CN115566377A

CN115566377A - Liquid injection method and liquid injection equipment

Info

Publication number: CN115566377A
Application number: CN202211553096.5A
Authority: CN
Inventors: 徐领松; 刘佳奇
Original assignee: China Lithium Battery Technology Co Ltd
Current assignee: China Lithium Battery Technology Co Ltd
Priority date: 2022-12-06
Filing date: 2022-12-06
Publication date: 2023-01-03

Abstract

The application provides a liquid injection method and liquid injection equipment, wherein the liquid injection method comprises the following steps: injecting electrolyte into the battery through a first injection port at a first end in the length direction of the battery; vacuumizing the battery at a second liquid injection port positioned at a second end in the length direction of the battery; the first end and the second end are oppositely arranged; before vacuumizing is stopped, the first liquid injection port is blocked; and after the pressure in the battery returns to the normal pressure, the second liquid injection port is blocked. In the technical scheme, when liquid is injected, one liquid injection port injects liquid into the battery, and the other liquid injection port conducts vacuum pumping outwards, so that the efficiency of injecting liquid into the battery is improved, and the liquid injection effect is improved.

Description

Liquid injection method and liquid injection equipment

Technical Field

The application relates to the technical field of batteries, in particular to a liquid injection method and liquid injection equipment.

Background

In the process of preparing the battery, electrolyte needs to be injected into the battery, the current liquid injection method is to inject liquid into a liquid injection port of the battery through liquid injection equipment, in the liquid injection process, the liquid injection port needs to be continuously vacuumized and injected with liquid, and the overall liquid injection efficiency is low.

Disclosure of Invention

The application provides a liquid injection method and liquid injection equipment, which are used for improving the liquid injection effect of a battery.

In a first aspect, a liquid injection method is provided, which includes the following steps:

injecting electrolyte into the battery through a first injection port at a first end in the length direction of the battery;

vacuumizing the battery at a second liquid injection port positioned at a second end in the length direction of the battery; the first end and the second end are oppositely arranged;

before vacuumizing is stopped, the first liquid injection port is blocked;

and after the pressure in the battery returns to the normal pressure, the second liquid injection port is blocked.

In the technical scheme, when liquid is injected, one liquid injection port injects liquid into the battery, and the other liquid injection port injects liquid outwards to perform vacuumizing, so that the efficiency of injecting liquid into the battery is improved, and the liquid injection effect is improved.

In a second aspect, there is provided a liquid injection apparatus, comprising:

the electrolyte injection cup is used for caching electrolyte and is provided with a liquid outlet which is in sealed communication with the first electrolyte injection port; a plugging rod for plugging the first liquid injection port is arranged in the liquid injection cup body;

and the vacuumizing device comprises a vacuum pipeline communicated with the second liquid injection port and a vacuum pump communicated with the vacuum pipeline.

In the technical scheme, when liquid is injected, one liquid injection port injects liquid into the battery, and the other liquid injection port conducts vacuum pumping outwards, so that the efficiency of injecting liquid into the battery is improved, and the liquid injection effect is improved.

Drawings

Fig. 1 is a schematic structural diagram of a battery corresponding to a liquid injection method provided in an embodiment of the present application;

fig. 2 is a flowchart of a liquid injection method provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of a liquid injection device provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of a vacuum duct provided in an embodiment of the present application.

Detailed Description

The present application is described in further detail below with reference to the figures and examples. The features and advantages of the present application will become more apparent from the description.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

In addition, the technical features related to the different embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

To facilitate understanding of the liquid injection method provided in the embodiment of the present application, an application scenario thereof is first described. The liquid injection method provided by the embodiment of the application is used for injecting liquid into a battery, the liquid injection is performed in a liquid injection port in the current liquid injection mode, liquid injection and air extraction are required at intervals, and the overall liquid injection efficiency is low. Therefore, the embodiment of the application provides a liquid injection method for improving the liquid injection efficiency. The following detailed description is made with reference to the specific drawings and examples.

Referring to fig. 1, a battery 100 corresponding to a liquid injection method provided by an embodiment of the present application is shown in fig. 1. The battery 100 is a rectangular parallelepiped battery 100, and the terminal is provided on a large surface of the battery 100, which is the largest surface area of the outer surfaces of the battery 100. The battery 100 has two liquid pouring ports provided to face each other. The first end 110 and the second end 120 of the battery 100 are defined for convenience of description, and the first end 110 and the second end 120 are both ends of the battery 100 in the length direction. The pouring outlet at the first end 110 is a first pouring outlet 200, and the pouring outlet at the second end 120 is a second pouring outlet 300.

