A method and device for testing ion selectivity of flow battery

Abstract

The invention discloses a method and device for testing ion selectivity of a flow battery, and relates to the technical field of flow battery testing. The method and device comprise a base, a front half tank box and a rear half tank box, wherein a diaphragm is arranged between the front half tank box and the rear half tank box. The invention combines a designed test tank with a mixing mechanism, wherein during use, a plurality of test tanks can be used to place solutions of different concentrations, and the solutions of different concentrations can be tested, so that the selectivity of ions can be tested and evaluated more comprehensively. During mixing, a main stirring rack drives the solution to flow in one direction, and two groups of supporting stirring racks rotate in the opposite direction of the main stirring rack, driving the solution to flow in different directions, so that the solution can be mixed evenly. By stirring and mixing the solution in the front half tank box, the generated concentrated water layer is reduced, thereby reducing the amount of the concentrated water layer attached to the surface of the diaphragm, and increasing the test effect and result.

Description

Technical Field

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

[0002] Liquid flow batteries are composed of battery stack units, electrolytes, electrolyte storage and supply units, and management and control units. They use positive and negative electrolytes to separate and circulate separately. They have the characteristics of high capacity, wide application range, and long cycle life. The ion selective concentration permeation test of liquid flow batteries is based on the permeation phenomenon of ions under the action of concentration gradient. When there is a concentration difference between the solutions on both sides, ions will penetrate from the high concentration side to the low concentration side through the diaphragm. By measuring the concentration change of ions on the permeation side, the permeation rate and selectivity coefficient of the ions can be calculated. By analyzing the test results, the barrier capacity and selectivity of the diaphragm for ions can be understood. If the permeation rate is low and the selectivity coefficient is high, it means that the diaphragm has a good barrier effect on ions and good selectivity; conversely, if the permeation rate is high and the selectivity coefficient is low, it means that the diaphragm has a poor barrier effect on ions and poor selectivity. This helps to provide an important basis for the design and optimization of liquid flow batteries.

[0003] In the prior art, an electrolyte of a certain concentration is placed in the front half tank box on one side of the diaphragm, and a blank liquid of the same volume as the electrolyte is poured into the back half tank on the other side of the diaphragm. The blank liquid is deionized water or a magnesium sulfate solution. During the test, the high-concentration ions in the electrolyte penetrate through the diaphragm into the low-concentration deionized water or magnesium sulfate solution. The ions penetrate through the diaphragm from the high-concentration side to the low-concentration side. By measuring the concentration change of the ions on the permeation side, the permeation rate and selectivity coefficient of the ions are calculated. However, during the test, the high-concentration ions in the electrolyte are easily retained on the surface of the diaphragm when passing through the diaphragm, forming a concentrated water layer with a high concentration. The layer adheres to the surface of the diaphragm, which is called concentration polarization. Concentration polarization will cause the concentration on the surface of the diaphragm to be higher than the concentration in the main body of the solution, thereby increasing the osmotic pressure and affecting the permeation flux of the solvent. Although the traditional method is to reduce the concentration polarization by rotating the stirring bar in the two half-tanks in the magnetic stirrer, the stirring force on the solution close to the wall and bottom of the half-tank when the stirring bar rotates in the half-tank is relatively weak, and the solution at the edge is prone to slow flow and insufficient mixing, which affects the stirring and mixing effect of the solution, thereby affecting the test effect and the accuracy of the results. For this reason, we propose a method and device for testing the ion selectivity of flow batteries. Summary of the invention

[0004] The object of the present invention is to provide a method and device for testing ion selectivity of a flow battery to solve the technical problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a flow battery ion selectivity test device, comprising a base, a front half tank box and a rear half tank box, a diaphragm is arranged between the front half tank box and the rear half tank box, three groups of test tanks are opened on the base, and a mixing mechanism for mixing the solutions in the front half tank box and the rear half tank box is arranged on the base, and the mixing mechanism comprises:

[0006] The auxiliary stirring assembly is arranged inside the front half tank box and the rear half tank box, and is used to fully stir and mix the solution;

[0007] A main stirring assembly is arranged above the base and is used to stir and mix the solution;

[0008] The main stirring assembly includes a rotatable main stirring frame and two groups of supporting stirring frames. The two groups of supporting stirring frames are both sleeved with outer wheels fixed on the outside, a second transmission belt is sleeved between the two groups of outer wheels, a rotating wheel is sleeved and fixed on the top of the main stirring frame, and bearing frames are provided on the two groups of supporting stirring frames, and intermediate wheels are rotatably provided on the bearing frames.

