Battery liquid injection device and battery liquid injection method

Abstract

The invention provides a battery liquid injection device and a battery liquid injection method, and relates to the technical field of batteries. The battery liquid injection device comprises a shell, a liquid injection pipe and a vacuumizing assembly, the shell is provided with a cavity, and the shell is configured to be arranged at an opening of a battery cell of a battery to be injected in a sealed and sleeved mode, so that the cavity is communicated with the interior of the battery to be injected. The liquid injection pipe comprises a liquid injection port and a liquid outlet, the liquid injection pipe penetrates through the shell and extends into the battery to be injected, the liquid injection port is located outside the shell, and the liquid outlet is located in the battery to be injected. The vacuumizing assembly is arranged on the shell, and the vacuumizing end of the vacuumizing assembly communicates with the cavity. The battery cell opening of the to-be-injected battery is sealed by the shell, the electrolyte is directly injected into the to-be-injected battery by the electrolyte injection pipe, a pressurization process is omitted, and the whole battery cell opening does not need to be exposed to air, so that the injection of the electrolyte can be realized, and the contact amount and the contact area of the air and the electrolyte can be reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery liquid filling device and a battery liquid filling method. Background Art

[0002] In the related art, when injecting electrolyte into cylindrical batteries, the injected electrolyte will gather on the surface of the cylindrical batteries, and repeated pressurization and vacuuming are required to allow the electrolyte to completely penetrate into the cylindrical batteries. During the repeated vacuuming and pressurization of the batteries, the openings of the cells will be repeatedly exposed to the air, causing the batteries to corrode and leak. Summary of the invention

[0003] The embodiments of the present application provide a battery filling device and a battery filling method, which are used to improve the technical problem of battery corrosion and leakage during the filling process of cylindrical batteries.

[0004] In a first aspect, an embodiment of the present application provides a battery injection device for injecting electrolyte into a battery to be injected, the battery injection device comprising:

[0005] A shell having a cavity, wherein the shell is configured to be sleeved on the cell opening of the battery to be filled with liquid, and the shell is sealed and connected to the cell opening so that the cavity is connected to the interior of the battery to be filled with liquid;

[0006] A liquid injection pipe, comprising a liquid injection port and a liquid outlet, the liquid injection pipe passes through the shell and extends into the interior of the battery to be injected, the liquid injection port is located outside the shell, and the liquid outlet is located inside the battery to be injected;

[0007] A vacuum pumping component is arranged on the shell, and a vacuum pumping end of the vacuum pumping component is communicated with the cavity.

[0008] In some embodiments of the present application, the vacuum assembly includes:

[0009] Vacuum power source;

[0010] A vacuum pipe is disposed in the housing and one end of the vacuum pipe is connected to the vacuum power source, and the other end of the vacuum pipe is disposed in the cavity;

[0011] The vacuum valve is arranged on the vacuum pipeline and is used to control the opening and closing of the vacuum pipeline.

[0012] In some embodiments of the present application, the liquid injection pipe includes a liquid inlet section, a liquid outlet section and a middle section, the two sides of the middle section are respectively connected to the liquid inlet section and the liquid outlet section, a part of the liquid inlet section is located outside the shell, and a part is located in the cavity, the liquid outlet section is located inside the battery to be injected, the liquid outlet is provided at one end of the liquid outlet section away from the middle section, and the liquid injection port is provided at one end of the liquid inlet section away from the middle section;

[0013] Wherein, the middle section is in the shape of an inverted cone.

[0014] In some embodiments of the present application, the liquid outlet is located at the inner bottom of the battery to be filled with liquid.

[0015] In a second aspect, an embodiment of the present application provides a battery injection method, comprising:

[0016] The shell sealing sleeve is arranged at the cell opening of the battery to be filled with liquid, so that the cavity of the shell is connected with the interior of the battery to be filled with liquid;

[0017] Inserting the injection tube into the battery to be injected and injecting electrolyte to a preset liquid volume;

[0018] Turning on the vacuum pumping component to perform vacuum pumping on the interior of the battery to be filled with liquid until the interior of the battery to be filled with liquid reaches a preset vacuum degree;

[0019] Maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time;

[0020] Closing the vacuum assembly;

[0021] Repeat the steps after arranging the shell sealing sleeve at the opening of the battery cell of the battery to be filled with liquid until the battery to be filled with liquid is filled with a preset total amount of electrolyte and the battery cells in the battery to be filled with liquid are completely infiltrated with the electrolyte.

