Polar plate and electrolytic bath

Abstract

The polar plate comprises a plate body with a flow field area, the flow field area is provided with a plurality of convex ribs which extend in the length direction of the polar plate and are distributed at intervals in the width direction of the polar plate, and a flow channel is formed between every two adjacent convex ribs. The runner comprises a first region and a second region which are communicated along the thickness direction of the polar plate, the first region is positioned on one side, close to the membrane electrode assembly, of the second region, and the sectional area of the first region is smaller than that of the second region. When the flow rate of the electrolyte is certain, the pressure intensity in the first area is greater than the pressure intensity in the second area, so that a flow pressure difference can be formed between the first area and the second area in the same flow channel, and gas positioned at the membrane electrode can flow towards the plate body along the membrane electrode assembly under the action of the flow pressure difference; and gas generated after electrolysis is prevented from being accumulated at the membrane electrode, so that the possibility of a gas aggregation effect at the membrane electrode is reduced, and the hydrogen production efficiency of the electrolytic cell is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electrolytic cells, and in particular to a polar plate and an electrolytic cell. Background Art

[0002] The proton exchange membrane (PEM) electrolyzer is mainly composed of membrane electrodes, diffusion layers, bipolar plates, seals, and end plates. The PEM electrolyzer requires an external power supply when working to cause the water in the electrolyzer to undergo an oxidation-reduction reaction, and to precipitate oxygen on the anode side of the bipolar plate and hydrogen on the cathode side of the bipolar plate. However, during the operation of the PEM electrolyzer, the generated gas will adhere to the proton exchange membrane. As the power of the PEM electrolyzer increases, more and more gas will adhere to the proton exchange membrane, thereby forming a gas film aggregation effect, which in turn affects the hydrogen production efficiency of the PEM electrolyzer. Summary of the invention

[0003] In view of this, the present application provides a polar plate and an electrolyzer to solve the technical problem in the prior art that the gas film aggregation effect affects the hydrogen production efficiency of the PEM electrolyzer.

[0004] The present application provides an electrode plate, which includes a plate body, the plate body having a flow field area, the flow field area is provided with a plurality of ribs, the plurality of ribs extend along the length direction of the electrode plate, and are spaced apart along the width direction of the electrode plate, and a flow channel is formed between two adjacent ribs; wherein, along the thickness direction of the electrode plate, the flow channel includes a first area and a second area that are connected, the first area is located on a side of the second area close to the membrane electrode assembly, and the cross-sectional area of ​​the first area is smaller than the cross-sectional area of ​​the second area.

[0005] In an embodiment of the present application, water flowing into the electrolyzer flows into the various flow channels in the flow field area through the water inlet cavity, so that the water flows in the various flow channels and simultaneously undergoes oxidation-reduction reactions, thereby generating hydrogen and oxygen at the membrane electrode. After the water flows out of the various flow channels in the flow field area, it flows out of the electrolyzer through the water outlet cavity, thereby realizing the electrolysis of water to produce hydrogen in the electrolyzer.

[0006] Among them, along the thickness direction of the electrode plate, the space for circulating water in each flow channel can be divided into a first area and a second area. The first area and the second area are distributed and connected along the thickness direction of the electrode plate, and the first area is located on the side of the second area close to the membrane electrode assembly.

[0007] Specifically, along the thickness direction of the electrode plate, the cross-sectional area of ​​the first region is smaller than the cross-sectional area of ​​the second region. When the flow rate of water flowing into each flow channel is constant, the pressure in the first region is greater than the pressure in the second region, so that a flow pressure difference can be formed between the first region and the second region in the same flow channel. Through such a design, the gas at the membrane electrode can flow along the membrane electrode assembly toward the plate body under the action of the flow pressure difference, so as to avoid the accumulation of gas generated after electrolysis at the membrane electrode, thereby reducing the possibility of gas aggregation effect at the membrane electrode, which is beneficial to improving the hydrogen production efficiency of the electrolyzer.

[0008] In a possible implementation, the cross-sectional area of ​​the first region is S1, the cross-sectional area of ​​the second region is S2, and S1 and S2 satisfy 0.1≤S1 / S2≤0.9.