[0009] Preferably, the main stirring assembly also includes a bracket fixed on the top of the base, two groups of long worm gears are rotatably arranged inside the bracket, a worm gear is fixed on the top of the stirring frame, a reduction motor is fixed on the bracket, and a first transmission belt is sleeved between the ends of the two groups of long worm gears.

[0010] Preferably, the auxiliary stirring assembly includes a cylinder fixed at the bottom of the inner wall of the front half trough box and the rear half trough box and a rotatable protrusion, a lifting stirring blade is slidably arranged inside the cylinder, a connecting spring is fixedly arranged between the bottom of the lifting stirring blade and the bottom of the inner wall of the cylinder, and a sphere is fixedly arranged on the top of the lifting stirring blade.

[0011] Preferably, a plurality of blades are fixedly provided on the outside of the boss, main conical teeth are fixedly provided on the side of the boss, first conical teeth are fixedly provided on the outside of the main stirring frame, and a concave rod is provided between the cylinder and the boss.

[0012] Preferably, a sweeping piece is provided inside the front half trough box, and the sweeping piece includes a brush handle located at the top of the front half trough box and a screw rod rotatably arranged at the bottom of the inner wall of the front half trough box, a nut seat is arranged outside the screw rod, and a plurality of groups of breaking plates are fixedly arranged on the inner wall of the brush handle.

[0013] Preferably, a first rotating wheel is sleeved and fixed on the outside of the supporting stirring frame, a second rotating wheel is sleeved and fixed on the top of the screw rod, and a third transmission belt is sleeved between the first rotating wheel and the second rotating wheel.

[0014] Preferably, the front half trough box and the rear half trough box are both provided with a disturbance member inside, and the disturbance member includes two groups of vertical pipes and auxiliary conical teeth.

[0015] Preferably, an eccentric rod is fixedly provided on one side of the secondary conical tooth, two sets of rotating rings are rotatably provided outside the eccentric rod, a first vertical rod is fixedly provided at the bottom of the rotating ring, a piston is slidably provided inside the vertical tube, and a vertical plate is fixedly provided on the top of the piston.

[0016] Preferably, a mounting frame is fixedly provided at the bottom of the bearing frame, the vertical pipe is fixed on the mounting frame, and the auxiliary conical gear is rotatably provided on the mounting frame.

[0017] The present invention also discloses a method for testing ion selectivity of a flow battery, comprising the following steps:

[0018] S1. Prepare electrolyte and blank solution of different concentrations according to test requirements;

[0019] S2, fix the diaphragm between the front half tank box and the rear half tank box in the test device, then pour the electrolyte into the front half tank box, and pour the blank solution into the rear half tank box;

[0020] S3, turning on the reduction motor, stirring and mixing the solutions in the front half tank box and the rear half tank box through the main stirring component and the auxiliary stirring component;

[0021] S4, sweeping away the concentrated water layer trapped on the surface of the diaphragm and attached to the inner wall surface of the front half tank box by means of a sweeping member;

[0022] S5, disturbing the solutions in the front half tank box and the rear half tank box by means of a disturbing member;

[0023] S6. Take samples from the blank solution at regular intervals using a pH meter and an ultraviolet spectrophotometer to measure the pH value and absorbance thereof;

[0024] S7. Based on the measured pH value and absorbance data, calculate the concentration of ions entering the blank solution, obtain the rate of change of ion concentration in the blank solution with time through linear fitting, and calculate the selectivity coefficient of the membrane for ions according to the Fick diffusion formula.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention combines the designed test slots and mixing mechanisms. During use, multiple test slots can be used to place solutions of different concentrations. Solutions of different concentrations can be tested, and the selectivity of ions can be tested and evaluated more comprehensively. During mixing, the main stirring rack drives the solution to flow in one direction, and the two sets of supporting stirring racks rotate in the opposite direction of the main stirring rack, driving the solution to flow in different directions, so that the solutions can be mixed evenly. By stirring and mixing the solution in the front half of the slot box, the generated concentrated water layer is reduced, thereby reducing the amount of concentrated water layer attached to the surface of the diaphragm. At the same time, by stirring and mixing, the ions in the electrolyte can quickly diffuse into the blank solution, so that the ions are quickly and evenly distributed in the entire blank solution, which is convenient for measuring the concentration of ions in the blank solution and increasing the test effect and results.

