Battery liquid injection apparatus and battery liquid injection method

Abstract

The application discloses a battery liquid injection equipment and a battery liquid injection method. The battery liquid injection equipment comprises an outer cover, a liquid injection assembly, a liquid level detection assembly, a gas pressure adjusting assembly and a control assembly. The liquid injection assembly is arranged in the outer cover and comprises a liquid injection cup. The liquid injection cup is a light-transmitting piece. The liquid level detection assembly comprises an image receiver and a light-emitting unit. The image receiver and the light-emitting unit are located on opposite sides of the liquid injection cup along a first direction. The gas pressure adjusting assembly is used for adjusting the pressure in the outer cover. The control assembly is used for receiving images acquired by the image receiver and controlling the gas pressure adjusting assembly to adjust the pressure in the outer cover. According to the battery liquid injection equipment, the liquid level of electrolyte in the liquid injection cup can be acquired, and whether there is active substance falling off in the battery can be detected. Therefore, accurate data support can be provided for battery liquid injection rate calculation and cell failure judgment, and the reliability of the liquid injection process performed by the battery liquid injection equipment can be improved.

Description

Technical Field

[0001] This invention relates to the field of battery manufacturing technology, and in particular to a battery electrolyte filling device and a battery electrolyte filling method. Background Technology

[0002] With the continuous development of the new energy industry, batteries are widely used in various fields. For example, lithium iron phosphate batteries require an electrolyte filling process during production, where electrolyte fills the pores of the battery cell, serving as a medium for lithium ion flow. However, in related technologies, it is impossible to know the electrolyte filling status of the battery in a timely and accurate manner, leading to the failure of battery electrolyte filling to be detected in a timely manner. Summary of the Invention

[0003] The first aspect of this invention proposes a battery electrolyte filling device, which can obtain the electrolyte level in the filling cup and detect whether there are active materials detached from the battery in the electrolyte, thereby providing accurate data support for battery electrolyte filling rate calculation and cell failure judgment.

[0004] According to a first aspect of the present invention, a battery electrolyte filling device includes: an outer casing; an electrolyte filling assembly disposed within the outer casing and including an electrolyte filling cup, the electrolyte filling cup being for storing electrolyte and adapted to be connected to a battery, the electrolyte filling cup being a light-transmitting element; a liquid level detection assembly including an image receiver and a light-emitting unit, the image receiver and the light-emitting unit being located on opposite sides of the electrolyte filling cup along a first direction, the light-emitting unit being for emitting light toward the electrolyte filling cup along the first direction, the first direction being perpendicular to the vertical direction; a pressure regulating assembly connected to the outer casing and for regulating the pressure inside the outer casing; and a control assembly for receiving an image acquired by the image receiver and controlling the pressure regulating assembly to regulate the pressure inside the outer casing.

[0005] According to the battery liquid injection device of the first aspect of the present invention, by arranging the image receiver and the light-emitting unit on opposite sides of the liquid injection cup along the first direction, the liquid level of the electrolyte in the liquid injection cup and the presence of active material detached from the battery in the electrolyte can be obtained, thereby providing accurate data support for battery liquid injection rate calculation and cell failure judgment, and thus improving the reliability of the liquid injection process performed by the battery liquid injection device.

[0006] According to some embodiments of the present invention, the light-emitting unit is a flash lamp; and / or, both the image receiver and the light-emitting unit are fixed to the outer cover.

[0007] According to some embodiments of the present invention, the liquid injection assembly includes a battery holder for holding a battery, the liquid injection cup being detachably disposed on the upper side of the battery holder, and the battery being connected to the lower side of the liquid injection cup.

[0008] According to some embodiments of the present invention, the air pressure regulating assembly includes an air intake device, an air pressure detection device, and a vacuum negative pressure device. The air intake device and the vacuum negative pressure device are both in communication with the interior of the outer casing. The air intake device is used to supply gas into the outer casing, and the vacuum negative pressure device is used to discharge gas from the outer casing. The air pressure detection device is located inside the outer casing, and the air intake device, the air pressure detection device, and the vacuum negative pressure device are all electrically connected to the control unit.

[0009] According to some embodiments of the present invention, the air pressure detection device is located at the top of the outer cover, and the connection positions of the air intake device and the outer cover, as well as the connection positions of the vacuum negative pressure device and the outer cover, are all located at the bottom of the outer cover.

[0010] According to some embodiments of the present invention, the air intake device includes an air storage tank, an air intake pipe, and an air intake solenoid valve. The air storage tank is connected to the interior of the outer casing through the air intake pipe. The air intake solenoid valve is located on the air intake pipe and is used to control the flow rate of the air intake pipe. The vacuum negative pressure device includes a vacuum pump, an exhaust pipe, and an exhaust solenoid valve. The vacuum pump is connected to the interior of the outer casing through the exhaust pipe. The exhaust solenoid valve is located on the exhaust pipe and is used to control the flow rate of the exhaust pipe. Both the air intake solenoid valve and the exhaust solenoid valve are electrically connected to the control unit.

[0011] A second aspect of the present invention provides a battery electrolyte injection method.

[0012] According to a second aspect of the present invention, a battery electrolyte filling method includes: connecting a battery to an electrolyte filling cup and placing it inside an outer casing; performing an electrolyte filling process; detecting whether solid particles are present in the electrolyte in the electrolyte filling cup; adjusting the rate of change of air pressure inside the outer casing and the rate of change of liquid level inside the electrolyte filling cup during the electrolyte filling process based on whether solid particles are present in the electrolyte in the electrolyte filling cup; and completing the electrolyte filling process when there is no electrolyte in the electrolyte filling cup.

[0013] According to a second aspect of the present invention, in the electrolyte injection method, the rate of change of air pressure inside the outer casing and the rate of change of liquid level inside the injection cup are adjusted according to whether there are solid particles in the electrolyte inside the injection cup. This can ensure the efficiency of electrolyte injection into the battery while avoiding damage to the battery cell due to excessively fast electrolyte injection speed.