[0009] In a possible embodiment, the plate body includes a main plate and a plurality of sub-plates, and along the thickness direction of the electrode plate, each of the convex ribs protrudes relative to the main plate, and each of the sub-plates is respectively connected to a side of each of the convex ribs away from the main plate, and each of the convex ribs is located within the projection range of each of the sub-plates.

[0010] Along the width direction of the electrode plate, there is a gap between two adjacent sub-plates, the gap forms the first area of ​​the flow channel, and the second area of ​​the flow channel is formed between two adjacent convex ribs.

[0011] In a possible implementation, guide surfaces are provided at both ends of the sub-plate along the width direction of the electrode plate, and along the thickness direction of the electrode plate, the guide surfaces are located on the side of the sub-plate facing the main plate; wherein the guide surfaces are plane or arc surfaces.

[0012] In a possible implementation, along the width direction of the electrode plate, the distance between two adjacent sub-plates is L1, the distance between two adjacent ribs is L2, and L1 and L2 satisfy 0.1≤L1 / L2≤0.9, and L1 satisfies 0.1mm≤L1.

[0013] In a possible implementation, along the thickness direction of the electrode plate, the thickness of the sub-plate is H1, the thickness of the convex rib is H2, H1 and H2 satisfy 0.1≤H1 / H2≤1, and H1 satisfies 0.1mm≤H1≤5mm.

[0014] In a possible embodiment, each of the convex ribs includes a first extension portion, a second extension portion and a main body portion, and along the width direction of the electrode plate, the first extension portion and the second extension portion are connected to both sides of the main body portion, and along the thickness direction of the electrode plate, the upper surfaces of the first extension portion and the second extension portion are flush with the upper surface of the main body portion.

[0015] Along the width direction of the electrode plate, the first extension portion of the convex rib and the second extension portion of the adjacent convex rib form the first region of the flow channel, and the second region of the flow channel is formed between two adjacent convex ribs.

[0016] In a possible implementation manner, the first extension portion, the second extension portion, and the main body portion are an integrally formed structure.

[0017] The present application also provides an electrolytic cell, which includes an electrode plate and a membrane electrode assembly. The membrane electrode assembly and the electrode plate are stacked along the thickness direction of the electrolytic cell; wherein the electrode plate adopts any of the electrode plates described above.

[0018] In an embodiment of the present application, the membrane electrode assembly includes an electrode plate, a diffusion layer and a membrane electrode. Along the thickness direction of the electrolytic cell, the diffusion layer is located between the electrode plate and the membrane electrode. The diffusion layer has a transmission channel connecting the membrane electrode and the flow channel. The transmission channel is used to transmit electrolyte and gas to ensure the stability and reliability of the electrolytic cell during operation.

[0019] During the operation of the electrolyzer, when water flows in the flow channel, at least part of the water can diffuse along the plate body toward the membrane electrode assembly, so that a redox reaction occurs at the membrane electrode and gas is generated. Since the flow channel is divided into a first region and a second region that are interconnected, the first region is located on a side of the second region close to the membrane electrode, and the cross-sectional area of ​​the first region is smaller than the cross-sectional area of ​​the second region, so that a flow pressure difference can be formed between the first region and the second region in the flow channel, so that the gas at the membrane electrode can flow along the membrane electrode assembly toward the plate body under the action of the flow pressure difference, so as to avoid the accumulation of gas generated after electrolysis at the membrane electrode, thereby reducing the possibility of gas aggregation effect at the membrane electrode, which is beneficial to improving the hydrogen production efficiency of the electrolyzer.

[0020] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 This is a schematic structural diagram of a plate provided in the present application in a specific embodiment; Figure 2 for Figure 1 A cross-sectional view of Figure 3 A cross-sectional view of the rib provided in the present application in a first embodiment; Figure 4 This is a schematic structural diagram of a guide surface provided in the present application in a specific embodiment; Figure 5 This is a cross-sectional view of the rib provided in the present application in the second embodiment.

[0023] Description of reference numerals: 1-Plate body; 11- Mainboard; 111-convex rib; 111a-first extension portion; 111b-second extension; 111c-main body; 112-flow channel; 112a-first area; 112b - second area; 12-Vice board; 121- guide surface; 2-Membrane electrode assembly.

