Polar plate of proton exchange membrane electrolytic bath

Abstract

A pole plate of a proton exchange membrane electrolytic cell comprises an inlet, an outlet, a flow field area and a sealing structure. Wherein an inlet and an outlet are respectively formed in two ends of the polar plate and are communicated with the flow field region. The flow field area is provided with an inlet flow equalizing area, a flow channel area and an outlet flow equalizing area. Wherein a plurality of flow channel grooves are formed in the flow channel area in parallel, and each flow channel groove is in a curve shape and / or a broken line shape. Sealing structures are further arranged on the outer sides of the inlet, the outlet and the flow field area. The device is simple and compact in structure and convenient to process, on one hand, the fluid distribution uniformity in the polar plates of the electrolytic cell and between the polar plates is improved through the combination of multiple flow field areas, and on the other hand, the generation of annular flow is reduced through the non-linear flow channel grooves formed in the middle, the obstruction of air mass to water entering a diffusion layer and a catalytic layer is weakened, and the efficiency of the electrolytic cell is improved. And the water can be uniformly distributed on the whole diffusion layer and the catalyst layer, so that the cooling of the electrode is enhanced, the temperature distribution uniformity is improved, and the performance and the service life of the electrolytic cell can be obviously improved and prolonged.

Description

Technical Field

[0001] This invention belongs to the field of proton exchange membrane electrolysis hydrogen production technology, specifically relating to an electrode plate of a proton exchange membrane electrolyzer. Background Technology

[0002] A PEM (proton exchange membrane) electrolyzer is an electrolyzer that uses a proton exchange membrane for reactions. Based on the electrolysis of water, it generates electricity by breaking down water into hydrogen and oxygen. The main components of the electrolyzer include bipolar plates, a proton exchange membrane, and an electrolyte solution. In the electrolyzer, the electrolyte solution often uses a proton exchange membrane, which allows protons to pass through while blocking the flow of electrons.

[0003] PEM electrolyzers are characterized by fast response speed, high reaction efficiency, and low operating temperature. Due to their low operating temperature, PEM electrolyzers offer significant advantages in miniaturization and portability. In a PEM electrolyzer, the bipolar plates account for 60% of the total cost, making them one of the main components. Therefore, optimizing the design of the bipolar plate structure can significantly improve the performance and lifespan of the electrolyzer.

[0004] Bipolar plates typically incorporate flow field structures to guide fluid flow. These structures can be fabricated individually on the plates or assembled from a single flow channel plate. Regardless of the form, common flow field structures currently include parallel channels, serpentine channels, spiral flow fields, and interdigitated channels. A single straight or curved flow channel structure is commonly used, as seen in Chinese patent CN117660998A – a proton exchange membrane electrolyzer and its bipolar plate. While these flow field structures are simple to fabricate and low in cost, they still present the following problems:

[0005] (1) The flow channel structure directly affects the uniformity of flow. The fluid in each of the above flow channels has uneven distribution, which is not conducive to the efficient electrolysis process and the heat dissipation, and is prone to causing the local temperature of the electrolytic cell to be too high.

[0006] (2) Under high current density, annular flow is likely to occur in the flow field, forming gas clouds that hinder water from entering the gas diffusion layer and catalytic layer;

[0007] (3) In a single-direction flow, the fluid does not effectively cool the electrode, resulting in uneven temperature distribution and thermal stress, which can affect its performance and service life.

[0008] In summary, to address the problem of uneven distribution of water, gas, and heat in the bipolar plate flow field of existing proton exchange membrane electrolyzers, a novel proton exchange membrane electrolyzer bipolar plate structure is proposed to improve the above-mentioned issues. Summary of the Invention

[0009] The present invention provides an electrode plate for a proton exchange membrane electrolyzer to solve the above-mentioned problems.

[0010] The present invention adopts the following technical solution:

[0011] An electrode plate for a proton exchange membrane electrolyzer is provided, comprising an inlet, an outlet, a flow field zone, and a sealing structure;

[0012] The electrode plate has an inlet and an outlet at its two ends, respectively;

[0013] The flow field region is located on one side surface of the electrode plate, and its two ends are connected to the inlet and the outlet, respectively;

[0014] The flow field region is provided with an inlet flow equalization region, a flow channel region, and an outlet flow equalization region in sequence along the direction of fluid movement; the inlet flow equalization region and the outlet flow equalization region are one or more combinations of a lattice structure, a grid structure, and a parallel channel structure; the flow channel region is provided with multiple flow channel grooves in parallel, and the flow channel grooves are curved and / or broken line type;

[0015] The sealing structure is also provided on the outside of the inlet, outlet, and flow field area.

[0016] Optionally, the inlet and the outlet are waist-shaped blind holes;

[0017] Both the inlet and the outlet have lateral flow paths that connect to the flow field region.

[0018] Optionally, the inlet flow equalization zone and the outlet flow equalization zone are lattice-shaped structures with cylindrical protrusions arrayed inside.

