Solid state polymer membrane electrolyzer and its water vapor transport flow field plate

Abstract

This invention discloses a solid polymer membrane electrolyzer and its water-gas transmission flow field plate, including a flow field plate body, an inlet and outlet area, a turbulence zone, a confluence zone, and a flow channel area. The inlet and outlet are equipped with distributors and guide slopes at their inlet and outlet ends. The turbulence zone and confluence zone are equipped with crescent-shaped boss structures. The flow channel area is divided into upstream and downstream parts. The upstream flow channel area adopts a periodically contracting flow channel and has circular boss structures in the non-contraction area. The downstream flow channel area has bubble-breaking barbed structures on both sides of the rib plate. This invention promotes the distribution and collection of electrolyte through optimized inlet and outlet structures. The upstream flow channel area increases the local flow velocity and achieves initial bubble dispersion through periodic contraction and the circular boss structure. Simultaneously, the bubble-breaking barbed structure in the downstream flow channel achieves secondary bubble breaking and rapid detachment, reducing internal blockage of the flow channel, significantly improving the uniformity of water-gas distribution, and enhancing electrolysis performance.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production, and more specifically, to a solid polymer membrane electrolyzer and its water-gas transmission flow field plate. Background Technology

[0002] Solid polymer membrane electrolysis for hydrogen production is a novel method of electrolysis using solid ion exchange membranes as diaphragms. It includes proton exchange membrane (PEM) electrolysis for hydrogen production and anion exchange membrane (AEM) electrolysis for hydrogen production. It has advantages such as high operating current density, high electrolysis efficiency, and good compatibility with renewable energy power generation.

[0003] As one of the core components of a solid polymer membrane electrolyzer, the flow field plate plays a crucial role not only in conducting electrons and providing mechanical support for the membrane electrode and porous transport layer structure, but also, more importantly, in uniformly transporting electrolyte to the electrode and promoting the timely discharge of reaction products. Therefore, optimizing the flow field plate structure is essential for improving the electrolytic performance of solid polymer membrane electrolyzers.

[0004] Existing bipolar plates and electrolyzers (such as the invention patent application CN202410446874.3) provide a variable-diameter flow channel, which improves the longitudinal mass transfer efficiency of the electrolyzer by changing the local flow cross-sectional area. However, they do not fully consider the blockage caused by bubbles continuously accumulating along the flow direction after the gas generated by the reaction enters the flow channel through the porous transport layer. This blockage significantly affects the inward mass transfer of the electrolyte, thereby reducing the operating efficiency and performance of the electrolyzer. Therefore, optimizing the flow characteristics of the flow channel, especially avoiding the blockage of the flow channel by the gas generated by the reaction, is of great significance for improving the efficiency and performance of solid polymer membrane electrolyzers. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, one objective of this invention is to provide a solid polymer membrane electrolyzer using a water-gas transmission flow field plate. This plate effectively improves the flow field velocity and two-phase uniformity, reduces fluid resistance, and promotes bubble breakage and escape, thereby enhancing mass transfer and reaction efficiency, and ultimately improving the overall performance and stability of water electrolysis for hydrogen production. Another objective of this invention is to provide a solid polymer membrane electrolyzer comprising the aforementioned water-gas transmission flow field plate.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a water-air transport flow field plate for a solid polymer membrane electrolyzer, comprising a flow field plate body, an inlet and outlet area, a turbulence area, a confluence area, and a flow channel area; the electrolyte flows in from the inlet, is evenly distributed into the flow channel of the flow channel area through the turbulence area, flows upward along the flow channel, enters the confluence area, and then flows out through the outlet; the flow channel area is divided into an upstream flow channel area and a downstream flow channel area; the upstream flow channel area includes multiple upstream flow channel ribs, which protrude along the fluid flow direction on the surface of the flow field plate body, wherein at least one pair of arc-shaped protrusions are provided on the inner side of adjacent two upstream flow channel ribs; the arc-shaped protrusions are symmetrically designed, and a flow channel contraction is formed between each pair of arc-shaped protrusions; a circular boss is provided at the center of each non-contraction area of ​​adjacent upstream flow channel ribs;

