Liquid injection and gas supply system and control method

Abstract

The invention discloses a liquid injection and gas supply system which comprises a standing tank, and the standing tank is connected with a gas supply part. The gas supply part comprises a first buffer tank and a second buffer tank, the first buffer tank is communicated with the standing tank, the second buffer tank is communicated with the standing tank, the first buffer tank and the second buffer tank are arranged in parallel and are both communicated with the standing tank through connecting pipelines, the second buffer tank is connected with a gas inlet pipeline, and the gas inlet pipeline is communicated with the standing tank. By the adoption of the double-buffer-tank design, the first buffer tank can supplement recycled gas to the standing tank, the second buffer tank can store the gas in the tank when equipment is idle for gas supplementation, the stored gas is supplemented to the standing cavity when the equipment is in use, the supply pressure of the main pipeline is reduced, the use efficiency of the main pipeline is improved, and the service life of the main pipeline is prolonged. And the beat efficiency of liquid injection standing is improved.

Description

Technical Field

[0001] The invention relates to a lithium battery liquid injection system, in particular to a liquid injection and gas supply system and a control method. Background Art

[0002] Lithium battery injection refers to the process of injecting electrolyte into the battery in the required amount through the reserved injection hole. Its main purpose is to form ion channels to ensure that there are enough lithium ions to migrate between the positive and negative electrodes during the charge and discharge process of the battery to achieve reversible circulation.

[0003] The process of lithium battery injection needs to be carried out in a standing tank, and the high-pressure nitrogen environment is improved by the standing tank. Therefore, in the process of production, nitrogen needs to be filled into the standing tank, and the nitrogen needs to be discharged during the battery injection process in the cavity of the standing tank, which will lead to a large amount of nitrogen consumption and high cost. At the same time, in the process of inflation, a large amount of nitrogen needs to be filled into the standing tank in a short time, and the main gas supply pipeline is often connected to multiple groups of injection equipment, which can easily lead to instantaneous insufficient gas supply, resulting in the air pressure in the standing tank for injection failing to meet the requirements, affecting the injection efficiency. Summary of the invention

[0004] The object of the present invention is to provide a liquid injection and gas supply system and a control method to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A liquid injection and air supply system comprises a stationary tank, wherein the stationary tank is connected to an air supply part;

[0007] The air supply part includes a first buffer tank connected to the stationary tank and a second buffer tank connected to the stationary tank. The first buffer tank and the second buffer tank are arranged in parallel and are both connected to the stationary tank through a connecting pipe. The second buffer tank is connected to an air intake pipe.

[0008] High-pressure nitrogen is filled into the second buffer tank through the air intake pipe to ensure that a certain amount of high-pressure nitrogen is stored in the second buffer tank. When nitrogen needs to be filled into the static tank, a large amount of nitrogen can be quickly increased to avoid insufficient nitrogen entering the air intake pipe, resulting in the static tank failing to reach the required pressure. At the same time, the nitrogen in the static tank is recycled and reused through the first buffer tank to reduce nitrogen loss.

[0009] As a further solution of the present invention: the stationary tank is provided with an air supply main pipe, the first buffer tank and the second buffer tank are both connected to the stationary tank through the air supply main pipe, and the air supply main pipe is provided with a first valve.

[0010] The first buffer tank and the second buffer tank are respectively connected to the gas supply main pipe, and nitrogen can be provided to the stationary tank through the gas supply main pipe.

[0011] As a further solution of the present invention: the first buffer tank is connected to the gas supply main pipe through a first gas supply branch pipe, and the second buffer tank is connected to the gas supply main pipe through a second gas supply branch pipe.

[0012] The first buffer tank and the second buffer tank are arranged in parallel and are connected to the gas supply main pipe through the first gas supply branch pipe and the second gas supply branch pipe respectively, so that the connection between the first buffer tank, the second buffer tank and the static tank can be controlled respectively.

[0013] As a further solution of the present invention: a second valve is provided on the first gas supply branch pipe, a third valve is provided on the second gas supply branch pipe, and the first valve, the second valve and the third valve are all remotely controlled electrical valves.

[0014] The communication between the first buffer tank, the second buffer tank and the static tank is controlled respectively by a plurality of valves, and all the valves are remotely controlled valves, which can improve the level of automated control.

[0015] As a further solution of the present invention: the first buffer tank and the second buffer tank are both provided with pressure gauges, and the first buffer tank is provided with a moisture detector and a drying and dehydration device.

[0016] The pressure of the first buffer tank and the second buffer tank is detected in time, and the moisture content of the gas in the first buffer tank is detected to ensure that the nitrogen entering the static tank meets the moisture content requirements.