Referring to fig. 2, fig. 2 shows a flowchart of a liquid injection method provided in an embodiment of the present application. The liquid injection method provided by the embodiment of the application comprises the following steps:

step 001: injecting electrolyte into the battery through a first injection port positioned at a first end of the battery in the length direction;

specifically, referring to FIG. 3, in the case of pouring liquid, the liquid is poured into the first pouring outlet 200 through the pouring cup 10. Illustratively, the liquid pouring cup 10 includes a cup body 11, the cup body 11 is used for storing electrolyte, and both ends of the cup body 11 are open, wherein the opening of the first end 110 of the cup body 11 is a liquid pouring hole, and during liquid pouring, the cup body is inserted into the first liquid pouring port 200, so that the electrolyte in the cup body 11 can be poured into the battery 100. The opening at second end 120 of cup 11 is an injection port for injecting electrolyte into cup 11.

In particular, to facilitate filling, the first end 110 of the cup 11 has an inverted conical configuration such that the first end 110 of the cup 11 gradually contracts to facilitate the flow of electrolyte into the first filling opening 200. The main body shape of the cup body 11 is a cylindrical tubular structure, but the main body shape of the cup body 11 is not limited to the cylindrical tubular structure, and may be other shapes such as a rectangular parallelepiped shape or other shapes, and is not limited herein.

When the electrolyte is injected into the battery 100, the electrolyte stored in the cup 11 can flow into the first injection port 200 from the cup 11 by gravity. Of course, in addition to relying on the gravity of the electrolyte, other methods may be used, such as pumping the electrolyte into the battery 100 by a pump, and the electrolyte may be injected into the battery 100.

It should be understood that the liquid filling cup 10 provided in the embodiments of the present application may be made of metal or other material with sufficient strength, and the volume of the liquid filling cup can ensure that all the electrolyte required by the battery 100 can be stored.

The pour cup 10 can also include a stopper rod 12, and the stopper rod 12 is located within the cup body 11 of the pour cup 10 and is movable relative to the cup body 11. When the stopper rod in the liquid pouring cup 10 is pressed down and the electrolyte is poured into the cup body 11, the first liquid pouring port 200 is sealed and the electrolyte completely flows into the cup body 11 of the liquid pouring cup 10.

Step 002: vacuumizing the battery at a second liquid injection port positioned at a second end in the length direction of the battery;

specifically, with continued reference to fig. 1, first end 110 and second end 120 of battery 100 are oppositely disposed, e.g., first end 110 and second end 120 are opposite ends of battery 100 along its length. Thereby enabling a longer distance between the priming position and the evacuation position.

When the battery 100 is evacuated, the evacuation may be performed through a pipe. Such as by vacuum line 20. Referring to fig. 4 together, fig. 4 shows the structure of the vacuum tube 20, the vacuum tube 20 is a tubular structure, one end of the vacuum tube 20 is connected to the second liquid injection port 300, and when the vacuum tube is connected, the two are sealed, so as to improve the vacuum effect. The other end of the vacuum pipe 20 is connected to a vacuum pump. At the time of vacuum pumping, air inside battery 100 is pumped by a vacuum pump.

Referring to fig. 3 and 4 together, when the vacuum tube 20 is connected to the second liquid injection port 300, and when the vacuum tube 20 is connected to the second liquid injection port 300, a sealing nozzle 30 is disposed at one end of the vacuum tube 20, and the sealing nozzle 30 is connected to the second liquid injection port 300 in a sealing manner, so as to ensure the sealing effect during vacuum pumping.

Specifically, when the battery 100 is evacuated, the electrolyte in the electrolyte injection cup 10 can be driven into the battery 100 by the negative pressure generated in the battery 100 during evacuation, thereby improving the electrolyte injection effect.

Referring to fig. 1 and 3 together, when the second liquid inlet 300 at the second end 120 of the battery 100 in the longitudinal direction is used to evacuate the battery 100, the battery 100 is evacuated at a pressure of < -90 KPa. That is, the pressure of the vacuum pipe 20 during the vacuum-pumping is less than-90 KPa, and the pressure may be, for example, different vacuum-pumping pressures of-90 KPa, -80KPa, -60KPa, -50KPa, etc. Therefore, the phenomenon that electrolyte cannot fully soak the electric core body due to overlarge pressure during vacuum pumping is avoided. It should be understood that the minimum pressure to draw a vacuum should be sufficient to ensure that the driving electrolyte flows within the cell 100.