[0022] In some embodiments of the present application, the preset liquid volume is at least one tenth of the preset total electrolyte volume.

[0023] In some embodiments of the present application, the vacuum pumping assembly includes a vacuum power source, a vacuum pipe and a vacuum valve, wherein the vacuum pipe is disposed in the housing and one end of the vacuum pipe is connected to the vacuum power source, and the other end of the vacuum pipe is disposed in the cavity, and the vacuum valve is disposed in the vacuum pipe to control the opening and closing of the vacuum pipe;

[0024] The step of starting the vacuum pumping component and performing vacuum pumping on the interior of the battery to be filled with liquid until the interior of the battery to be filled with liquid reaches a preset vacuum degree includes:

[0025] Opening the vacuum power source and the vacuum valve to evacuate the interior of the battery to be filled with liquid;

[0026] The time for vacuuming reaches a second preset time, and the vacuum degree inside the battery to be filled reaches a preset vacuum degree.

[0027] In some embodiments of the present application, the step of maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time includes:

[0028] The power of the vacuum power source and / or the opening of the vacuum valve are adjusted so that the rate of air entering the battery to be filled is consistent with the rate of vacuuming, so as to maintain the preset vacuum degree for a first preset time.

[0029] In some embodiments of the present application, the second preset time ranges from 4 seconds to 7 seconds, and the first preset time ranges from 40 seconds to 60 seconds.

[0030] In some embodiments of the present application, before the step of maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time, the step further includes:

[0031] The vacuum pumping assembly is used to release the pressure inside the battery to be filled with liquid, so that the pressure inside the battery to be filled with liquid is balanced with the pressure outside the battery to be filled with liquid.

[0032] Beneficial effects of the embodiments of the present application:

[0033] The present application provides a battery filling device and a battery filling method. The battery filling device seals the opening of the battery to be filled with liquid by using a shell, and the filling tube extends into the interior of the battery to be filled with liquid, and the electrolyte is directly injected into the interior of the battery to be filled through the filling tube. It can not only realize the injection of electrolyte, but also reduce the amount and contact area of ​​air entering the interior of the battery to be filled with liquid and contacting the electrolyte. Only the filling tube and the vacuum pumping component of the battery cell inside the battery to be filled can enter the air. Compared with the related art, directly exposing the opening of the battery to be filled to the air can effectively reduce the contact area between air and electrolyte. In addition, by using the vacuum pumping component to vacuum the interior of the battery to be filled, there is no need to set up a pressurizing device for the entire process, and there is no pressurizing process, that is, there will be no repeated pressurization and vacuum pumping process. While simplifying the process, it also avoids the situation where the core and electrolyte of the battery to be filled need to be exposed to the air for a long time. In detail, first, the shell and the cell opening are sealed to block external air from entering the battery to be filled as much as possible, reducing the contact area between air and electrolyte; then, a liquid injection tube is extended through the shell to the battery to be filled, and the liquid outlet of the liquid injection tube is located inside the battery to be filled, so that the electrolyte can directly contact the winding core inside the battery to be filled after being injected into the battery to be filled through the liquid injection tube, thereby accelerating the infiltration of the electrolyte, and during the liquid injection process, only the part of the liquid injection tube may be mixed with air, effectively reducing the amount of air entering the battery to be filled, and reducing the contact area between air and electrolyte. Also, after the electrolyte is injected, the inside of the battery to be filled is evacuated to a vacuum environment by using a vacuum pumping component, and the principle of pressure is used to accelerate the infiltration of the electrolyte, so that the electrolyte can cover various positions inside the battery to be filled as much as possible, and accelerate the infiltration into the winding core, thereby improving the electrolyte infiltration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic diagram of a battery liquid filling device provided in an embodiment of the present application;

[0035] Figure 2 It is a flow chart of a battery filling method provided in an embodiment of the present application.

[0036] Description of reference numerals:

[0037] 1. Battery to be filled with liquid; 11. Winding core; 2. Battery filling device; 21. Shell; 211. Cavity; 22. Filling pipe; 221. Liquid inlet section; 222. Middle section; 223. Liquid outlet section; 23. Vacuum extraction component; 231. Vacuum pipe; 232. Vacuum valve. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise stated, the directional words such as "upper" and "lower" used generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0039] See also Figure 1 , an embodiment of the present application provides a battery injection device for injecting electrolyte into a battery 1 to be injected, the battery injection device comprises a shell 21, an injection tube 22 and a vacuum assembly 23. The shell 21 is provided with a cavity 211, and the shell 21 is configured as a sealing sleeve disposed at the cell opening of the battery 1 to be injected, so that the cavity 211 is connected with the interior of the battery 1 to be injected. The injection tube 22 comprises an injection port and an outlet, the injection tube 22 passes through the shell 21 and extends into the interior of the battery 1 to be injected, the injection port is located outside the shell 21, and the outlet is located inside the battery 1 to be injected. The vacuum assembly 23 is disposed on the shell 21, and the vacuum end of the vacuum assembly 23 is connected with the cavity 211.