[0014] The outer casing is connected to an air inlet pipe and an air outlet pipe. The liquid injection process includes alternating positive pressure and negative pressure stages. During the positive pressure stage, gas is supplied to the outer casing through the air inlet pipe, and during the negative pressure stage, gas is discharged from the outer casing through the air outlet pipe. The air inlet pipe is equipped with an air inlet solenoid valve, and the air outlet pipe is equipped with an air outlet solenoid valve. Adjusting the rate of change of air pressure inside the outer casing during the liquid injection process includes controlling the opening degree of the air inlet solenoid valve and the air outlet solenoid valve.

[0015] According to some embodiments of the present invention, when solid particles are detected in the electrolyte of the injection cup, the opening degree of the air intake solenoid valve or the exhaust solenoid valve is reduced; when no solid particles are detected in the electrolyte of the injection cup, the air intake solenoid valve and the exhaust solenoid valve are maintained at their current opening degree.

[0016] According to some embodiments of the present invention, the opening degree of the intake solenoid valve and the exhaust solenoid valve decreases by no more than 10% in a single operation.

[0017] According to some embodiments of the present invention, when solid particles are detected in the electrolyte of the injection cup, the reduction in the opening degree of the air intake solenoid valve and the exhaust solenoid valve is controlled according to the distribution density of the solid particles in the electrolyte.

[0018] According to some embodiments of the present invention, the positive pressure stage includes a first pressure boosting stage, a second pressure boosting stage, and a pressure stabilizing stage performed sequentially, wherein the opening degree of the intake solenoid valve increases sequentially during the first pressure boosting stage, the second pressure boosting stage, and the pressure stabilizing stage.

[0019] According to some embodiments of the present invention, in the first pressurization stage, the opening degree of the intake solenoid valve is not greater than one-fifth of the maximum opening degree of the intake solenoid valve; and / or, in the second pressurization stage, the opening degree of the intake solenoid valve gradually increases until the opening degree of the intake solenoid valve reaches the maximum opening degree.

[0020] According to some embodiments of the present invention, during the voltage stabilization phase, the pressure inside the outer casing remains unchanged, and the battery liquid injection method further includes: obtaining the pressure value inside the outer casing, wherein the pressure during the first pressure boosting phase is a first pressure, the pressure during the voltage stabilization phase is a second pressure, and when the first pressure reaches a first pressure threshold, a second pressure boosting phase is entered, wherein the first pressure threshold and the second pressure satisfy P1 / P2≥0.4.

[0021] According to some embodiments of the present invention, the air intake rate in the first pressurization stage is not greater than 5 kPa / s; and / or, in the first pressurization stage, the liquid level drop rate in the injection cup is not greater than 15 mm / s.

[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a battery electrolyte filling device according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the electrolyte injection assembly and battery of a battery electrolyte injection device according to an embodiment of the present invention; Figure 3 This is a schematic flowchart of a battery electrolyte injection method according to an embodiment of the present invention.

[0025] Figure label: 100. Battery filling equipment; 1. Outer casing; 2. Filling assembly; 21. Filling cup; 22. Battery holder; 221. Base; 222. First claw; 223. Second claw; 3. Liquid level detection assembly; 31. Image receiver; 32. Light-emitting unit; 41. Air intake device; 411. Air tank; 412. Air intake pipe; 413. Air intake solenoid valve; 42. Air pressure detection device; 43. Vacuum negative pressure device; 431. Vacuum pump; 432. Exhaust pipe; 433. Exhaust solenoid valve; 10. Battery. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0027] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. Additionally, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0028] In the description of this invention, 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," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0029] In the description of this invention, "first feature" and "second feature" may include one or more of the features.

[0030] In the description of this invention, "a plurality of" means two or more.

[0031] In the description of this invention, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0032] In the description of this invention, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicating that the first feature is at a higher horizontal level than the second feature.

[0033] A battery electrolyte filling device 100 according to a first aspect of the present invention will now be described with reference to the accompanying drawings.

[0034] like Figure 1 and Figure 2 As shown, a battery electrolyte filling device 100 according to a first aspect embodiment of the present invention includes: an outer cover 1, an electrolyte filling assembly 2, a liquid level detection assembly 3, a pressure regulating assembly 4, and a control assembly. The electrolyte filling assembly 2 is disposed inside the outer cover 1 and includes an electrolyte filling cup 21. The electrolyte filling cup 21 is used to store electrolyte and is adapted to be connected to a battery 10. The electrolyte filling cup 21 is a light-transmitting element. The liquid level detection assembly 3 includes an image receiver 31 and a light-emitting unit 32. The image receiver 31 and the light-emitting unit 32 are located on opposite sides of the electrolyte filling cup 21 along a first direction (e1 as shown in the figure). The light-emitting unit 32 is used to emit light toward the electrolyte filling cup 21 along the first direction, which is perpendicular to the vertical direction. The pressure regulating assembly is connected to the outer cover 1 and is used to regulate the pressure inside the outer cover 1. The control assembly is used to receive the image acquired by the image receiver 31 and control the pressure regulating assembly 4 to regulate the pressure inside the outer cover 1.

[0035] For example, the control component is electrically connected to the liquid level detection component 3 and the air pressure regulating component 4 and includes an image processing unit and a control unit. The image processing unit is used to receive and process the image acquired by the image receiver 31, and the control unit is used to receive the processing result of the image processing unit and control the air pressure regulating component 4 to adjust the pressure inside the outer cover 1 according to the processing result of the image processing unit.

[0036] In other words, after the image receiver 31 acquires the image of the injection cup 21 under the illumination of the light-emitting unit 32, it sends the acquired image to the image processing unit. The image processing unit can analyze and process the image and obtain the corresponding parameters of the electrolyte in the injection cup 21 (including but not limited to the electrolyte level and whether there are still solid particles, etc.). The control unit can generate control logic according to the corresponding parameters of the electrolyte in the injection cup 21 and send the control signal corresponding to the control logic to the air pressure regulating component 4 so that the air pressure regulating component 4 can execute the corresponding action.

