A device and method for testing oxidation resistance of flow battery membrane

Abstract

The present invention discloses a device for testing the oxidation resistance of a flow battery membrane, which relates to the technical field of flow battery membrane testing and solves the problem of being unable to simulate the actual operating state of the ion exchange membrane and accurately reflect the membrane's oxidation resistance during battery operation. + The present invention relates to a technical problem that the flow rate of the electrolyte in the test is not easy to adjust at any time and may affect the test results of the liquid flow battery membrane performance; including: a liquid flow battery pack, wherein an ion exchange membrane is embedded inside the liquid flow battery pack; the test results of the present invention are more obvious than the concentration change trend of the comparative example, avoiding the comparative example test method not taking into account the flow of the electrolyte in actual application conditions, and at the same time avoiding the influence of local concentration changes of the comparative example immersed in the electrolyte. The oxidation test method is convenient and fast. At the same time, the flow rate and flow velocity of the electrolyte can be adjusted during the test to reduce the factors affecting the ion exchange membrane performance test.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid flow battery membrane testing, and in particular relates to a device and method for testing the oxidation resistance of a liquid flow battery membrane. Background Art

[0002] A flow battery is an energy storage system that reversibly converts electrical energy into chemical energy. A flow battery energy storage system consists of multiple monolithic flow cells connected in series. Liquid electrolyte is pumped from a storage tank to the flow electrodes in the battery stack by a flow pump. The reaction generates electrons, which flow through an external circuit. Between the electrodes is an ion exchange membrane, or separator, which prevents the two electrolytes from mixing. Therefore, research on ion exchange membranes with excellent overall performance has become a hot topic in the flow battery field.

[0003] The current oxidation resistance test for ion exchange membranes involves immersing the membrane in an H2SO4 solution containing only VO2+ for a period of time. The VO2+ concentration in the solution is then measured using a UV spectrophotometer and compared with a blank H2SO4 solution containing VO2+ but without the membrane. This method cannot simulate the actual operating state of the ion exchange membrane and cannot accurately reflect the membrane's oxidation by VO2+ during battery operation. In addition, the electrolyte flow rate during the test is not easy to adjust at any time, which may also affect the performance test results of the flow battery membrane. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes a device and method for testing the oxidation resistance of a flow battery membrane.

[0005] A device for testing the oxidation resistance of a flow battery membrane, comprising:

[0006] A liquid flow battery pack having an ion exchange membrane embedded therein;

[0007] A liquid storage tank is installed behind the liquid flow battery pack, and a circulation pump for circulating electrolyte is provided between the liquid storage tank and both sides of the liquid flow battery pack;

[0008] A flow control device for regulating the flow rate of the electrolyte is installed between the circulation pump and the liquid flow battery pack, and the flow control device includes a flow box for storing the electrolyte, a bubble elimination component for eliminating bubbles in the electrolyte in the flow box, and a regulating component for regulating the flow rate of the electrolyte.

[0009] Preferably, a shallow water chamber and a deep water chamber are opened inside the flow box, and the bubble elimination component and the regulating component are respectively located in the shallow water chamber and the deep water chamber.

[0010] Preferably, the regulating component for regulating the liquid flow distance from the inner wall of the deep water chamber includes:

[0011] Front and rear regulating buffer plates are staggeredly installed on the front and rear inner walls of the deep water chamber, and the upper surfaces of the outer ends of the front and rear regulating buffer plates pass through the flow box and are exposed to the outside;

[0012] A front rotating rod and a rear rotating rod mounted on the upper surface of the flow box and changing the angle of the rotating shaft;

[0013] A lower bevel gear is sleeved on the rotating shaft, and an upper bevel gear is sleeved on the front rotating rod and meshes with the lower bevel gear.

[0014] Preferably, a hand wheel is provided at one end of the front rotating rod, and a stable seat for supporting the front rotating rod and the rear rotating rod is provided on the upper surface of the flow box.

