A flow channel structure of an alkaline electrolytic cell and an alkaline electrolytic cell

Abstract

The present invention relates to a flow channel structure of an alkaline electrolytic cell and an alkaline electrolytic cell, the flow channel structure comprises a plate body, the plate body is provided with an inlet end and an outlet end; a dotted spoiler structure unit is distributed on the plate body, the dotted spoiler structure unit forms a fluid flow channel on the plate body, the dotted spoiler structure unit comprises a first-level spoiler structure unit, a second-level spoiler structure unit, and a third-level spoiler structure unit, the first-level spoiler structure unit, the second-level spoiler structure unit and the third-level spoiler structure unit form a shunt flow channel on the plate body. The present invention promotes the lateral flow capacity and mass transfer rate of the electrolyte, effectively improves the flow uniformity of the electrolyte, makes the electrolyte fully utilized in the process of electrolysis, and effectively improves the electrolysis efficiency. And it can effectively discharge the gas generated by the electrolysis reaction, reduce the generation of local hot spots, and effectively improve the service life of the alkaline electrolytic cell.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen production by electrolysis of water, and particularly relates to a flow channel structure of an alkaline electrolytic cell and the alkaline electrolytic cell. Background Art

[0002] As a clean and efficient form of energy, hydrogen energy has great development potential. The popularization of hydrogen energy is expected to significantly reduce carbon dioxide emissions and alleviate global climate change. At present, the production, storage and transportation technologies of hydrogen energy are constantly improving, especially the water electrolysis hydrogen production technology has attracted much attention due to its environmental protection and high efficiency. Alkaline electrolyzer is the core equipment in alkaline water electrolysis hydrogen production technology. It has the advantages of low cost, high stability and long life, so it has been widely used in industrial hydrogen production.

[0003] However, how to further improve the hydrogen production efficiency of alkaline electrolyzers is one of the key research directions of alkaline water electrolysis technology. The main components of alkaline electrolyzers include plates, anodes, cathodes, diaphragms and gaskets. In addition to developing electrode materials with higher catalytic performance and thinner diaphragm materials to improve electrolysis efficiency, optimizing the flow channel structure on the plates can further reduce the reaction overpotential. The traditional alkaline electrolyzer flow channel design cannot meet the growing efficiency requirements. Improving the flow channel design to reduce the reflux area and improve the flow uniformity of the fluid has become a research hotspot.

[0004] The papillary flow channel structure in the traditional alkaline electrolyzer, namely the concave-convex sphere flow channel (CCSFC), usually includes a plurality of regularly arranged protrusions, which are hemispherical and evenly distributed inside the flow channel. The main function of the papillary is to change the flow trajectory of the fluid through physical obstacles and promote the uniform distribution of the electrolyte. Specifically, when the fluid flows between these papillary ridges, it has to bypass these protrusions due to the presence of the papillary ridges, thus generating a local turbulent effect. This turbulence can increase the contact area between the fluid and the electrode surface and improve the electrolysis efficiency. At the same time, the papillary flow channel design can also help reduce the accumulation of bubbles and avoid the electrode surface being covered by bubbles, thereby maintaining the stability and efficiency of the electrolysis process. Traditional flow channel structures also include regularly arranged square flow channels (SFC), regularly arranged diamond flow channels (DFC) and regularly arranged triangle flow channels (TFC).