[0007] The downstream flow channel region includes multiple downstream flow channel ribs, which protrude from the surface of the flow field plate body along the extension direction of the upstream flow channel ribs; at least one pair of bubble-breaking barb structures are provided on both sides of the multiple downstream flow channel ribs, and are attached in an array to both sides of the downstream flow channel ribs; the bubble-breaking barb structure is a sharp protrusion structure, including a prism-shaped main body extending outward from the side edge of the downstream flow channel rib and toward the upstream flow channel region, and multiple sharp barb structures are provided at its top.

[0008] The turbulence zone is composed of multiple sets of crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the convex surface of the crescent-shaped protrusions pointing towards the inlet; the number of crescent-shaped protrusions in each set gradually increases along the fluid flow direction.

[0009] The confluence zone consists of multiple sets of second crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the concave surface of the second crescent-shaped protrusions pointing towards the outlet; the number of second crescent-shaped protrusions in each set gradually decreases along the fluid flow direction.

[0010] Using the above technical solution, the arc-shaped protrusions in the upstream flow channel can achieve periodic channel contraction, increasing local flow velocity; the circular protrusions in the non-contraction zone act as pins, aiming to achieve initial bubble dispersion. Building upon upstream optimization, the bubble-breaking barb structure attached to both sides of the downstream flow channel ribs can further divide bubbles into smaller bubble clusters. Its array structure can repeatedly cut the sub-bubbles segmented at the previous stage, preventing bubble re-aggregation and effectively avoiding gas blockage of the flow channel. Simultaneously, compared to point protrusions, the crescent-shaped protrusion structure in the turbulence and confluence zones ensures a more uniform distribution of electrolyte along the flow direction, enhancing the uniformity of flow velocity in the inlet zone and optimizing bubble management in the outlet zone.

[0011] Furthermore, the upstream and downstream flow channel ribs are integrated into a single structure. This design results in a smoother flow channel structure, further reducing fluid resistance.

[0012] Furthermore, multiple pairs of arc-shaped protrusions are evenly distributed, with the length of each pair of protrusions equal to the distance between two adjacent pairs. The minimum distance between the contraction points of adjacent flow channel contractions is no less than three-fifths of the distance between two adjacent flow channel ribs. The non-contracting portion of the flow channel has a rectangular structure. Further, the diameter of the projected plane of the circular boss is no less than one-third of the distance between the non-contracting portions of two adjacent upstream flow channel ribs, and no greater than three-fifths of the distance between the non-contracting portions of two adjacent upstream flow channel ribs. This configuration further optimizes the upstream flow channel structure, improves flow field velocity and two-phase uniformity, and initially promotes bubble dispersion.

[0013] Furthermore, the spike structure has a side-triangular pyramid shape, with its bottom connected to the side edge region of the prism-shaped main body to form a continuously transitioning multifaceted structure. The included angle between the contact planes of adjacent spikes ranges from 40° to 50°. Furthermore, the projections of the spike structures onto the bottom surface of the flow field plate are all isosceles triangles, with the longer side of the projected triangle of the top spike not exceeding half the shorter side of the projected triangle of the bubble-breaking spike structure; the acute angle in the isosceles triangle profile ranges from 15° to 20°. This configuration further optimizes the downstream flow channel structure and improves bubble breaking efficiency.

[0014] Furthermore, at least one rectangular protrusion is provided on the surface of the flow field plate at both ends of the inlet and outlet to form a distributor. Further, a directional slope is provided between adjacent distributors to form a guiding slope, the tangent of which is the ratio of the thickness of the flow field plate to the length of the rectangular protrusion along the fluid flow direction; the tangent is positive at the inlet and negative at the outlet, with a slope angle ranging from 20° to 30°. This configuration allows the distributors and guiding slope to guide the fluid smoothly and orderly in and out, reducing turbulence, eddies, and backflow at the inlet and outlet, lowering flow resistance, and improving fluid transport efficiency.