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0025] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0026] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0027] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0028] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0029] The embodiment of the present application provides a plate for an electrolytic cell, such as Figure 1 , Figure 2 and Figure 3 As shown, the electrode plate includes a plate body 1, which has a flow field area. The flow field area is provided with a plurality of ribs 111, which extend along the length direction of the electrode plate and are spaced apart along the width direction of the electrode plate, and a flow channel 112 is formed between two adjacent ribs 111.

[0030] Among them, along the thickness direction of the electrode plate, the flow channel 112 includes a first area 112a and a second area 112b that are connected. The first area 112a is located on the side of the second area 112b close to the membrane electrode assembly 2, and the cross-sectional area of ​​the first area 112a is smaller than the cross-sectional area of ​​the second area 112b.

[0031] In the embodiment of the present application, the membrane electrode assembly 2 includes a membrane electrode, and the electrolyte undergoes a redox reaction at the membrane electrode to produce hydrogen and oxygen. The plate body 1 also has a cavity area, which includes a water inlet cavity (not marked in the figure) and a water outlet cavity (not marked in the figure). Along the length direction of the electrode plate, the water inlet cavity and the water outlet cavity are distributed on both sides of the flow field area, and the water inlet cavity and the water outlet cavity are interconnected with each flow channel 112 in the flow field area. The water inlet cavity, the water outlet cavity and the flow channel 112 are all used to circulate the electrolyte.

[0032] In a possible implementation, the electrolyte may be water.

[0033] During the operation of the electrolyzer, water flowing into the electrolyzer flows into the flow channels 112 in the flow field area through the water inlet cavity, so that the water undergoes an oxidation-reduction reaction while flowing in the flow channels 112, thereby generating hydrogen and oxygen at the membrane electrode. After the water flows out of the flow channels 112 in the flow field area, it flows out of the electrolyzer through the water outlet cavity, thereby realizing the electrolysis of water to produce hydrogen in the electrolyzer.

[0034] Among them, along the thickness direction of the electrode plate, the space for circulating water in each flow channel 112 can be divided into a first area 112a and a second area 112b. The first area 112a and the second area 112b are distributed and connected along the thickness direction of the electrode plate, and the first area 112a is located on the side of the second area 112b close to the membrane electrode assembly 2.

[0035] Specifically, along the thickness direction of the electrode plate, the cross-sectional area of ​​the first region 112a is smaller than the cross-sectional area of ​​the second region 112b. When the flow rate of water flowing into each flow channel 112 is constant, the pressure in the first region 112a is greater than the pressure in the second region 112b, so that a flow pressure difference can be formed between the first region 112a and the second region 112b in the same flow channel 112. Through such a design, the gas at the membrane electrode can flow along the membrane electrode assembly 2 toward the plate body 1 under the action of the flow pressure difference, so as to avoid the accumulation of gas generated after electrolysis at the membrane electrode, reduce the possibility of gas aggregation effect at the membrane electrode, and thus promote gas transmission, reduce mass transfer loss of the electrolyzer, and improve the hydrogen production efficiency of the electrolyzer.

[0036] In one possible implementation, the cross-sectional area of ​​each flow channel 112 can remain unchanged along the length direction of the electrode plate, so that the changes in the flow rate, pressure and resistance encountered by the fluid during the flow are relatively small, which can reduce the possibility of turbulence and other phenomena, and is beneficial to reducing the energy loss of the fluid when flowing in the flow channel 112, and improving the stability of the fluid flow.

[0037] At the same time, when the flow of the fluid is relatively stable, the erosion and wear of the flow channel 112 can be reduced, which is beneficial to increasing the service life of the electrode plate.

[0038] In addition, when the cross-sectional area of ​​each flow channel 112 remains unchanged, it is more conducive to the staff to control the flow rate of the fluid to improve the accuracy of the fluid flow rate control, so that more gas can be generated during the flow of water in the flow channel 112, thereby further improving the hydrogen production efficiency of the electrolyzer.

[0039] In one possible embodiment, along the length direction of the electrode plate, the inlet cross-sectional area of ​​each flow channel 112 is smaller than the outlet cross-sectional area, so that after the water flows into the flow channel 112, the flow velocity of the water can be reduced, so as to increase the flow time of the water in the flow channel 112, so that it can fully carry out the redox reaction, thereby increasing the amount of gas generated, and a large amount of gas can also be discharged through the outlet with an enlarged cross-sectional area, so as to increase the gas generation while improving the exhaust efficiency of the electrode plate, thereby improving the working efficiency of the electrolytic cell.