[0005] Although the mastoid flow channel design improves the flow and mixing of the electrolyte to a certain extent, there are still some obvious problems in practical applications. First, the fixed shape and arrangement of the mastoids make it easy for the fluid to form local eddies and recirculation areas when bypassing these protrusions. Eddies and recirculation can cause the fluid to stagnate in some areas, reducing the electrolysis efficiency in these areas. In addition, local eddies may cause uneven concentration distribution of the electrolyte, further affecting the overall electrolysis performance. Second, the fluid flow in the mastoid flow channel is highly non-uniform. In some areas, the fluid may flow too fast, resulting in insufficient residence time of the electrolyte in these areas and inability to fully participate in the electrolysis reaction; while in other areas, the fluid flows too slowly, resulting in reduced electrolyte utilization in these areas. This flow non-uniformity not only affects the electrolysis efficiency, but may also make it difficult for bubbles accumulated on the electrode surface to fall off in time, further reducing the performance of the electrolyzer. In addition, due to the slow flow speed of the fluid in these areas, heat is difficult to transfer and diffuse quickly, resulting in local temperature increases. This local overheating phenomenon will not only reduce the stability of the electrolyte, but may also accelerate the corrosion and aging of the electrode materials, thus affecting the overall life and performance of the electrolyzer. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a flow channel structure of an alkaline electrolytic cell and an alkaline electrolytic cell, so that the flow in the flow channel of the alkaline electrolytic cell is evenly distributed, the electrolyte is fully utilized during the electrolysis process, the electrolysis efficiency is improved, the gas generated by the electrolysis reaction is effectively discharged, the generation of local hot spots is reduced, and the service life of the alkaline electrolytic cell is increased.

[0007] The present invention provides a flow channel structure of an alkaline electrolytic cell, which comprises a plate body, wherein the plate body is provided with an inlet end and an outlet end, and a fluid direction is formed from the inlet end to the outlet end; point-shaped spoiler structure units are distributed on the plate body, and the point-shaped spoiler structure units form a fluid flow channel on the plate body, and the point-shaped spoiler structure units comprise a first-level spoiler structure unit close to the inlet end, a second-level spoiler structure unit, and a third-level spoiler structure unit close to the outlet end, wherein the first-level spoiler structure unit comprises a plurality of first protruding structure units staggeredly distributed in a direction perpendicular to the fluid, the second-level spoiler structure unit is located between the first-level spoiler structure unit and the third-level spoiler structure unit, the second-level spoiler structure unit comprises a plurality of second protruding structure units staggeredly distributed with the first-level spoiler structure unit in a direction parallel to the fluid, and the third-level spoiler structure unit comprises a plurality of third protruding structure units. Through the first-level spoiler structure unit, several first protruding structure units are staggered in the direction perpendicular to the fluid, and the electrolyte entering from the inlet end is initially dispersed in multiple directions, thereby improving the lateral distribution capacity of the electrolyte, ensuring the longitudinal flow of the electrolyte, and promoting the lateral flow at the same time, so that the electrolyte begins to be initially shunted to the maximum extent after entering the fluid flow channel, and the shunting efficiency is high. When the electrolyte flows to the second-level spoiler structure unit through the first-level spoiler structure unit, since the second-level spoiler structure unit is staggered with the first-level spoiler structure unit in the direction parallel to the fluid, the second-level spoiler structure unit will shunt the electrolyte that was initially shunted from the first-level spoiler structure unit again, further promoting the lateral flow and increasing the longitudinal shunt. When the electrolyte flows to the third-level spoiler structure unit, the third-level spoiler structure unit shunts the electrolyte again, so that the electrolyte flowing into the inlet end is evenly distributed.

[0008] Preferably, the electrode plate is also provided with a plurality of mastoid flow disturbance areas, which are distributed in the point-shaped flow disturbance structure units, and each of the mastoid flow disturbance areas includes a plurality of mastoid structure units that are staggered with each other. The mastoid flow disturbance areas can be adapted to the arrangement of a plurality of electrolytic cells of different volumes, and the mastoid structure units in the mastoid flow disturbance areas are staggered with each other, so that the electrolyte can be dispersed more evenly.

[0009] Preferably, the third-stage flow-disturbing structure unit includes a plurality of protruding structure units that are staggered with the second-stage flow-disturbing structure units in a direction parallel to the fluid, which can further promote the lateral flow and make the electrolyte flowing into the inlet end more evenly distributed.