When the battery 100 is filled with liquid and evacuated, the liquid filling position and the evacuation position are located at two opposite sides of the battery 100 (the first end 110 and the second end 120 of the battery 100), so that the distance between the two positions is large, air in the battery 100 can be conveniently and quickly extracted, and the evacuated negative pressure can drive the electrolyte to travel for a longer distance (from the first end 110 to the second end 120 of the battery 100), as shown in an exemplary direction of a straight line with an arrow in fig. 3, so that the liquid filling speed is increased.

As an alternative, the injection position is located diagonally to the evacuation position. Illustratively, the first liquid injection port 200 and the second liquid injection port 300 are arranged diagonally, so that the distance between the vacuumized position and the liquid injection position is larger during liquid injection, and the liquid injection speed is further increased.

During the specific evacuation, two different evacuation manners can be adopted, which are described below.

The first method is as follows: when the battery 100 is evacuated, the carried-out electrolyte flows into the liquid pouring cup 10 again.

Specifically, in this embodiment, one end of the vacuum pipe 20 is directly connected to the second liquid inlet 300, and no structure for blocking the electrolyte is provided therebetween. During the evacuation of the vacuum pipe 20, the electrolyte is inevitably drawn into the vacuum pipe 20.

One end of the vacuum pipeline 20 can be connected with a buffer pool, the electrolyte carried out when the battery 100 is vacuumized can be stored in the buffer pool, then the buffer pool is communicated with the liquid injection cup 10 through a pipeline, and the electrolyte in the buffer pool can be led into the liquid injection cup 10 to be used for being flushed into the battery 100 again.

Of course, besides the above scheme, the vacuum pipeline 20 can be communicated with the liquid injection cup 10 through a pipeline, and the electrolyte carried out by vacuumizing can directly flow back into the liquid injection cup 10. Illustratively, when the vacuum pipeline 20 is connected with a vacuum pump, the air outlet of the vacuum pump is communicated with the liquid injection cup 10 through a pipeline.

The second method comprises the following steps: during evacuation, air in battery 100 is drawn out, and the outflow of electrolyte in battery 100 is prevented.

Specifically, in the above embodiment, the vacuum pipe 20 is provided with a structure for blocking the electrolyte at a position connected to the second inlet 300.

With continued reference to fig. 4, air from the battery 100 is drawn through the vacuuming duct 20 connected to the second liquid injection port 300; the outflow of the electrolyte is prevented by the air-permeable and waterproof layer 40 provided between the second pouring port 300 and the vacuum pipe 20.

The structure corresponding to this mode will be described in detail below with reference to fig. 3 and 4 of the drawings. Fig. 4 shows a schematic view of the vacuum line 20. When the vacuum pipeline 20 is specifically arranged, one end of the vacuum pipeline 20, which is communicated with the second liquid injection port 300, is provided with a layer of breathable waterproof layer 40. When the air-permeable and waterproof layer 40 is fixed, the air-permeable and waterproof layer 40 may be interposed between the sealing nozzle 30 and the vacuum duct 20 to ensure stability of the air-permeable and waterproof layer 40.

The air-permeable and water-proof layer 40 is a structure that allows air to pass through but prevents liquid from passing through. For example, the air-permeable and water-proof layer 40 has a certain microscopic holes, so that the air-permeable layer can effectively block the liquid from permeating. When specifically configured, the air-permeable and water-proof layer 40 may be a PTFE microporous film (polytetrafluoroethylene), a PU breathable film (polyurethane), a PVDF microporous film (polyvinylidene fluoride), etc., or a composite film thereof (e.g., a PU/PVDF mixed film, etc.).

In addition, when the air-permeable and waterproof layer 40 is provided, metal meshes 50 may be further included, which are interposed between opposite sides of the air-permeable and waterproof layer 40. That is, the air-permeable and water-proof layer 40 is disposed between the two metal nets 50. The two metal nets 50 and the air-permeable and water-proof layer 40 form a sandwich-like structure. The metal mesh 50 can enhance the structural strength of the breathable waterproof layer 40, so that the breathable waterproof layer 40 cannot be adsorbed to be separated from the arranged position during vacuum pumping, and the blocking effect on the electrolyte is guaranteed. The metal mesh 50 may be made of different materials such as copper wires, aluminum wires, steel wires, etc., and only needs to have sufficient supporting strength. As an alternative, the above-mentioned metal net 50 may be a high-mesh metal net 50. For example, the mesh number of the metal mesh 50 is greater than or equal to 200 mesh, and the mesh number of the metal mesh 50 may be 200 mesh, 300 mesh, 400 mesh, 500 mesh, or other different mesh numbers.