[0037] In other words, the control component receives and processes the images acquired by the image receiver 31, and controls the operating state of the pressure regulating component 4 to adjust the pressure inside the outer casing 1, thereby realizing the process of injecting liquid into the battery 10. For example, the pressure inside the outer casing 1 can be increased by the pressure regulating component. The injection cup 21 has a communication port that communicates with the cavity inside the outer casing 1. For example, the top of the injection cup 21 can be open. After the injection cup 21 is connected to the battery 10, the liquid storage chamber inside the injection cup 21 is connected to the inside of the battery 10. As the pressure inside the outer casing 1 gradually increases, the pressure in the space above the electrolyte surface increases, causing the electrolyte to be pushed into the battery 10 under the action of pressure difference. In a specific example, the control component is a control computer, which is electrically connected to the image receiver 31 and the pressure regulating component to receive the images acquired by the image receiver 31 and issue control commands to the pressure regulating component 4.

[0038] Among them, the liquid injection cup 21 is a light-transmitting component, that is, the liquid injection cup 21 can transmit light. The control component can control the operation of the image receiver 31 and the light-emitting unit 32. After the light-emitting unit 32 emits light from one side of the liquid injection cup 21 along the first direction, the light can pass through the liquid injection cup 21 and illuminate the image receiver 31, so that the image receiver 31 can receive the projected image of the liquid injection cup 21 under the illumination of the light-emitting unit 32. Because different media have different transmittance, the brightness of the projection produced by light passing through the electrolyte in the injection cup 21 and passing through the gas (specifically, the gas located above the electrolyte surface in the injection cup 21) is different. The boundary between the two areas with different brightness is the electrolyte surface in the injection cup 21. Therefore, the electrolyte surface in the injection cup 21 can be accurately obtained through the projected image received by the image receiver 31. By continuously obtaining the electrolyte surface in the injection cup 21, the rate of electrolyte descent in the injection cup 21 can be obtained, and thus the rate at which electrolyte is injected into the battery 10 from the injection cup 21 can be obtained.

[0039] Furthermore, when the air intake rate inside the outer casing 1 is too fast, causing the pressure inside the outer casing 1 to rise rapidly, the high pressure pushes the electrolyte in the injection cup 21 to move at high speed into the battery 10. The air in the narrow slits inside the battery 10 is subjected to stress from the impact diffusion, which may cause the active material attached to the cell to detach. When the detached active material enters the electrolyte in the injection cup 21 from inside the battery 10, since the active material is usually in the form of fixed particles, a black dot is formed at the location of the active material in the image received by the image receiver 31. In other words, the presence of active material in the electrolyte in the injection cup 21 can be determined by the projected image received by the image receiver 31. When active material is present in the electrolyte in the injection cup 21, it indicates that the cell has failed. In subsequent production processes, the injection parameters can be adjusted until no active material remains in the electrolyte.

[0040] That is, the electrolyte level in the injection cup 21 can be obtained through the liquid level detection device, and the presence of active material detached from the battery 10 in the electrolyte can also be detected. This provides accurate data support for the electrolyte injection rate of the battery 10 and the cell failure of the battery 10, thereby improving the reliability of the electrolyte injection process performed by the battery injection equipment 100. It should be noted that the image receiver 31 can be a camera with a CMOS image sensor. The light emitted by the light-emitting unit 32 is projected onto the CMOS image sensor through the projection of the injection cup 21. The CMOS image sensor can convert the projection into an image output, which is convenient for subsequent feature comparison and classification to obtain the electrolyte level and the active material in the electrolyte.

[0041] According to the battery filling device 100 of the first aspect of the present invention, by arranging the image receiver 31 and the light-emitting unit 32 on opposite sides of the filling cup 21 along the first direction, the liquid level of the electrolyte in the filling cup 21 can be obtained and the presence of active material detached from the battery 10 in the electrolyte can be detected. This can provide accurate data support for calculating the filling rate of the battery 10 and judging cell failure, thereby improving the reliability of the filling process performed by the battery filling device 100.

[0042] In some embodiments of the present invention, the light-emitting unit 32 is a flash lamp. That is, the light-emitting unit 32 can flash light at a set frequency to enhance the contrast between light and dark and provide a momentarily high-brightness shooting environment, thereby improving the clarity of the image projected onto the image receiver 31 through the liquid filling cup 21, and further improving the accuracy of detecting the electrolyte level and active substances in the electrolyte based on the image. In a specific example, the flash frequency of the flash lamp is 5 m / s. That is, an image is acquired once every 5 seconds, so that the rate of electrolyte level drop can be obtained based on the liquid level difference between the images captured by two flashes.

[0043] In some embodiments of the present invention, both the image receiver 31 and the light-emitting unit 32 are fixed to the outer cover 1. This allows for better fixation of the image receiver 31 and the light-emitting unit 32, and maintains a stable relative position between the image receiver 31 and the light-emitting unit 32 and the liquid injection assembly 2. This improves the accuracy of obtaining the electrolyte level in the liquid injection cup 21 through the liquid level detection assembly 3 and detecting the presence of active material detached from the battery 10 in the electrolyte.

[0044] In some embodiments of the present invention, the liquid injection assembly 2 includes a battery holder 22 for holding the battery 10. The liquid injection cup 21 is detachably disposed on the upper side of the battery holder 22, and the battery 10 is connected to the lower side of the liquid injection cup 21. Thus, the connection between the liquid injection cup 21 and the battery 10 can be better secured by the battery holder 22, so as to ensure communication between the liquid injection cup 21 and the internal space of the battery 10 during the liquid injection process. In a specific example, the battery holder 22 includes a base 221, a first claw 222, and a second claw 223. The first claw 222 and the second claw 223 are rotatably disposed on the base 221 and located on opposite sides of the base 221 along a first direction. The base 221 is used to place the battery 10. Both the first claw 222 and the second claw 223 are provided with elastic elements, so that the length of the first claw 222 and the second claw 223 can be elastically adjusted. After the battery 10 is placed on the base 221 and the liquid filling cup 21 is connected to the battery 10, the first claw 222 and the second claw 223 can respectively hold the liquid filling cup 21 from opposite sides along the first direction to maintain the relative position between the liquid filling cup 21 and the battery holder 22.