[0015] Furthermore, the flow field plate is square, with rounded corners of the same size at each of its four vertices. The radius of the rounded corners does not exceed 20% of the side length of the flow field plate, and is not less than 10% of the side length. This design ensures that the flow field plate maintains its structural strength while avoiding stress concentration at the corners.

[0016] Secondly, the present invention provides a solid polymer membrane electrolyzer, wherein the flow field plates on both sides of the cathode and anode are water vapor transport flow field plates as described above; the two ends of the flow field plate body are provided with fastening grooves of the same structure that cooperate with the electrolyzer.

[0017] Compared with the prior art, the present invention has the following technical effects:

[0018] (1) The crescent-shaped boss structure in the flow channel plate of the present invention is located in the turbulence zone and the confluence zone of the flow field plate, so that the electrolyte is more evenly distributed along the flow direction, enhances the uniformity of the flow velocity in the inlet zone, and optimizes the bubble management in the outlet zone.

[0019] (2) The variable diameter structure of the upstream channel in the flow channel plate of the present invention improves the fluid velocity and achieves the initial dispersion of bubbles by setting circular pins and reducing the local cross-sectional area of ​​the flow channel, thereby enhancing the reaction mass transfer.

[0020] (3) The bubble-breaking barbed structure in the downstream flow channel of the flow channel plate of the present invention introduces sharp geometric boundaries in the high gas content area, causing large bubbles that accumulate along the flow path to undergo asymmetric deformation and necking fracture during contact with the barbs, thereby dividing them into several small bubble groups. The periodic array arrangement of the barbed structure allows the sub-bubbles formed after the large bubbles break to undergo cascade breakage, avoiding the re-aggregation of bubble groups after breakage. Small bubbles are more easily discharged with the electrolyte, thereby reducing the risk of gas-liquid blockage caused by bubble aggregation in the flow channel, and thus optimizing the overall performance of the electrolyzer. Attached Figure Description

[0021] The invention, its features and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the planar structure of the flow field plate in an embodiment of the present invention;

[0023] Figure 2 This is an enlarged three-dimensional structural diagram of the upstream flow channel region in an embodiment of the present invention;

[0024] Figure 3 This is an enlarged three-dimensional structural diagram of the downstream flow channel region in an embodiment of the present invention;

[0025] Figure 4 yes Figure 1 A magnified view of a portion of the central turbulence zone;

[0026] Figure 5 yes Figure 1 A magnified view of a portion of the central confluence region;

[0027] Figure 6 yes Figure 1 A plan view of the crescent-shaped boss structure;

[0028] Figure 7 yes Figure 1 Enlarged 3D structural diagram of the inlet / outlet of the mid-flow field;

[0029] Figure 8 This is a schematic diagram of the planar structure of the traditional parallel flow field plate in Comparative Example 1;

[0030] Figure 9 This is a schematic diagram of the planar structure of the improved parallel flow field plate in Comparative Example 2;

[0031] Figure 10 These are polarization curves obtained by testing electrolytic cells using the flow field plates of the embodiment and the comparative embodiment under the same conditions.

[0032] Explanation of reference numerals in the attached diagram: 1-Upstream flow channel area; 2-Flow channel contraction; 3-Arch-shaped protrusion; 4-Circular boss; 5-Downstream flow channel area; 6-Bubble breaking barb structure; 7-Inlet; 8-Outlet; 9-Distributor; 10-Turbulence zone; 11-Crescent-shaped boss; 12-Confluence zone; 13-Guide slope; 14-Upstream flow channel rib; 15-Downstream flow channel rib; 16-Interlocking groove. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but these are not intended to limit the scope of the invention.

[0034] In the following detailed description, numerous specific details are set forth to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that well-known structures or methods (such as other components of an electrolyzer besides the flow field plate and the electrolyzer's operating method) are not shown in detail to avoid obscuring the gist of the invention; and the techniques not detailed in the following effect examples are readily available prior art.

