fixture (300) includes a positioning pressing plate (310) and a plurality of liquid storage cup sleeves (320). A plurality of liquid injection through holes (311) are arranged in the positioning pressing plate (310) in an array. The plurality of liquid storage cup sleeves (320) are arranged on the side of the positioning pressing plate (310) close to the material tray (100), and the plurality of liquid storage cup sleeves (320) are connected and communicated with the plurality of liquid injection through holes (311) in one-to-one correspondence; during use, the plurality of liquid storage fixtures (300) are placed above the material tray (100), and each liquid storage cup sleeve (320) cooperates and communicates with the cell to be liquid-injected to form a liquid storage space above the cell to be liquid-injected.

[0035] It should be noted that the auxiliary liquid injection device (10) is composed of a material tray (100), a base assembly (200) and a plurality of liquid storage fixtures (300). The functions of each part are clear, easy to assemble and disassemble, and convenient for maintenance and replacement. The material tray (100) is used for arranging and placing the cells to be liquid-injected to ensure the stable position of the cells during the liquid injection process; the base assembly (200) is used for limiting and fixing the material tray (100) to prevent movement or deviation during the liquid injection process and ensure the accuracy of liquid injection. Each liquid storage fixture (300) includes a positioning pressing plate (310) and a plurality of liquid storage cup sleeves (320). Liquid injection through holes (311) are arranged in the positioning pressing plate (310) in an array. This design enables the liquid storage cup sleeves (320) to closely cooperate with the cells to be liquid-injected to form an independent liquid storage space. During liquid injection, the electrolyte enters the liquid storage cup sleeves (320) through the liquid injection through holes (311) and is then uniformly injected into the cells, effectively avoiding waste and pollution of the electrolyte. Since the liquid storage fixture (300) can form a liquid storage space above the cell to be liquid-injected, the liquid injection work of a large number of cells can be completed once or a few times, significantly improving the liquid injection efficiency and reducing the production cost.

[0036] The usage method of the auxiliary liquid injection device (10) is as follows: After the baking process of the cells is completed, the cells are individually placed into the material tray (100) and arranged neatly. Subsequently, the material tray (100) containing the cells is securely placed in the base assembly (200) to ensure its stability during subsequent operations. A plurality of liquid storage fixtures (300) are arranged and placed corresponding to the upper part of the material tray (100) to ensure that each liquid storage cup sleeve (320) can closely cooperate with the cell to be liquid-injected to form a connected liquid injection channel. Then, quantitative perfusion of the electrolyte is started. After the liquid injection process is completed, during the waiting process for the electrolyte to infiltrate, the entire auxiliary liquid injection device (10) can be selected to be placed in a vacuum chamber. By applying a negative pressure environment, the absorption capacity of the wound core for the electrolyte is further enhanced, the infiltration speed of the electrolyte is increased, and the overall liquid injection time is further shortened.

[0037] Please refer to Figure 4 and Figure 5 , further, a plurality of connecting through columns (312) are integrally formed on one side of the positioning pressing plate (310) close to the tray (100), and each connecting through column (312) communicates with the liquid injection through hole (311). Each liquid storage cup sleeve (320) is detachably sleeved on the corresponding connecting through column (312).

[0038] It should be noted that a plurality of connecting through columns (312) are integrally formed on one side of the positioning pressing plate (310) close to the tray (100). These connecting through columns (312) not only communicate with the liquid injection through hole (311), but also serve as the supporting structure of the liquid storage cup sleeve (320). Each liquid storage cup sleeve (320) is designed to be detachable, and can be flexibly sleeved on the corresponding connecting through column (312), and can be disassembled and replaced as needed. This design enables the liquid storage fixture (300) to be adapted to different diameters of the battery cells. In practical applications, since the diameters of the battery cells may vary, the traditional fixed-size liquid injection cup sleeve may not meet the liquid injection requirements of all battery cells. However, with the detachable liquid storage cup sleeve (320) design of this device, the appropriate size of the liquid injection cup sleeve can be replaced according to the actual diameter of the battery cell, thereby ensuring the smooth progress of the liquid injection process, expanding the applicable range of the fixture, and improving the versatility and flexibility of the equipment.

[0039] Please refer to Figure 4 and Figure 5 , further, each liquid storage cup sleeve (320) is a hollow cylindrical structure, and a connecting portion is provided at one end of the liquid injection cup sleeve. The connecting portion is used to abut and connect with the open end of the battery cell to be injected with liquid, so that the liquid storage cup sleeve (320) is hermetically connected to the battery cell to be injected with liquid.

[0040] It should be noted that when the liquid storage cup sleeve (320) is placed above the battery cell to be injected with liquid, under the pressure of the positioning pressing plate (310), the connecting portion will closely fit with the open end of the battery cell, forming a sealed connection environment. This sealed connection not only effectively prevents the leakage and contamination of the electrolyte during the liquid injection process, but also ensures that the electrolyte can be accurately injected into the battery cell, improving the accuracy and quality of the liquid injection. In addition, the sealed connection between the liquid storage cup sleeve (320) and the battery cell also helps to reduce the entry of air bubbles and impurities into the battery cell during the liquid injection process, thereby further improving the performance and stability of the battery cell.

