Bipolar plate seepage detection device for vanadium battery

Abstract

The utility model discloses a bipolar plate seepage detection device for a vanadium battery. The bipolar plate seepage detection device comprises a pair of symmetrically arranged runner frames and a fixing assembly for pressing the runner frames, runners are formed in the close end faces of the runner frames, and the fixing assembly comprises a pair of end plates abutting against the sides, away from the runners, of the runner frames; the flow channel frame is provided with a liquid inlet and a liquid outlet, the flow channel frame is respectively communicated with a liquid flowing component, and the liquid flowing component comprises a pipeline communicated with the liquid inlet and the liquid outlet, a circulating pump communicated with the pipeline and a liquid storage tank communicated with the circulating pump. According to the method, electrolyte and deionized water are respectively introduced into two sides of the bipolar plate, certain pressure and scouring are generated on the bipolar plate to be detected, the seepage process is accelerated, and meanwhile, the seepage rate can be quantitatively characterized by measuring the concentration of vanadium ions in the deionized water.

Description

Technical Field

[0001] The utility model belongs to the technical field of all-vanadium redox flow battery detection devices, and particularly relates to a liquid leakage detection device for bipolar plates of vanadium batteries. Background Art

[0002] The bipolar plate is one of the key materials of the vanadium battery stack, located at the positive and negative electrodes of a single cell respectively, and plays the role of isolating the electrolyte and supporting the electrodes. In actual operation, each single cell is usually prepared into a stack by means of lamination and fastening, forming multiple sets of sealed electrolyte positive and negative flow channels isolated by bipolar plates. When the electrolyte is introduced into the flow channels through a circulation pump, a certain pressure will be generated on the bipolar plate, and at the same time, the continuous flow of the electrolyte will scour the surface of the bipolar plate. This working environment may cause the bipolar plate to leak liquid under long-term pressure and scouring, resulting in the phenomena of cross-leakage, leakage of positive and negative electrolytes, and corrosion of copper plates, reducing the performance of the vanadium battery.

[0003] NB / T 11203-2023 Technical Conditions for Carbon-Plastic Composite Bipolar Plates for All-Vanadium Redox Flow Batteries mentions that the vanadium ion diffusion coefficient is tested according to NB / T 42080-2016. In this method, the bipolar plate is placed in two conduction cells filled with deionized water and electrolyte respectively, and the electrolyte can be scoured by the magnetic stirrers in each conduction cell, but the actual working conditions of the bipolar plate cannot be simulated.

[0004] CN 220230839 U discloses a bipolar plate airtightness testing device, which judges where there are leakage points on the bipolar plate by introducing gas on one side and observing the electrolyte bubbles on the other side. There is also a problem that the actual working conditions of the bipolar plate cannot be simulated, and the liquid leakage rate cannot be quantitatively evaluated. Summary of the Invention

[0005] In order to solve the above problems, the utility model proposes a liquid leakage detection device for bipolar plates of vanadium batteries.

[0006] A liquid leakage detection device for bipolar plates of vanadium batteries includes a pair of symmetrically arranged flow channel frames and a fixing component for pressing the flow channel frames; flow channels are arranged on the end faces of the flow channel frames close to each other, and the fixing component includes a pair of end plates that abut against the sides of the flow channel frames away from the flow channels; the flow channel frames are provided with a liquid inlet and a liquid outlet, and two flow channel frames are respectively connected with a liquid flow component, and the liquid flow component includes a pipeline connecting the liquid inlet and the liquid outlet, a circulation pump connected to the pipeline, and a liquid storage tank connected to the circulation pump.

[0007] Preferably, the depth of the flow channel is half of the thickness of the flow channel frame.

[0008] Preferably, a support block for supporting the bipolar plate to be tested is arranged in the flow channel.

[0009] Preferably, the height of the support block is equal to the depth of the flow channel.

[0010] Preferably, the length of the support block is 4 / 5 of the length of the flow channel.

[0011] Preferably, there are at least two support blocks, and a plurality of support blocks are arranged in an array along the width direction of the flow channel.

[0012] Preferably, the liquid flow assembly includes two ferrule connectors, the ferrule connectors are detachably connected to the end plate, the ferrule connectors are respectively communicated with the liquid inlet and the liquid outlet, and the pipeline is communicated with the ferrule connectors.

[0013] Preferably, the thickness of the flow channel frame is 1-3 mm.

[0014] Preferably, it further includes a plurality of seals, and the plurality of seals are respectively located between the end plate and the flow channel frame, and between the flow channel frame and the bipolar plate.

[0015] Preferably, the cross-sectional shape of the support block is rectangular.