[0045] In some embodiments of the present invention, the air pressure regulating assembly includes an air intake device 41, an air pressure detection device 42, and a vacuum negative pressure device 43. The air intake device 41 and the vacuum negative pressure device 43 are both connected to the interior of the outer cover 1. The air intake device 41 is used to supply gas into the outer cover 1, and the vacuum negative pressure device 43 is used to discharge gas from the outer cover 1. The air pressure detection device 42 is located inside the outer cover to detect the air pressure value inside the outer cover 1. The air intake device 41, the air pressure detection device 42, and the vacuum negative pressure device 43 are all electrically connected to the control unit.

[0046] In other words, by receiving the air pressure value inside the outer cover 1 detected by the air pressure detection device 42 through the control unit, the control unit can control the air intake device 41 and the vacuum negative pressure device 43 to perform corresponding actions based on the detected air pressure value inside the outer cover 1, thereby improving the automation level of the battery liquid filling equipment 100.

[0047] For example, the electrolyte injection process includes a positive pressure stage and a negative pressure stage. In the positive pressure stage, gas is introduced into the outer casing 1 through the air intake device 41 to increase the pressure inside the outer casing 1 and push the electrolyte into the battery 10. In the negative pressure stage, the gas inside the outer casing 1 is drawn out and discharged through the vacuum negative pressure device 43 to remove the gas from the battery 10, facilitating subsequent electrolyte injection. By obtaining the pressure value inside the outer casing 1, the rate of pressure change inside the outer casing 1 can be determined in conjunction with time. This allows for adjustment of the air intake or exhaust rate according to production requirements, preventing excessively rapid pressure changes inside the outer casing 1 that could damage the inside of the battery 10 and improving the safety of the electrolyte injection process.

[0048] Specifically, by setting up a vacuum negative pressure device 43, when the electrolyte is pushed into the battery 10 by pressurizing the gas supplied into the outer cover 1, since there is also some gas inside the battery 10, when the liquid level of the electrolyte in the injection cup 21 no longer continues to drop, the gas in the outer cover 1 can be extracted by the vacuum negative pressure device 43. When the pressure inside the outer cover 1 gradually decreases to a negative pressure state, the gas in the battery 10 is discharged through the injection cup 21. That is, the gas in the battery 10 can be extracted, and then the outer cover 1 can be pressurized again to push the electrolyte in the injection cup 21 into the battery 10. The above process is repeated until the electrolyte in the injection cup 21 is completely injected into the battery 10.

[0049] In some embodiments of the present invention, the air pressure detection device 42 is located at the top of the outer casing 1, while the connection points of the air intake device 41 and the vacuum negative pressure device 43 with the outer casing 1 are both located at the bottom of the outer casing 1. That is, the air intake device 41 supplies gas to the outer casing 1 at the bottom of the outer casing 1, and the vacuum negative pressure device 43 draws gas from the outer casing 1 at the bottom of the outer casing 1; in other words, the gas inlet and outlet of the outer casing 1 are located at the bottom of the outer casing 1. This increases the distance between the air pressure detection device 42 and the gas inlet and outlet of the outer casing 1, thus preventing the gas flow at the gas inlet and outlet of the outer casing 1 from affecting the detection accuracy of the air pressure detection device 42.

[0050] In some embodiments of the present invention, the air intake device 41 includes an air storage tank 411, an air intake pipe 412, and an air intake solenoid valve 413. The air storage tank 411 is connected to the interior of the outer cover 1 through the air intake pipe 412. The air intake solenoid valve 413 is located on the air intake pipe 412 and is used to control the flow rate of the air intake pipe 412. The vacuum negative pressure device 43 includes a vacuum pump 431, an exhaust pipe 432, and an exhaust solenoid valve 433. The vacuum pump 431 is connected to the interior of the outer cover 1 through the exhaust pipe 432. The exhaust solenoid valve 433 is located on the exhaust pipe 432 and is used to control the flow rate of the exhaust pipe 432. Both the air intake solenoid valve 413 and the exhaust solenoid valve 433 are electrically connected to the control unit.

[0051] In other words, the control unit can control the opening degree of the intake solenoid valve 413 to adjust the intake rate, and the control unit can control the opening degree of the exhaust solenoid valve 433 to adjust the vacuuming rate. Specifically, the intake solenoid valve 413 can control the opening or closing of the intake pipe 412, thereby controlling the gas supply from the gas tank 411 to the outer cover 1 or stopping the gas supply to the outer cover 1. Furthermore, when the intake solenoid valve 413 opens the intake pipe 412, the opening degree of the intake solenoid valve 413 can be controlled to control the rate at which the gas tank 411 supplies gas to the outer cover 1 through the intake pipe 412. That is, the intake rate of the outer cover 1 can be controlled by the intake solenoid valve 413. By installing the air pressure detection device 42 inside the outer casing 1, it is convenient to detect the pressure value inside the outer casing 1 in real time. For example, the air pressure detection device 42 can be an air pressure gauge. Through the electrical connection between the air pressure detection device 42 and the air intake solenoid valve 413, the air intake solenoid valve 413 can adjust its opening degree according to the pressure value detected by the air pressure detection device 42. That is, the air pressure detection and closed-loop control of the air intake rate inside the outer casing 1 can be realized, so as to improve the automation level of the battery liquid filling equipment 100.

[0052] Furthermore, the opening or closing of the exhaust pipe 432 can be controlled by the exhaust solenoid valve 433, thereby controlling the connection or disconnection between the vacuum pump 431 and the internal space of the outer casing 1. When the exhaust solenoid valve 433 opens the exhaust pipe 432, the opening degree of the exhaust solenoid valve 433 can be controlled to control the rate at which the vacuum pump 431 draws gas from the outer casing 1 through the exhaust pipe 432. That is, the exhaust rate of the outer casing 1 can be controlled by the exhaust solenoid valve 433.