[0035] Example

[0036] See Figures 1 to 3This embodiment provides a water-air transport flow field plate for a solid polymer membrane electrolyzer, including a flow field plate body. The base plate of the flow field plate is preferably rectangular, square, or circular, and more preferably square, with a preferred size of 516 mm × 516 mm, wherein the active area is 400 mm × 400 mm. The four vertices of the flow field plate body are provided with rounded corners of the same size, with a radius not exceeding 20% ​​and not less than 10% of the side length of the flow field plate, and more preferably 100 mm. This design ensures that the flow field plate maintains structural strength while avoiding stress concentration at the corners. The two ends of the flow field plate body are equipped with locking grooves 16 of the same structure that cooperate with the electrolyzer. The flow field plate structure also includes an inlet 7, a turbulence zone 10, an upstream flow channel zone 1, a downstream flow channel zone 5, a confluence zone 12, and an outlet 8. The electrolyte enters through the lower inlet 7. The inlet and outlet have the same structure as the locking tank 16, with a preferred length of 23 mm, a width of 284 mm, an upper corner radius of 9.5 mm, and a lower corner radius of 4.5 mm. The electrolyte is evenly distributed into each channel through the turbulence zone 10, which optimizes mass transfer uniformity. The electrolyte flows upward along the channel and enters the confluence zone 12, reducing fluctuations in parameters such as pressure and temperature within the electrolyzer caused by poor electrolyte flow at the outlet, and improving electrolyte collection efficiency. The channel area is divided into an upstream channel area and a downstream channel area, with the length parameters of the upstream and downstream channel areas being equal along the flow direction.

[0037] See Figure 2The electrolyte, after passing through the turbulence zone, enters the upstream flow channel zone 1. The upstream flow channel zone 1 includes multiple upstream flow channel ribs 14, which protrude along the fluid flow direction onto the surface of the flow field plate body. The upstream flow channel ribs 14 adopt a variable diameter structure, wherein at least one pair of arc-shaped protrusions 3 are provided on the inner side of adjacent upstream flow channel ribs 14; the arc-shaped protrusions 3 are symmetrically designed, and a flow channel contraction 2 is formed between each pair of arc-shaped protrusions 3; a circular boss 4 is provided at the center of each non-contraction area of ​​adjacent upstream flow channel ribs 14 to form a flow splitting pin. The ribs are preferably 336 mm long, 10 mm wide, and 0.75 mm high, with a spacing of 10 mm between adjacent ribs. Preferably, the non-contraction part of the upstream flow channel is a rectangular structure, with a circular boss 4 provided at the center of the bottom rectangle. The diameter of the projected plane of the circular boss 4 onto the bottom of the flow channel is not less than one-third of the distance between the non-contracting portions of two adjacent flow channel ribs, and not greater than three-fifths of the distance between the non-contracting portions of two adjacent flow channel ribs. More preferably, the projected diameter is 4 mm, and the height is the same as the height of the upstream flow channel rib 14. The length of the flow channel contraction portion 2 and the non-contracting portion is the same in the fluid flow direction. Each rib has four arc-shaped protrusions and four non-protrusions, and the longitudinal length of each arc-shaped protrusion and each non-protrusion is preferably 20 mm. With this configuration, when the fluid flows through the flow channel contraction portion 2, the reduced cross-sectional area of ​​the flow channel significantly increases the local flow velocity within the flow channel, thereby improving the reaction mass transfer efficiency.

[0038] In a solid polymer membrane electrolyzer, the gas generated during the reaction in the catalytic layer is discharged into the flow channel in the form of bubbles. The generated gas continuously flows into the flow channel through the porous transport layer, but the gas phase content in the two-phase flow near the inlet and upstream is not significant. The bubbles initially form small bubble clusters and tend to rise along the fluid flow direction. The circular protrusion 4 is located in the non-contracting part of the upstream flow channel region 1. It can indirectly change the local cross-sectional area of ​​the flow channel, increase the local flow velocity to carry away the bubbles in the upstream flow channel region 1, and also initially separate the bubble clusters transferred from the porous transport layer into smaller bubble clusters, suppressing the tendency of the fluid to accumulate into a plug flow and improving the bubble escape efficiency.