When the structure is adopted, the air-permeable and waterproof layer 40 has certain mechanical strength, and the metal mesh 50 is fixed on two sides of the air-permeable and waterproof layer 40, so that the mechanical strength is further enhanced.

Step 003: before the vacuumizing is stopped, the first liquid injection port 200 is blocked;

specifically, to prevent the electrolyte from flowing back into the liquid injection cup 10 immediately after the completion of the liquid injection, the first liquid injection port 200 is closed before the evacuation is stopped.

Referring to FIG. 3, when the first pouring outlet 200 is closed, the first pouring outlet 200 is closed by the closing lever 12 inside the pouring cup 10.

Specifically, the end of the plugging rod 12 for insertion into the first pouring outlet 200 matches the shape of the first pouring outlet 200. When the stopper rod 12 is inserted into the first pouring outlet 200, the end of the stopper rod 12 can be sealingly connected to the first pouring outlet 200. The plugging rod 12 is, for example, a rod made of an elastic material, and can plug the first liquid inlet 200 by deforming when inserted into the first liquid inlet 200. For example, the plugging rod 12 is a rubber rod or a plugging rod 12 made of other materials.

The plugging rod 12 can be manually inserted into the pouring cup 10 to plug the first pouring outlet 200. Alternatively, and illustratively, the pour cup 10 is provided with a drive mechanism remote from the second end 120 that drives the stem 12 within the cup body 11. If the driving mechanism is a driving air cylinder or a driving hydraulic cylinder, a piston rod of the driving air cylinder or the driving hydraulic cylinder is fixedly connected with the plugging rod 12. In the process of extending and retracting the piston rod, the plugging rod 12 is driven to move so as to plug the first liquid injection port 200.

Step 004: and after the pressure in the battery returns to the normal pressure, the second liquid injection port is blocked.

Specifically, after the filling is completed, the vacuum pipe 20 is removed, and the second filling port 300 is closed when the pressure inside the battery 100 returns to the normal pressure. It should be understood that the above-mentioned normal pressure is referred to as an atmospheric pressure, or approximately an atmospheric pressure, and it is only necessary to ensure that the pressure inside and outside the case of the battery 100 is consistent.

The traditional high-pressure isobaric injection of the single-hole battery at present needs to design a larger isobaric cavity because of the gradual increase of the volume of the battery at present, so that high equipment cost is brought, a large amount of energy consumption can be wasted by the large cavity in the process of vacuumizing and pressurizing, and the cavity with the weight of the top ton and the high-pressure condition of more than 500KPa also have certain potential safety hazards in production. The accumulation of tens of cavities also puts high demands on the bearing capacity of the plant. And adopt the differential pressure to annotate the liquid mode, annotate liquid efficiency very low, need more annotate the liquid station when realizing the same production efficiency, equipment purchasing cost also can increase. Therefore, the liquid injection method provided by the embodiment of the application adopts the liquid injection process of the double-liquid-injection-hole metal-shell battery, and a high positive pressure cavity and an equal pressure cavity are not needed, so that the energy consumption cost and the equipment cost are greatly reduced, and the potential safety hazard of production is eliminated. In addition, the liquid is injected into the battery through one liquid injection port, the other liquid injection port is vacuumized outwards, and the electrolyte directly enters the battery at one time, so that the liquid injection efficiency of the battery is improved, the liquid injection effect is improved, and the high-efficiency liquid injection under a simple process is realized.

With continuing reference to fig. 3 and fig. 3, an embodiment of the present application further provides a liquid injection apparatus, including: a liquid injection cup 10 body and a vacuum pumping device. The liquid filling cup 10 is used for filling the battery 100, and the vacuum extractor is used for extracting air in the battery 100. The structure of the liquid pouring cup 10 and the vacuum extractor will be described in detail below with reference to the accompanying drawings.