[0041] Please refer to Figure 4 and Figure 5 , further, the connecting portion is provided with an annular inclined surface (321), the horizontal diameter of the annular inclined surface (321) decreases sequentially from top to bottom, and the annular inclined surface (321) abuts against the open end of the battery cell to be injected with liquid.

[0042] It should be noted that the connecting part undertakes the important task of tightly connecting with the open end of the cell to be filled with liquid. To further optimize this connection effect, the connecting part is specially provided with an annular inclined surface (321), whose horizontal diameter gradually decreases from top to bottom, forming an inclined contact surface. The gradual fitting of the annular inclined surface (321) with the open end of the cell, by virtue of its gradually changing diameter design, can automatically adapt to the contour of the cell opening, forming a tight sealing interface. Even if there are slight differences in the cell opening, a good sealing effect can be achieved through the elastic deformation of the inclined surface, reducing the dependence on the strict dimensional consistency of the cells. At the same time, due to the guiding function of the annular inclined surface (321), precise alignment is not required during assembly, and the operator can complete the docking of the liquid storage cup sleeve (320) and the cell more quickly, greatly improving the production assembly efficiency and reducing the operation difficulty and time cost.

[0043] Please refer to Figure 4 and Figure 5 Furthermore, a number of first positioning posts (313) are provided on the side of the positioning pressing plate (310) close to the material tray (100), and a number of first limiting holes (110) matching the positions of the first positioning posts (313) are opened on the material tray (100). When the liquid storage fixture (300) is placed on the material tray (100), the first positioning posts (313) are inserted into the corresponding first limiting holes (110) one by one.

[0044] It should be noted that through the precise docking of the first positioning posts (313) and the first limiting holes (110) preset on the material tray (100), the absolute position accuracy of the liquid storage fixture (300) on the material tray (100) is ensured. Even during frequent production operations, each installation can be quickly and accurately in place, avoiding inaccurate liquid injection or cell damage caused by the offset of the fixture position. At the same time, the stability of the liquid storage fixture (300) during the liquid injection process is significantly enhanced, reducing the liquid injection errors that may be caused by vibration or accidental movement, which is crucial for ensuring the uniformity of liquid injection and the consistency of battery quality.

[0045] Please refer to Figure 3 Furthermore, the base assembly (200) includes a base plate (210), a bracket (220) and a number of limiting strips (230). The bracket (220) is used to support the base plate (210), and a number of limiting strips (230) are arranged on the upward-facing side of the base plate (210). The number of limiting strips (230) enclose a U-shaped limiting interval, and the material tray (100) is placed in the U-shaped limiting interval.

[0046] It should be noted that several limiting bars (230) are arranged on the upward-facing side of the substrate (210). The U-shaped limiting interval formed by their enclosure provides an accurate placement position for the tray (100), effectively preventing the tray (100) from sliding or shifting during placement or operation, ensuring the neat arrangement of the battery cells and the accuracy of the liquid injection operation. At the same time, the structural design of the U-shaped limiting interval simplifies the installation and removal process of the tray (100). The staff only needs to simply place the tray (100) into or take it out of the limiting interval, without complex alignment or fixing operations, greatly improving the convenience of operation and work efficiency.

[0047] Please refer to Figure 2 , Further, several second positioning posts (120) are arranged on the side of the tray (100) close to the substrate (210). Several second limiting holes (311) matching the positions of the second positioning posts (120) are provided on the substrate (210). When the tray (100) is placed on the substrate (210), several second positioning posts (120) are inserted into the second limiting holes (311) one by one.

[0048] It should be noted that the cooperation of the second positioning posts (120) and the second limiting holes (311) realizes the rapid positioning between the tray (100) and the substrate (210), and also effectively prevents the tray (100) from moving or shifting during the liquid injection process, thus ensuring the accuracy of liquid injection and the stability of the battery cells.

[0049] Please refer to Figure 3 , Further, the base assembly (200) further includes several fasteners (240). When the liquid storage fixture (300) is placed in alignment on the tray (100), several fasteners (240) are used to lock and connect the liquid storage fixture (300) and the base assembly (200).

[0050] It should be noted that several fasteners (240) are added to the base assembly (200). After the liquid storage fixture (300) is placed in alignment on the tray (100), these fasteners (240) can firmly lock and connect it with the base assembly (200). The addition of the fasteners (240) ensures the stability of the liquid storage fixture (300) during the liquid injection process. Even if there are pressure fluctuations or slight vibrations during the liquid injection process, it can effectively prevent the liquid storage fixture (300) from moving or misaligning, avoiding the potential risk of electrolyte leakage and improving the safety of operation.