[0015] Preferably, the bubble elimination component installed inside the shallow water chamber to eliminate bubbles includes:

[0016] Rotate two mounting shafts mounted inside the shallow water chamber;

[0017] A plurality of bubble elimination rods are circumferentially mounted on the mounting shaft;

[0018] and a driving motor mounted on the upper end of one of the mounting shafts.

[0019] Preferably, a synchronization component is provided between the front rotating rod and the rear rotating rod, and the synchronization component includes a lower rack vertically located below the front rotating rod and the rear rotating rod, and the front rotating rod and the rear rotating rod are both provided with a fixed gear meshing with the lower rack.

[0020] Preferably, an electrode plate is provided on the outside of the flow battery pack, and a cooling member for cooling the electrode plate is provided on the outside of the electrode plate, and the cooling member includes:

[0021] A heat-insulating shell installed on the outer surface of the electrode plate, wherein a refrigeration coil is arranged inside the heat-insulating shell and is in contact with the outer side of the electrode plate;

[0022] A cooling coil is located outside the refrigeration coil, a drainage pipe is provided between one end of the cooling coil and the top of the liquid flow battery pack, and a connecting water pipe is provided between the other end of the cooling coil and the liquid storage tank.

[0023] Preferably, a horizontal plate is horizontally arranged inside the heat-insulating shell, an electric telescopic rod is arranged on the upper surface of the heat-insulating shell, and the telescopic rod arranged inside the electric telescopic rod is fixed on the upper surface of the horizontal plate.

[0024] Preferably, an adsorption sleeve that is sleeved on the refrigeration coil is provided on the upper surface of the horizontal plate, and a guide rod that movably passes through the end of the horizontal plate is provided on the inner wall of the heat-insulating shell.

[0025] A method for testing the oxidation resistance of a flow battery membrane comprises the following steps:

[0026] S1. Prepare a certain amount of 1.5M VOSO4 and H2SO4 electrolyte with different concentrations, preferably 2-3M;

[0027] S2. Inject the electrolyte prepared in step 1 into the vanadium flow battery pack. The volume of the positive electrode electrolyte is twice that of the negative electrode. Then charge the battery continuously. The electric density is 80-160mA / cm 2 Preferably 120 mA / cm 2 ;

[0028] S3, the VO2 prepared by the positive electrode + H2SO4 solution, detected by UV spectrophotometer, VO 2+ The concentration was lower than the detection limit of UV-visible spectrophotometer, indicating that VO 2+ Completely converted into VO2 + ;

[0029] S4, assembling the flow battery group to be tested, with the ion exchange membrane to be tested in the middle, and the ion membrane thickness is 50 microns or 60 microns;

[0030] S5. Connect the circulation pumps on both sides of the assembled liquid flow battery pack, and connect the same liquid flow battery pack at the same time, and inject a certain volume of VO2 into the liquid flow battery pack. + The test solution is circulated to both sides of the test fixture using a circulation pump;

[0031] S6. Take part of the solution in the liquid storage tank 103 and test VO at different test times. 2+ If the solution contains VO 2+ , indicating that the ion exchange membrane 101 is VO2 + Oxidation, local degradation has occurred, VO 2+ The higher the concentration, the worse the oxidation resistance of the membrane.

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

[0033] (1) The test results of the present invention are more obvious than the concentration change trend of the comparative example, which avoids the comparative example test method not taking into account the flow of the electrolyte in actual application conditions, and at the same time avoids the influence of local concentration changes when the comparative example is immersed in the electrolyte. The oxidizability test method is convenient and fast. At the same time, during the test process, the flow rate and flow velocity of the electrolyte can be controlled to reduce the factors affecting the ion exchange membrane performance test.

[0034] (2) The bubble elimination component designed in the present invention can mechanically stir the electrolyte entering the flow box, puncture the bubbles, reduce the mechanical stirring, and physically break the internal tiny bubbles by needle means, and remove the bubbles by vacuuming, thereby reducing the impact of bubbles on the ion exchange membrane test process.