[0027] (2) The present invention has a designed sweeping piece. When a portion of concentrated water layer is attached to the surface of the diaphragm facing the front half tank box during use, the brush handle is moved up and down to sweep away the attached concentrated water layer, thereby further reducing the amount of attached concentrated water layer and improving the smoothness of ions passing through the diaphragm in the front half tank box, thereby improving the test effect and the accuracy of the results.

[0028] (3) The present invention uses a designed disturbance piece, which drives the solution to be sucked in or squeezed out by moving the piston up and down in the vertical tube during use. The solution sucked into the vertical tube has a certain speed and force when being squeezed into the front half tank box and the rear half tank box, which will impact the solution in the front half tank box and the rear half tank box, triggering the flow and disturbance of the solution, so that the internal solution forms a flow in different directions, thereby increasing the stirring and mixing effect of the solution, further improving the stirring and mixing effect of the solution, and further improving the test effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the present invention;

[0030] Figure 2 It is a rear view structural schematic diagram of the rear half tank box of the present invention;

[0031] Figure 3 It is a schematic diagram of the front half slot box and the long worm structure of the present invention;

[0032] Figure 4 It is a schematic diagram of the side view structure of the vertical pipe and the auxiliary conical teeth of the present invention;

[0033] Figure 5 It is a schematic diagram of the structure of the main stirring frame and the supporting stirring frame of the present invention;

[0034] Figure 6 It is a structural schematic diagram of the bearing frame of the present invention;

[0035] Figure 7 It is a schematic diagram of the brush handle structure of the present invention;

[0036] Figure 8 It is a schematic diagram of the structure of the first vertical rod and the second vertical rod of the present invention;

[0037] Fig. 9 It is a schematic diagram of the structure of the convex column and the lifting stirring blade of the present invention;

[0038] Fig.10 It is a schematic diagram of the cross-sectional structure of the cylinder of the present invention;

[0039] Fig.11 It is a schematic diagram of the diaphragm structure of the present invention;

[0040] In the figure: 100, base; 101, front half tank box; 102, rear half tank box; 103, diaphragm; 200, test tank; 201, long worm; 202, bracket; 203, first transmission belt; 204, stirring support; 205, worm wheel; 206, main stirring frame; 207, cylinder; 208, first conical tooth; 209, outer wheel; 210, second transmission belt; 211, boss; 212, rotating wheel; 213, bearing frame; 214, bearing frame; 215, bearing frame; 216, bearing frame; 217, bearing frame; 218, bearing frame; 219, bearing frame; 220, bearing frame; 221, bearing frame; 222, bearing frame; 223, bearing frame; 224, bearing frame; 225, bearing frame; 226, bearing frame; 227, bearing frame; 228, bearing frame; 229, bearing frame; 230, bearing frame; 231, bearing frame; 232, bearing frame; 233, bearing frame; 234, bearing frame; 235, bearing frame; 236, bearing frame; 237, bearing frame; 238, bearing frame; 239, bearing frame; 240, bearing frame; 241, bearing frame; 242, bearing frame; 243, bearing frame; 244, bearing frame; 245, bearing frame; 246, bearing frame; 247, bearing frame; 248, bearing frame; 249, bearing frame; 250, bearing frame; 251, bearing frame; 252, bearing frame; 253, bearing frame; 254, bearing frame; 255, bearing frame; 256, bearing frame; 257, bearing frame; 4. Intermediate wheel; 216. Blade; 217. Lifting stirring blade; 218. Concave rod; 219. Connecting spring; 220. Conveyor belt; 300. Screw; 301. Brush handle; 302. Third transmission belt; 303. Breaking plate; 304. Nut seat; 400. Vertical tube; 401. Secondary conical teeth; 402. Eccentric rod; 404. Mounting frame; 405. First vertical rod; 406. Vertical plate; 407. Piston; 408. Rotating ring. DETAILED DESCRIPTION