[0017] As a further solution of the present invention: the standing tank is connected to an exhaust pipe, and the exhaust pipe is provided with a fourth valve and a vacuum pump.

[0018] The still tank can be evacuated by means of a vacuum pump.

[0019] A liquid injection gas supply control method comprises the following steps:

[0020] Step 1, connecting the static tank and the first buffer tank, and the gas enters the first buffer tank from the static tank;

[0021] Step 2: After the pressure of the static tank and the first buffer tank is balanced, disconnect the static tank from the first buffer tank;

[0022] Step 3, let the tank stand to exhaust and evacuate;

[0023] Step 4, connecting the static tank with the first buffer tank, inflating the static tank through the first buffer tank, and disconnecting the static tank from the first buffer tank when the pressure of the first buffer tank is the same as that of the static tank;

[0024] Step 5, connecting the static tank with the second buffer tank, and inflating the static tank through the second buffer tank until the set pressure;

[0025] Step 6: Place the tank in a static position to inject the battery liquid. After the injection is completed, proceed to step 1.

[0026] Recycle part of the gas in the static tank through the first buffer tank to reduce nitrogen consumption

[0027] As a further solution of the present invention: the first buffer tank is connected to the stationary tank by opening the first valve and the second valve, and the second buffer tank is connected to the stationary tank by opening the first valve and the third valve.

[0028] As a further solution of the present invention: in step 1, the gas entering the first buffer tank is tested for moisture; in step 3, the gas entering the static tank from the first buffer tank is tested for moisture, and a moisture content threshold is set. If the moisture content threshold is exceeded, the gas needs to be dried.

[0029] The recycled nitrogen is tested for moisture to avoid damage to the lithium battery injection due to excessive moisture.

[0030] As a further solution of the present invention: in the step 4, the high-pressure gas is first filled into the second buffer tank through the air intake pipe. When the second buffer tank is connected to the static tank, the second buffer tank fills the gas into the static tank, and at the same time, the air intake pipe replenishes the high-pressure gas to the second buffer tank.

[0031] The second buffer tank is used to instantly increase a sufficient amount of nitrogen for the static tank, ensuring that the static tank can reach the required static pressure in a short time.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The present application adopts a double buffer tank design. The first buffer tank can replenish the recovered gas to the static tank. The second buffer tank can store the gas in the tank when the equipment is idle and replenish gas. When it is used, the stored gas is replenished to the static cavity, which reduces the supply pressure of the main pipeline, improves the utilization efficiency of the main pipeline, and improves the rhythm efficiency of liquid injection and static.

[0034] 2. This application uses a moisture monitoring instrument to monitor the water content of the outlet pipeline to prevent gas with excessive moisture from entering the static system, thus avoiding the risk of liquid injection;

[0035] 3. This application uses pneumatic valves to control the gas of the entire system, which can control the flow rate and flow of the gas in the buffer tank, and condition the amount of gas in the recovery tank, so that the gas in the replenishment tank can be flexibly controlled. The entire system has a high degree of automation and can achieve flexible distribution of gases in various structures. When used in a network, it can increase the flexibility of the system and improve overall efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a front view of the gas supply system of this embodiment;

[0037] Figure 2 This is an axial side view of the air supply system of this embodiment;

[0038] Figure 3 This is a control flow chart of the gas supply system of this embodiment;

[0039] In the figure: 1-first buffer tank, 2-second buffer tank, 3-stationary tank, 4-gas supply main pipe, 5-first gas supply branch pipe, 6-second gas supply branch pipe, 7-first valve, 8-second valve, 9-third valve, 10-intake pipe, 11-exhaust pipe, 12-fourth valve, 13-vacuum pump. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] See also Figure 1-2 In an embodiment of the present invention, a liquid injection gas supply system includes a standing tank 3, the standing tank 3 is connected to an exhaust pipe 11, and the exhaust pipe 11 is provided with a fourth valve 12 and a vacuum pump 13, and the standing tank 3 can be evacuated by the vacuum pump 13.

