Protective gas control device for negative electrode liquid storage tank of all-vanadium redox flow battery

Abstract

The utility model discloses a protective gas control device for a negative electrode liquid storage tank of an all-vanadium redox flow battery, which comprises a gas storage tank connected to the liquid storage tank through a gas supply pipe, and an opening and closing electromagnetic valve connected to the gas supply pipe; the gas concentration detection module is used for detecting the concentration of hydrogen and oxygen in the liquid storage tank, and when the gas concentration detection module detects that the concentration of hydrogen in the liquid storage tank exceeds a first concentration threshold value or the concentration of oxygen in the liquid storage tank exceeds a second concentration threshold value, the opening and closing electromagnetic valve is opened to inject inert gas into the liquid storage tank; the first pressure detection meter is used for detecting a first air pressure value in the liquid storage tank in real time; when the first air pressure value reaches the high-pressure threshold value range, the single exhalation valve discharges air in the liquid storage tank; and the emergency exhaust valve is connected to the liquid storage tank. And when the hydrogen concentration exceeds the first concentration threshold value or the oxygen concentration exceeds the second concentration threshold value, the gas storage tank supplements inert gas into the liquid storage tank, so that the oxidation reaction of the electrolyte is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of liquid flow battery especially relates to a kind of protective gas control device of full vanadium liquid flow battery negative electrode liquid storage tank. BACKGROUND

[0002] Full vanadium liquid flow battery is a kind of redox battery with vanadium as active substance in circulating flow liquid state, positive electrolyte is oxidized when charging, and reduced when discharging;Negative electrolyte is contrary, reduced when charging, and oxidized when discharging, and negative electrolyte is easy to be oxidized.

[0003] In open system, V (II) in negative electrolyte is oxidized into V (III), causing energy loss, reducing battery capacity density, shortening battery cycle life.And using closed system, and inert gas protection can effectively reduce the oxidation rate of negative low valence vanadium ion, and further reduce energy loss, improve battery cycle life.

[0004] Electrolyte will produce H2, O2, SO2 and other gases when charging and discharging, these gases gather to the upper portion of electrolyte liquid storage tank, after long-term operation, the pressure of the upper portion of electrolyte liquid storage tank is increased, the pressure resistance requirement of the whole system is improved, and the project cost is increased, at the same time, it can also corrode precision instruments such as sensor, reduce service life;Therefore, these gases need to be treated in time, but if these gases are not properly treated, the operation of the whole system will be affected, and the battery cycle life will be shortened. UTILITY MODEL CONTENTS

[0005] In order to overcome the shortcomings of prior art, the purpose of the utility model is to provide a kind of protective gas control device of full vanadium liquid flow battery negative electrode liquid storage tank, with the advantages of reducing electrolyte oxidation reaction and effectively treating reaction gas.

[0006] The purpose of the utility model is realized by the following technical scheme:

[0007] According to the embodiment of the present disclosure, a kind of protective gas control device of full vanadium liquid flow battery negative electrode liquid storage tank is provided, comprising:

[0008] gas supply pipe is connected to the liquid storage tank, and gas storage tank for storing inert gas is connected to the gas supply pipe, and on-off electromagnetic valve is connected to the gas supply pipe, for controlling the gas supply pipe to be conducted or closed to control the circulation of inert gas;

[0009] gas concentration detection module is connected to the liquid storage tank, and the concentration of hydrogen and oxygen in the liquid storage tank is detected, when the gas concentration detection module detects that the concentration of hydrogen in the liquid storage tank exceeds the first concentration threshold or the concentration of oxygen exceeds the second concentration threshold, the on-off electromagnetic valve is opened to inject inert gas into the liquid storage tank;

[0010] a first pressure detection table connected to the liquid storage tank, configured to detect a first gas pressure value in the liquid storage tank in real time;

[0011] a single call valve connected to the liquid storage tank, configured to discharge gas in the liquid storage tank when the first gas pressure value reaches a high pressure threshold range; and

[0012] an emergency exhaust valve connected to the liquid storage tank, configured to open to discharge gas when the first gas pressure value exceeds the highest value of the high pressure threshold range.