[0041] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0042] Embodiment 1

[0043] See also Figure 1-Figure 11 The present invention provides a technical solution: a method for testing ion selectivity of a flow battery, comprising the following steps:

[0044] S1. Prepare electrolyte and blank solution of different concentrations according to test requirements;

[0045] S2, fix the diaphragm 103 between the front half tank box 101 and the rear half tank box 102 in the test device, then pour the electrolyte into the front half tank box 101, and pour the blank solution into the rear half tank box 102;

[0046] S3, turning on the reduction motor, stirring and mixing the solutions in the front half tank box 101 and the rear half tank box 102 through the main stirring assembly and the auxiliary stirring assembly;

[0047] S4, using a cleaning member to clean up the concentrated water layer trapped on the surface of the diaphragm 103 and attached to the inner wall surface of the front half tank box 101;

[0048] S5, disturbing the solutions in the front half tank box 101 and the rear half tank box 102 by means of a disturbance element;

[0049] S6. Take samples from the blank solution at regular intervals using a pH meter and an ultraviolet spectrophotometer to measure the pH value and absorbance thereof;

[0050] S7. According to the measured pH value and absorbance data, the concentration of ions entering the blank solution is calculated, and the rate of change of the ion concentration in the blank solution with time is obtained by linear fitting. The selectivity coefficient of the ion of the membrane 103 is calculated according to the Fick diffusion formula. The barrier capacity and selectivity of the membrane 103 for ions can be understood through the test results. If the permeation rate is low and the selectivity coefficient is high, it means that the membrane 103 has a good barrier effect and good selectivity for ions; conversely, if the permeation rate is high and the selectivity coefficient is low, it means that the barrier effect and selectivity of the membrane 103 for ions are poor;

[0051] The test chamber comprises a base 100, a front half tank box 101 and a rear half tank box 102. The bottoms of the front half tank box 101 and the rear half tank box 102 are both provided with drain pipes, and the ends of the drain pipes extend to the outside of the bottom of the base 100. A valve is provided on the drain pipe, and the solution can be discharged outward through the drain pipe after the test is completed. A diaphragm 103 is provided between the front half tank box 101 and the rear half tank box 102. Three groups of test tanks 200 are provided on the base 100. A low-concentration solution is placed in the first group of test tanks 200, a medium-concentration solution is placed in the second group of test tanks 200, and a high-concentration solution is placed in the third group of test tanks 200. Solutions of different concentrations are tested to more comprehensively test and evaluate the selectivity of ions. A mixing mechanism for mixing the solutions in the front half tank box 101 and the rear half tank box 102 is provided on the base 100. The mixing mechanism comprises an auxiliary stirring component and a main stirring component.

[0052] The main stirring assembly includes a main stirring frame 206 and two groups of supporting stirring frames 204, the two groups of supporting stirring frames 204 are both sleeved with outer wheels 209, a second transmission belt 210 is sleeved between the two groups of outer wheels 209, a rotating wheel 212 is sleeved and fixed on the top of the main stirring frame 206, a bearing frame 213 is provided on the two groups of supporting stirring frames 204, an intermediate wheel 214 is rotatably provided on the bearing frame 213, and a conveyor belt 220 is sleeved between the rotating wheel 212 and the intermediate wheel 214;

[0053] The main stirring assembly also includes a bracket 202 fixed on the top of the base 100, and two groups of long worms 201 are rotatably arranged inside the bracket 202. One group of long worms 201 can drive multiple groups of worm gears 205 to rotate. A worm gear 205 is fixed on the top of the supporting stirring frame 204, and the worm gear 205 is meshed with the long worm 201. A reduction motor is fixed on the bracket 202, and the reduction motor drives the supporting stirring frame 204 and the main stirring frame 206 to rotate forward or reversely, and drives the brush handle 301, the lifting stirring blade 217 and the piston 407 to move up and down. The shear force and impact force generated at different heights can make the ions in the solutions at different heights mix with each other, thereby increasing the stirring and mixing degree of the solution. The working end of the reduction motor extends to the end of the long worm 201, and a first transmission belt 203 is sleeved between the ends of the two groups of long worms 201.