[0042] The stationary tank 3 is connected to an air supply unit, which includes a first buffer tank 1 connected to the stationary tank 3 and a second buffer tank 2 connected to the stationary tank 3. The first buffer tank 1 and the second buffer tank 2 are arranged in parallel and are both connected to the stationary tank 3 through a connecting pipe. In this embodiment, an air supply main pipe 4 is provided on the stationary tank 3, and the first buffer tank 1 and the second buffer tank 2 are both connected to the stationary tank 3 through the air supply main pipe 4. The first buffer tank 1 is connected to the air supply main pipe 4 through a first air supply branch pipe 5, and the second buffer tank 2 is connected to the stationary tank 3 through a connecting pipe. The buffer tank 2 is connected to the gas supply main pipe 4 through the second gas supply branch pipe 6. The second buffer tank 2 is connected to the air intake pipe 10. High-pressure nitrogen is filled into the second buffer tank 2 through the air intake pipe 10 to ensure that a certain amount of high-pressure nitrogen is stored in the second buffer tank 2. When nitrogen needs to be filled into the still tank 3, a large amount of nitrogen can be quickly increased to avoid insufficient nitrogen entering the still tank 3 due to insufficient pressure in the air intake pipe 10. At the same time, the nitrogen in the still tank 3 is recycled and reused through the first buffer tank 1 to reduce the loss of nitrogen.

[0043] A first valve 7 is provided on the gas supply main pipe 4, a second valve 8 is provided on the first gas supply branch pipe 5, and a third valve 9 is provided on the second gas supply branch pipe 6. The first valve 7, the second valve 8, and the third valve 9 are all remotely controlled electrical valves. The connection between the first buffer tank 1, the second buffer tank 2 and the static tank is controlled respectively through multiple valves, and the valves are all remotely controlled valves, which can improve the level of automatic control.

[0044] The first buffer tank 1 and the second buffer tank 2 are both provided with pressure gauges. The first buffer tank 1 is provided with a moisture detector and a drying and dehydration device to timely detect the pressure of the first buffer tank 1 and the second buffer tank 2, and to perform moisture detection on the gas in the first buffer tank 1 to ensure that the nitrogen entering the standing tank 3 meets the moisture requirements.

[0045] See also Figure 3 , a liquid injection gas supply control method, comprising the following steps:

[0046] Step 1, the first buffer tank 1 is connected with the static tank 3 by opening the first valve 7 and the second valve 8, and the gas enters the first buffer tank 1 from the static tank 3, and the moisture content of the gas entering the first buffer tank 1 is detected, and a moisture content threshold is set. If the moisture content exceeds the threshold, the gas needs to be dried;

[0047] Step 2: After the pressure of the static tank 3 and the first buffer tank 1 is balanced, disconnect the static tank 3 from the first buffer tank 1;

[0048] Step 3, the standing tank 3 is exhausted and vacuumized;

[0049] Step 4, connecting the static tank 3 with the first buffer tank 1, inflating the static tank 3 through the first buffer tank 1, detecting the moisture of the gas entering the static tank 3 from the first buffer tank 1, and setting a moisture content threshold. If the moisture content threshold is exceeded, the gas needs to be dried. When the pressure of the first buffer tank 1 is the same as that of the static tank 3, disconnecting the static tank 3 from the first buffer tank 1;

[0050] First, high-pressure gas is charged into the second buffer tank 2 through the air intake pipe 10. When the second buffer tank 2 is connected to the stationary tank 3, the second buffer tank 2 charges the stationary tank 3 with gas. At the same time, the air intake pipe 10 replenishes high-pressure gas into the second buffer tank 2.

[0051] Step 5, the second buffer tank 2 is connected to the static tank 3 by opening the first valve 7 and the third valve 9, and the static tank 3 is inflated through the second buffer tank 2 until the set pressure;

[0052] Step 6: The static tank 3 is filled with liquid for the battery, and after the filling is completed, step 1 is executed.

[0053] Example 1

[0054] Step 1, the first buffer tank 1 is connected with the static tank 3 by opening the first valve 7 and the second valve 8, and the 700Kpa positive pressure nitrogen in the static chamber is discharged to the first buffer tank 1 through the first valve 7, and the moisture content of the gas entering the first buffer tank 1 is detected. In this embodiment, the moisture threshold is 100ppm, and the moisture content threshold is set at the same time. If the moisture content threshold is exceeded, the gas needs to be dried;

[0055] Step 2: After the pressure of the static tank 3 and the first buffer tank 1 is balanced, in this embodiment, when the pressure inside the first buffer tank 1 and the static tank is 300 KPa, the connection between the static tank 3 and the first buffer tank 1 is disconnected;

[0056] Step 3, the standing tank 3 is exhausted and vacuumized to -98Kpa;

[0057] Step 4, connecting the static tank 3 with the first buffer tank 1, inflating the static tank 3 through the first buffer tank 1, detecting the moisture of the gas entering the static tank 3 from the first buffer tank 1, and setting a moisture content threshold. If the moisture content threshold is exceeded, the gas needs to be dried. When the pressure of the first buffer tank 1 is the same as that of the static tank 3, disconnecting the static tank 3 from the first buffer tank 1;

[0058] First, high-pressure gas is charged into the second buffer tank 2 through the air intake pipe 10. When the second buffer tank 2 is connected to the stationary tank 3, the second buffer tank 2 charges the stationary tank 3 with gas, and at the same time, the air intake pipe 10 replenishes high-pressure gas into the second buffer tank 2.