[0010] Preferably, the first protrusion structure unit, the second protrusion structure unit, and the third protrusion structure unit are any one of square protrusions, diamond protrusions, and triangular protrusions, or any combination thereof. The square protrusions, diamond protrusions, and triangular protrusions are flat plane interferences, which have a stronger flow disturbance effect on the electrolyte and can ensure that the electrolyte achieves a stronger lateral diversion.

[0011] Preferably, the first-stage flow-disturbing structural unit is a raised structural unit that is stepped and has two ends that rise toward the fluid inlet and is staggeredly distributed perpendicular to the fluid direction.

[0012] Preferably, the first protrusion structure unit is a square protrusion, the second protrusion structure unit is a square protrusion, and the third protrusion structure unit is a square protrusion.

[0013] Preferably, the first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; and the third protrusion structure unit is a square protrusion.

[0014] Preferably, the first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; and the third protrusion structure unit is a diamond-shaped protrusion.

[0015] Preferably, the first protrusion structure unit is a square protrusion, the second protrusion structure unit is a triangular protrusion, and the third protrusion structure unit is a diamond protrusion.

[0016] An alkaline electrolytic cell is provided with the above-mentioned flow channel structure.

[0017] The present invention has the following technical effects:

[0018] Through the first-level spoiler structure unit, several first protruding structure units are staggered in the direction perpendicular to the fluid, and the electrolyte entering from the inlet end is initially dispersed in multiple directions, thereby improving the lateral distribution capacity of the electrolyte, ensuring the longitudinal flow of the electrolyte, and promoting the lateral flow at the same time, so that the electrolyte begins to be initially shunted to the maximum extent after entering the fluid flow channel, and the shunting efficiency is high. When the electrolyte flows to the second-level spoiler structure unit through the first-level spoiler structure unit, since the second-level spoiler structure unit is staggered with the first-level spoiler structure unit in the direction parallel to the fluid, the second-level spoiler structure unit will shunt the electrolyte that was initially shunted from the first-level spoiler structure unit again, further promoting the lateral flow and increasing the longitudinal shunt. When the electrolyte flows to the third-level spoiler structure unit, the third-level spoiler structure unit shunts the electrolyte again, so that the electrolyte flowing into the inlet end is evenly distributed. The first-stage flow disturbance structural unit, the second-stage flow disturbance structural unit and the third-stage flow disturbance structural unit form a flow channel, which promotes the lateral flow capacity and mass transfer rate of the electrolyte, effectively improves the flow uniformity of the electrolyte, makes the electrolyte fully utilized in the electrolysis process, and effectively improves the electrolysis efficiency. In addition, due to the uniform flow distribution, the gas generated by the electrolysis reaction can be effectively discharged, and the generation of local hot spots can be reduced, thereby effectively improving the service life of the alkaline electrolytic cell.

[0019] 2. Since the first-level spoiler structure unit includes several first protruding structure units, the second-level spoiler structure unit includes several second protruding structure units, and the third-level spoiler structure unit includes several third protruding structure units, the first protruding structure units, the second protruding structure units, and the third protruding structure units can be freely arranged in rows and columns according to the needs of the electrolytic cell, the electrode plates can be fully utilized, the role of the point-shaped spoiler structure units can be brought into play, and the practicality is strong.

[0020] 3. The mastoid structural units in the mastoid disturbance zone are staggered with each other, so that the electrolyte can be dispersed more evenly and the utilization efficiency of the overall structure is improved.

[0021] 4. Multiple disturbance areas are formed on the electrode plate through the first-stage disturbance structure unit, the second-stage disturbance structure unit, the third-stage disturbance structure unit and the mastoid disturbance area, so that the electrolyte can complete multiple diversions when flowing from the inlet end to the outlet end, so that the electrolyte flow is evenly distributed in the flow channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of Embodiment 4 of the present invention;

[0026] Figure 5 The velocity cloud diagram of the electrolyte in the cathode flow channel of Examples 1-4 of the present invention;

[0027] Figure 6 Schematic diagram of the y coordinates of six xz sections of the flow channel in the electrolyzer model geometry of CCFSC;