[0040] The technical solution provided by the present application uses the shell 21 to seal the opening of the battery 1 to be filled with liquid, and the injection tube 22 extends into the interior of the battery 1 to be filled with liquid, and the electrolyte is directly injected into the interior of the battery 1 to be filled with liquid through the injection tube 22. It can not only realize the injection of electrolyte, but also reduce the amount and contact area of ​​air entering the interior of the battery 1 to be filled with liquid and contacting the electrolyte. Only the injection tube 22 and the vacuum assembly 23 of the battery inside the battery 1 to be filled with liquid can enter the air. Compared with the related art, directly exposing the opening of the battery 1 to be filled with liquid to the air can effectively reduce the contact area between air and electrolyte. In addition, by using the vacuum assembly 23 to vacuum the interior of the battery 1 to be filled with liquid, there is no need to set up a pressurizing device for the entire process, and there is no pressurizing process, that is, there will be no repeated pressurization and vacuuming process. While simplifying the process, it also avoids the situation where the winding core 11 and the electrolyte of the battery 1 to be filled need to be exposed to the air for a long time. In detail, first, the shell 21 and the cell opening are sealed to prevent external air from entering the battery 1 to be filled as much as possible, reducing the contact area between air and electrolyte; then, the injection tube 22 is extended through the shell 21 to the battery 1 to be filled, and the liquid outlet of the injection tube 22 is located inside the battery 1 to be filled, so that the electrolyte can be directly contacted with the winding core 11 inside the battery 1 to be filled after being injected into the battery 1 through the injection tube 22, thereby accelerating the infiltration of the electrolyte, and during the injection process, only the injection tube 22 may be mixed with air, effectively reducing the amount of air entering the battery 1 to be filled, and reducing the contact area between air and electrolyte. And, after the electrolyte is injected, the vacuum assembly 23 is used to evacuate the inside of the battery 1 to be filled into a vacuum environment, and the principle of pressure is used to accelerate the infiltration of the electrolyte, so that the electrolyte can cover various positions inside the battery 1 to be filled as much as possible, and accelerate the infiltration into the winding core 11, thereby improving the electrolyte infiltration efficiency.

[0041] It should be noted that the sealing sleeve of the shell 21 on the opening of the battery cell is mainly realized by utilizing the structure of the battery 1 to be filled with liquid. Specifically, the battery cell is wound into a winding core 11 by a winding machine, and then the battery 1 to be filled with liquid is transported to the assembly process, and the winding core 11 is put into the shell and the shell is shrunk. After the shrinkage, the head of the shell of the battery 1 to be filled with liquid will form an arc structure that is concave inward, and the shell 21 can be sleeved on the head of the shell and sealed with the concave part.

[0042] In some embodiments, the vacuum pumping assembly 23 includes a vacuum power source (not shown in the figure), a vacuum pipe 231 and a vacuum valve 232. The vacuum pipe 231 is arranged in the shell 21 and one end of the vacuum pipe 231 is connected to the vacuum power source, and the other end is arranged in the cavity 211. The vacuum valve 232 is arranged in the vacuum pipe 231, and is used to control the opening and closing of the vacuum pipe 231. It should be noted that for the vacuum power source, a vacuum pump or other equipment that can play a vacuum pumping role can be selected. The vacuum power source does not need to be arranged on the shell 21, and its position can be selected near the battery 1 to be filled with liquid, or it can be arranged at a position far away from the battery 1 to be filled with liquid, without limitation, as long as the vacuum pipe 231 connected to the vacuum power source is connected to the inside of the battery 1 to be filled with liquid.