[0039] Fluid flows from the upstream flow channel region into the downstream flow channel region 5. See also Figure 3The downstream flow channel region includes multiple downstream flow channel ribs 15, which protrude from the surface of the flow field plate body along the extension direction of the upstream flow channel ribs 14. Bubble-breaking barb structures 6 are provided on both sides of the downstream flow channel ribs 15, preferably with four pointed tips. The angle between the contact planes of adjacent tips ranges from 40° to 50°, more preferably 45°. Their projection onto the bottom surface is an isosceles triangle, with the angle between the hypotenuse and the straight line of the rib approximately 15° to 20°, more preferably 18°, and the shorter side length preferably 3 mm. The leg length of the isosceles triangle projected onto the bottom surface by the pointed tips is preferably 1.5 mm. On a single rib, the distance between adjacent barb structures along the flow direction is consistent with the length of their shorter side; therefore, in this embodiment, a single flow channel has a total of 17 barb structures. The height of the barb structures is consistent with the height of the downstream flow channel ribs 15, both being 0.75 mm. Because bubbles accumulate along the fluid flow direction, the gas content of the two-phase flow in the downstream channel 5 is high, with many bubbles, some of which agglomerate into large bubbles that block the downstream channel 5, resulting in uneven distribution of the two phases and hindering the delivery of electrolyte. With this design, when the gas phase in the downstream fluid comes into contact with the bubble-breaking barbed structure 6, the sharp tips force the large bubbles to undergo asymmetric deformation, necking, and breakage, thus dispersing them into a group of small bubbles and inhibiting their re-agglomeration, accelerating the rapid discharge of gas.

[0040] The turbulence zone 10 consists of multiple sets of crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the convex surface of the crescent-shaped protrusions pointing towards the inlet; the number of crescent-shaped protrusions in each set gradually increases along the fluid flow direction.

[0041] The confluence zone 12 consists of multiple sets of second crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the concave surface of the second crescent-shaped protrusions pointing towards the outlet; the number of second crescent-shaped protrusions in each set gradually decreases along the direction of fluid flow.

[0042] See Figures 4 to 6 More specifically, the turbulence zone 10 and the confluence zone 12 of the flow field are respectively composed of three sets of crescent-shaped protrusions 11, a distributor 9, and a guiding slope 13. The number of the three sets of crescent-shaped protrusions 11 in the turbulence zone increases along the flow direction, while the number of the three sets of crescent-shaped protrusions 11 in the confluence zone decreases along the flow direction. The row with the fewest protrusions has at least one protrusion. In this embodiment, the preferred number of crescent-shaped protrusions is 30, and the number of protrusions in two adjacent groups is 3. The spacing between adjacent protrusions in each group is 10 mm, and the height is consistent with the height of the rib. The convex side of the crescent-shaped protrusion faces the inlet 7, and the concave side faces the outlet 8. Its planar structure is as follows: Figure 6As shown, the area within the solid line is formed by shifting the circular structure upwards a certain distance. R is preferably 2 mm, and h is 1.5 mm. This configuration, with its unique arc-shaped edge structure, enhances water inlet uniformity and reduces inlet resistance compared to other shapes of bosses. Simultaneously, its arc-shaped edge structure provides a transmission path for bubble rise and detachment, optimizing bubble management in the outlet 8 area.

[0043] like Figure 7 As shown, at least one distributor 9 is provided at both the inlet and outlet ends, preferably 91 in number, with a length of 2 mm, a width of 1 mm, and an adjacent spacing of 2 mm. A guide slope 13 is provided between adjacent distributors, with the angle determined to be 20.5° based on the tangent value of the slope angle. This arrangement allows the guide slope 9 to guide the fluid smoothly and orderly in and out, reducing turbulence, eddies, and backflow at the inlet and outlet, lowering flow resistance, and improving fluid transport efficiency.