[0040] In a specific embodiment, Figure 1 , Figure 2 and Figure 3 As shown, the cross-sectional area of ​​the first region 112a is S1, the cross-sectional area of ​​the second region 112b is S2, and S1 and S2 satisfy 0.1≤S1 / S2≤0.9.

[0041] In the embodiment of the present application, the ratio of the cross-sectional area of ​​the first region 112a to the cross-sectional area of ​​the second region 112b can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, etc.

[0042] When the ratio of the cross-sectional area of ​​the first region 112a to the cross-sectional area of ​​the second region 112b satisfies 0.1≤S1 / S2≤0.9, the ratio of the cross-sectional areas of the two regions is within a suitable range. By means of such a design, it is possible to improve the transmission and diffusion efficiency of the electrolyte and gas along the thickness direction of the plate while ensuring that the two flow smoothly in the flow channel 112, avoiding the risk of the flow channel 112 being too narrow due to a small ratio, thereby reducing the possibility of blockage of the electrolyte and gas during the transmission and diffusion process, and avoiding the risk of the first region 112a and the second region 112b being unable to form a significant flow pressure difference due to a large ratio, so as to ensure that the gas at the membrane electrode can flow along the membrane electrode assembly 2 toward the plate body 1 under the action of the flow pressure difference, thereby avoiding the accumulation of the gas generated after electrolysis at the membrane electrode, reducing the possibility of gas aggregation effect at the membrane electrode, and facilitating the improvement of the hydrogen production efficiency of the electrolyzer.

[0043] In a specific embodiment, Figure 1 , Figure 2 and Figure 3 As shown, the plate body 1 includes a main plate 11 and a plurality of sub-plates 12. Along the thickness direction of the plate, each rib 111 protrudes relative to the main plate 11. Each sub-plate 12 is respectively connected to a side of each rib 111 away from the main plate 11, and each rib 111 is located within the projection range of each sub-plate 12.

[0044] There is a gap between two adjacent sub-plates 12 along the width direction of the electrode plate, and the gap forms a first area 112 a of the flow channel 112 . The second area 112 b of the flow channel 112 is formed between two adjacent ribs 111 .

[0045] In the embodiment of the present application, along the thickness direction of the electrode plate, multiple sub-plates 12 are correspondingly connected to multiple ribs 111, and there is a gap between each sub-plate 12, which can connect the membrane electrode assembly 2 and the flow channel 112, so that the electrolyte can diffuse in the direction toward the membrane electrode assembly 2, thereby causing an oxidation-reduction reaction at the membrane electrode to generate gas, and at the same time, the generated gas flows in the direction toward the flow channel 112, so as to avoid the risk of gas accumulation at the membrane electrode and causing a gas aggregation effect at the membrane electrode.

[0046] Specifically, each convex rib 111 is located within the projection range of each sub-plate 12, that is, along the width direction of the electrode plate, the width dimension of each convex rib 111 is smaller than the width dimension of each sub-plate 12, so that a first area 112a of the flow channel 112 can be formed between two adjacent sub-plates 12, and a second area 112b of the flow channel 112 can be formed between two adjacent convex ribs 111.

[0047] Among them, the cross-sectional area of ​​the first region 112a is smaller than the cross-sectional area of ​​the second region 112b, so that a flow pressure difference can be formed between the first region 112a and the second region 112b located in the same flow channel 112, so as to promote the gas to flow along the membrane electrode assembly 2 toward the flow channel 112 under the action of the flow pressure difference, which is beneficial to improve the hydrogen production efficiency of the electrolyzer while ensuring the working stability of the electrolyzer.

[0048] In addition, the rib 111 and the main board 11 can be an integrally formed structure to improve the connection reliability between the rib 111 and the main body 11 and improve the overall structural strength of the board 1. At the same time, the integrally formed method is conducive to reducing the production process of the board 1 and improving the production efficiency of the board 1.

[0049] In a specific embodiment, Figure 3 As shown, along the thickness direction of the electrode plate, each rib 111 is symmetrically arranged with respect to each auxiliary plate 12 .