[0043] Furthermore, multiple vacuum pipes 231 may be provided, such as two in the present embodiment, and a vacuum valve 232 is provided for each vacuum pipe 231. By providing two vacuum pipes 231, the vacuuming efficiency can be effectively improved, thereby accelerating the infiltration of the electrolyte and improving the injection efficiency. Compared with providing more vacuum pipes 231, the two vacuum pipes 231 are simpler to control, and only two vacuum valves 232 need to be controlled. The two vacuum pipes 231 can also be connected to the same vacuum power source, such as a vacuum pump. The two vacuum pipes 231 are respectively located on both sides of the injection pipe 22, and are symmetrically arranged with the injection pipe 22 as the axis of symmetry, which is conducive to a more balanced and stable vacuuming process, so that the electrolyte in the battery 1 to be injected can also infiltrate the battery cell more evenly.

[0044] In some embodiments, the injection tube 22 includes a liquid inlet section 221, a liquid outlet section 223 and an intermediate section 222. Both sides of the intermediate section 222 are connected to the liquid inlet section and the liquid outlet section 223, respectively. A portion of the liquid inlet section 221 is located outside the housing 21 for easy access to the liquid injection device, and a portion is located inside the cavity 211. The liquid outlet section 223 is located inside the battery 1 to be injected, and a liquid outlet is provided at one end of the liquid outlet section 223 away from the intermediate section 222, and a liquid injection port is provided at one end of the liquid inlet section away from the intermediate section 222. The liquid outlet section 223 is arranged inside the battery to be filled 1, so that the electrolyte can directly enter the battery to be filled 1 through the liquid outlet pipe, and the sealing sleeve of the shell 21 is arranged on the opening of the battery cell, which greatly reduces the area of ​​the electrolyte and the inside of the battery to be filled 1 that contacts the air. During the liquid filling stage, air can only enter the battery to be filled 1 through the liquid filling pipe 22, and the amount of air entering is limited, and the area of ​​the electrolyte that the air can contact is also limited, which effectively prevents moisture in the air from reacting with lithium hexafluoride in the electrolyte to generate hydrogen fluoride, and then effectively avoids hydrogen fluoride from causing corrosion damage to the inside of the battery to be filled 1.

[0045] Furthermore, the middle section 222 is in an inverted cone shape. In other words, the flow rate of the middle section 222 gradually decreases along the injection direction, which can play a buffering role in the injection process, as well as temporarily storing the electrolyte and facilitating the injection of the electrolyte from the liquid inlet section 221 into the middle section 222.

[0046] In some embodiments, the liquid outlet is located at the inner bottom of the battery to be filled 1. Compared with setting the liquid outlet close to the top of the battery to be filled 1, it is more conducive to the electrolyte to continuously rise and infiltrate from the bottom to the top, and can avoid the liquid outlet being too close to the battery cell opening, causing the electrolyte to overflow during the filling process.

[0047] Based on the battery liquid filling device disclosed in the above embodiment, the embodiment of the present application also provides a battery liquid filling method, which is mainly implemented by the battery liquid filling device provided in the above embodiment. Figure 2 , the battery filling method comprises:

[0048] S1. Place a shell sealing sleeve on the cell opening of the battery to be filled with liquid, so that the cavity of the shell is connected with the interior of the battery to be filled with liquid.

[0049] The shell 21 is sealed and sleeved at the cell opening of the battery 1 to be filled with liquid, so as to seal the cell opening, thereby preventing the cell opening from being completely exposed to the air during the subsequent liquid filling process, and preventing a large amount of air from entering the interior of the battery 1 to be filled with liquid and reacting with the electrolyte, causing the interior of the battery 1 to be filled with liquid to be corroded by the generated hydrogen fluoride. The cavity 211 of the shell 21 is connected to the interior of the battery 1 to be filled with liquid, providing the necessary conditions for the subsequent liquid filling tube 22 to extend into the interior of the battery 1 to be filled with liquid and to evacuate the interior of the battery 1 to be filled with liquid.

[0050] S2. Insert the injection tube into the battery to be injected and inject electrolyte to a preset liquid volume.

[0051] The injection tube 22 is passed through the shell 21 and extended to the inside of the battery 1 to be injected. The external injection equipment is connected to the injection tube 22 and the injection equipment is started. The electrolyte is injected into the battery 1 to be injected through the injection tube 22. During the entire injection process, the electrolyte will not be exposed to the external environment, which is beneficial to ensure the purity of the electrolyte during the injection process.