The liquid injection cup 10 is used for caching electrolyte, and a liquid outlet which is used for being in sealed communication with the first liquid injection port 200 is formed in the liquid injection cup 10; the liquid pouring cup 10 is provided with a stopper rod 12 for stopping the first liquid pouring port 200. Illustratively, the pour cup 10 includes a cup body 11 and a stopper rod 12. The cup 11 is used for buffering electrolyte, and two ends of the cup 11 are open, wherein the opening at the first end 110 of the cup 11 is a filling hole, and during filling, the filling hole is inserted into the first filling port 200, so that the electrolyte in the cup 11 can be filled into the battery 100. The opening at second end 120 of cup 11 is an injection port for injecting electrolyte into cup 11.

When the electrolyte is poured into the battery 100, the electrolyte stored in the cup 11 can flow into the first pouring port 200 from the cup 11 by gravity. Of course, in addition to relying on the gravity of the electrolyte, other methods may be used, such as pumping the electrolyte into the battery 100 by a pump, and the electrolyte may be injected into the battery 100.

The plugging rod 12 is positioned in the cup body 11 of the liquid pouring cup 10 and can move relative to the cup body 11. When the first pouring outlet 200 is closed, the first pouring outlet 200 is closed by the closing pin 12 in the pouring cup 10.

The evacuation device is used to evacuate the battery 100. The vacuum-pumping device comprises a vacuum pipeline 20, the vacuum pipeline 20 is used for communicating with the second liquid injection port 300, and a vacuum pump is communicated with the vacuum pipeline 20. In the specific installation, one end of the vacuum pipe 20 is connected to the second liquid inlet 300, and when the vacuum pipe is connected, the connection therebetween is sealed, so as to improve the vacuum-pumping effect. The other end of the vacuum pipe 20 is connected to a vacuum pump. At the time of evacuation, air in battery 100 is drawn by a vacuum pump.

When the vacuum pipeline 20 is connected to the second liquid injection port 300, and when the vacuum pipeline 20 is connected to the second liquid injection port 300, a sealing nozzle 30 is disposed at one end of the vacuum pipeline 20, for example, the vacuum pumping device further comprises a sealing nozzle 30 which is away from one end of the vacuum pump from the vacuum pipeline 20, and the sealing nozzle 30 is used for being in sealing communication with the second liquid injection port 300, so as to ensure the sealing effect during vacuum pumping.

When the battery 100 is vacuumized, the electrolyte in the electrolyte injection cup 10 can be driven into the battery 100 by the negative pressure formed in the battery 100 during vacuuming, so that the electrolyte injection effect is improved.

When the battery 100 is evacuated through the second liquid inlet 300 located at the second end 120 of the battery 100 in the longitudinal direction, the battery 100 is evacuated at a pressure of < -90 KPa. That is, the pressure of the vacuum pipe 20 during vacuum pumping is less than-90 KPa, and illustratively, the pressure may be different vacuum pumping pressures such as-90 KPa, -80KPa, -60KPa, -50KPa and the like. Therefore, the phenomenon that the electrolyte cannot fully infiltrate the electric core body due to overlarge pressure during vacuum pumping is avoided. It should be understood that a minimum pressure to draw a vacuum should be able to ensure that the driving electrolyte flows within the cell 100.

A structure for blocking the electrolyte is provided at a position where the vacuum pipe 20 is connected to the second injection port 300. Illustratively, air in the battery 100 is drawn through the vacuuming pipe 20 connected to the second liquid injection port 300; the vacuum pumping device further comprises a breathable waterproof layer 40 arranged at one end of the vacuum pipeline 20 far away from the vacuum pump. The air-permeable and waterproof layer 40 is located between the vacuum pipe 20 and the second pouring port 300, so that the outflow of the electrolyte can be prevented by the air-permeable and waterproof layer 40 provided between the second pouring port 300 and the vacuum pipe 20.

When the vacuum pipeline 20 is arranged, one end of the vacuum pipeline 20, which is communicated with the second liquid injection port 300, is provided with a layer of breathable waterproof layer 40. When the air-permeable and waterproof layer 40 is fixed, the air-permeable and waterproof layer 40 may be interposed between the sealing nozzle 30 and the vacuum duct 20 to ensure stability of the air-permeable and waterproof layer 40.

The air-permeable and water-proof layer 40 is a structure that allows air to pass through but prevents liquid from passing through. Illustratively, the air-permeable and water-proof layer 40 has microscopic holes, so as to effectively block liquid from permeating while being air-permeable. In a specific arrangement, the air-permeable and waterproof layer 40 may be a PTFE microporous film (polytetrafluoroethylene), a PU breathable film (polyurethane), a PVDF microporous film (polyvinylidene fluoride), or the like, or a composite film thereof (e.g., a PU/PVDF mixed film, or the like).