[0035] (3) The cooling component designed in the present invention can dissipate heat from the temperature generated by the working electrode plates, so that the liquid flow battery pack and the electrolyte circulating inside can maintain a suitable temperature, reducing the impact of high temperature on the test results of the ion exchange membrane. At the same time, the electrolyte flowing back into the liquid storage tank can be cooled, which is convenient for recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of a flow battery membrane oxidation resistance testing device according to the present invention;

[0037] Figure 2 This is a schematic diagram of the left side structure of the battery membrane oxidation resistance testing device of the present invention;

[0038] Figure 3 For the present invention Figure 2 a cross-sectional view of the flow control device;

[0039] Figure 4 For the present invention Figure 3 Schematic diagram of the structure of the bubble elimination component;

[0040] Figure 5 For the present invention Figure 3 Schematic diagram of the structure of the control component;

[0041] Figure 6 For the present invention Figure 5 Structural diagram of the synchronization component;

[0042] Figure 7 For the present invention Figure 1 A schematic side view of the structure of the middle cooling component;

[0043] Figure 8 For the present invention Figure 7 Enlarged view of area A in the middle;

[0044] Figure 9 For the present invention Figure 5 Schematic diagram of the top view of the central control component;

[0045] In the figure: 100, liquid flow battery pack; 101, ion exchange membrane; 102, power supply; 103, liquid storage tank; 104, circulation pump; 105, electrode plate; 200, flow control device; 201, flow box; 2011, deep water chamber; 2012, shallow water chamber; 202, bubble elimination member; 2021, mounting shaft; 2022, bubble elimination rod; 2023, drive motor; 203, control member; 2031, front control buffer plate; 2032, rear control buffer plate; 2033, rotating shaft; 20 34. Front rotating rod; 2035. Rear rotating rod; 2036. Lower bevel gear; 2037. Upper bevel gear; 204. Water inlet pipe; 205. Water supply pipe; 206. Synchronizing component; 2061. Lower rack; 2062. Fixed gear; 207. Vacuum suction pipe; 300. Cooling component; 301. Insulation shell; 302. Refrigeration coil; 303. Cooling coil; 304. Drain pipe; 305. Connecting water pipe; 306. Electric telescopic rod; 307. Horizontal plate; 308. Adsorption sleeve; 309. Guide rod. DETAILED DESCRIPTION

[0046] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0047] Example 1

[0048] See also Figure 1 - Figure 5 and Figure 9 The present application provides a device for testing the oxidation resistance of a flow battery membrane, comprising:

[0049] A liquid flow battery 100 , wherein an ion exchange membrane 101 is embedded in the liquid flow battery 100 ;

[0050] A liquid storage tank 103 is installed behind the liquid flow battery pack 100. A circulation pump 104 for circulating electrolyte is provided between the liquid storage tank 103 and both sides of the liquid flow battery pack 100. The electrolyte can be circulated to both sides of the liquid flow battery pack 100.

[0051] A flow control device 200 is installed between the circulation pump 104 and the liquid flow battery pack 100 to control the flow rate of the electrolyte. The flow control device 200 includes a flow box 201 for storing the electrolyte, a bubble elimination component 202 for eliminating bubbles in the electrolyte in the flow box 201, and a control component 203 for controlling the flow rate of the electrolyte.

[0052] In this embodiment, preferably, a shallow water chamber 2012 and a deep water chamber 2011 are opened inside the flow box 201, and a water inlet pipe 204 and a water supply pipe 205 respectively connected to the shallow water chamber 2012 and the deep water chamber 2011 are provided on both sides of the flow box 201. A vacuum suction pipe 207 connected to the deep water chamber 2011 is provided on the upper surface of the flow box 201. The bubble elimination component 202 and the regulating component 203 are respectively located in the shallow water chamber 2012 and the deep water chamber 2011. The shallow water chamber 2012 can be used to puncture bubbles, and the vacuum suction pipe 207 is connected to an external vacuum suction device to suck away the gas generated by puncturing the bubbles, thereby eliminating electrolyte bubbles and reducing the influence of bubbles on the performance test of the ion exchange membrane 101.

