PEM electrolysis water anode plate flow field structure

Abstract

This invention discloses a flow field structure for a PEM electrolysis water anode plate, comprising a plate body with a sequentially connected inlet, an inlet transition zone, a reaction flow field, an outlet transition zone, and a water-gas outlet. The inlet and outlet transition zones each include a guide channel near the inlet and water-gas outlet, and a group of point-shaped flow-equalizing cylinders near the reaction flow field. The reaction flow field includes parallel channels on both sides and a serpentine channel in the middle, connected to each other. The water-gas outlet is connected to the anode flow field of the reaction flow field. Four hydrogen outlets are symmetrically arranged at the four corners of the plate body. This invention combines parallel and serpentine channels, maintaining a low pressure drop while extending the fluid flow time within the channels, which is beneficial for improving reaction efficiency. The guide channels and the group of point-shaped flow-equalizing cylinders ensure uniform fluid distribution, improving the efficiency of water electrolysis.

Description

Technical Field

[0001] This utility model relates to the field of electrolytic cell technology, and more specifically to a flow field structure for a PEM electrolytic water anode plate. Background Technology

[0002] The route of coupling renewable energy power generation systems with PEM (Proton Exchange Membrane) water electrolysis to produce hydrogen ("green electricity" + "green hydrogen") is widely regarded as one of the powerful weapons for achieving "carbon neutrality". The core components of a PEM electrolyzer include bipolar plates, a gas diffusion layer, a proton exchange membrane, and cathode / anode catalysts.

[0003] The reaction flow field on the electrode plate is where water electrolysis takes place. Reactants flow through channels in the flow field into the gas diffusion layer and membrane electrode area to undergo catalytic reaction. The produced gas and heat generated by the reaction also flow out through the channels. Common channels include dot channels, parallel channels, serpentine channels, and spiral channels. Parallel channels have low flow resistance and low pressure loss, but the fluid distribution in each channel is uneven. Serpentine channels can effectively overcome this drawback. Serpentine channels are further divided into single serpentine, double serpentine, and multi-serpentine channels. Multi-channel serpentine channels, with the same catalytic activity area, help reduce channel bends and lower pressure drop, and even if a single channel is blocked, it will not affect the use of the electrolyzer. Spiral channels have strong drainage capabilities, and the staggered arrangement of channels near the inlet and outlet makes the fluid distribution more uniform, but they also have problems such as larger pressure drop, susceptibility to short-circuiting of fluid flow, and more complex processing.

[0004] Chinese patent CN 116770336 A introduces a bipolar plate and proton exchange membrane electrolyzer, focusing on the arrangement of parallel flow channels with gradually varying widths. The electrolyzer structure is simple and compact, with low stress concentration and easy processing. Chinese patent CN 116988080 A introduces an electrolyzer structure, focusing on reducing the pressure on the sealing structure and improving sealing performance. Chinese patent CN219861604 U introduces a PEM electrolyzer and stack electrode design, focusing on improving thermal management efficiency.

[0005] Therefore, the existing PEM electrolyzer flow field settings still have problems such as uneven fluid distribution, low gas discharge efficiency, and low catalytic efficiency. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a flow field structure for a PEM electrolysis anode plate that extends the residence time of fluid in the electrode plate while maintaining a low pressure drop. The design of the inlet and outlet transition zone guide channels and the point-shaped flow equalization cylinder group can effectively regulate the fluid flow rate, achieve uniform water distribution, and improve the efficiency of water electrolysis.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows.

[0008] A PEM electrolysis water anode plate flow field structure includes a plate body with a water inlet, an inlet transition zone, a reaction flow field, an outlet transition zone, and a water-gas outlet arranged sequentially on the plate body. The inlet and outlet transition zones each include a guide channel near the water inlet and water-gas outlet, and a group of point-shaped flow-equalizing cylinders near the reaction flow field. The reaction flow field includes parallel channels on both sides and a serpentine channel in the middle of the reaction flow field, with the parallel channels and the serpentine channel connected. The water-gas outlet is connected to the anode flow field of the reaction flow field. Four cathode flow fields connected to the reaction flow field and a hydrogen outlet for hydrogen flow are symmetrically arranged at the four corners of the plate body.