[0050] In the embodiment of the present application, when each rib 111 and each sub-plate 12 are axially symmetrically arranged along the thickness direction of the electrode plate, each sub-plate 12 extends to both sides along the width direction of the electrode plate at an equal distance relative to each rib 111, so as to ensure that the width dimensions of the first area 112a of each flow channel 112 are equal.

[0051] Specifically, during the operation of the electrolytic cell, the first regions 112a having the same width dimension can make the electrolyte in the flow channel 112 diffuse evenly along the plate body 1 toward the membrane electrode assembly 2, thereby avoiding the risk of different amounts of electrolyte undergoing redox reactions in each flow channel 112 due to different width dimensions of each first region 112a, thereby ensuring the uniformity of the reaction in the flow field area, which is beneficial to improving the stability and reliability of the electrolytic cell during operation.

[0052] At the same time, during the operation of the electrolytic cell, the first regions 112a with the same width can also make the gas located at the membrane electrode diffuse evenly toward the direction of the flow channel 112, avoiding the risk of uneven gas dispersion due to the different width dimensions of the first regions 112a, which is beneficial to improving the overall exhaust efficiency of the electrolytic cell, thereby further improving the working efficiency of the electrolytic cell.

[0053] In addition, along the thickness direction of the electrode plate, when each rib 111 is axially symmetrically arranged with each sub-plate 12, the first area 112a and the second area 112b can also be axially symmetrically arranged to ensure the stability of the fluid flow in this direction, which is beneficial to balance the turbulence degree and flow rate of the fluid, reduce the pressure loss generated by the fluid during the flow process, and thus improve the working performance of the electrolytic cell.

[0054] In a specific implementation, the rib 111 and the sub-plate 12 are fixedly connected by welding or bonding.

[0055] In the embodiment of the present application, along the thickness direction of the electrode plate, the upper surface of the rib 111 and the sub-plate 12 can be fixedly connected by welding or bonding to improve the stability and reliability of the connection between the two, so as to avoid the risk of collapse of the sub-plate 12 or misalignment between the sub-plate 12 and the rib 111 during the subsequent lamination process, so as to improve the safety and reliability of the electrolytic cell during the assembly process, and to ensure the stability of the electrolytic cell during operation. At the same time, the welding or bonding method is easy to operate, which is conducive to reducing the manufacturing difficulty and production cost of the plate body 1, and is more in line with actual production needs.

[0056] In a specific embodiment, Figure 4 As shown, along the width direction of the electrode plate, guide surfaces 121 are provided at both ends of the sub-plate 12, and along the thickness direction of the electrode plate, the guide surface 121 is located on the side of the sub-plate 12 facing the main plate 11, so that in the process of gas diffusion from the first area 112a toward the second area 112b, the flow cross-sectional area can be gradually increased, so that the change of the gas flow velocity is relatively gentle, so that the gas can be better driven to flow out of the flow channel 112 during the flow of the electrolyte, so as to improve the efficiency of gas transmission in the electrolytic cell.

[0057] The guide surface 121 may be a plane or a curved surface, and has the characteristics of simple structure and easy processing, which is beneficial to reducing the manufacturing difficulty and production cost of the sub-plate 12 .

[0058] In another specific embodiment, Figure 3 As shown, along the thickness direction of the electrode plate, during the process of gas diffusion from the first region 112a toward the second region 112b, the flow cross-sectional area may suddenly increase, so as to promote the flow of electrolyte and gas along this direction in a sudden manner, which is beneficial to improving the mass transfer efficiency of the electrolytic cell.

[0059] In a specific embodiment, along the width direction of the electrode plate, the distance between two adjacent sub-plates 12 is L1, the distance between two adjacent ribs 111 is L2, and L1 and L2 satisfy 0.1≤L1 / L2≤0.9, and L1 satisfies 0.1mm≤L1.

[0060] In the embodiments of the present application, the ratio of L1 to L2 can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, etc.

[0061] When the ratio of the distance between two adjacent sub-plates 12 to the distance between two adjacent ribs 111 satisfies 0.1≤L1 / L2≤0.9, an obvious flow pressure difference can be formed between the first region 112a and the second region 112b along the thickness direction of the electrode plate, so that the gas at the membrane electrode can flow along the membrane electrode assembly 2 toward the plate body 1 under the action of the flow pressure difference, so as to avoid the accumulation of gas generated after electrolysis at the membrane electrode, reduce the possibility of gas aggregation effect at the membrane electrode, and thus help to improve the hydrogen production efficiency of the electrolyzer.