[0054] Embodiment 2

[0055] Based on Example 1, please refer to Figure 2 , Figure 3 , Figure 4 , Fig. 9 and Fig.10 The auxiliary stirring assembly includes a cylinder 207 fixed to the bottom of the inner wall of the front half tank box 101 and the rear half tank box 102 and a rotatably arranged boss 211. A lifting stirring blade 217 is slidably arranged inside the cylinder 207. The lifting stirring blade 217 can move up and down. A connecting spring 219 is fixedly arranged between the bottom of the lifting stirring blade 217 and the bottom of the inner wall of the cylinder 207. A ball is fixedly arranged on the top of the lifting stirring blade 217. The ball makes it easy for the ball and the lifting stirring blade 217 at the bottom to move up and down smoothly when in contact with the boss 211 above.

[0056] The outside of the protruding column 211 is fixedly provided with multiple sets of blades 216. When the protruding column 211 is rotating, it can also drive the multiple sets of blades 216 outside to rotate. At this time, the blades 216 and the protruding part of the protruding column 211 outside have a stirring effect on the solution again, further increasing the stirring effect of the solution. The side of the protruding column 211 is fixedly provided with a main conical tooth, and the outside of the main stirring frame 206 is sleeved and fixed with a first conical tooth 208, which is meshed with the main conical tooth. A concave rod 218 is provided between the cylinder 207 and the protruding column 211, and the protruding column 211 is rotatably provided on the top of the concave rod 218.

[0057] The top of the sphere contacts the outer wall of the protruding column 211 , and the front half slot box 101 and the rear half slot box 102 are both located inside the test slot 200 .

[0058] The present invention combines the designed test slots 200 with the mixing mechanism. During use, multiple test slots 200 can be used to place solutions of different concentrations, and the solutions of different concentrations can be tested, so that the selectivity of ions can be tested and evaluated more comprehensively. During mixing, the main stirring rack 206 drives the solution to flow in one direction, and the two sets of supporting stirring racks 204 rotate in the opposite direction of the main stirring rack 206, driving the solution to flow in different directions, so that the solutions can be mixed evenly. By stirring and mixing the solution in the front half slot box 101, the generated concentrated water layer is reduced, and then the amount of concentrated water layer attached to the surface of the diaphragm 103 is reduced. At the same time, by stirring and mixing, the ions in the electrolyte can quickly diffuse after entering the blank solution, so that the ions are quickly and evenly distributed in the entire blank solution, which is convenient for measuring the concentration of ions in the blank solution and increasing the test effect and results.

[0059] In summary, the diaphragm 103 is installed between the front half tank box 101 and the back half tank box 102, and then the electrolyte and blank solution of different concentrations are poured into the corresponding front half tank box 101 and the back half tank box 102 respectively, and then the reduction motor is turned on to drive the two groups of long worms 201 to rotate, drive the multiple groups of worm gears 205 to rotate, and drive the support stirring frame 204 to rotate through the worm gears 205. When the support stirring frame 204 rotates, the outer wheel 209 is driven to rotate, and the outer wheel 209 is driven to rotate through the second transmission belt 210 to drive another group of support stirring frames 204 to rotate. At this time, the two groups of support stirring frames 204 rotate to drive the solution. The liquid flows in one direction, and the second transmission belt 210 rotates while driving the conveyor belt 220 in contact with it to rotate in the opposite direction to the supporting stirring frame 204, thereby driving the intermediate wheel 214 and the rotating wheel 212 to rotate in the opposite direction to the supporting stirring frame 204 through the conveyor belt 220, thereby driving the main stirring frame 206 to rotate in the opposite direction to the supporting stirring frame 204. At this time, the main stirring frame 206 drives the solution that is driven by the supporting stirring frame 204 to flow in one direction to break up the solution, thereby increasing the uniformity of mixing. At the same time, when the main stirring frame 206 rotates, it drives the first conical gear 2 08 rotates, thereby driving the main conical teeth meshing therewith to rotate, and the main conical teeth drive the boss 211 to rotate, and then the protruding part of the outer surface of the boss 211 contacts the top ball of the lower lifting stirring blade 217, and the ball is squeezed by the upper lifting stirring blade 217 and begins to move downward. At this time, the bottom of the lifting stirring blade 217 slides downward in the cylinder 207, and the connecting spring 219 is squeezed by the bottom of the upper lifting stirring blade 217 and begins to compress, and then when the protruding part of the boss 211 is no longer in contact with the lower ball, the connecting spring 219 resets, pushing the upper lifting stirring blade 217 to move downward. The descending stirring blade 217 moves upward, and at this time, the bottom of the lifting stirring blade 217 moves upward inside the cylinder 207, driving the ball to move, and repeating this process. The solution can be stirred in the up and down directions by the lifting stirring blade 217 that moves up and down. The lifting stirring blade 217 can cover solutions at different heights in the front half tank box 101 and the back half tank box 102. The shear force and impact force generated by the up and down movement of the lifting stirring blade 217 at different heights can make the ions in the solutions at different heights mix with each other, so that the entire solution can be fully stirred, thereby improving the uniformity of stirring.