[0009] To further optimize the technical solution, the direction of the flow guide channel is arranged diverging from the water inlet or water-air inlet end, and the width of the flow guide channel is a structure that is thick in the middle and thin at both ends.

[0010] The technical solution is further optimized so that the width of the middle of the flow channel is 5mm and the width of the two sides of the flow channel is 2mm.

[0011] The technical solution is further optimized. The point-like flow equalization cylinder group includes several cylindrical blocks, and the distance between the centers of the bottom surfaces of adjacent cylinders in the lateral direction is 8mm.

[0012] To further optimize the technical solution, the diameter of the cylindrical block is 1mm-5mm and the height is 0.5mm-1mm.

[0013] To further optimize the technical solution, the parallel flow channel is composed of several parallel flow channel ridges. The width of the parallel flow channel is 1mm-5mm, the width of the parallel flow channel ridge is 1mm-4mm, and the length of the parallel flow channel ridge is 120mm-150mm.

[0014] To further optimize the technical solution, the serpentine flow channel is composed of several serpentine flow channel ridges. The width of the serpentine flow channel is 1mm-5mm, the ridge width between the same serpentine flow channel is 1mm-4mm, and the ridge width between different serpentine flow channels is 1.5mm-3mm.

[0015] The technological advancements achieved by this utility model are as follows, due to the adoption of the above technical solutions.

[0016] This utility model provides a flow field structure for a PEM electrolysis anode plate, which combines parallel flow channels and serpentine flow channels. This maintains a low pressure drop while extending the flow time of the fluid in the flow channels, which is beneficial to improving the reaction efficiency. The arrangement of the flow guiding channels and the point-shaped flow equalizing cylinder group makes the fluid flow and distribution uniformly, thereby improving the efficiency of water electrolysis. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Among them: 1. Inlet, 2. Inlet transition zone, 3. Reaction flow field, 4. Outlet transition zone, 5. Water and gas outlet, 6. Guide channel, 7. Point-shaped flow equalization cylinder group, 8. Parallel channel, 9. Serpentine channel, 10. Hydrogen outlet, 11. Plate. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] A PEM electrolysis water anode plate flow field structure, combined with Figure 1 As shown, the device includes a plate 11, on which are arranged sequentially an inlet 1, an inlet transition zone 2, a reaction flow field 3, an outlet transition zone 4, and a water-gas outlet 5. The water-gas outlet 5 is connected to the anode flow field of the reaction flow field and is used to discharge water and unreacted electrolyzed water. Four hydrogen outlets 10 are symmetrically arranged at the four corners of the plate 11, and the four hydrogen outlets are connected to the cathode flow field of the reaction flow field for hydrogen to flow out.

[0021] Both the inlet transition zone 2 and the outlet transition zone 4 include a flow guide channel 6 and a group of point-shaped flow equalizing cylinders 7. The flow guide channel 6 is located on the side near the inlet 1 and the water-gas outlet 5. The group of point-shaped flow equalizing cylinders 7 is located on the side of the reaction flow field 3. The direction of the flow guide channel 6 is diverging from the inlet or the water-gas outlet end. The width of the flow guide channel 6 is a structure that is thick in the middle and thin at both ends. The width of the middle of the flow guide channel 6 is 5mm, and the width of the two sides of the flow guide channel 6 is 2mm. The number of flow guide channels 6 is set to 5.

[0022] The point-like flow equalization cylinder group 7 includes several cylindrical blocks, with a quantity of 39. The diameter of the cylindrical blocks is 1mm-5mm, the height is 0.5mm-1mm, and the distance between the centers of the bottom surfaces of adjacent cylinders is 8mm.