[0053] In this embodiment, preferably, the regulating component 203 for regulating the liquid flow distance from the inner wall of the deep water chamber 2011 includes:

[0054] The front regulating buffer plates 2031 and the rear regulating buffer plates 2032 are staggeredly installed on the front and rear inner walls of the deep water chamber 2011. The space between the front regulating buffer plates 2031 and the rear regulating buffer plates 2032 and the inner wall of the deep water chamber 2011 is adjustable. The upper surfaces of the outer ends of the front regulating buffer plates 2031 and the rear regulating buffer plates 2032 pass through the flow box 201 and are exposed to the outside.

[0055] A front rotating rod 2034 and a rear rotating rod 2035 are mounted on the upper surface of the flow box 201 and change the angle of the rotating shaft 2033. The two rotating rods can rotate synchronously;

[0056] A lower bevel gear 2036 is sleeved on the rotating shaft 2033 and an upper bevel gear 2037 is sleeved on the front rotating rod 2034 and meshes with the lower bevel gear 2036 . The upper bevel gear 2037 and the lower bevel gear 2036 mesh with each other.

[0057] In this embodiment, preferably, a handwheel is provided at one end of the front rotating rod 2034, and a stable seat is provided on the upper surface of the flow box 201 to support the front rotating rod 2034 and the rear rotating rod 2035, which does not affect the rotation of the rotating rods but can support them.

[0058] In summary, before the battery pack is tested, the flow rate of the liquid can be adjusted, and the hand wheel is held to drive the front rotating rod 2034 to rotate. The hand wheel can also be set with corresponding limiting measures, such as using bolt connection limiters. The manual holding of the hand wheel can be replaced by a mechanical drive, such as a motor, and the force driving the buffer plate to rotate is greater than the flow impact it receives, which will not affect the rotation of the buffer plate. The upper bevel gear 2037 on the front rotating rod 2034 rotates, and due to the action of the synchronization component 206, the rear rotating rod 2035 is driven to rotate synchronously, and the upper bevel gear 2037 on the rear rotating rod 2035 rotates, driving the lower bevel gear 2036 meshing with the upper bevel gear 2037 to rotate synchronously, driving the rotating shaft 2033 to rotate, and driving the front regulating buffer plate 2031 and the rear regulating buffer plate 2032 to rotate around the rotating shaft 2033 connected thereto, thereby changing the space between the buffer plate and the inner wall of the deep water chamber 2011. As the space becomes larger, the flow rate of the electrolyte becomes larger, and the front regulating buffer plate 203 1 and the rear regulating buffer plates 2032 are staggered, and the number of buffer plates can be set as needed. A wavy channel is formed between the buffer plate and the deep water chamber 2011, so that when the electrolyte passes through the wavy channel, it will impact the surface of the buffer plate, slowing down the electrolyte flow rate, and the larger the angle formed by the buffer plate and the inner wall of the deep water chamber 2011, the flatter the wavy channel formed, and the greater the electrolyte flow rate. When the electrolyte flow volume and flow rate are adjusted to a suitable electrolyte flow volume and flow rate, the circulation pump 104 sucks the prepared electrolyte in the liquid storage tank 103 into the flow box 201, first passes through the bubble elimination component 202 in the shallow water chamber 2012 to eliminate bubbles, and the electrolyte after bubble elimination enters the deep water chamber 2011, and then passes through the regulating component 203 to change the electrolyte flow rate. At the same time, the vacuum suction tube 207 discharges gas to eliminate bubbles, and the electrolyte enters the liquid flow battery pack 100 at a suitable rate to test the oxidation resistance of the ion exchange membrane 101 and record various test data.

[0059] Example 2

[0060] Reference Figure 6 , which is the second embodiment of the present invention.