[0016] Advantages of the present invention:

[0017] The device of the present utility model forms a closed liquid circulation loop on both sides of the bipolar plate to be tested through the arranged flow channel frame, fixing assembly, pipeline, circulation pump and liquid storage tank. Among them, electrolyte is stored in one liquid storage tank to form an electrolyte circulation loop, and deionized water is stored in the other liquid storage tank to form a deionized water loop. When the two circulation pumps respectively introduce the electrolyte and deionized water into the flow channels on both sides of the bipolar plate to be tested, the electrolyte and deionized water will continuously flush the bipolar plate to be tested, and at the same time generate a certain pressure to form the actual working condition environment of the bipolar plate, accelerating the seepage process. Using deionized water on one side, the seepage rate can be quantitatively calculated by characterizing the concentration of vanadium ions in the deionized water. In addition, the components of the seepage detection device for a bipolar plate of a vanadium battery of the present utility model are simply assembled, and the pressure and flushing degree can be adjusted by changing the power of the circulation pump. Description of the Drawings

[0018] Figure 1 is an exploded view of a seepage detection device for a bipolar plate of a vanadium battery according to the present application;

[0019] Figure 2 is a schematic diagram of the overall structure of a seepage detection device for a bipolar plate of a vanadium battery according to the present application;

[0020] Figure 3 is a top view of the flow channel frame of the present application;

[0021] Figure 4 is a bottom view of the flow channel frame of the present application.

[0022] In the figure: 1. Flow channel frame; 2. Fixed component; 3. Liquid flow component; 10. Flow channel; 11. Liquid inlet; 12. Liquid outlet; 13. Drainage area; 20. End plate; 30. Pipe; 31. Circulation pump; 32. Liquid storage tank; 33. Ferrule joint; 100. Support block. Detailed implementation manners

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Please refer to Figure 1 , a liquid leakage detection device for a bipolar plate of a vanadium battery, including a pair of symmetrically arranged flow channel frames 1, a fixed component 2 for pressing the flow channel frames 1, and a plurality of sealing films; the flow channel frame 1 is a rectangular thin plate, the thickness of the flow channel frame 1 is 1 - 3 mm, and flow channels 10 are provided on the end faces of the two flow channel frames 1 close to each other.

[0025] Please refer to Figure 4 , the projection of the flow channel 10 on the flow channel frame 1 is rectangular, drainage areas 13 are respectively communicated on both sides of the flow channel 10, the projection of the drainage area 13 on the flow channel frame 1 is also rectangular, and the depth of the flow channel 10 is half of the thickness of the flow channel frame 1.

[0026] Please refer to Figure 1 and Figure 3 , during assembly, the flow channel 10 is closely attached to the bipolar plate 4 to be tested, and the bipolar plate to be tested is clamped by the fixed component 2 and the sealing film to seal the flow channel 10. The fixed component 2 includes a pair of end plates 20 that abut against the side of the flow channel frame 1 away from the flow channel 10. A sealing film is provided between the end plate 20 and the flow channel frame 1, and a sealing film is also provided between the flow channel frame 1 and the bipolar plate 4. The end plate 20 is provided with a bolt fixing groove and a screw rod through hole. The fixed component 2 further includes a bolt passing through the bolt fixing groove and a nut screwed onto the bolt. The end plate 20 is made of metal or plastic, the flow channel frame 1 is made of polyethylene or epoxy resin, and the sealing film is made of rubber.

[0027] Refer to Figure 3 , Figure 4 , the flow channel frame 1 is provided with a liquid inlet 11 and a liquid outlet 12, and the liquid inlet 11 and the liquid outlet 12 are respectively communicated with the drainage area 13.

[0028] Please refer to Figure 2 and Figure 3, two flow channel frames 1 are respectively connected to liquid flow components 3. The liquid flow components 3 include a pipeline 30 connecting the liquid inlet 11 and the liquid outlet 12, a circulation pump 31 connected to the pipeline 30, and a liquid storage tank 32 connected to the circulation pump 31. Among them, one liquid storage tank 32 stores electrolyte, and the other liquid storage tank 32 stores deionized water. Please refer to Figure 1 , two ferrule joint connection through holes are opened at the diagonal positions of the end plate 20. The liquid flow component 3 further includes two ferrule joints 33 clamped in the ferrule joint connection through holes. Both ends of the pipeline 30 are respectively connected to the ferrule joints 33. The other end of the ferrule joint 33 away from the pipeline 33 is embedded in the liquid inlet 11 and the liquid outlet 12. The pipeline 30 is made of polytetrafluoroethylene or polyethylene.

[0029] Please refer to Figure 3 and Figure 4 , a support block 100 for supporting the bipolar plate to be tested is arranged in the flow channel 10. The cross-sectional shape of the support block 100 is a cuboid, and the height is equal to the depth of the flow channel 10. The upper end surface of the support block 100 is flush with the surface of the flow channel frame 1, and the length is 4 / 5 of the length of the flow channel 10. When it is in close contact with the bipolar plate to be tested, it can better support the bipolar plate and prevent the bipolar plate from deforming and causing damage or liquid leakage when the detection device is fastened; the number of the support blocks 100 is 5, and they are arranged in an array along the width direction of the flow channel 10.