[0052] Furthermore, the preset liquid volume is at least one tenth of the preset total electrolyte volume. In order to improve the injection efficiency, the preset liquid volume can be directly set to be equal to the preset total electrolyte volume, that is, only one injection process is required, and other subsequent processes only need to be performed once. However, in this way, overflow may occur, and the uniformity of electrolyte infiltration will be reduced, and some positions of the core 11 may not be fully infiltrated with the electrolyte. Therefore, in this embodiment, preferably, the preset liquid volume is one fifth of the preset total electrolyte volume, that is, the subsequent injection needs to be performed a total of five times, compared to one tenth, it can not only reduce the number of processes and improve efficiency, but also avoid overflow and improve the uniformity of electrolyte infiltration of the core 11.

[0053] S3, start the vacuum pumping component to vacuum the inside of the battery to be filled with liquid until the inside of the battery to be filled with liquid reaches a preset vacuum degree.

[0054] By utilizing the vacuum pumping assembly 23, the interior of the battery 1 to be filled is vacuumed to achieve a preset vacuum degree. At this time, under the action of the pressure difference between the inside and outside of the battery 1 to be filled, the electrolyte is pressurized and can better cover various parts of the winding core 11, so that the electrolyte is evenly infiltrated into various parts of the winding core 11, and some positions of the winding core 11, such as the gap between the winding core 11 and the inner wall of the shell of the battery 1 to be filled, are avoided as much as possible without the infiltration of the electrolyte.

[0055] Specifically, the vacuum pumping assembly 23 includes a vacuum power source, a vacuum pipe 231 and a vacuum valve 232. The vacuum pipe 231 is provided in the housing 21 and one end of the vacuum pipe 231 is connected to the vacuum power source, and the other end is provided in the cavity 211. The vacuum valve 232 is provided in the vacuum pipe 231 to control the opening and closing of the vacuum pipe 231. The step of opening the vacuum pumping assembly 23 and performing vacuum pumping on the inside of the battery 1 to be filled with liquid until the inside of the battery 1 to be filled with liquid reaches a preset vacuum degree includes:

[0056] Open the vacuum power source and the vacuum valve 232 to evacuate the interior of the battery 1 to be filled with liquid, so that the air inside the battery 1 to be filled with liquid is evacuated to form a vacuum environment;

[0057] When the vacuum treatment time reaches the second preset time, the vacuum degree inside the battery 1 to be filled reaches the preset vacuum degree. At this time, the vacuum degree inside the battery 1 to be filled can put pressure on the electrolyte, so that the electrolyte can completely infiltrate the winding core 11 as much as possible, and can avoid damage to the battery 1 to be filled due to excessive pressure inside.

[0058] S4, maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time.

[0059] When the vacuum degree inside the battery 1 to be filled reaches the preset vacuum degree, it is necessary to keep the vacuum degree inside the battery 1 to be filled for a certain period of time. During this period of time, the electrolyte will gradually infiltrate the core 11 to improve the uniformity of the electrolyte infiltration. Compared with waiting for the electrolyte to slowly infiltrate the core 11, by utilizing pressure, the electrolyte can infiltrate the core 11 more quickly, and can also be forced to enter some more difficult gaps under the action of pressure to increase the area of ​​the core 11 infiltrated by the electrolyte.

[0060] Furthermore, the step of maintaining the vacuum degree inside the battery 1 to be filled with liquid at a preset vacuum degree for a first preset time includes:

[0061] The power of the vacuum power source and / or the opening of the vacuum valve 232 are adjusted so that the rate of air entering the battery 1 to be filled is consistent with the rate of vacuuming, so as to maintain the preset vacuum degree for a first preset time.

[0062] In order to allow the electrolyte inside the battery 1 to be filled to fully infiltrate the winding core 11, it is necessary to use the vacuum environment to apply pressure to the electrolyte so that the electrolyte can infiltrate the winding core 11 more evenly and quickly. However, when the vacuum degree inside the battery 1 to be filled reaches the preset vacuum degree, if the vacuum power of the vacuum power source is not adjusted, and the opening of the vacuum valve 232 is not adjusted, the inside of the battery 1 to be filled will continue to be vacuumed, breaking the preset vacuum degree, which may cause damage to the battery 1 to be filled. If both the vacuum power source and the vacuum valve 232 are closed, the vacuum environment inside the battery 1 to be filled will also be destroyed due to the entry of air into the injection pipe 22, affecting the infiltration of the electrolyte. Therefore, this embodiment adopts one or both of the methods of adjusting the power of the vacuum power source and the opening of the vacuum valve 232 to achieve the same rate of vacuuming inside the battery 1 to be filled as the rate of air entering the battery 1 to be filled, so as to achieve that the vacuum degree inside the battery 1 to be filled is always maintained at the preset vacuum degree, ensuring the rapid infiltration of the electrolyte.