[0044] The solid polymer membrane electrolyzer provided by this invention has water-gas transport flow field plates on both sides of the cathode and anode, as described above. The flow field plate body is fitted with the end plate component of the electrolyzer through the fastening groove 16. The fluid enters the turbulence zone through the inlet to achieve uniform distribution of the electrolyte, and is continuously accelerated in the upstream channel to suppress the initial growth of bubbles. In the downstream channel, the bubbles are further dispersed into small bubble groups through the barbed structure and discharged smoothly from the outlet, improving the uniformity of water-gas distribution and transport efficiency, thereby improving electrolysis performance.

[0045] Comparative Example 1

[0046] The solid polymer membrane electrolyzer used in this comparative example employs Figure 8 The conventional parallel flow field plate shown is used as a water-air transport flow field plate, and the other components are the same as those in the embodiment.

[0047] Comparative Example 2

[0048] The solid polymer membrane electrolyzer used in this comparative example employs Figure 9 The improved parallel flow field plate shown is a water-air transport flow field plate. The difference between it and Comparative Example 1 is that the flow field plate includes the same turbulence zone and confluence zone as the embodiment, while the rest of the components are the same as the embodiment.

[0049] See Figure 10 Anion exchange membrane electrolyzers with the same flow field structure as in the examples and comparative examples were used, and polarization curves were measured under constant current conditions on a test bench. Experiments under the same conditions showed that at low current densities, the electrochemical performance of the three flow fields did not differ significantly; however, as the current density continued to increase, the differences in the three polarization curves became significant (2.0 A cm⁻¹). -2In the example, the overpotential of the electrolyzer was reduced by 4.7% compared to Comparative Example 1. The overpotential of Comparative Example 2 was lower than that of Comparative Example 1, but higher than that of the example. This is because after the gas production of the electrolyzer increased under high current density, the flow field of the example significantly improved the water-gas transport, reduced concentration polarization, and thus improved the performance of the electrolyzer.

[0050] In summary, this invention provides a solid polymer membrane electrolyzer and its water-gas transmission flow field plate, including a flow field plate body, an inlet and outlet area, a turbulence zone, a confluence zone, and a flow channel area. The inlet and outlet are equipped with distributors and guide slopes at their inlet and outlet ends. The turbulence zone and confluence zone are equipped with crescent-shaped boss structures. The flow channel area is divided into upstream and downstream parts. The upstream flow channel area adopts a periodically contracting flow channel and has circular boss structures in the non-contraction area. The downstream flow channel area has bubble-breaking barbed structures on both sides of the rib plate. This invention promotes the distribution and collection of electrolyte through optimized inlet and outlet structures. The upstream flow channel area increases the local flow velocity and achieves initial bubble dispersion through periodic contraction and the circular boss structure. Simultaneously, the bubble-breaking barbed structure in the downstream flow channel achieves secondary bubble breaking and rapid detachment, reducing internal blockage of the flow channel, significantly improving the uniformity of water-gas distribution, and enhancing electrolysis performance.

[0051] Those skilled in the art should understand that variations can be implemented by combining existing technology with the above embodiments, which will not be elaborated here. Such variations do not affect the essence of the present invention, and will not be elaborated here either.

[0052] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above. Systems and structures not described in detail should be understood as being implemented in a conventional manner in the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. This does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention are still within the scope of protection of the present invention.