[0030] The working principle of the present utility model:

[0031] 1. Place the bipolar plate to be tested between a pair of flow channel frames 1. The side of the flow channel frame 1 provided with the flow channel 10 is closely attached to the bipolar plate 4 to be tested, and the other side is closely attached to the end plate 20. A sealing film is arranged between the end plate 20 and the flow channel frame 1. Similarly, a sealing film is also arranged between the flow channel frame 1 and the bipolar plate 4. Each layer is sealed by the sealing film, and then the above-mentioned components are fastened by bolts and nuts. A sealed chamber is formed between the bottom wall and the side wall of the flow channel 10 and the drainage area 13 and the bipolar plate 4.

[0032] 2. Insert both ends of the pipeline 30 into the two ferrule joints 33 respectively. The two liquid storage tanks 32 store electrolyte and deionized water respectively. If the leakage direction of the bipolar plate to be tested needs to be detected, the liquid in the liquid storage tank 32 can be set according to the actual situation.

[0033] 3. During operation, the circulation pump 31 is turned on. The electrolyte and deionized water enter the closed flow channel 10 through the pipelines 30 and the liquid inlet 11 respectively, and return to the liquid storage tank 32 through the liquid outlet 12. Under the isolation of the bipolar plate to be tested, independent circulations of the electrolyte and deionized water are formed on both sides respectively; under the action of the circulation pump 31, the electrolyte and deionized water scour and apply pressure to the bipolar plate to be tested, forming the actual working condition environment of the bipolar plate. In addition, by changing the power of the circulation pump 31, the pressure and the degree of scour can be controllably adjusted; after detection at different time periods, a quantitative extraction of the deionized water in the liquid storage tank 32 is carried out for ultraviolet spectrophotometer detection, and the concentration of vanadium ions permeated at different time intervals is obtained through the absorbance parameter, and the seepage rate can be further calculated.

[0034] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "close to", "far from", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention; unless otherwise clearly specified and defined, the terms "abut", "communicate", "connect", "support" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0035] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A bipolar plate leakage detection device for a vanadium battery, comprising a pair of symmetrically arranged flow channel frames (1) and a fixing assembly (2) for pressing the two flow channel frames (1); flow channels (10) are provided on the end surfaces of the flow channel frames (1) that are close to each other, and the fixing assembly (2) comprises a pair of end plates (20) pressed against the side of the flow channel frame (1) that is away from the flow channel (10); the flow channel frame (1) is provided with a liquid inlet (11) and a liquid outlet (12), and the two flow channel frames (1) are respectively connected to a liquid flow assembly (3), and the liquid flow assembly (3) comprises a pipeline (30) connecting the liquid inlet (11) and the liquid outlet (12), a circulation pump (31) connecting the pipeline (30), and a liquid storage tank (32) connecting the circulation pump (31).

2. A bipolar plate leakage detection device for vanadium batteries according to claim 1, characterized in that: The depth of the flow channel (10) is half the thickness of the flow channel frame (1).

3. A bipolar plate leakage detection device for vanadium batteries according to claim 2, characterized in that: A support block (100) for supporting the bipolar plate (4) to be tested is arranged in the flow channel (10).

4. A bipolar plate leakage detection device for vanadium batteries according to claim 3, characterized in that: The height of the support block (100) is equal to the depth of the flow channel (10).

5. A bipolar plate leakage detection device for vanadium batteries according to claim 3, characterized in that: The length of the support block (100) is 4 / 5 of the length of the flow channel (10).

6. A bipolar plate leakage detection device for vanadium batteries according to claim 4, characterized in that: There are no less than two support blocks (100), and a plurality of the support blocks (100) are arranged in an array along the width direction of the flow channel (10).

7. A bipolar plate leakage detection device for vanadium batteries according to claim 1, characterized in that: The liquid flow component (3) comprises two ferrule joints (33), the ferrule joints (33) being detachably connected to the end plate (20), the ferrule joints (33) being respectively connected to the liquid inlet (11) and the liquid outlet (12), and the pipeline (30) being connected to the ferrule joints (33).

8. The bipolar plate leakage detection device for vanadium battery according to claim 1, characterized in that: The flow channel frame (1) has a thickness of 1 to 3 mm.

9. A bipolar plate leakage detection device for vanadium batteries according to claim 1, characterized in that: It also includes a plurality of seals, which are respectively located between the end plate (20) and the flow channel frame (1), and between the flow channel frame (1) and the bipolar plate (4).

10. The bipolar plate liquid seepage detection device for vanadium batteries according to claim 3, characterized in that: The support block (100) has a rectangular cross-sectional shape.

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