[0060] Embodiment 3

[0061] Based on Example 2, please refer to Figure 1-Figure 7, a cleaning member is arranged inside the front half tank box 101, and the cleaning member includes a brush handle 301 located at the top of the front half tank box 101 and a screw rod 300 rotatably arranged at the bottom of the inner wall of the front half tank box 101. The brush handle 301 reciprocates up and down to clean the concentrated water layer attached to the surface of the diaphragm 103, and can also clean some concentrated water layers attached to the inner wall of the front half tank box 101 to reduce adhesion. A nut seat 304 is arranged outside the screw rod 300, and the brush handle 301 is fixed on the nut seat 304. A plurality of groups of breaking plates 303 are fixedly arranged on the inner wall of the brush handle 301. When the solution in the front half tank box 101 and the rear half tank box 102 hits the breaking plates 303 on the brush handle 301 that moves up and down during the stirring flow process, the breaking plates 303 break up the flowing solution to improve the mixing uniformity;

[0062] A first rotating wheel is sleeved and fixed on the outside of the stirring frame 204 , a second rotating wheel is sleeved and fixed on the top of the screw rod 300 , and a third transmission belt 302 is sleeved between the first rotating wheel and the second rotating wheel.

[0063] The present invention has a designed sweeping piece. When a part of the concentrated water layer is attached to the surface of the diaphragm 103 facing the front half tank box 101 during use, the brush handle 301 is moved up and down to sweep away the attached concentrated water layer, thereby further reducing the amount of attached concentrated water layer and improving the smoothness of ions passing through the diaphragm 103 in the front half tank box 101, thereby improving the test effect and the accuracy of the results.

[0064] In summary, when the supporting stirring frame 204 rotates, it drives the first rotating wheel mounted on the supporting stirring frame 204 to rotate, and the first rotating wheel drives the second transmission belt 210 mounted on the screw rod 300 to rotate through the third transmission belt 302, thereby driving the screw rod 300 to rotate, and the screw rod 300 drives the external nut seat 304 to move downward, and drives the brush handle 301 to move downward through the nut seat 304. At this time, the brush handle 301 sweeps away the concentrated water layer attached to the surface of the diaphragm 103, reducing the amount of attachment on the surface of the diaphragm 103. At the same time, when the brush handle 301 descends, it can also sweep away some of the concentrated water layer attached to the inner wall of the front half tank box 101, thereby increasing the sweeping effect. When the nut seat 304 moves downward to a suitable position, the reduction motor is reversed to drive the nut seat 304 and the brush handle 301 to move upward, and this is repeated. At the same time, it will also drive the supporting stirring frame 204 and the main stirring frame 206 to rotate in the opposite direction of the previous rotation, thereby increasing the stirring and mixing effect of the solution again.