[0019] Optionally, the cylindrical protrusions have the same geometric dimensions and the same spacing.

[0020] Optionally, the flow channel region is provided with multiple rows of ridge-like structures arranged in parallel;

[0021] The empty area between two adjacent ridge-like structures is the flow channel groove.

[0022] Optionally, the ridge structure has serrated sides, and the flow channel groove has a zigzag structure.

[0023] Optionally, the two sides of the ridge structure are square-toothed;

[0024] The top-view contours of the two sides of the ridge structure are translational structures, and the narrowest width of each flow channel groove is greater than or equal to the spacing of the cylindrical protrusions.

[0025] Optionally, the flow channel groove is deepened linearly or non-linearly along the direction of fluid movement;

[0026] The upper surfaces of the ridge-like structures are located on the same plane.

[0027] Optionally, the sealing structure includes a sealing groove and a sealing ring;

[0028] The sealing groove is located on the outer ring of the inlet, outlet, and flow field zone, and the sealing groove is connected end to end;

[0029] The sealing ring is installed in the sealing groove.

[0030] Optionally, the edge of the electrode plate is also provided with multiple mounting holes and / or positioning holes.

[0031] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0032] This invention features a simple and compact structure that is easy to manufacture. By combining multiple flow field regions, it improves the uniformity of fluid distribution within and between the electrodes of the electrolytic cell. Furthermore, the non-linear flow channel groove in the middle reduces the generation of annular flow, weakens the obstruction of gas masses to water entering the diffusion layer and catalyst layer, and helps maintain the uniform distribution of water throughout the diffusion layer and catalyst layer. This enhances the cooling of the electrodes, improves the uniformity of temperature distribution, and can significantly improve the performance and service life of the electrolytic cell. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a front view in a specific embodiment of the present invention;

[0035] Figure 2 for Figure 1 Sectional view along line AA;

[0036] Figure 3 This is a perspective view of a specific embodiment of the present invention;

[0037] Figure 4 This is a top view of the flow channel area in a specific embodiment of the present invention;

[0038] Figure 5 for Figure 4 Enlarged diagram of point B in the middle.

[0039] In the diagram: 1. Electrode plate, 2. Inlet, 3. Outlet, 4. Flow field zone, 5. Sealing groove, 6. Mounting hole, 41. Inlet flow equalization zone, 42. Flow channel zone, 43. Outlet flow equalization zone, 421. Ridge structure, 422. Flow channel groove. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0042] In the description of this invention, it should be understood that the relative relationships indicated by terms such as "upper" and "lower" are based on the order of contact with the material in the rotation direction in actual application, and are used for the convenience of describing this invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, and therefore should not be construed as a limitation of this invention.

[0043] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] It should be noted that, unless otherwise specified, the methods used in this invention are conventional methods; and the raw materials and apparatus used are, unless otherwise specified, conventional commercially available products.

[0045] It should also be noted that the "electrode plate" described in this invention includes not only any one of the bipolar plates in the traditional sense, but also electrode plates in combination, such as electrode plates that form a flow path by adding a flow channel plate.

[0046] like Figure 1 As shown, this embodiment provides an electrode plate for a proton exchange membrane electrolyzer, which mainly includes an inlet 2, an outlet 3, a flow field zone 4, and a sealing structure.

[0047] The electrode plate 1 is a flat plate structure with a waist-shaped blind hole machined at each end, serving as the inlet 2 and outlet 3 respectively, for connecting to the external fluid pipeline. Through holes are machined laterally at the inlet 2 and outlet 3 to connect to the flow field region 4.

[0048] Flow field region 4 is a platform structure on one side surface of the electrode plate, which is an open structure. In this embodiment, flow field region 4 is divided into three main regions ( Figure 1 The area (corresponding to the three dashed boxes in the middle) is sequentially provided with an inlet flow equalization zone 41, a flow channel zone 42, and an outlet flow equalization zone 43 along the fluid flow direction (inlet-outlet). Both the inlet flow equalization zone 41 and the outlet flow equalization zone 43 are recessed designs, and cylindrical protrusions are arrayed within them, forming a densely packed dotted structure for uniform distribution of the inlet fluid and rapid exit of the two-phase flow at the outlet. Optionally, the cylindrical protrusions have identical geometric dimensions and the same spacing.