[0053] In one specific example, the gas stored in the gas tank 411 is nitrogen.

[0054] A battery electrolyte injection method according to a second aspect of the present invention will now be described with reference to the accompanying drawings.

[0055] like Figure 3 As shown, the battery electrolyte injection method according to a second aspect embodiment of the present invention includes: connecting a battery 10 to an injection cup 21 and placing it inside an outer cover 1 to form a communicating injection channel between the battery 10 and the injection cup 21, so that the electrolyte in the injection cup 21 can be injected into the battery 10 through the injection channel formed between the injection cup 21 and the interior of the battery 10.

[0056] After the assembly of battery 10 and electrolyte cup 21 is placed inside the outer cover 1, an electrolyte injection process is performed to inject the electrolyte in electrolyte cup 21 into battery 10.

[0057] During the electrolyte filling process, the presence of solid particles in the electrolyte within the filling cup 21 is detected. During filling, if the air pressure inside the outer casing 1 changes too rapidly, the pressure difference between the inside of the battery 10 and the outer casing 1 changes drastically. This can easily cause the active material inside the battery 10 to detach and enter the electrolyte, appearing as solid particles. Therefore, the presence of solid particles in the electrolyte indicates that active material has detached, while the absence of solid particles indicates that no active material has detached. Thus, the presence of solid particles in the electrolyte within the filling cup 21 can be used to determine whether the electrolyte filling process has failed.

[0058] Furthermore, the rate of change of air pressure inside the outer casing 1 and the rate of change of liquid level inside the injection cup 21 are adjusted according to whether there are solid particles in the electrolyte inside the injection cup 21 during the injection process. The rate of change of air pressure inside the outer casing 1 refers to the air intake and exhaust rates of the outer casing 1, and the rate of change of liquid level inside the injection cup 21 refers to the rate of decrease or increase of the liquid level inside the injection cup 21. The faster the rate of change of air pressure inside the outer casing 1 and the rate of change of liquid level inside the injection cup 21, the faster the electrolyte enters the battery 10. When solid particles are present in the electrolyte inside the injection cup 21, it indicates that the current rate of change of air pressure inside the outer casing 1 and the rate of decrease of the liquid level inside the injection cup 21 are too fast, causing impact damage to the battery cells inside the battery 10.

[0059] When there are no solid particles in the electrolyte in the injection cup 21, it indicates that the rate of change of air pressure in the outer casing 1 and the rate of decrease of the liquid level in the injection cup 21 will not damage the battery cell. However, if the rate of change of air pressure in the outer casing 1 and the rate of change of the liquid level in the injection cup 21 are too low, the injection time will be prolonged. Therefore, by adjusting the rate of change of air pressure in the outer casing 1 and the rate of change of the liquid level in the injection cup 21 during the injection process according to whether there are solid particles in the electrolyte in the injection cup 21, it is possible to avoid damaging the battery cell by injecting the electrolyte too quickly while ensuring the efficiency of electrolyte injection into the battery 10.

[0060] When there is no electrolyte in the injection cup 21, the electrolyte filling is complete. When there is no electrolyte in the injection cup 21, it indicates that the electrolyte in the injection cup 21 has been completely injected into the battery 10, indicating that the battery 10 has completed the electrolyte filling process.

[0061] According to the battery electrolyte injection method of the second aspect of the present invention, in the electrolyte injection process, the rate of change of air pressure in the outer cover 1 and the rate of change of liquid level in the electrolyte injection cup 21 are adjusted according to whether there are solid particles in the electrolyte in the electrolyte injection cup 21. This can ensure the efficiency of electrolyte injection into the battery 10 while avoiding damage to the battery cell of the battery 10 due to excessively fast electrolyte injection speed.

[0062] In some embodiments, the battery electrolyte injection method can be applied to the battery electrolyte injection device 100 of the first aspect embodiment described above, that is, the battery electrolyte injection method is performed by the battery electrolyte injection device 100 of the first aspect embodiment to inject electrolyte into the battery. Specifically, the battery electrolyte injection method can be stored in a control component and executed by the control component. The outer cover 1 is the outer cover 1 of the battery electrolyte injection device 100. Connecting the battery 10 to the electrolyte injection cup 21 means that the battery 10 is installed in the electrolyte injection assembly 2 and the assembly of the battery 10 and the electrolyte injection assembly 2 is placed in the outer cover 1. The air intake rate in the outer cover 1 is obtained by the air pressure regulating component, and the liquid level in the electrolyte injection cup 21 is obtained by the liquid level detection component 3 and the presence of solid particles in the electrolyte in the electrolyte injection cup 21 is detected. By combining the detected liquid level change with time, the change in liquid level over time can be obtained, thereby obtaining the rate of decrease or increase of liquid level in the electrolyte injection cup 21. The control component is used to execute the battery electrolyte injection method.

[0063] According to some embodiments of the present invention, the outer cover 1 is connected to an air inlet pipe 412 and an exhaust pipe 432. The liquid injection process includes alternating positive pressure and negative pressure stages. In the positive pressure stage, gas is supplied into the outer cover 1 through the air inlet pipe 412. In the negative pressure stage, gas is discharged from the outer cover 1 through the exhaust pipe 432. An air inlet solenoid valve 413 is provided on the air inlet pipe 412, and an exhaust solenoid valve 433 is provided on the exhaust pipe 432. Adjusting the rate of change of air pressure in the outer cover 1 during the liquid injection process includes controlling the opening degree of the air inlet solenoid valve 413 and the exhaust solenoid valve 433.

[0064] The intake solenoid valve 413 can control the opening or closing of the intake pipe 412, thereby supplying or stopping gas supply to the outer casing 1. When the intake solenoid valve 413 opens the intake pipe 412, the rate at which gas is supplied to the outer casing 1 can be controlled by adjusting the opening degree of the intake solenoid valve 413; that is, the intake rate of the outer casing 1 can be controlled by the intake solenoid valve 413. Similarly, the exhaust solenoid valve 433 can control the opening or closing of the exhaust pipe 432. When the exhaust solenoid valve 433 opens the exhaust pipe 432, the rate at which gas is discharged from the outer casing 1 can be controlled by adjusting the opening degree of the exhaust solenoid valve 433; that is, the exhaust rate of the outer casing 1 can be controlled by the exhaust solenoid valve 433. Therefore, by controlling the opening degrees of the intake solenoid valve 413 and the exhaust solenoid valve 423, precise control of the intake and exhaust rates within the outer casing 1 can be achieved.