[0013] To achieve the above technical solutions, the all-vanadium redox flow battery system applied in the device adopts a closed system. When the all-vanadium redox flow battery system starts to operate, the on-off electromagnetic valve is opened and the emergency exhaust valve is closed, and the gas in the upper part of the liquid storage tank is replaced with inert gas by the gas storage tank. After the replacement is completed, the gas pressure in the liquid storage tank is controlled to be within a preset working gas pressure, and the on-off electromagnetic valve is closed. During the operation of the all-vanadium redox flow battery system, the first pressure detection table is used to detect the first gas pressure value in the liquid storage tank in real time, and the gas concentration detection module is used to detect the concentrations of hydrogen and oxygen in the liquid storage tank in real time. When the first gas pressure value is within the preset working gas pressure and the hydrogen concentration exceeds a first concentration threshold or the oxygen concentration exceeds a second concentration threshold, the on-off electromagnetic valve is controlled to be opened again, and inert gas is replenished into the liquid storage tank, so as to reduce the oxidation reaction of the electrolyte, until the hydrogen concentration and the oxygen concentration decrease to the normal range again, and then the on-off electromagnetic valve is closed again. When the first gas pressure value reaches the high pressure threshold range, it indicates that the gas pressure in the liquid storage tank is too high, and the single call valve is opened to discharge the gas in the liquid storage tank, until the first gas pressure value decreases to the preset working gas pressure again, and then the single call valve is closed again. When the first gas pressure value exceeds the highest value of the high pressure threshold range, it indicates that the gas pressure in the liquid storage tank is too high, and the single call valve cannot meet the demand of gas discharge and pressure relief or the single call valve fails, and the emergency exhaust valve is opened to discharge a large amount of gas, so as to maintain the stability of the gas pressure in the liquid storage tank and achieve effective treatment of the reaction gas.

[0014] In some exemplary embodiments, a second pressure detection table and a safety valve are further connected to the gas supply pipe. The second pressure detection table is configured to detect a second gas pressure value in the gas supply pipe in real time, and the safety valve is opened to discharge inert gas outward when the second gas pressure value exceeds a high pressure warning value.

[0015] To achieve the above technical solutions, the second pressure detection table is used to detect the second gas pressure value in the gas supply pipe in real time, and the safety valve is in a closed state under normal circumstances. When the second gas pressure value exceeds the high pressure warning value, the safety valve is opened to discharge gas to prevent the gas pressure in the gas supply pipe from being too high and causing damage, and to ensure the stability of the system operation.

[0016] In some exemplary embodiments, a pressure reducing valve is further connected to the gas supply pipe, configured to reduce the gas pressure discharged by the gas storage tank.

[0017] The above technical solution is realized, the inert gas discharged by the gas tank is first subjected to pressure reduction treatment by the pressure reducing valve, so that the impact on the gas supply pipe is reduced, and the stability of system operation is ensured.

[0018] In some exemplary embodiments, a on-off ball valve is further connected to the gas supply pipe, and is used for controlling the on-off connection between the gas tank and the liquid tank.

[0019] The above technical solution is realized, the on-off ball valve is normally in the on state, and when maintenance or other operations are performed, the on-off ball valve can be closed to isolate the gas tank from the liquid tank.

[0020] In some exemplary embodiments, the gas concentration detection module comprises a hydrogen concentration detector, which is used for detecting the hydrogen concentration in the gas tank and generating a first gas concentration value; and an oxygen concentration detector, which is used for detecting the oxygen concentration in the gas tank and generating a second gas concentration value.

[0021] In summary, compared with the prior art, the utility model has the following beneficial effects:

[0022] The utility model discloses an all -vanadium redox flow battery negative pole liquid storage tank protection gas control device, when all -vanadium redox flow battery system starts operation, first open -and -close electromagnetic valve, close emergency exhaust valve, by the gas tank gas supply with the gas of the upper portion of liquid storage tank is replaced for inert gas, after replacement, control the gas pressure in the liquid storage tank is in the preset work gas pressure, close on -and -off electromagnetic valve, in the process of all -vanadium redox flow battery system operation, through the first pressure detection table real -time detection the first gas pressure value in the liquid storage tank, through gas concentration detection module real -time detection the concentration of hydrogen and oxygen in the liquid storage tank, when the first gas pressure value is in the preset work gas pressure, and hydrogen concentration exceeds first concentration threshold value or oxygen concentration exceeds second concentration threshold value, control on -and -off electromagnetic valve to open again, re -inert gas is supplemented to the liquid storage tank, thereby reducing electrolyte oxidation reaction, until hydrogen concentration and oxygen concentration drop to normal range again close on -and -off electromagnetic valve again, when the first gas pressure value reaches high pressure threshold range, then indicate that the gas pressure in the liquid storage tank is too high, open single call valve and discharge the gas in the liquid storage tank until the first gas pressure value drops to the preset work gas pressure again close single call valve again, when the first gas pressure value exceeds the highest value of high pressure threshold range, then explain that the gas pressure in the liquid storage tank is too high, and single call valve can not satisfy the demand of exhaust pressure relief or single call valve has failed, open emergency exhaust valve and discharge a large amount of gas at this time, maintain the stability of the gas pressure in the liquid storage tank, realize the effective treatment of reaction gas. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a structural schematic view of the utility model embodiment.