[0059] Step 5, the second buffer tank 2 is connected to the static tank 3 by opening the first valve 7 and the third valve 9, and the static tank 3 is inflated through the second buffer tank 2 to reach the working required 700Kpa;

[0060] Step 6: The static tank 3 is filled with liquid for the battery, and after the filling is completed, step 1 is executed.

[0061] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0062] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A liquid injection and gas supply system, comprising a static tank (3), characterized in that: The stationary tank (3) is connected to a gas supply unit; The air supply unit comprises a first buffer tank (1) connected to the stationary tank (3) and a second buffer tank (2) connected to the stationary tank (3); the first buffer tank (1) and the second buffer tank (2) are arranged in parallel and both the first buffer tank (1) and the second buffer tank (2) are connected to the stationary tank (3) via a connecting pipe; the second buffer tank (2) is connected to an air intake pipe (10).

2. A liquid injection and gas supply system according to claim 1, characterized in that: The stationary tank (3) is provided with an air supply pipe (4), the first buffer tank (1) and the second buffer tank (2) are both connected to the stationary tank (3) through the air supply pipe (4), and the air supply pipe (4) is provided with a first valve (7).

3. A liquid injection and gas supply system according to claim 2, characterized in that: The first buffer tank (1) is connected to the main gas supply pipe (4) via a first gas supply branch pipe (5), and the second buffer tank (2) is connected to the main gas supply pipe (4) via a second gas supply branch pipe (6).

4. A liquid injection and gas supply system according to claim 3, characterized in that: The first gas supply branch pipe (5) is provided with a second valve (8), and the second gas supply branch pipe (6) is provided with a third valve (9); the first valve (7), the second valve (8), and the third valve (9) are all remotely controlled electrical valves.

5. The liquid injection and gas supply system according to claim 1, characterized in that: The first buffer tank (1) and the second buffer tank (2) are both provided with pressure gauges, and the first buffer tank (1) is provided with a moisture detector and a drying and dewatering device.

6. A liquid injection and gas supply system according to claim 1, characterized in that: The stationary tank (3) is connected to an exhaust pipe (11), and the exhaust pipe (11) is provided with a fourth valve (12) and a vacuum pump (13).

7. A liquid injection and gas supply control method using a liquid injection and gas supply system according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1, connecting the static tank (3) and the first buffer tank (1), so that the gas enters the first buffer tank (1) from the static tank (3); Step 2: After the pressures of the static tank (3) and the first buffer tank (1) are balanced, disconnect the static tank (3) from the first buffer tank (1); Step 3, the standing tank (3) is vented and vacuumized; Step 4, connecting the static tank (3) with the first buffer tank (1), inflating the static tank (3) through the first buffer tank (1), and disconnecting the connection between the static tank (3) and the first buffer tank (1) when the pressures of the first buffer tank (1) and the static tank (3) are the same; Step 5, connecting the static tank (3) and the second buffer tank (2), and inflating the static tank (3) through the second buffer tank (2) until the set pressure is reached; Step 6: The static tank (3) is filled with liquid for the battery. After the filling is completed, proceed to step 1.

8. A liquid injection gas supply control method according to claim 7, characterized in that: The first buffer tank (1) is connected to the stationary tank (3) by opening the first valve (7) and the second valve (8), and the second buffer tank (2) is connected to the stationary tank (3) by opening the first valve (7) and the third valve (9).

9. A liquid injection gas supply control method according to claim 7, characterized in that: In step 1, the gas entering the first buffer tank (1) is tested for moisture. In step 3, the gas entering the static tank (3) from the first buffer tank (1) is tested for moisture. A moisture content threshold is set. If the moisture content threshold is exceeded, the gas needs to be dried and dehydrated.

10. A liquid injection gas supply control method according to claim 7, characterized in that: In step 4, high-pressure gas is firstly charged into the second buffer tank (2) through the air intake pipe (10), and when the second buffer tank (2) is connected to the static tank (3), the second buffer tank (2) charges the static tank (3) with gas, and at the same time, the air intake pipe (10) replenishes the high-pressure gas into the second buffer tank (2).

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