[0065] Specifically, during the negative pressure phase, the pressure inside the outer casing 1 is gradually reduced by extracting the gas until the outer casing 1 is in a negative pressure state. Since some gas also exists inside the battery 10, when the electrolyte level in the injection cup 21 stops decreasing during the pressure stabilization phase, the pressure stabilization phase ends and the negative pressure phase begins. By extracting the gas from the outer casing 1, as the pressure inside the outer casing 1 gradually decreases to a negative pressure state, the gas inside the battery 10 is discharged through the injection cup 21. That is, the gas inside the battery 10 can be extracted. Then, the first pressure boosting phase, the second pressure boosting phase, and the pressure stabilization phase can be repeated to pressurize the outer casing 1 again and push the electrolyte in the injection cup 21 into the battery 10.

[0066] According to some embodiments of the present invention, when solid particles are detected in the electrolyte of the injection cup 21, the opening degree of the inlet solenoid valve 413 or the exhaust solenoid valve 433 is reduced; when no solid particles are detected in the electrolyte of the injection cup 21, the inlet solenoid valve 413 or the exhaust solenoid valve 433 is kept at the current opening degree, and the rate of change of liquid level in the injection cup 21 is kept constant.

[0067] It should be noted that, during the positive pressure phase, when solid particles are detected in the electrolyte of the injection cup 21, the opening of the intake solenoid valve 413 is reduced; when no solid particles are detected in the electrolyte of the injection cup 21, the intake solenoid valve 413 is maintained at its current opening. During the negative pressure phase, when solid particles are detected in the electrolyte of the injection cup 21, the opening of the exhaust solenoid valve 433 is reduced; when no solid particles are detected in the electrolyte of the injection cup 21, the exhaust solenoid valve 433 is maintained at its current opening.

[0068] In other words, the presence of solid particles in the electrolyte within the injection cup 21 indicates that the current intake or exhaust rate is too high, causing impact damage to the battery cell. By reducing the intake rate during the positive pressure phase or the exhaust rate during the negative pressure phase, the rate at which the electrolyte is injected into the battery 10 can be reduced, thereby preventing the electrolyte from being injected too quickly and causing impact damage to the battery cell. When there are no solid particles in the electrolyte within the injection cup 21, it indicates that the current intake or exhaust rate will not cause impact damage to the battery cell. Therefore, the intake solenoid valve 413 is kept at its current opening during the positive pressure phase, and the exhaust solenoid valve 433 is kept at its current opening during the negative pressure phase.

[0069] It should be noted that when running the battery electrolyte injection method for the first time, the intake solenoid valve 413 can be opened to its maximum degree. By gradually reducing the opening of the intake solenoid valve 413 until there are no solid particles in the electrolyte, the rate at which the electrolyte is injected into the battery 10 can be increased, thereby shortening the time required for electrolyte injection into the battery 10. In other words, while avoiding damage to the battery cell due to excessively fast electrolyte injection speed, the efficiency of electrolyte injection into the battery 10 can be guaranteed.

[0070] According to some embodiments of the present invention, the opening degree of the intake solenoid valve 413 and the exhaust solenoid valve 433 decreases by no more than 10% in a single operation. That is, when solid particles are detected in the electrolyte of the injection cup 21, the opening degree of the intake solenoid valve 413 and the exhaust solenoid valve 433 decreases by a maximum of 10%. This avoids excessively large reductions in the opening degree of the intake solenoid valve 413 and the exhaust solenoid valve 433, which could lead to excessively slow intake and exhaust rates, affecting the injection efficiency and thus ensuring the injection rate.

[0071] According to some embodiments of the present invention, when solid particles are detected in the electrolyte of the injection cup 21, the reduction in the opening degree of the inlet solenoid valve 413 and the outlet solenoid valve 433 is controlled according to the density of the solid particles in the electrolyte. A higher density of solid particles in the electrolyte indicates more active material that has been impacted and detached from the battery cell, and also indicates a greater difference between the current inflow / outflow rate and the standard inflow / outflow rate (the rate at which the electrode liquid will not cause impact damage to the battery cell). Conversely, a lower density of solid particles in the electrolyte indicates less active material that has been impacted and detached from the battery cell, and a smaller difference between the current inflow / outflow rate and the standard inflow / outflow rate.

[0072] Therefore, based on the density of solid particles in the electrolyte, the reduction in the opening of the inlet solenoid valve 413 and the outlet solenoid valve 433 is controlled. Specifically, the higher the density of solid particles in the electrolyte, the greater the reduction in the opening of the inlet solenoid valve 413 and the outlet solenoid valve 433; conversely, the lower the density of solid particles in the electrolyte, the smaller the reduction in the opening of the inlet solenoid valve 413 and the outlet solenoid valve 433. This reduces the number of times the opening of the inlet solenoid valve 413 and the outlet solenoid valve 433 needs to be adjusted, thereby improving the efficiency of the battery electrolyte filling method. It should be noted that the density of solid particles in the electrolyte is obtained from the density of points representing solid particles in the image acquired by the image receiver 31.

[0073] According to some embodiments of the present invention, the positive pressure stage includes a first pressure-boosting stage, a second pressure-boosting stage, and a pressure-stabilizing stage performed sequentially. During the first pressure-boosting stage, the second pressure-boosting stage, and the pressure-stabilizing stage, the opening degree of the intake solenoid valve 413 increases sequentially. That is, the opening degree of the intake solenoid valve 413 in the second pressure-boosting stage is greater than that in the first pressure-boosting stage, but less than that in the pressure-stabilizing stage. As the positive pressure stage progresses, the pressure inside the outer casing 1 increases. By increasing the opening degree of the intake solenoid valve 413, sufficient air intake rates can be ensured during the second pressure-boosting stage and the pressure-stabilizing stage, allowing the pressure inside the outer casing 1 to rise steadily and meet the liquid injection requirements.