[0062] Among them, the distance L1 between two adjacent sub-plates 12 can be specifically 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, etc., to ensure that there is a gap between two adjacent sub-plates 12 to form the first region 112a of the flow channel 112, so that the membrane electrode assembly 2 and the flow channel 112 are always connected, so as to facilitate the diffusion and transmission of the electrolyte and the gas, thereby ensuring the stability and reliability of the electrolyzer during operation. Compared with the conventional flow channel 112, the present application can increase the overall flow cross-sectional area of ​​the flow channel 112 through the first region 112a to increase the flow rate of the electrolyte per unit time, so as to improve the efficiency of hydrogen production in the electrolyzer while improving the fluidity of the flow of the electrolyte and the gas in the flow channel 112.

[0063] In a specific implementation, along the thickness direction of the electrode plate, the thickness of the sub-plate 12 is H1, the thickness of the rib 111 is H2, and H1 and H2 satisfy 0.1≤H1 / H2≤1, and H1 satisfies 0.1mm≤H1≤5mm.

[0064] In the embodiment of the present application, the ratio of the thickness of the sub-plate 12 to the thickness of the rib 111 can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 1, etc.

[0065] When the ratio of the thickness of the sub-plate 12 to the thickness of the rib 111 satisfies 0.1≤H1 / H2≤1, the thickness of the sub-plate 12 is moderate, so that there can be a significant change in the flow cross-sectional area between the first area 112a and the second area 112b. The risk of low diffusion and transmission efficiency of the electrolyte and gas due to excessive thickness of the sub-plate 12 can also be avoided, which is beneficial to improving the hydrogen production efficiency of the electrolyzer while ensuring the stability and reliability of the electrolyzer during operation.

[0066] Among them, the thickness of the sub-plate 12 can be specifically 0.1mm, 0.3mm, 0.5mm, 0.7mm, 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc., so that the first area 112a of the flow channel 112 is within a suitable range, which is beneficial to improve the hydrogen production efficiency of the electrolyzer while avoiding the risk of excessive thickness and weight of the electrolyzer as a whole, so as to achieve the purpose of lightweight design of the electrolyzer.

[0067] In a specific embodiment, Figure 5 As shown, each rib 111 includes a first extension portion 111a, a second extension portion 111b and a main body portion 111c. Along the width direction of the electrode plate, the first extension portion 111a and the second extension portion 111b are connected to both sides of the main body portion 111c, and along the thickness direction of the electrode plate, the upper surfaces of the first extension portion 111a and the second extension portion 111b are flush with the upper surface of the main body portion 111c.

[0068] Along the width direction of the electrode plate, a first region 112 a of the flow channel 112 is formed between the first extension portion 111 a of the rib 111 and the second extension portion 111 b of the adjacent rib 111 , and a second region 112 b of the flow channel 112 is formed between two adjacent ribs 111 .

[0069] The first extension portion 111a, the second extension portion 111b and the main body portion 111c are an integrally formed structure.

[0070] In the embodiment of the present application, the flow channel 112 is formed by two adjacent ribs 111, so there is no need to set the sub-plate 12, which is conducive to reducing the input of production materials, so as to reduce the production cost of the plate body 1. At the same time, eliminating the sub-plate 12 is also conducive to reducing the thickness of the entire electrolytic cell and reducing the weight of the entire electrolytic cell, so as to achieve the purpose of lightweight design.

[0071] Specifically, the rib 111 includes a first extension portion 111a, a second extension portion 111b and a main body portion 111c that are connected. The main body portion 111c is raised relative to the main board 11. Along the width direction of the electrode plate, the first extension portion 111a and the second extension portion 111b are respectively connected to the two sides of the main body portion 111c, so that a first area 112a of the flow channel 112 can be formed between the first extension portion 111a of any rib 111 and the second extension portion 111b of the adjacent rib 111, and a second area 112b of the flow channel 112 is formed between two adjacent ribs 111.