Claims

1. A water-air transport flow field plate for a solid polymer membrane electrolyzer, comprising a flow field plate body, an inlet and outlet area, a turbulence zone, a confluence zone, and a flow channel area; the electrolyte flows in from the inlet, is evenly distributed into the flow channel area through the turbulence zone, flows upward along the flow channel, enters the confluence zone, and then flows out through the outlet; characterized in that: The flow channel is divided into an upstream flow channel region and a downstream flow channel region. The upstream flow channel region includes multiple upstream flow channel ribs that protrude from the surface of the flow field plate body along the fluid flow direction. At least one pair of arc-shaped protrusions are provided on the inner side of two adjacent upstream flow channel ribs. The arc-shaped protrusions are symmetrically designed, and a flow channel contraction is formed between each pair of arc-shaped protrusions. A circular boss is provided at the center of each non-contraction area of ​​adjacent upstream flow channel ribs. The downstream flow channel region includes multiple downstream flow channel ribs, which protrude from the surface of the flow field plate body along the extension direction of the upstream flow channel ribs; at least one pair of bubble-breaking barb structures are provided on both sides of the multiple downstream flow channel ribs, and are attached in an array to both sides of the downstream flow channel ribs; the bubble-breaking barb structure is a sharp protrusion structure, including a prism-shaped main body extending outward from the side edge of the downstream flow channel rib and toward the upstream flow channel region, and multiple sharp barb structures are provided at its top. The turbulence zone is composed of multiple sets of crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the convex surface of the crescent-shaped protrusions pointing towards the inlet; the number of crescent-shaped protrusions in each set gradually increases along the fluid flow direction. The confluence zone consists of multiple sets of second crescent-shaped protrusions distributed from the center of the width of the flow field plate to both ends, with the concave surface of the second crescent-shaped protrusions pointing towards the outlet; the number of second crescent-shaped protrusions in each set gradually decreases along the fluid flow direction.

2. The water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 1, characterized in that, The upstream flow channel rib and the downstream flow channel rib are an integral structure.

3. The water-gas transport flow field plate of the solid polymer membrane electrolyzer according to claim 1 or 2, characterized in that, Multiple pairs of arc-shaped protrusions are evenly distributed, and the length of each pair of arc-shaped protrusions is equal to the distance between two adjacent pairs of arc-shaped protrusions; the minimum distance between the contraction points of adjacent flow channel contraction points is not less than three-fifths of the distance between two adjacent flow channel ribs; the non-contraction part of the flow channel has a rectangular structure.

4. The water-gas transport flow field plate of the solid polymer membrane electrolyzer according to claim 1 or 2, characterized in that, The diameter of the projected plane of the circular boss is not less than one-third of the distance between the non-contraction portions of two adjacent upstream flow channel ribs, and not greater than three-fifths of the distance between the non-contraction portions of two adjacent upstream flow channel ribs.

5. The water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 1 or 2, characterized in that, The spike structure has a side triangular pyramid shape, and its bottom is connected to the side edge region of the prism-shaped body to form a multifaceted structure with a continuous transition. The included angle between the contact planes of adjacent spikes is 40°~50°.

6. The water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 5, characterized in that, The projections of the spike structures onto the bottom surface of the flow field plate are all isosceles triangles, with the longer side of the projected triangle of the top spike not exceeding half the shorter side of the projected triangle of the bubble-breaking spike structure; the acute angles in the contour of the isosceles triangles range from 15° to 20°.

7. The water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 1 or 2, characterized in that, At least one rectangular protrusion is provided on the surface of the flow field plate body at both ends of the inlet and outlet to form a distributor.

8. The water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 7, characterized in that, A directional slope is set between adjacent distributors to form a guide slope. The tangent of the slope angle is the ratio of the thickness of the flow field plate body to the length of the rectangular boss along the fluid flow direction. The inlet end is positive and the outlet end is negative. The slope angle range is 20°~30°.

9. A water-gas transport flow field plate for a solid polymer membrane electrolyzer according to claim 1 or 2, characterized in that, The flow field plate is square, with rounded corners of the same size at all four vertices. The radius of the rounded corners does not exceed 20% of the side length of the flow field plate, and is not less than 10% of the side length.

10. A solid polymer membrane electrolyzer, characterized in that, The flow field plates on both sides of the cathode and anode are water vapor transport flow field plates as described in any one of claims 1 to 9; the two ends of the flow field plate body are equipped with snap-fit ​​grooves of the same structure that cooperate with the electrolytic cell.

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