[0074] According to some embodiments of the present invention, in the first pressurization stage, the opening degree of the intake solenoid valve 413 is no greater than one-fifth of its maximum opening degree. The first pressurization stage is the initial stage in which gas is injected into the outer casing 1 to gradually increase the pressure inside the casing 1. By controlling the upper limit of the opening degree of the intake solenoid valve 413 in the first pressurization stage, the intake rate in the first pressurization stage can be reduced. This avoids the risk of active materials falling off the battery cell of the battery 10 due to an excessively fast intake rate in the initial stage of pressurization, thereby improving the reliability of injecting electrolyte into the battery 10.

[0075] According to some embodiments of the present invention, in the second pressurization stage, the opening degree of the intake solenoid valve 413 gradually increases until the opening degree of the intake solenoid valve 413 reaches its maximum. This ensures sufficient intake rate in both the second pressurization stage and the pressure stabilization stage, allowing the pressure inside the outer casing 1 to rise steadily and meet the liquid injection requirements.

[0076] According to some embodiments of the present invention, during the pressure stabilization phase, the pressure inside the outer casing 1 remains constant. That is, during the positive pressure phase, the pressure inside the outer casing 1 is gradually increased to a certain value, and then maintained for a period of time (i.e., the duration of the pressure stabilization phase), so that the electrolyte in the injection cup 21 can enter the battery 10 under the push of high pressure. Further, the battery injection method also includes: obtaining the pressure value inside the outer casing 1, the pressure of the first pressure boosting phase being the first pressure, the pressure of the pressure stabilization phase being the second pressure, and when the first pressure reaches a first pressure threshold, entering the second pressure boosting phase, wherein the first pressure threshold and the second pressure satisfy P1 / P2≤0.4.

[0077] In other words, in the first boost stage, when the pressure gradually rises to 40% of the second pressure, the second boost stage begins. By controlling the pressure in the first boost stage, damage to the battery cell can be avoided due to excessive pressure or too fast liquid injection rate, thereby improving the reliability of liquid injection into the battery 10.

[0078] According to some embodiments of the present invention, the air intake rate in the first boosting stage is no greater than 5 kPa / s. Therefore, the air intake rate in the first boosting stage can be controlled within a small range, thereby reducing the liquid injection rate into the battery 10 during the first boosting stage, and thus avoiding damage to the cell caused by excessively fast liquid injection. The air intake rate in the first boosting stage can be 5 kPa / s, 4.8 kPa / s, 4.5 kPa / s, 4.2 kPa / s, 4 kPa / s, 3.8 kPa / s, or 3.5 kPa / s, etc., and no specific limitation is made here.

[0079] Specifically, the intake rate of the outer cover 1 is controlled by the intake solenoid valve 413. During the pressure stabilization stage, the intake solenoid valve 413 is at its maximum opening. During the first pressure boosting stage, the opening of the intake solenoid valve 413 is controlled to be no more than one-fifth of the maximum opening of the battery valve 10, so as to avoid the battery cell being damaged by the excessively fast intake rate during the first pressure boosting stage.

[0080] According to some embodiments of the present invention, during the first pressurization stage, the liquid level drop rate in the injection cup 21 is no greater than 15 mm / s. It is understood that the faster the liquid level drop rate in the injection cup 21, the faster the electrolyte level in the electrolyte-filled battery 10, and the higher the risk of impact damage to the battery cell. Therefore, by controlling the liquid level drop rate in the injection cup to no more than 15 mm / s during the first pressurization stage, damage to the battery cell due to excessively fast injection speed can be avoided. The liquid level drop rate in the injection cup during the first pressurization stage can be 15 mm / s, 14 mm / s, 13 mm / s, 12 mm / s, 11 mm / s, 10 mm / s, etc., and no specific limitation is made here.

[0081] In some embodiments, after the voltage stabilization phase, when there is no electrolyte in the injection cup 21, the electrolyte injection is complete; when there is electrolyte in the injection cup 21, the system enters a negative pressure phase and returns to a positive pressure phase after the negative pressure phase ends. That is, after the voltage stabilization phase ends (i.e., the electrolyte level in the injection cup 21 no longer drops), when there is electrolyte in the injection cup 21, it indicates that there is gas in the battery 10, and electrolyte injection cannot continue. Therefore, by entering the negative pressure phase, the gas in the battery 10 is extracted, and then the first pressure boosting phase, the second pressure boosting phase, and the voltage stabilization phase can be performed again to pressurize the outer casing 1 and push the electrolyte in the injection cup 21 into the battery 10 again. The above process is repeated until the electrolyte in the injection cup 21 is completely injected into the battery 10, thereby completing the battery electrolyte injection process.

[0082] In some embodiments, during the pressure stabilization phase, the rate of liquid level decrease in the injection cup 21 is acquired. When the rate of liquid level decrease in the injection cup 21 is lower than a first rate threshold, a negative pressure phase is entered. During the negative pressure phase, the rate of liquid level increase in the injection cup 21 is acquired. When the rate of liquid level increase in the injection cup 21 is lower than a second rate threshold, a positive pressure phase is entered. Specifically, when the rate of liquid level decrease in the injection cup 21 is lower than the first rate threshold, it indicates that the injection rate into the battery 10 is too slow due to gas inside the battery 10. Switching to the negative pressure phase allows the gas inside the battery 10 to be extracted for subsequent re-injection. When the rate of liquid level increase in the injection cup 21 is lower than the first rate threshold, it indicates that the gas inside the battery 10 has been largely extracted, and the electrolyte can be injected into the battery 10 again by switching to the positive pressure phase. Therefore, by judging the rate of change of the liquid level in the injection cup 21 and controlling the switching between the positive and negative pressure phases, the injection efficiency can be improved.