[0061] In this embodiment, preferably, a bubble elimination component 202 is provided to mechanically stir the electrolyte entering the flow box 201, puncture bubbles, reduce mechanical stirring, physically puncture the internal tiny bubbles by needles, and remove the bubbles by vacuuming, thereby reducing the impact of bubbles on the ion exchange membrane 101 during the test process. The bubble elimination component 202 installed inside the shallow water chamber 2012 for eliminating bubbles includes:

[0062] The two mounting shafts 2021 are rotatably mounted inside the shallow water chamber 2012. The upper ends of the two mounting shafts 2021 penetrate the flow box 201 and are exposed to the outside. The upper ends of the two mounting shafts 2021 are respectively provided with two pulleys, and the two pulleys are provided with belts to achieve synchronous rotation of the two mounting shafts 2021 and the bubble elimination rod 2022.

[0063] The plurality of bubble elimination rods 2022 are circumferentially mounted on the mounting shaft 2021, and the ... Figure 6 It can be seen that the surface of the bubble elimination rod 2022 is evenly provided with a plurality of needle-shaped rods. As the needle-shaped rods rotate, the tips of the needle-shaped rods can puncture bubbles. During the entire test process of the battery pack, only the internal liquid flows in the flow box 201, and no new gas enters, and no new bubbles are generated. The bubbles are only eliminated before the liquid flows into the liquid flow battery pack 100.

[0064] And a driving motor 2023 installed on the upper end of one of the mounting shafts 2021.

[0065] In summary, when in use, the electrolyte enters the flow box 201, the drive motor 2023 works, and drives one of the installation shafts 2021 to rotate. Since the two installation shafts 2021 are connected by pulleys and belts, the two installation shafts 2021 rotate synchronously, driving the bubble elimination rod 2022 on the installation shaft 2021 to rotate, mechanically puncturing the electrolyte flowing through, and eliminating bubbles in the electrolyte.

[0066] In this embodiment, preferably, a synchronization component 206 is provided between the front rotating rod 2034 and the rear rotating rod 2035. The synchronization component 206 can drive the relatively distributed front regulating buffer plate 2031 and the rear regulating buffer plate 2032 to rotate synchronously, thereby changing the distance between the free ends of the two buffer plates and the inner wall of the flow box 201, thereby regulating the electrolyte flow rate. The synchronous adjustment is convenient and fast. The synchronization component 206 includes a lower rack 2061 vertically located below the front rotating rod 2034 and the rear rotating rod 2035. A guide groove is provided on the lower surface of the lower rack 2061, and a guide block extending into the guide groove is provided on the upper surface of the flow box 201. The front rotating rod 2034 and the rear rotating rod 2035 are both provided with a fixed gear 2062 engaged with the lower rack 2061.

[0067] In summary, when in use, hold the handwheel of the front rotating rod 2034 to rotate it, driving the upper bevel gear 2037 on the front rotating rod 2034 to engage with the lower bevel gear 2036, driving the fixed gear 2062 on the front rotating rod 2034 to rotate, and the fixed gear 2062 drives the lower rack 2061 engaged with it to move, and the movement of the lower rack 2061 drives the other fixed gear 2062 engaged with it to rotate, thereby driving the rear rotating rod 2035 to rotate, thereby driving the rear rotating rod 2035 and the bevel gear on it to rotate, and using the synchronization component 206, the front regulating buffer plate 2031 and the rear regulating buffer plate 2032 distributed on both sides to rotate simultaneously, changing the distance between the front regulating buffer plate 2031 and the rear regulating buffer plate 2032 and the inner wall of the flow box 201, thereby changing the electrolyte circulation volume and circulation rate.

[0068] Example 3

[0069] Reference Figure 7 and Figure 8 , which is the third embodiment of the present invention.