[0072] At the same time, along the thickness direction of the electrode plate, the upper surfaces of the first extension portion 111a and the second extension portion 111b are flush with the upper surface of the main body 111c, so that the upper surfaces of each rib 111 can be in the same plane, thereby ensuring that the plate body 1 and the membrane electrode assembly 2 are tightly fitted during the lamination process, which is beneficial to improving the overall sealing of the electrolytic cell and ensuring the safety and reliability of the electrolytic cell during operation.

[0073] In addition, the first extension portion 111 a , the second extension portion 111 b and the main body portion 111 c are an integrally formed structure, which is beneficial to improving the connection reliability among the three and improving the overall structural strength of the board body 1 .

[0074] In a possible implementation manner, the first extension portion 111 a , the second extension portion 111 b , and the main body portion 111 c may be formed by casting.

[0075] An embodiment of the present application further provides an electrolytic cell, which includes a pole plate and a membrane electrode assembly 2. The pole plate body 1 and the membrane electrode assembly 2 are stacked along the thickness direction of the electrolytic cell, wherein the pole plate adopts any of the pole plates described above.

[0076] In the embodiment of the present application, the membrane electrode assembly 2 includes an electrode plate, a diffusion layer and a membrane electrode. Along the thickness direction of the electrolytic cell, the diffusion layer is located between the electrode plate and the membrane electrode. The diffusion layer has a transmission channel connecting the membrane electrode and the flow channel 112. The transmission channel is used to transmit electrolyte and gas to ensure the stability and reliability of the electrolytic cell during operation.

[0077] During the operation of the electrolyzer, water flowing into the electrolyzer flows into the flow channels 112 in the flow field area through the water inlet cavity, so that the water flows in the flow channels 112 and undergoes oxidation-reduction reactions, thereby generating hydrogen and oxygen at the membrane electrode. After the water flows out of the flow channels 112 in the flow field area, it flows out of the electrolyzer through the water outlet cavity, thereby realizing the production of hydrogen by electrolyzing water in the electrolyzer.

[0078] Specifically, during the process of water flowing in the flow channel 112 , at least part of the water can diffuse along the plate body 1 toward the membrane electrode assembly 2 , so as to cause a redox reaction at the membrane electrode and generate gas.

[0079] Since the flow channel 112 is divided into a first area 112a and a second area 112b which are interconnected, the first area 112a is located on a side of the second area 112b close to the membrane electrode, and the cross-sectional area of ​​the first area 112a is smaller than the cross-sectional area of ​​the second area 112b, so that a flow pressure difference can be formed between the first area 112a and the second area 112b located in the flow channel 112, so that the gas located at the membrane electrode can flow along the membrane electrode assembly 2 toward the plate body 1 under the action of the flow pressure difference, so as to avoid the accumulation of gas generated after electrolysis at the membrane electrode, thereby reducing the possibility of gas aggregation effect at the membrane electrode, which is beneficial to improving the hydrogen production efficiency of the electrolyzer.

[0080] In a possible embodiment, the water inlet cavity and the water outlet cavity can be set to a rectangular structure, and the water inlet cavity and the water outlet cavity are respectively located on a diagonal line of the plate body 1, so that during the operation of the electrolyzer, water flows into the plate body 1 from the water inlet cavity to undergo an oxidation-reduction reaction, and flows out of the plate body 1 from the water outlet cavity. The diagonal arrangement of the water inlet cavity and the water outlet cavity can promote the convection effect of water in the flow field area of ​​the plate body 1, which is beneficial to improving the hydrogen production efficiency of the electrolyzer.

[0081] In a possible embodiment, the plate body 1 is also provided with a distribution area, which is located between the water inlet cavity and the flow field area along the length direction of the electrode plate. The distribution area is used to evenly distribute the water flowing out of the water inlet cavity to each flow channel 112 in the flow field area, so that a uniform electrochemical reaction can occur in the flow field area, avoiding the risk of local reaction in the plate body 1 due to uneven distribution, which is beneficial to improving the stability and reliability of the electrolytic cell during operation.

[0082] In a possible embodiment, the plate body 1 is also provided with a confluence area, which is located between the water outlet cavity and the flow field area along the length direction of the electrode plate. The confluence area is used to collect the water flowing out of the flow field area and introduce it into the water outlet cavity at the same time to ensure that the water can flow out of the electrolytic cell stably and smoothly for the next recycling.