In addition, when the air-permeable and waterproof layer 40 is provided, the vacuum-pumping device further includes metal meshes 50 interposed on opposite sides of the air-permeable and waterproof layer 40. That is, the air-permeable and water-proof layer 40 is disposed between the two metal nets 50. The two metal meshes 50 and the air-permeable and water-proof layer 40 form a sandwich-like structure. The metal mesh 50 can enhance the structural strength of the breathable waterproof layer 40, so that the breathable waterproof layer 40 cannot be adsorbed to be separated from the arranged position during vacuum pumping, and the blocking effect on the electrolyte is guaranteed. The metal mesh 50 may be made of different materials such as copper wires, aluminum wires, steel wires, etc., and only needs to have sufficient supporting strength. As an alternative, the above-mentioned metal net 50 may be a high-mesh metal net 50. For example, the mesh number of the metal mesh 50 is greater than or equal to 200 mesh, and the mesh number of the metal mesh 50 may be 200 mesh, 300 mesh, 400 mesh, 500 mesh, or other different mesh numbers.

When the structure is adopted, the base fabric ensures certain mechanical strength, and the metal mesh 50 is fixed on two sides of the breathable waterproof layer 40, so that the mechanical strength is further enhanced.

In particular use, reference is made to the description relating to the method described above. The notes liquid equipment that this application embodiment provided is through adopting when annotating the liquid, annotates the liquid mouth and annotate the liquid in to battery 100 for one, annotates the liquid mouth and outwards carry out the evacuation for one to improve the efficiency of annotating the liquid to battery 100, improved and annotated the liquid effect.

In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on operational states of the present application, and are only used for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application.

In the description of the present application, it is to be noted that the terms "mounted," "connected," and "connected" are to be construed broadly unless otherwise explicitly stated or limited. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The present application has been described above in connection with preferred embodiments, which are intended to be exemplary only and illustrative only. On the basis of the above, the present application can be subjected to various substitutions and modifications, which are all within the scope of protection of the present application.

Claims

1. The liquid injection method is characterized by comprising the following steps:

before vacuumizing is stopped, the first liquid injection port is blocked;

2. The electrolyte injection method according to claim 1, wherein the electrolyte is injected into the battery through the first injection port located at the first end of the battery in the length direction; the method specifically comprises the following steps:

and injecting electrolyte into the first liquid injection port through the liquid injection cup body.

3. The liquid injection method according to claim 2, wherein the first liquid injection port is sealed before the evacuation is stopped; the method specifically comprises the following steps:

and the first liquid injection port is blocked by a blocking rod in the liquid injection cup body.

4. The electrolyte injection method according to claim 3, wherein the battery is evacuated through the second electrolyte injection port located at the second end in the longitudinal direction of the battery; the method specifically comprises the following steps:

drawing air inside the battery and preventing an outflow of electrolyte inside the battery.

5. The liquid injection method according to claim 4, wherein air in the battery is extracted and outflow of the electrolyte in the battery is prevented; the method specifically comprises the following steps:

extracting air of the battery through a vacuumizing pipeline connected to the second liquid injection port;

and the outflow of the electrolyte is prevented by a breathable waterproof layer arranged between the second liquid injection port and the vacuum pipeline.

6. The electrolyte injection method according to claim 5, wherein the battery is evacuated through the second electrolyte injection port located at the second end in the longitudinal direction of the battery; the method comprises the following specific steps:

when the battery is vacuumized, the carried electrolyte flows into the liquid injection cup again.

7. The electrolyte injection method according to claim 5, wherein when the battery is evacuated through the second electrolyte injection port located at the second end in the longitudinal direction of the battery, the battery is evacuated at a pressure of < -90 KPa.

8. A priming apparatus, comprising:

9. The liquid injection device according to claim 8, wherein the vacuum pumping device further comprises a gas-permeable and waterproof layer disposed at an end of the vacuum pipeline far from the vacuum pump.

10. The liquid injection device according to claim 9, wherein the vacuum pumping device further comprises metal meshes clamped on two opposite sides of the air-permeable and waterproof layer.

11. The liquid injection device according to claim 10, wherein the vacuum pumping device further comprises a sealing nozzle at an end of the vacuum pipeline away from the vacuum pump; the sealing nozzle is used for being communicated with the second liquid injection port in a sealing mode.