[0028] Figure 7 is the flow uniformity coefficient (Uxz) of the six xz sections and the flow uniformity coefficient (Uxy) of the xy section in the middle of the flow channel of Comparative Examples 1-4;

[0029] Figure 8 is the flow uniformity coefficient (Uxz) of the six xz sections and the flow uniformity coefficient (Uxy) of the xy section in the middle of the flow channel of Examples 1-4;

[0030] Fig. 9 The average volume fraction of gas in the cathode and anode of the electrolytic cell with the flow channel structure of Comparative Examples 1-4 and Example 4;

[0031] Fig.10The highest temperature, the lowest temperature and the average temperature in the electrolytic cell diaphragm of the flow channel structure of Comparative Examples 1-4 and Example 4;

[0032] Fig.11 Polarization curves of the electrolytic cells with flow channel structures of Comparative Examples 1-4 and Example 4;

[0033] Fig.12 This is a schematic diagram of the structure of Embodiment 5 of the present invention;

[0034] Fig.13 This is a structural diagram of Embodiment 6 of the present invention;

[0035] Fig.14 This is a structural diagram of Example 7 of the present invention.

[0036] Illustrations: 1. Plate body; 11. Inlet end; 12. Outlet end; 2. First-stage spoiler structure unit; 3. Second-stage spoiler structure unit; 4. Third-stage spoiler structure unit; 5. Mastoid spoiler area. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings.

[0038] Example 1: Figure 1 As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a point-shaped spoiler structure unit is distributed on the plate body 1, and the point-shaped spoiler structure unit forms a fluid flow channel on the plate body 1, and the point-shaped spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 5 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 29 third convex structure units arranged in five rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped protrusion structure unit with both ends rising toward the fluid inlet end 11 and staggeredly distributed perpendicular to the fluid direction. The first protrusion structure unit is a square protrusion, the second protrusion structure unit is a square protrusion, and the third protrusion structure unit is a square protrusion.

[0039] Example 2: Figure 2As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a dotted spoiler structure unit is distributed on the plate body 1, and the dotted spoiler structure unit forms a fluid flow channel on the plate body 1, and the dotted spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 6 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 29 third convex structure units arranged in five rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped protrusion structure unit with both ends rising toward the fluid inlet end 11 and staggered distribution perpendicular to the fluid direction. The first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; the third protrusion structure unit is a square protrusion.

[0040] Example 3: Figure 3 As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a dotted spoiler structure unit is distributed on the plate body 1, and the dotted spoiler structure unit forms a fluid flow channel on the plate body 1, and the dotted spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 6 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 29 third convex structure units arranged in ten thousand rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped protrusion structure unit with both ends rising toward the fluid inlet end 11 and staggered distribution perpendicular to the fluid direction. The first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; the third protrusion structure unit is a diamond-shaped protrusion.

[0041] Example 4: Figure 4As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a dotted spoiler structure unit is distributed on the plate body 1, and the dotted spoiler structure unit forms a fluid flow channel on the plate body 1, and the dotted spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 8 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 29 third convex structure units arranged in five rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped protrusion structure unit with both ends rising toward the fluid inlet end 11 and staggeredly distributed perpendicular to the fluid direction. The first protrusion structure unit is a square protrusion, the second protrusion structure unit is a triangular protrusion, and the third protrusion structure unit is a diamond protrusion.

[0042] Example 5: Fig.12As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a dotted spoiler structure unit is distributed on the plate body 1, and the dotted spoiler structure unit forms a fluid flow channel on the plate body 1, and the dotted spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 8 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 80 third convex structure units arranged in eight rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped raised structure unit with both ends rising toward the fluid inlet end 11 and staggered distribution perpendicular to the fluid direction. The first raised structure unit has a square protrusion in the middle and diamond-shaped protrusions at both ends; the second raised structure unit is a diamond-shaped protrusion, and the third raised structure unit is a diamond-shaped protrusion. A mastoid flow-disturbing area 5 is also provided on the plate, and the mastoid flow-disturbing area 5 is distributed between the second-stage flow-disturbing structure unit and the third-stage flow-disturbing structure unit, and the mastoid flow-disturbing area 5 includes 53 mastoid structure units arranged in five rows and staggered distribution.