[0051] Please refer to Figure 3, Further, a plurality of limiting strips (230) include a first limiting strip and a second limiting strip. The first limiting strip and the second limiting strip are arranged at intervals at both ends of the substrate (210). A plurality of fasteners (240) are respectively arranged in corresponding positions on the first limiting strip and the second limiting strip. Both ends of each liquid storage fixture (300) are respectively locked and connected to the base assembly (200) through a fastener (240). That is, through the limiting effect on both sides, the balance and stability of the liquid storage fixture (300) in the horizontal direction are ensured, and the inclination or displacement caused by unilateral force is avoided.

[0052] Please refer to Figure 1 , Further, when the liquid storage fixture (300) is placed on the tray (100), the positioning pressing plate (310) is horizontally arranged above the first limiting strip and the second limiting strip. The fastener (240) is a buckle structure. Clamping portions (314) are respectively arranged at both ends of the positioning pressing plate (310). When locking, the buckle structure is buckled and connected with the clamping portions (314).

[0053] It should be noted that clamping portions (314) are respectively arranged at both ends of the positioning pressing plate (310), and these clamping portions (314) are matched with the buckle structure. When locking, simply buckling the buckle structure with the clamping portions (314) can achieve the firm fixation of the liquid storage fixture (300) and the base assembly (200). This design not only improves the installation and disassembly efficiency but also reduces the labor intensity of the operator.

[0054] The above embodiments only represent several implementation manners of the present utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the utility model patent shall be subject to the appended claims.

Claims

1. An auxiliary liquid injection device, characterized in that: include: A material tray, the material tray is used to arrange and place the battery cells to be filled with liquid; A base assembly, the base assembly is used to limit and fix the material tray; A plurality of liquid storage jigs, each of which comprises a positioning plate and a plurality of liquid storage cup sleeves, wherein the positioning plate is provided with a plurality of liquid injection holes, the plurality of liquid storage cup sleeves are arranged on a side of the positioning plate close to the material tray, and the plurality of liquid storage cup sleeves are connected and penetrated with the plurality of liquid injection holes in a one-to-one correspondence; When in use, a plurality of the liquid storage jigs are placed above the material tray, and each of the liquid storage cup sleeves is connected to the battery cell to be filled with liquid, so as to form a liquid storage space above the battery cell to be filled with liquid.

2. The auxiliary liquid injection device according to claim 1, characterized in that: A plurality of connecting through-columns are integrally formed on one side of the positioning pressing plate close to the material tray, each of the connecting through-columns is connected to the liquid injection through-hole, and each of the liquid storage cup sleeves is detachably sleeved on a corresponding connecting through-column.

3. The auxiliary liquid injection device according to claim 2, characterized in that: Each of the liquid storage cup sleeves is a hollow cylindrical structure, and a connecting portion is provided at one end of the liquid injection cup sleeve, and the connecting portion is used to abut and connect with the open end of the battery cell to be injected, so that the liquid storage cup sleeve and the battery cell to be injected are through-sealed and connected.

4. The auxiliary liquid injection device according to claim 3, characterized in that: The connecting portion is provided with an annular bevel, the horizontal diameter of which decreases from top to bottom, and the annular bevel abuts against the open end of the battery cell to be injected with liquid.

5. The auxiliary liquid injection device according to claim 1, characterized in that: A plurality of first positioning columns are also provided on one side of the positioning plate close to the material tray, and a plurality of first limiting holes matching the positions of the first positioning columns are opened on the material tray. When the liquid storage fixture is placed on the material tray, the plurality of first positioning columns are inserted into the corresponding first limiting holes one by one.

6. The auxiliary liquid injection device according to claim 1, characterized in that: The base assembly includes a substrate, a bracket and a plurality of limit bars, the bracket is used to support the substrate, the plurality of limit bars are arranged on the upward side of the substrate, the plurality of limit bars together form a U-shaped limit interval, and the material tray is placed in the U-shaped limit interval.

7. The auxiliary liquid injection device according to claim 6, characterized in that: A plurality of second positioning posts are arranged on one side of the material tray close to the substrate, and a plurality of second limiting holes matching the positions of the second positioning posts are opened on the substrate. When the material tray is placed on the substrate, the plurality of second positioning posts are inserted into the second limiting holes one by one.

8. The auxiliary liquid injection device according to claim 6, characterized in that: The base assembly also includes a plurality of fasteners. When the liquid storage fixture is placed on the material tray, the plurality of fasteners are used to lock and connect the liquid storage fixture and the base assembly.

9. The auxiliary liquid injection device according to claim 8, characterized in that: The plurality of limit strips include a first limit strip and a second limit strip, the first limit strip and the second limit strip are spaced apart at both ends of the substrate, the first limit strip and the second limit strip are respectively arranged with a plurality of fasteners, and both ends of each of the liquid storage fixtures are respectively locked and connected to the base assembly through a fastener.

10. The auxiliary liquid injection device according to claim 9, characterized in that: When the liquid storage fixture is placed on the material tray, the positioning pressure plate is horizontally arranged above the first limit strip and the second limit strip, the fastener is a buckle structure, and both ends of the positioning pressure plate are respectively provided with a clamping part. When locked, the buckle structure is buckled and connected with the clamping part.

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