[0070] In this embodiment, preferably, an electrode plate 105 is provided on the outside of the flow battery pack 100, and the electrode plate 105 is connected to the power supply 102. A cooling component 300 is provided on the outside of the electrode plate 105 to cool it. The cooling component 300 can dissipate the temperature generated by the operation of the electrode plate 105, so that the electrolyte circulating inside the flow battery pack 100 is maintained at a suitable temperature, thereby reducing the impact of high temperature on the test results of the ion exchange membrane 101. The cooling component 300 includes:

[0071] An insulating shell 301 is installed on the outer surface of the electrode plate 105. The insulating shell 301 is a hollow rectangular three-dimensional structure with an open side. A cooling coil 302 is provided inside the insulating shell 301 and is in contact with the outer side of the electrode plate 105. The lower end of the cooling coil 302 is connected to the external cooling water system. The cooling coil 302 fills the space of the insulating shell 301 and increases the contact area with the electrode plate 105, so as to fully cool and dissipate heat from the inner space of the insulating shell 301 and the surface of the electrode plate 105.

[0072] The cooling coil 303 is located outside the refrigeration coil 302. The overall temperature of the cooling coil 303 is lower due to the influence of the internal space of the insulation shell 301. Before the electrolyte flows back to the liquid storage tank 103, it will flow through the cooling coil 303 for cooling and heat dissipation. A drainage pipe 304 is provided between one end of the cooling coil 303 and the top of the liquid flow battery pack 100, and a connecting water pipe 305 is provided between the other end of the cooling coil 303 and the liquid storage tank 103 to facilitate the electrolyte to flow back through the cooling coil 303.

[0073] In this embodiment, preferably, a horizontal plate 307 is horizontally arranged inside the heat-insulating shell 301. The horizontal plate 307 can not only support the cooling coil 303 and the refrigeration coil 302, but also drive the adsorption sleeve 308 to move up and down to adsorb water droplets condensed on the surface. An electric telescopic rod 306 is arranged on the upper surface of the heat-insulating shell 301. The telescopic rod arranged inside the electric telescopic rod 306 is fixed on the upper surface of the horizontal plate 307, which is convenient for driving the horizontal plate 307 to move up and down, and convenient for adsorption and drying of the tube body surface. The upper surface of the horizontal plate 307 is provided with an adsorption sleeve 308 mounted on the refrigeration coil 302, and the inner wall of the heat-insulating shell 301 is provided with a guide rod 309 that is movable through the end of the horizontal plate 307 to guide the horizontal plate 307.

[0074] In summary, when in use, the cooling water system flows the cooling water through the refrigeration coil 302, fully flows and adheres to the surface of the electrode plate 105, transfers the low temperature to the surface of the electrode plate 105, cools the electrode plate 105, and reduces the high temperature generated when the electrode plate 105 is energized. At the same time, the internal space of the thermal insulation shell 301 is filled with cooling, and the cooling coil 303 located in the thermal insulation shell 301 is cooled, so that the electrolyte enters the cooling coil 303 through the drain pipe 304 for cooling and heat dissipation. The electrolyte after heat dissipation enters the liquid storage tank 103 for collection through the connecting water pipe 305, which facilitates the electrolyte circulation and re-enters the liquid flow battery pack 100 for testing, reducing the impact of higher temperature on the use of the electrolyte.

[0075] Example 4

[0076] Combining the structures of Example 1, Example 2, and Example 3, a method for testing the oxidation resistance of a flow battery membrane in this embodiment is obtained, comprising the following steps:

[0077] S1. Prepare a certain amount of 1.5M VOSO4 and H2SO4 electrolyte with different concentrations, preferably 2-3M;

[0078] S2. Inject the electrolyte prepared in step 1 into the vanadium flow battery pack 100. The volume of the positive electrode electrolyte is twice that of the negative electrode. Then charge the battery continuously to a density of 80-160 mA / cm 2 Preferably 120 mA / cm 2 ;

[0079] S3, the VO2 prepared at the positive electrode in step 2 + H2SO4 solution, detected by UV spectrophotometer, VO 2+ The concentration was lower than the detection limit of UV-visible spectrophotometer, indicating that VO 2+ Completely converted into VO2 + ;