[0083] In a possible embodiment, both the distribution area and the confluence area may include a plurality of protrusions, and the plurality of protrusions are spaced apart along the length and width directions of the electrode plate. Specifically, the protrusions located in the distribution area can adjust the path and direction of water flow, thereby effectively distributing the water flowing out of the water inlet cavity to each flow channel 112, so as to further improve the uniformity of water distribution in the flow field area, which is conducive to improving the flow efficiency of water, thereby improving the hydrogen production efficiency of the electrolyzer; the protrusions located in the confluence area can guide and merge the water flowing out of each flow channel 112, reduce the flow resistance, improve the flow efficiency, and enable it to flow more smoothly into the water outlet cavity, which is conducive to improving the recovery efficiency.

[0084] The above describes in detail the structure, features and effects of the present application based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present application, but the present application does not limit the scope of implementation to what is shown in the drawings. Any changes made in accordance with the concept of the present application, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the description and drawings, should be within the protection scope of the present application.

Claims

1. A plate, characterized in that: The electrode plate comprises: A plate body, wherein the plate body has a flow field area, wherein the flow field area is provided with a plurality of convex ribs, wherein the plurality of convex ribs extend along the length direction of the electrode plate and are spaced apart along the width direction of the electrode plate, and a flow channel is formed between two adjacent convex ribs; Wherein, along the thickness direction of the electrode plate, the flow channel includes a first region and a second region that are connected, the first region is located on a side of the second region close to the membrane electrode assembly, and the cross-sectional area of ​​the first region is smaller than that of the second region.

2. The electrode plate according to claim 1, characterized in that: The cross-sectional area of ​​the first region is S1, the cross-sectional area of ​​the second region is S2, and S1 and S2 satisfy 0.1≤S1 / S2≤0.

9.

3. The electrode plate according to claim 1, characterized in that: The plate body includes a main plate and a plurality of sub-plates, along the thickness direction of the electrode plate, each convex rib is protruding relative to the main plate, each sub-plate is respectively connected to a side of each convex rib away from the main plate, and each convex rib is located within the projection range of each sub-plate; Along the width direction of the electrode plate, there is a gap between two adjacent sub-plates, the gap forms the first area of ​​the flow channel, and the second area of ​​the flow channel is formed between two adjacent convex ribs.

4. The electrode plate according to claim 3, characterized in that: Along the width direction of the electrode plate, both ends of the auxiliary plate are provided with guide surfaces, and along the thickness direction of the electrode plate, the guide surface is located on the side of the auxiliary plate facing the main plate; Wherein, the guide surface is a plane or a curved surface.

5. The electrode plate according to claim 3, characterized in that: Along the width direction of the electrode plate, the distance between two adjacent sub-plates is L1, the distance between two adjacent convex ribs is L2, and L1 and L2 satisfy 0.1≤L1 / L2≤0.9, and L1 satisfies 0.1mm≤L1.

6. The electrode plate according to claim 3, characterized in that: Along the thickness direction of the electrode plate, the thickness of the sub-plate is H1, the thickness of the convex rib is H2, and H1 and H2 satisfy 0.1≤H1 / H2≤1, and H1 satisfies 0.1mm≤H1≤5mm.

7. The electrode plate according to any one of claims 1 to 6, characterized in that: Each of the convex ribs comprises a first extension portion, a second extension portion and a main body portion, wherein along the width direction of the electrode plate, the first extension portion and the second extension portion are connected to both sides of the main body portion, and along the thickness direction of the electrode plate, the upper surfaces of the first extension portion and the second extension portion are flush with the upper surface of the main body portion; Along the width direction of the electrode plate, the first extension portion of the convex rib and the second extension portion of the adjacent convex rib form the first region of the flow channel, and the second region of the flow channel is formed between two adjacent convex ribs.

8. The electrode plate according to claim 7, characterized in that: The first extension portion, the second extension portion and the main body portion are an integrally formed structure.

9. An electrolytic cell, characterized in that: The electrolytic cell comprises: Plates; A membrane electrode assembly, wherein the membrane electrode assembly and the electrode plate are stacked in a thickness direction of the electrolytic cell; Wherein, the electrode plate adopts the electrode plate as described in any one of claims 1-8.

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