[0024] Corresponding component names represented by numbers and letters in the figure:

[0025] 10, liquid storage tank; 11, first pressure detection meter; 12, single call valve; 13, emergency exhaust valve; 20, gas storage tank; 21, gas supply pipe; 22, on-off electromagnetic valve; 23, second pressure detection meter; 24, safety valve; 25, pressure reducing valve; 26, on-off ball valve; 31, hydrogen concentration detector; 32, oxygen concentration detector. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0027] As shown in the drawings, Figure 1 The present application provides a kind of negative electrode liquid storage tank protection gas control device of all-vanadium redox battery, it include: by one gas supply pipe 21 connection in liquid storage tank 10, for storing inert gas gas storage tank 20, gas supply pipe 21 is connected with on-off electromagnetic valve 22, for control gas supply pipe 21 conduction or close to control the circulation of inert gas;Gas concentration detection module connected to liquid storage tank 10, for detecting the concentration of hydrogen and oxygen in liquid storage tank 10, when gas concentration detection module detects that the hydrogen concentration in liquid storage tank 10 exceeds the first concentration threshold or the oxygen concentration exceeds the second concentration threshold, on-off electromagnetic valve 22 opens to inject inert gas into liquid storage tank 10;First pressure detection meter 11 connected to liquid storage tank 10, for real-time detection of the first gas pressure value in liquid storage tank 10;Single call valve 12 connected to liquid storage tank 10, when the first gas pressure value reaches the high pressure threshold range, single call valve 12 discharges the gas in liquid storage tank 10;And, emergency exhaust valve 13 connected to liquid storage tank 10, when the first gas pressure value exceeds the highest value of high pressure threshold range, emergency exhaust valve 13 opens to exhaust.

[0028] Second pressure detection meter 23 and safety valve 24 are also connected to gas supply pipe 21, second pressure detection meter 23 is used for real-time detection of the second gas pressure value in gas supply pipe 21, and when the second gas pressure value exceeds the high pressure early warning value, safety valve 24 opens to discharge inert gas outward;The second gas pressure value in gas supply pipe 21 is detected in real time by second pressure detection meter 23, and safety valve 24 is in a closed state under normal circumstances, when the second gas pressure value exceeds the high pressure early warning value, safety valve 24 opens to exhaust and relieve pressure, to prevent the gas pressure in gas supply pipe 21 from being too high and causing damage, and to ensure the stability of system operation.

[0029] A pressure reducing valve 25 is further connected to the gas supply pipe 21 for reducing the pressure of the inert gas discharged from the gas tank 20. The pressure reducing valve 25 is located on the gas supply pipe 21 near the gas tank 20, and the inert gas discharged from the gas tank 20 is first subjected to pressure reduction by the pressure reducing valve 25, thereby reducing the impact on the gas supply pipe 21 and ensuring the stability of the system operation. A on-off ball valve 26 is further connected to the gas supply pipe 21 for controlling the on-off connection between the gas tank 20 and the liquid tank 10. The on-off ball valve 26 is normally in an on state, and when maintenance or other operations are performed, the on-off ball valve 26 can be closed to isolate the gas tank 20 from the liquid tank 10.

[0030] The gas concentration detection module includes a hydrogen concentration detector 31 for detecting the hydrogen concentration in the gas tank 20 and generating a first gas concentration value, and an oxygen concentration detector 32 for detecting the oxygen concentration in the gas tank 20 and generating a second gas concentration value. The first concentration threshold is 4%, and the second concentration threshold is 3%. When the first gas concentration value exceeds the first concentration threshold or the second gas concentration value exceeds the second concentration threshold, the on-off electromagnetic valve 22 is opened to inject inert gas into the liquid tank 10.

[0031] The single call valve 12 can be a one-way valve with elastic force. When the first gas pressure value reaches the high pressure threshold range, the gas pressure can overcome the elastic force to open the one-way valve for exhaust. The high pressure threshold range is generally set to 2-4 Kpa, and the emergency exhaust valve 13 is opened for emergency and rapid exhaust when the first gas pressure value exceeds the highest value of the high pressure threshold range. It can be understood that when the high pressure threshold range is set to 2-4 Kpa, the highest value is 4 Kpa.