[0080] S4, assembling the flow battery group 100 to be tested, with the ion exchange membrane 101 to be tested in the middle, and the thickness of the ion membrane is 50 microns or 60 microns;

[0081] S5. Connect the two sides of the assembled liquid flow battery pack 100 to the circulation pump 104 respectively, and connect the same liquid flow battery pack 100 at the same time, and inject a certain volume of VO2 into the liquid flow battery pack 100. + The test solution is circulated to both sides of the test fixture by the circulation pump 104. Before the electrolyte enters the flow battery pack 100, the flow rate and flow rate are regulated by the flow control device 200 to maintain an appropriate flow rate of the electrolyte and reduce the adverse effects of the flow rate on the ion exchange membrane test;

[0082] S6. Take part of the solution in the liquid storage tank 103 and test VO at different test times. 2+ If the solution contains VO 2+ , indicating that the ion exchange membrane 101 is VO2 + Oxidation, local degradation has occurred, VO 2+ The higher the concentration, the worse the oxidation resistance of the membrane.

[0083] Following the above steps, the test solution in the storage tank was taken on the first, seventh, fourteenth, and thirtieth days respectively. The absorbance at a wavelength of about 765 nm was measured by ultraviolet spectrophotometer. Based on the relationship between absorbance and concentration, the VO2 in the test solution was obtained. 2+ concentration.

[0084] The comparative example is that the ion proton exchange membrane is immersed in the prepared 140mL1.5M VO2 + , 3MH2SO4 solution, and the test volume of the solution in the comparative example and the present application is the same.

[0085] Table 1 Test results of the embodiments and comparative examples

[0086]

[0087] As shown in Table 1, the test data of the embodiment is significantly more stable than that of the comparative example, showing a steady upward trend. The test data is not a single set, but rather a set of data selected for comparison after multiple tests. The test results of the present invention show a more pronounced concentration change trend than the comparative example, avoiding the comparative example's testing method's failure to account for electrolyte flow in actual applications and also avoiding the impact of local concentration changes caused by immersion in the electrolyte.

[0088] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A device for testing the oxidation resistance of a flow battery membrane, characterized in that: include: A liquid flow battery pack (100), wherein an ion exchange membrane (101) is embedded in the liquid flow battery pack (100); A liquid storage tank (103) is installed behind the liquid flow battery pack (100), and a circulation pump (104) for circulating electrolyte is provided between the liquid storage tank (103) and both sides of the liquid flow battery pack (100); A flow control device (200) for controlling the flow rate of an electrolyte, installed between a circulation pump (104) and a flow battery pack (100), the flow control device (200) comprising a flow box (201) for storing the electrolyte, a bubble elimination component (202) for eliminating bubbles in the electrolyte in the flow box (201), and a control component (203) for controlling the flow rate of the electrolyte; An electrode plate (105) is provided on the outside of the flow battery pack (100), and a cooling component (300) for cooling the electrode plate (105) is provided on the outside of the electrode plate (105). The cooling component (300) includes: A heat-insulating shell (301) is installed on the outer surface of the electrode plate (105), and a refrigeration coil (302) is provided inside the heat-insulating shell (301) and is in contact with the outer surface of the electrode plate (105); A cooling coil (303) is located outside the refrigeration coil (302), a drainage pipe (304) is provided between one end of the cooling coil (303) and the top of the flow battery pack (100), and a connecting water pipe (305) is provided between the other end of the cooling coil (303) and the liquid storage tank (103); A horizontal plate (307) is horizontally arranged inside the heat-insulating shell (301), an electric telescopic rod (306) is arranged on the upper surface of the heat-insulating shell (301), and a telescopic rod arranged inside the electric telescopic rod (306) is fixed to the upper surface of the horizontal plate (307); The upper surface of the transverse plate (307) is provided with an adsorption sleeve (308) sleeved on the refrigeration coil (302), and the inner wall of the heat-insulating shell (301) is provided with a guide rod (309) that movably passes through the end of the transverse plate (307).