[0049] The flow channel region 42 in the middle is provided with multiple flow channel grooves 422 arranged in parallel, and the flow channel grooves 422 are curved and / or broken line in shape. Optionally, the flow channel region 42 is also a sunken structure, in which multiple rows of ridge-like structures 421 are arranged in parallel. Figure 3 As shown, the empty area between two adjacent rows of ridge-like structures 421 is a flow channel 422, wherein each flow channel 422 connects the inlet flow equalization area 41 and the outlet flow equalization area 43 at both ends. Furthermore, the two sides of the ridge-like structure 421 are toothed when viewed from above, and the resulting flow channel has a zigzag structure. Specifically, combined with... Figure 4 As shown, a top view of the flow channel region 42 is taken, and the flow channel groove 422 is filled for easy viewing (the black area is the flow channel groove 422). In this embodiment, the two sides of the ridge structure 421 are square teeth, which can be equivalently viewed as a square wave shape. Moreover, the top view contours of the two sides of the ridge structure 421 are translational structures of each other, which can also be understood as two adjacent ridge structures 421 can be seamlessly spliced. Furthermore, as... Figure 5 As shown, to ensure that each flow channel 422 is a passageway, the narrowest point width d2 (the straight-line distance between the corners of the upper and lower staggered positive angles) of each flow channel 422 is designed to be greater than or equal to the spacing of the aforementioned cylindrical protrusions, thereby forming a right-angled polygonal structure for the flow channel 422. Optionally, in Figure 5 Based on this, and considering the flow regulation requirements, the ratio of the width d1 of the wider section of the flow channel 422 to the width d3 of the wider section of the ridge structure 421 is designed to be between 0.5 and 2. In this embodiment, the ratio is selected as 1.

[0050] Optionally, since the thickness of the common electrode plate 1 is generally uniform, in this embodiment, to increase fluidity and reduce fluid resistance, the flow channel groove 422 is designed to deepen linearly along the fluid movement direction; such as Figure 2 As shown, since the upper surfaces of the ridge structure 421 are located on the same plane, that is, the working surfaces of the electrode plate 1 are flush, it can also be understood that the height of the ridge structure 1 increases linearly, and the ridge height h1 near the inlet flow equalization zone 41 is less than the ridge height h2 near the outlet flow equalization zone 43.

[0051] A sealing structure is also provided on the outer side of inlet 2, outlet 3, and flow field zone 4. For example... Figure 1 and Figure 3 As shown, the sealing structure of this embodiment includes a sealing groove 5 and a sealing ring. The sealing groove 5 is located on the outer ring of the inlet 2, outlet 3, and flow field zone 4, and the sealing grooves 5 are connected end to end to form a connected groove structure. An integrally formed sealing ring is installed in the sealing groove 5. Furthermore, multiple mounting holes 6 are provided on the edge of the electrode plate 1 for mounting bolts, thereby ensuring the sealing performance between the plates in conjunction with the sealing structure.

[0052] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An electrode plate for a proton exchange membrane electrolyzer, characterized in that, This includes the import, export, flow field area, and sealing structure; The electrode plate has an inlet and an outlet at its two ends, respectively; The flow field region is located on one side surface of the electrode plate, and its two ends are connected to the inlet and the outlet, respectively; The flow field region is provided with an inlet flow equalization region, a flow channel region, and an outlet flow equalization region in sequence along the direction of fluid movement; the inlet flow equalization region and the outlet flow equalization region are one or more combinations of a lattice structure, a grid structure, and a parallel channel structure; the flow channel region is provided with multiple flow channel grooves in parallel, and the flow channel grooves are curved and / or broken line type; The sealing structure is also provided on the outside of the inlet, outlet, and flow field area.

2. The electrode plate of the proton exchange membrane electrolyzer according to claim 1, characterized in that, The inlet and the outlet are waist-shaped blind holes; Both the inlet and the outlet have lateral flow paths that connect to the flow field region.

3. The electrode plate of the proton exchange membrane electrolyzer according to claim 1 or 2, characterized in that, The inlet flow equalization zone and the outlet flow equalization zone are lattice-shaped structures with cylindrical protrusions arrayed inside.

4. The electrode plate of the proton exchange membrane electrolyzer according to claim 3, characterized in that, The cylindrical protrusions have the same geometric dimensions and the same spacing.

5. The electrode plate of the proton exchange membrane electrolyzer according to claim 4, characterized in that, The flow channel region is provided with multiple rows of ridge-like structures arranged in parallel; The empty area between two adjacent ridge-like structures is the flow channel groove.

6. The electrode plate of the proton exchange membrane electrolyzer according to claim 5, characterized in that, The ridge-like structure has teeth on both sides, while the flow channel has a zigzag structure.

7. The electrode plate of the proton exchange membrane electrolyzer according to claim 6, characterized in that, The ridge-like structure has square teeth on both sides; The top-view contours of the two sides of the ridge structure are translational structures, and the narrowest width of each flow channel groove is greater than or equal to the spacing of the cylindrical protrusions.

8. The electrode plate of the proton exchange membrane electrolyzer according to claim 5, characterized in that, The flow channel grooves deepen linearly or nonlinearly along the direction of fluid movement; The upper surfaces of the ridge-like structures are located on the same plane.

9. The electrode plate of the proton exchange membrane electrolyzer according to claim 1, characterized in that, The sealing structure includes a sealing groove and a sealing ring; The sealing groove is located on the outer ring of the inlet, outlet, and flow field zone, and the sealing groove is connected end to end; The sealing ring is installed in the sealing groove.

10. The electrode plate of the proton exchange membrane electrolyzer according to claim 1, characterized in that, The edge of the electrode plate is also provided with multiple mounting holes and / or positioning holes.

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