[0032] The all-vanadium redox flow battery system to which the device is applied adopts a closed system, and it can be understood that the device is connected with a battery control system, receives collected data and sends control signals by the battery control system, when the all-vanadium redox flow battery system starts to operate, the opening and closing electromagnetic valve is opened and the emergency exhaust valve 13 is closed, the gas in the upper part of the liquid storage tank 10 is replaced with inert gas supplied by the gas storage tank 20, after the replacement is completed, the gas pressure in the liquid storage tank 10 is controlled to be within a preset working gas pressure, the opening and closing electromagnetic valve 22 is closed, and the preset working gas pressure can be set to 0-2KPa; during the operation of the all-vanadium redox flow battery system, the first gas pressure value in the liquid storage tank 10 is detected in real time through the first pressure detection table 11, and the concentration of hydrogen and oxygen in the liquid storage tank 10 is detected in real time through the gas concentration detection module, when the first gas pressure value is within the preset working gas pressure, and the hydrogen concentration exceeds the first concentration threshold or the oxygen concentration exceeds the second concentration threshold, the opening and closing electromagnetic valve 22 is controlled to be opened again, and the inert gas is replenished into the liquid storage tank 10 again, so as to reduce the oxidation reaction of the electrolyte, and the opening and closing electromagnetic valve 22 is closed again after the hydrogen concentration and the oxygen concentration decrease to the normal range again; when the first gas pressure value reaches the high pressure threshold range, it indicates that the gas pressure in the liquid storage tank 10 is too high, at this time, the single call valve 12 is opened to discharge the gas in the liquid storage tank 10, and the single call valve 12 is closed again after the first gas pressure value decreases to the preset working gas pressure again, and when the first gas pressure value exceeds the highest value of the high pressure threshold range, it indicates that the gas pressure in the liquid storage tank 10 is too high, the single call valve 12 cannot meet the demand of exhaust pressure relief or the single call valve 12 fails, at this time, the emergency exhaust valve 13 is opened to discharge a large amount of gas, so as to maintain the stability of the gas pressure in the liquid storage tank 10 and realize the effective treatment of the reaction gas.

[0033] The all-vanadium redox flow battery negative electrode liquid storage tank protection gas control device can not only reduce the oxidation reaction of the negative electrode electrolyte, but also guide the gas flow, stabilize the system pressure, reduce the corrosion of the instrument, ensure the safe operation of the system, improve the circulation frequency of the electrolyte and prolong the service life of the all-vanadium redox flow battery.

[0034] The above embodiments only express several implementation manners of the utility model, the description is more specific and detailed, but it cannot be understood as the limitation of the utility model patent range. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the utility model, a number of deformations and improvements can be made, which are equivalent modifications and evolutions of the above embodiments according to the essential technology of the utility model, and these all belong to the protection range of the utility model.

Claims

1. A protective gas control device for the negative electrode storage tank of a vanadium redox flow battery, characterized in that, include: A gas supply pipe is connected to a liquid storage tank for storing inert gas. The gas supply pipe is equipped with an on / off solenoid valve to control the opening or closing of the gas supply pipe to control the flow of inert gas. A gas concentration detection module connected to the liquid storage tank is used to detect the concentration of hydrogen and oxygen in the liquid storage tank. When the gas concentration detection module detects that the hydrogen concentration in the liquid storage tank exceeds a first concentration threshold or the oxygen concentration exceeds a second concentration threshold, the opening and closing solenoid valve opens to inject inert gas into the liquid storage tank. A first pressure gauge connected to the liquid storage tank is used to detect the first air pressure value inside the liquid storage tank in real time. A single-exit valve connected to the liquid storage tank will discharge gas from the liquid storage tank when the first gas pressure value reaches the high pressure threshold range. as well as, An emergency vent valve connected to the liquid storage tank opens to release air when the first air pressure value exceeds the highest value of the high pressure threshold range.

2. The protective gas control device for the negative electrode storage tank of a vanadium redox flow battery according to claim 1, characterized in that, The gas supply pipe is also connected to a second pressure gauge and a safety valve. The second pressure gauge is used to detect the second gas pressure value in the gas supply pipe in real time. When the second gas pressure value exceeds the high pressure warning value, the safety valve opens to release inert gas.

3. The protective gas control device for the negative electrode storage tank of a vanadium redox flow battery according to claim 1 or 2, characterized in that, The gas supply pipe is also connected to a pressure reducing valve, which is used to reduce the gas pressure discharged from the gas storage tank.

4. The protective gas control device for the negative electrode storage tank of a vanadium redox flow battery according to claim 1 or 2, characterized in that, The gas supply pipe is also connected to an on / off ball valve, which is used to control the connection between the gas storage tank and the liquid storage tank.

5. The protective gas control device for the negative electrode storage tank of a vanadium redox flow battery according to claim 1, characterized in that, The gas concentration detection module includes: a hydrogen concentration detector for detecting the hydrogen concentration in the gas storage tank and generating a first gas concentration value; and an oxygen concentration detector for detecting the oxygen concentration in the gas storage tank and generating a second gas concentration value.

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