[0063] Furthermore, the second preset time range of the vacuum treatment is 4 seconds to 7 seconds, and is set to 6 seconds in this embodiment. The second preset time is mainly calculated based on the respective parameter settings of the preset vacuum degree, vacuum power source and vacuum valve 232. As long as the vacuum power source and the vacuum valve 232 parameters are kept unchanged for each subsequent vacuuming, it can be ensured that the preset vacuum degree is reached inside the battery 1 to be filled with liquid when the vacuum is evacuated to the second preset time. There is no need to set a detector for monitoring the vacuum degree in the battery 1 to be filled with liquid, which saves costs and reduces the difficulty of detection. The first preset time ranges from 40 seconds to 60 seconds. In this embodiment, the first preset time is selected as 50 seconds. During these 50 seconds, the vacuum degree in the battery 1 to be filled with liquid always maintains the preset vacuum degree, so that the electrolyte has enough power and time to infiltrate the winding core 11.

[0064] S5. Turn off the vacuum assembly.

[0065] S6, repeating the steps after placing the shell sealing sleeve on the opening of the battery cell of the battery to be filled with liquid, until the battery to be filled with liquid is filled with a preset total amount of electrolyte and the battery cells in the battery to be filled with liquid are completely infiltrated with the electrolyte.

[0066] By dividing the injection process into multiple cycles, it is helpful to avoid the electrolyte overflowing from the battery 1 to be injected, and each injection must go through the stages of injection, vacuuming, and maintaining vacuum, which helps to strengthen the infiltration of the electrolyte and improve the uniformity of the electrolyte infiltration of the winding core 11.

[0067] In some embodiments, before the step of maintaining the vacuum degree inside the battery 1 to be filled with liquid at a preset vacuum degree for a first preset time, the step further includes:

[0068] The vacuum assembly 23 is used to release the pressure inside the battery 1 to be filled with liquid, so that the pressure inside the battery 1 to be filled with liquid is balanced with the pressure outside the battery 1 to be filled with liquid.

[0069] Specifically, the vacuum power source is turned off, and the vacuum valve 232 remains open. At this time, the air outside the battery 1 to be filled with liquid will enter the battery 1 to be filled with liquid through the liquid filling tube 22 and the vacuum pipe 231, thereby balancing the pressure inside and outside the battery 1 to be filled with liquid, and restoring the internal air pressure of the battery 1 to be filled with liquid to normal. The normal state refers to a state that is equal to or approximately equal to the atmospheric pressure outside the battery 1 to be filled with liquid, which is conducive to protecting the battery 1 to be filled from damage due to excessive pressure, and providing conditions for subsequent multiple vacuuming and liquid filling processes. After the internal pressure of the battery 1 to be filled with liquid is restored to normal, continue the next liquid filling cycle.

[0070] To facilitate understanding of the specific process of the above-mentioned injection method, the above-mentioned steps are summarized as an example below:

[0071] The shell 21 is sealed and placed on the opening of the battery cell of the battery 1 to be filled with liquid, so that the cavity 211 of the shell 21 is connected with the inside of the battery 1 to be filled with liquid, and then the injection tube 22 is inserted into the battery 1 to be filled with liquid and the electrolyte is injected to a preset liquid volume, which is one fifth of the total amount of the preset electrolyte; then the vacuum pump and the vacuum valve 232 are turned on to evacuate the inside of the battery 1 to be filled with liquid until the vacuum degree inside the battery 1 to be filled with liquid reaches the preset vacuum degree, and the vacuum treatment time is 6 seconds; then the power of the vacuum pump is reduced. The rate is increased and the opening of the vacuum valve 232 is reduced, so that the vacuuming rate is equal to the rate at which air enters the battery 1 to be filled through the injection pipe 22, thereby balancing the vacuum degree inside the battery 1 to be filled, so that the vacuum degree always maintains the preset vacuum degree for 50 seconds; then the vacuum pump is turned off, and the vacuum valve 232 is still kept open, so that the air outside the battery 1 to be filled enters the battery 1 to be filled, so as to achieve the purpose of pressure relief. The pressure relief lasts for 15 seconds, and then the vacuum valve 232 is closed to complete the first injection process.