[0083] In some embodiments, the first rate threshold and the second rate threshold are not greater than 2 mm / min.

[0084] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a 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 invention according to the specific circumstances.

[0085] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0086] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery electrolyte filling device, characterized in that, include: Outer cover; The electrolyte injection assembly is located inside the outer cover and includes an electrolyte injection cup. The electrolyte injection cup is used to store electrolyte and is suitable for connection with the battery. The electrolyte injection cup is a light-transmitting component. A liquid level detection component includes an image receiver and a light-emitting unit, the image receiver and the light-emitting unit being located on opposite sides of the injection cup along a first direction, the light-emitting unit being used to emit light toward the injection cup along the first direction, the first direction being perpendicular to the vertical direction; A pressure regulating component is connected to the outer casing and is used to regulate the pressure inside the outer casing; A control component is used to receive images acquired by the image receiver and control the air pressure regulating component to adjust the pressure inside the outer casing.

2. The battery electrolyte filling device according to claim 1, characterized in that, The light-emitting unit is a flash lamp; and / or, both the image receiver and the light-emitting unit are fixed to the outer cover.

3. The battery electrolyte filling device according to claim 1, characterized in that, The liquid injection assembly includes a battery holder for holding the battery, a liquid injection cup detachably disposed on the upper side of the battery holder, and the battery connected to the lower side of the liquid injection cup.

4. The battery electrolyte filling device according to claim 1, characterized in that, The air pressure regulating assembly includes an air intake device, an air pressure detection device, and a vacuum negative pressure device. The air intake device and the vacuum negative pressure device are both connected to the interior of the outer cover. The air intake device is used to supply gas into the outer cover, and the vacuum negative pressure device is used to discharge gas from the outer cover. The air pressure detection device is located inside the outer cover. The air intake device, the air pressure detection device, and the vacuum negative pressure device are all electrically connected to the control unit.

5. The battery electrolyte filling device according to claim 4, characterized in that, The air pressure detection device is located at the top of the outer cover, while the connection points of the air intake device and the vacuum negative pressure device with the outer cover are both located at the bottom of the outer cover.

6. The battery electrolyte filling device according to claim 4, characterized in that, The air intake device includes an air tank, an air intake pipe, and an air intake solenoid valve. The air tank is connected to the inside of the outer casing through the air intake pipe. The air intake solenoid valve is located on the air intake pipe and is used to control the flow rate of the air intake pipe. The vacuum negative pressure device includes a vacuum pump, an exhaust pipe, and an exhaust solenoid valve. The vacuum pump is connected to the inside of the outer casing through the exhaust pipe. The exhaust solenoid valve is located on the exhaust pipe and is used to control the flow rate of the exhaust pipe. Both the air intake solenoid valve and the exhaust solenoid valve are electrically connected to the control unit.

7. A battery electrolyte filling method, characterized in that, include: Connect the battery to the filling cup and place it inside the outer casing; Perform the liquid injection procedure; Detect whether there are solid particles in the electrolyte inside the injection cup; Adjust the rate of change of air pressure inside the outer cover and the rate of change of liquid level inside the injection cup during the injection process, depending on whether there are solid particles in the electrolyte inside the injection cup. The injection is complete when there is no electrolyte in the injection cup.

8. The battery electrolyte injection method according to claim 7, characterized in that, The outer casing is connected to an air inlet pipe and an air outlet pipe. The liquid injection process includes alternating positive pressure and negative pressure stages. During the positive pressure stage, gas is supplied to the outer casing through the air inlet pipe, and during the negative pressure stage, gas is discharged from the outer casing through the air outlet pipe. The air inlet pipe is equipped with an air inlet solenoid valve, and the air outlet pipe is equipped with an air outlet solenoid valve. Adjusting the rate of change of air pressure inside the outer casing during the liquid injection process includes controlling the opening degree of the air inlet solenoid valve and the air outlet solenoid valve.

9. The battery electrolyte injection method according to claim 8, characterized in that, When solid particles are detected in the electrolyte of the injection cup, the opening degree of the intake solenoid valve or the exhaust solenoid valve is reduced. When no solid particles are detected in the electrolyte of the injection cup, the intake solenoid valve and the exhaust solenoid valve are controlled to remain at their current opening positions.

10. The battery electrolyte injection method according to claim 9, characterized in that, The opening degree of the intake solenoid valve and the exhaust solenoid valve shall not decrease by more than 10% in a single operation.

11. The battery electrolyte injection method according to claim 9, characterized in that, When solid particles are detected in the electrolyte of the injection cup, the opening degree of the intake solenoid valve and the exhaust solenoid valve is reduced according to the distribution density of the solid particles in the electrolyte.

12. The battery electrolyte injection method according to claim 8, characterized in that, The positive pressure stage includes a first pressure boosting stage, a second pressure boosting stage, and a pressure stabilizing stage performed sequentially. During the first pressure boosting stage, the second pressure boosting stage, and the pressure stabilizing stage, the opening degree of the intake solenoid valve increases sequentially.

13. The battery electrolyte injection method according to claim 12, characterized in that, During the first pressurization phase, the opening degree of the intake solenoid valve is no greater than one-fifth of the maximum opening degree of the intake solenoid valve; and / or, during the second pressurization phase, the opening degree of the intake solenoid valve gradually increases until the opening degree of the intake solenoid valve reaches the maximum opening degree.

14. The battery electrolyte injection method according to claim 12, characterized in that, During the voltage stabilization phase, the pressure inside the outer casing remains constant, and the battery electrolyte injection method further includes: The pressure value inside the outer casing is obtained. The pressure in the first pressurization stage is the first pressure, and the pressure in the pressure stabilization stage is the second pressure. When the first pressure reaches the first pressure threshold, the second pressurization stage is entered. The first pressure threshold and the second pressure satisfy P1 / P2≥0.

4.

15. The battery electrolyte injection method according to claim 12, characterized in that, The air intake rate during the first pressurization stage is no greater than 5 kPa / s; and / or, during the first pressurization stage, the liquid level drop rate in the injection cup is no greater than 15 mm / s.

Images