[0023] The reaction flow field 3 includes a parallel flow channel 8 and a serpentine flow channel 9. The parallel flow channel 8 is located on both sides of the reaction flow field, and the serpentine flow channel 9 is located in the middle of the reaction flow field. The parallel flow channel 8 and the serpentine flow channel 9 are connected.

[0024] The parallel flow channel 8 is composed of several parallel flow channel ridges. The width of the parallel flow channel is 1mm-5mm, the width of the parallel flow channel ridge is 1mm-4mm, and the length of the parallel flow channel ridge is 120mm-150mm.

[0025] The serpentine flow channel 9 is composed of several serpentine flow channel ridges. The width of the serpentine flow channel is 1mm-5mm, the ridge width between the same serpentine flow channel is 1mm-4mm, and the ridge width between different serpentine flow channels is 1.5mm-3mm.

[0026] In this invention, during hydrogen production, liquid water enters through the inlet. After being uniformly distributed by the guiding channels and point-like uniform-flow cylindrical fluid groups within the inlet transition zone, the liquid water flows evenly into the reaction zone, where parallel and serpentine flow channels coexist. This combination of parallel and serpentine flow channels maintains a low pressure drop while extending the fluid's flow time within the channels, thus improving reaction efficiency. Within the reaction flow field, the liquid water undergoes an oxygen evolution reaction, producing O2 and H2. + O2 and unreacted water are discharged through the water vapor outlet, H + Through the proton exchange membrane, electrons are gained on the cathode side, a reduction reaction occurs, hydrogen gas is produced, and the hydrogen gas is discharged from the electrolyzer through the hydrogen outlet.

Claims

1. A flow field structure for a PEM electrolytic water anode plate, characterized in that: The plate (11) includes an inlet (1), an inlet transition zone (2), a reaction flow field (3), an outlet transition zone (4), and a water-gas outlet (5) connected in sequence. The inlet transition zone (2) and the outlet transition zone (4) each include a guide channel (6) near the inlet and the water-gas outlet and a group of point-shaped flow-equalizing cylinders (7) near the reaction flow field. The reaction flow field (3) includes a parallel channel (8) on both sides of the reaction flow field and a serpentine channel (9) in the middle of the reaction flow field. The parallel channel (8) and the serpentine channel (9) are connected. The water-gas outlet is connected to the anode flow field of the reaction flow field. Four cathode flow fields connected to the reaction flow field and hydrogen outlets (10) for hydrogen flow are symmetrically arranged at the four corners of the plate (11).

2. The flow field structure of a PEM electrolytic water anode plate according to claim 1, characterized in that: The direction of the guide channel (6) is arranged diverging from the water inlet or water-air inlet end, and the width of the guide channel is a structure that is thick in the middle and thin at both ends.

3. The flow field structure of a PEM electrolytic water anode plate according to claim 2, characterized in that: The width of the middle part of the guide channel (6) is 5mm, and the width of the two sides of the guide channel (6) is 2mm.

4. The flow field structure of a PEM electrolytic water anode plate according to claim 1, characterized in that: The point-like flow equalization cylinder group (7) includes several cylindrical blocks, and the distance between the centers of the bottom surfaces of adjacent cylinders in the lateral direction is 8 mm.

5. The flow field structure of a PEM electrolytic water anode plate according to claim 4, characterized in that: The diameter of the cylindrical block is 1mm-5mm, and the height is 0.5mm-1mm.

6. The flow field structure of a PEM electrolytic water anode plate according to claim 1, characterized in that: The parallel flow channel (8) is composed of several parallel flow channel ridges. The width of the parallel flow channel is 1mm-5mm, the width of the parallel flow channel ridge is 1mm-4mm, and the length of the parallel flow channel ridge is 120mm-150mm.

7. The flow field structure of a PEM electrolytic water anode plate according to claim 1, characterized in that: The serpentine flow channel (9) is composed of several serpentine flow channel ridges. The width of the serpentine flow channel is 1mm-5mm, the ridge width between the same serpentine flow channel is 1mm-4mm, and the ridge width between different serpentine flow channels is 1.5mm-3mm.

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