2. The device for testing the oxidation resistance of a flow battery membrane according to claim 1, characterized in that: A shallow water chamber (2012) and a deep water chamber (2011) are provided inside the flow box (201), and the bubble elimination component (202) and the regulating component (203) are respectively located in the shallow water chamber (2012) and the deep water chamber (2011).

3. The device for testing the oxidation resistance of a flow battery membrane according to claim 2, characterized in that: The regulating component (203) for regulating the liquid flow distance from the inner wall of the deep water chamber (2011) includes: A front regulating buffer plate (2031) and a rear regulating buffer plate (2032) are staggeredly installed on the front and rear inner walls of the deep water chamber (2011), wherein the upper surfaces of the outer ends of the front regulating buffer plate (2031) and the rear regulating buffer plate (2032) pass through the flow box (201) and are exposed to the outside; A front rotating rod (2034) and a rear rotating rod (2035) mounted on the upper surface of the flow box (201) and configured to change the angle of the rotating shaft (2033); A lower bevel gear (2036) sleeved on the rotating shaft (2033) and an upper bevel gear (2037) sleeved on the front rotating rod (2034) and meshing with the lower bevel gear (2036).

4. The device for testing the oxidation resistance of a flow battery membrane according to claim 3, characterized in that: A hand wheel is provided at one end of the front rotating rod (2034), and a stable seat supporting the front rotating rod (2034) and the rear rotating rod (2035) is provided on the upper surface of the flow box (201).

5. The device for testing the oxidation resistance of a flow battery membrane according to claim 3, characterized in that: The bubble elimination member (202) installed in the shallow water chamber (2012) for eliminating bubbles comprises: two mounting shafts (221) rotatably mounted inside the shallow water chamber (2012); A plurality of bubble elimination rods (222) are circumferentially mounted on the mounting shaft (221); and a driving motor (2023) mounted on the upper end of one of the mounting shafts (2021).

6. The device for testing the oxidation resistance of a flow battery membrane according to claim 3, characterized in that: A synchronization component (206) is provided between the front rotating rod (2034) and the rear rotating rod (2035), and the synchronization component (206) comprises a lower rack (2061) vertically located below the front rotating rod (2034) and the rear rotating rod (2035), and a fixed gear (2062) meshing with the lower rack (2061) is sleeved on the front rotating rod (2034) and the rear rotating rod (2035).

7. A method for testing the oxidation resistance of flow battery membranes, characterized in that: The device for testing the oxidation resistance of a flow battery membrane according to any one of claims 1 to 6 comprises the following steps: S1. Prepare a certain amount of 1.5M VOSO4 and H2SO4 electrolyte with different concentrations; S2. Inject the electrolyte prepared in step 1 into the vanadium flow battery pack (100). The volume of the positive electrode electrolyte is twice that of the negative electrode. Then, charge the battery continuously. The electric density is 80-160 mA / cm 2 ; S3, the VO2 prepared at the positive electrode in step S2 + H2SO4 solution, detected by UV spectrophotometer, VO 2+ The concentration was lower than the detection limit of UV-visible spectrophotometer, indicating that VO 2+ Completely converted into VO2 + ; S4, assembling the flow battery group (100) to be tested, with the ion exchange membrane (101) to be tested in the middle, and the thickness of the ion membrane is 50 microns or 60 microns; S5. Connect the two sides of the assembled liquid flow battery pack (100) to the circulation pump (104) respectively, and connect the same liquid flow battery pack (100) at the same time, and inject a certain volume of VO2 into the liquid flow battery pack (100). + The test solution is circulated to both sides of the test fixture by a circulation pump (104); S6. Take part of the solution in the liquid storage tank (103) at different test times to test VO 2+ If the solution contains VO 2+ , indicating that the ion exchange membrane (101) was VO2 + Oxidation, local degradation has occurred, VO 2+ The higher the concentration, the worse the oxidation resistance of the membrane.

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