[0065] Embodiment 4

[0066] Based on Example 3, please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 8The front half tank box 101 and the rear half tank box 102 are both provided with a disturbance member, the disturbance member includes two sets of vertical pipes 400 and auxiliary conical teeth 401, and the auxiliary conical teeth 401 are meshed with the first conical teeth 208;

[0067] An eccentric rod 402 is fixedly provided on one side of the secondary conical tooth 401, and two sets of rotating rings 408 are rotatably provided on the outside of the eccentric rod 402. A first vertical rod 405 is fixedly provided on the bottom of the rotating ring 408. A piston 407 is slidably provided inside the vertical tube 400. The piston 407 moves up and down to suck the solution into or squeeze it out of the vertical tube 400. A vertical plate 406 is fixedly provided on the top of the piston 407. The vertical plate 406 is rotatably connected to the first vertical rod 405 through a rotating shaft. The rotating shaft facilitates the vertical plate 406 below to move up and down stably and vertically through the rotating shaft when the first vertical rod 405 moves up and down with the rotating ring 408 to generate rotation;

[0068] A mounting frame 404 is fixedly provided at the bottom of the bearing frame 213 , the vertical pipe 400 is fixed on the mounting frame 404 , and the secondary conical gear 401 is rotatably provided on the mounting frame 404 .

[0069] The present invention uses a designed disturbance piece, which drives the solution to be sucked in or squeezed out by moving the piston 407 up and down in the vertical tube 400 during use. The solution sucked into the vertical tube 400 has a certain speed and force when being squeezed into the front half tank box 101 and the rear half tank box 102, which will impact the solution in the front half tank box 101 and the rear half tank box 102, triggering the flow and disturbance of the solution, so that the internal solution forms a flow in different directions, thereby increasing the stirring and mixing effect of the solution, further improving the stirring and mixing effect of the solution, and further improving the test effect.

[0070] In summary, when the first conical teeth 208 rotate, the secondary conical teeth 401 are also driven to rotate. At this time, the rotating secondary conical teeth 401 drive the eccentric rod 402 on one side to rotate eccentrically, thereby driving the two sets of rotating rings 408 on the outside to move upward and downward, thereby driving the first vertical rod 405 at the bottom to move up and down, and then the first vertical rod 405 drives the vertical plate 406 and the piston 407 under the vertical plate 406 to move. At this time, the piston 407 will move up and down in the vertical tube 400. When the piston 407 moves downward, the solution will be sucked from the top of the vertical tube 400 into the inside of the vertical tube 400, and then the solution located in the vertical tube 400 will be sucked into the vertical tube 400. The solution in the tube 400 is squeezed out from the bottom of the vertical tube 400 through the piston 407. When the piston 407 moves upward, the solution is sucked into the interior of the vertical tube 400 from the bottom of the vertical tube 400, and then the solution in the vertical tube 400 is squeezed out from the top of the vertical tube 400. The solution sucked into the vertical tube 400 has a certain speed and force when it is squeezed into the front half tank box 101 and the rear half tank box 102, which will impact the solution in the front half tank box 101 and the rear half tank box 102, triggering the flow and disturbance of the solution, so that the internal solution forms a flow in different directions, thereby increasing the stirring and mixing effect of the solution.

[0071] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. 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 flow battery ion selectivity test device, characterized in that: The invention comprises a base (100), a front half tank box (101) and a rear half tank box (102), wherein a diaphragm (103) is arranged between the front half tank box (101) and the rear half tank box (102), three groups of test tanks (200) are arranged on the base (100), and a mixing mechanism for mixing solutions in the front half tank box (101) and the rear half tank box (102) is arranged on the base (100), wherein the mixing mechanism comprises: An auxiliary stirring assembly is arranged inside the front half tank box (101) and the rear half tank box (102) and is used to fully stir and mix the solution; A main stirring assembly is disposed above the base (100) and is used to stir and mix the solution; The main stirring assembly comprises a main stirring frame (206) and two groups of supporting stirring frames (204) which are rotatably arranged. The two groups of supporting stirring frames (204) are both sleeved with outer wheels (209) fixed thereto. A second transmission belt (210) is sleeved between the two groups of outer wheels (209). A rotating wheel (212) is sleeved and fixed on the top of the main stirring frame (206). The two groups of supporting stirring frames (204) are provided with bearing frames (213). An intermediate wheel (214) is rotatably arranged on the bearing frames (213). A cleaning member is arranged inside the front half trough box (101), and the cleaning member comprises a brush handle (301) located at the top of the front half trough box (101) and a screw rod (300) rotatably arranged at the bottom of the inner wall of the front half trough box (101), a nut seat (304) is arranged outside the screw rod (300), and a plurality of groups of scattering plates (303) are fixedly arranged on the inner wall of the brush handle (301).