[0043] Example 6: Fig.13As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a dotted spoiler structure unit is distributed on the plate body 1, and the dotted spoiler structure unit forms a fluid flow channel on the plate body 1, and the dotted spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 8 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 49 third convex structure units arranged in five rows. The first-stage spoiler structure unit 2 is a raised structure unit with two ends that are stepped and rise upward toward the fluid inlet end 11 and are staggered perpendicular to the fluid direction. The first raised structure unit has a square protrusion in the middle and diamond-shaped protrusions at both ends; the second raised structure unit is a diamond-shaped protrusion, and the third raised structure unit is a diamond-shaped protrusion. Two mastoid spoiler areas 5 are also provided on the electrode plate, wherein one mastoid spoiler area 5 is distributed between the second-stage spoiler structure unit and the third-stage spoiler structure unit, and includes 53 mastoid spoiler units arranged in five rows and staggered with each other; the other mastoid spoiler area 5 is distributed in the third-stage spoiler structure unit, and includes 53 mastoid spoiler units arranged in five rows and staggered with each other.

[0044] Example 7: Fig.14As shown, a flow channel structure of an alkaline electrolytic cell includes a plate body 1, wherein the plate body 1 is provided with an inlet end 11 and an outlet end 12, and a fluid direction is formed from the inlet end 11 to the outlet end 12; a point-shaped spoiler structure unit is distributed on the plate body 1, and the point-shaped spoiler structure unit forms a fluid flow channel on the plate body 1, and the point-shaped spoiler structure unit includes a first-level spoiler structure unit 2 near the inlet end 11, a second-level spoiler structure unit 3, and a third-level spoiler structure unit 4 near the outlet end 12, the first-level spoiler structure unit 2 includes 5 first convex structure units arranged in a row and staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit 3 is located between the first-level spoiler structure unit 2 and the third-level spoiler structure unit 4, the second-level spoiler structure unit 3 includes 8 second convex structure units arranged in a row and staggered with the first-level spoiler structure unit 2 in a direction parallel to the fluid, and the third-level spoiler structure unit 4 includes 10 third convex structure units arranged in two rows. The first-stage flow-disturbing structure unit 2 is a stair-shaped raised structure unit with both ends rising toward the fluid inlet end 11 and staggered distribution perpendicular to the fluid direction. The first raised structure unit has a square protrusion in the middle and diamond-shaped protrusions at both ends; the second raised structure unit is a diamond-shaped protrusion, and the third raised structure unit is a diamond-shaped protrusion. A mastoid flow-disturbing area 5 is also provided on the plate, and the mastoid flow-disturbing area 5 is distributed between the second-stage flow-disturbing structure unit and the third-stage flow-disturbing structure unit, and the mastoid flow-disturbing area 5 includes 193 mastoid structure units arranged in seventeen rows and staggered distribution.

[0045] Comparative Example 1: A conventional alkaline electrolyzer having regularly arranged concave-convex sphere flow channels (Concave-Convex Sphere FlowChannel, CCSFC).

[0046] Comparative Example 2: A conventional alkaline electrolyzer with regularly arranged square flow channels (SFC).

[0047] Comparative Example 3: A conventional alkaline electrolytic cell with regularly arranged diamond flow channels (DFC).

[0048] Comparative Example 4: A conventional alkaline electrolytic cell with regularly arranged triangle flow channels (Triangle Flow Channel, TFC).