[0072] After the first injection process, continue to inject electrolyte to the preset liquid volume. At this time, the amount of electrolyte in the battery 1 to be injected is two-fifths of the preset total amount of electrolyte; then open the vacuum pump and the vacuum valve 232 to evacuate the interior of the battery 1 to be injected until the vacuum degree inside the battery 1 to be injected reaches the preset vacuum degree. The vacuum treatment time is 6 seconds; then reduce the power of the vacuum pump and reduce the opening of the vacuum valve 232 to make the vacuum pumping rate equal to the rate at which air enters the battery 1 to be injected through the injection pipe 22, thereby balancing the vacuum degree inside the battery 1 to be injected, so that the vacuum degree always remains at the preset vacuum degree for 50 seconds; then turn off the vacuum pump, and the vacuum valve 232 remains open, so that the air outside the battery 1 to be injected enters the battery 1 to be injected, so as to achieve the purpose of pressure relief. The pressure relief lasts for 15 seconds, and then close the vacuum valve 232 to complete the second injection process.

[0073] After the second liquid injection process, the electrolyte is continuously injected to the preset liquid volume. At this time, the electrolyte volume in the battery 1 to be injected is three-fifths of the preset total electrolyte volume; the vacuum pump and the vacuum valve 232 are turned on again to evacuate the interior of the battery 1 to be injected until the vacuum degree inside the battery 1 to be injected reaches the preset vacuum degree. The vacuum treatment time is 6 seconds; the power of the vacuum pump is reduced and the opening of the vacuum valve 232 is reduced so that the vacuum pumping rate is equal to the rate at which air enters the interior of the battery 1 to be injected through the liquid injection pipe 22, thereby balancing the vacuum degree inside the battery 1 to be injected, so that the vacuum degree always maintains the preset vacuum degree for 50 seconds; the vacuum pump is turned off again, and the vacuum valve 232 is still kept open, so that the air outside the battery 1 to be injected enters the interior of the battery 1 to be injected, so as to achieve the purpose of pressure relief. The pressure relief lasts for 15 seconds, and then the vacuum valve 232 is closed to complete the third liquid injection process.

[0074] After the third liquid injection process, the electrolyte is continuously injected to the preset liquid volume. At this time, the electrolyte volume in the battery 1 to be injected is four-fifths of the preset total electrolyte volume; the vacuum pump and the vacuum valve 232 are turned on again to evacuate the interior of the battery 1 to be injected until the vacuum degree inside the battery 1 to be injected reaches the preset vacuum degree. The vacuum treatment time is 6 seconds; the power of the vacuum pump is reduced and the opening of the vacuum valve 232 is reduced so that the vacuum pumping rate is equal to the rate at which air enters the interior of the battery 1 to be injected through the injection pipe 22, thereby balancing the vacuum degree inside the battery 1 to be injected, so that the vacuum degree always remains at the preset vacuum degree for 50 seconds; the vacuum pump is turned off again, and the vacuum valve 232 is still kept open, so that the air outside the battery 1 to be injected enters the interior of the battery 1 to be injected, so as to achieve the purpose of pressure relief. The pressure relief lasts for 15 seconds, and then the vacuum valve 232 is closed to complete the fourth liquid injection process.

[0075] The fourth injection process continues, and the electrolyte is continued to be injected to the preset liquid volume. At this time, the amount of electrolyte in the battery 1 to be injected is equal to the preset total amount of electrolyte; then the vacuum pump and the vacuum valve 232 are turned on to evacuate the inside of the battery 1 to be injected until the vacuum degree inside the battery 1 to be injected reaches the preset vacuum degree, and the vacuum treatment time is 6 seconds; then the power of the vacuum pump is reduced and the opening of the vacuum valve 232 is reduced to make the vacuum pumping rate equal to the rate at which air enters the battery 1 to be injected through the injection pipe 22, thereby balancing the vacuum degree inside the battery 1 to be injected, so that the vacuum degree always maintains the preset vacuum degree for 50 seconds; then the vacuum pump is turned off, and the vacuum valve 232 is still kept open, so that the air outside the battery 1 to be injected enters the battery 1 to be injected, so as to achieve the purpose of pressure relief, and the pressure relief lasts for 15 seconds, and then the vacuum valve 232 is closed to complete the entire injection process.

[0076] Through the above five times of liquid injection, vacuuming and pressure relief process, the total time consumed is 355 seconds. In the related art, the steps include the process of pressurization, as well as the process of continuous liquid injection, vacuuming and pressure relief. The total time consumed by the experiment is 1051 seconds. Obviously, the technical solution provided by this application can significantly improve the liquid injection efficiency of the battery to be injected. Of course, when comparing this solution with the solution in the related art, the preset vacuum degree needs to be set to be equal as a constant for comparing the time consumption. In this experiment, the vacuum degree is set to -95 kPa. Of course, when comparing other experiments, the vacuum degree can also be set to less than -95 kPa.