2. A flow battery ion selectivity testing device according to claim 1, characterized in that: The main stirring assembly also includes a bracket (202) fixed on the top of the base (100), two groups of long worm gears (201) are rotatably arranged inside the bracket (202), a worm gear (205) is sleeved and fixed on the top of the supporting stirring frame (204), a reduction motor is fixedly arranged on the bracket (202), and a first transmission belt (203) is sleeved between the ends of the two groups of long worm gears (201).

3. A flow battery ion selectivity testing device according to claim 1, characterized in that: The auxiliary stirring assembly comprises a cylinder (207) fixed at the bottom of the inner wall of the front half tank box (101) and the rear half tank box (102) and a rotatably arranged protruding column (211); a lifting stirring blade (217) is slidably arranged inside the cylinder (207); a connecting spring (219) is fixedly arranged between the bottom of the lifting stirring blade (217) and the bottom of the inner wall of the cylinder (207); and a round ball is fixedly arranged at the top of the lifting stirring blade (217).

4. A flow battery ion selectivity testing device according to claim 3, characterized in that: A plurality of groups of blades (216) are fixedly arranged on the outside of the convex column (211), main conical teeth are fixedly arranged on the side of the convex column (211), a first conical tooth (208) is sleeved and fixedly arranged on the outside of the main stirring frame (206), and a concave rod (218) is arranged between the cylinder (207) and the convex column (211).

5. The liquid flow battery ion selectivity testing device according to claim 1, characterized in that: A first rotating wheel is sleeved and fixed on the outside of the supporting stirring frame (204), a second rotating wheel is sleeved and fixed on the top of the screw rod (300), and a third transmission belt (302) is sleeved between the first rotating wheel and the second rotating wheel.

6. A flow battery ion selectivity testing device according to claim 1, characterized in that: The front half tank box (101) and the rear half tank box (102) are both provided with a disturbance member inside, and the disturbance member comprises two groups of vertical pipes (400) and auxiliary conical teeth (401).

7. A flow battery ion selectivity testing device according to claim 6, characterized in that: An eccentric rod (402) is fixedly provided on one side of the secondary conical tooth (401), two sets of rotating rings (408) are rotatably provided outside the eccentric rod (402), a first vertical rod (405) is fixedly provided at the bottom of the rotating ring (408), a piston (407) is slidably provided inside the vertical tube (400), and a vertical plate (406) is fixedly provided on the top of the piston (407).

8. The liquid flow battery ion selectivity testing device according to claim 7, characterized in that: A mounting frame (404) is fixedly arranged at the bottom of the bearing frame (213), the vertical pipe (400) is fixed on the mounting frame (404), and the auxiliary conical teeth (401) are rotatably arranged on the mounting frame (404).

9. A method for testing ion selectivity of a flow battery, using the testing device according to any one of claims 1 to 8, characterized in that: The specific steps include: S1. Prepare electrolyte and blank solution of different concentrations according to test requirements; S2, fix the diaphragm (103) between the front half tank box (101) and the rear half tank box (102) in the test device, then pour the electrolyte into the front half tank box (101), and pour the blank solution into the rear half tank box (102); S3, turning on the reduction motor, stirring and mixing the solutions in the front half tank box (101) and the rear half tank box (102) through the main stirring component and the auxiliary stirring component; S4, using a cleaning member to clean up the concentrated water layer trapped on the surface of the diaphragm (103) and attached to the inner wall surface of the front half tank box (101); S5, disturbing the solutions in the front half tank box (101) and the rear half tank box (102) by means of a disturbance element; S6. Take samples from the blank solution at regular intervals using a pH meter and an ultraviolet spectrophotometer to measure the pH value and absorbance thereof; S7. Calculate the concentration of ions entering the blank solution based on the measured pH value and absorbance data, obtain the rate of change of the ion concentration in the blank solution over time through linear fitting, and calculate the selectivity coefficient of the membrane (103) for ions based on the Fick diffusion formula.

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