[0077] The embodiments of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A battery injection device for injecting electrolyte into a battery to be injected, characterized in that: The battery injection device comprises: A shell having a cavity, wherein the shell is configured to be sleeved on the cell opening of the battery to be filled with liquid, and the shell is sealed and connected to the cell opening so that the cavity is connected to the interior of the battery to be filled with liquid; A liquid injection pipe, comprising a liquid injection port and a liquid outlet, the liquid injection pipe passes through the shell and extends into the interior of the battery to be injected, the liquid injection port is located outside the shell, and the liquid outlet is located inside the battery to be injected; A vacuum pumping component is arranged on the shell, and a vacuum pumping end of the vacuum pumping component is communicated with the cavity.

2. The battery liquid injection device according to claim 1, characterized in that: The vacuum assembly comprises: Vacuum power source; A vacuum pipe is disposed in the housing and one end of the vacuum pipe is connected to the vacuum power source, and the other end of the vacuum pipe is disposed in the cavity; The vacuum valve is arranged on the vacuum pipeline and is used to control the opening and closing of the vacuum pipeline.

3. The battery liquid injection device according to claim 1, characterized in that: The injection pipe comprises a liquid inlet section, a liquid outlet section and a middle section, the two sides of the middle section are respectively connected with the liquid inlet section and the liquid outlet section, a part of the liquid inlet section is located outside the shell, and a part of the liquid outlet section is located inside the battery to be injected, the liquid outlet is provided at one end of the liquid outlet section away from the middle section, and the injection port is provided at one end of the liquid inlet section away from the middle section; Wherein, the middle section is in the shape of an inverted cone.

4. The battery liquid injection device according to claim 1, characterized in that: The liquid outlet is located at the inner bottom of the battery to be filled with liquid.

5. A battery filling method, characterized in that: include: The shell sealing sleeve is arranged at the cell opening of the battery to be filled with liquid, so that the cavity of the shell is connected with the interior of the battery to be filled with liquid; Inserting the injection tube into the battery to be injected and injecting electrolyte to a preset liquid volume; Turning on the vacuum pumping component to perform vacuum pumping on the interior of the battery to be filled with liquid until the vacuum degree inside the battery to be filled with liquid reaches a preset vacuum degree; Maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time; Closing the vacuum assembly; Repeat the steps after arranging the shell sealing sleeve at the opening of the battery cell of the battery to be filled with liquid until the battery to be filled with liquid is filled with a preset total amount of electrolyte and the battery cells in the battery to be filled with liquid are completely infiltrated with the electrolyte.

6. The battery injection method according to claim 5, characterized in that: The preset liquid volume is at least one tenth of the preset total electrolyte volume.

7. The battery injection method according to claim 5, characterized in that: The vacuum pumping assembly includes a vacuum power source, a vacuum pipeline and a vacuum valve. The vacuum pipeline is arranged in the housing and one end of the vacuum pipeline is connected to the vacuum power source, and the other end is arranged in the cavity. The vacuum valve is arranged in the vacuum pipeline and is used to control the opening and closing of the vacuum pipeline. The step of starting the vacuum pumping component and performing vacuum pumping on the interior of the battery to be filled with liquid until the interior of the battery to be filled with liquid reaches a preset vacuum degree includes: Opening the vacuum power source and the vacuum valve to evacuate the interior of the battery to be filled with liquid; The time for vacuuming reaches a second preset time, and the vacuum degree inside the battery to be filled reaches a preset vacuum degree.

8. The battery injection method according to claim 7, characterized in that: The step of maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time includes: The power of the vacuum power source and / or the opening of the vacuum valve are adjusted so that the rate of air entering the battery to be filled is consistent with the rate of vacuuming, so as to maintain the preset vacuum degree for a first preset time.

9. The battery filling method according to claim 8, characterized in that: The second preset time ranges from 4 seconds to 7 seconds, and the first preset time ranges from 40 seconds to 60 seconds.

10. The battery injection method according to claim 7, characterized in that: Before the step of maintaining the vacuum degree inside the battery to be filled with liquid at a preset vacuum degree for a first preset time, the step further includes: The vacuum pumping assembly is used to release the pressure inside the battery to be filled with liquid, so that the pressure inside the battery to be filled with liquid is balanced with the pressure outside the battery to be filled with liquid.

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