[0049] Test example: An electrolytic cell with the structure of Example 1, an electrolytic cell with the structure of Example 2, an electrolytic cell with the structure of Example 3, an electrolytic cell with the structure of Example 4, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4 of the same size were used as test examples. Hereinafter, the electrolytic cell with the structure of Example 1 is referred to as PPFC-1, the electrolytic cell with the structure of Example 2 is referred to as PPFC-2, the electrolytic cell with the structure of Example 3 is referred to as PPFC-3, the electrolytic cell with the structure of Example 4 is referred to as PPFC-4, Comparative Example 1 is referred to as CCFSC, Comparative Example 2 is referred to as SFC, Comparative Example 3 is referred to as DFC, and Comparative Example 4 is referred to as TFC.

[0050] Finite element software was used to study the effect of the flow channel structure on the flow rate and distribution uniformity of the electrolyte, gas content, temperature and polarization curve inside the test case.

[0051] 1. Flow uniformity comparison

[0052] Take the geometry of the electrolytic cell model of CCFSC as an example. Figure 6 As shown, six xz sections are selected to analyze the electrolyte flow state in different regions of the flow channel. The remaining test cases select the corresponding six xz sections to analyze the electrolyte flow state in different regions of the flow channel.

[0053] In order to quantify the flow uniformity of the electrolyte in different flow channel structures, the flow uniformity coefficient Uv was introduced. The smaller the Uv, the more uniform the electrolyte flow.

[0054] The flow uniformity coefficient Uv is expressed as:

[0055] .

[0056] like Figure 7 As shown, at y=-13.75mm near the inlet end 11, the four traditional flow channels of CCFSC, SFC, DFC, and TFC all show the greatest degree of flow distribution unevenness, which are 0.83, 0.76, 0.79, and 0.78, respectively. Due to the flow distribution unevenness near the inlet end 11, when the electrolyte flows in, the flow distribution of the electrolyte downstream is affected.

[0057] like Figure 5 ,like Figure 8As shown, compared with the four traditional flow channels of CCFSC, SFC, DFC and TFC, the flow uniformity coefficients of the PPFC-1, PPFC-2, PPFC-3 and PPFC-4 structures at the xz section at y=-13.75mm are greatly reduced, which are 0.74, 0.75, 0.72 and 0.68 respectively. When the electrolyte flows in, the electrolyte entering from the inlet end 11 is initially disturbed and dispersed in multiple directions by the five first protruding structure units in the first-stage disturbance structure units 2 that are staggered and distributed perpendicular to the fluid direction, thereby improving the lateral distribution capacity of the electrolyte to ensure the longitudinal flow of the electrolyte and promoting the lateral flow, thereby maximizing the initial diversion of the electrolyte after entering the fluid flow channel, and achieving high diversion efficiency.

[0058] The diamond-shaped protruding structure unit of the third-stage spoiler structure unit 4 reduces the flow uniformity coefficient on all xz planes and the flow uniformity coefficient on the xy plane compared to the square-shaped protruding structure unit.

[0059] The first-stage flow-turbulating structure unit 2 adopts a convex structure unit with square protrusions staggered perpendicular to the fluid direction to ensure the longitudinal flow of the electrolyte while promoting the lateral flow; the second-stage flow-turbulating structure unit 3 further divides the electrolyte to maximize the longitudinal flow. In addition, the third-stage flow-turbulating structure unit 4 is also crucial for uniform electrolyte flow distribution.

[0060] In the test example, PPFC-4 exhibited the lowest flow uniformity coefficient in all six xz planes and the central xy plane. The flow uniformity coefficient of PPFC-4 in the xy plane was 17.5% lower than that of CCSFC, 2.4% lower than that of SFC, 4.9% lower than that of DFC, and 12.3% lower than that of TFC. Therefore, the flow channel structure of Example 4 has the most uniform electrolyte distribution, and Example 4 is the best example.

[0061] 2. Gas content comparison

[0062] like Fig. 9 As shown in the figure, the volume fractions of hydrogen and oxygen in the PPFC-4 electrode are the lowest, which are 0.08956 and 0.0615 respectively. PPFC-4 has excellent gas discharge capacity, thus preventing gas accumulation on the electrode surface, which leads to a decrease in the electrochemical active area and an increase in the electrolyte mass transfer resistance, and can effectively improve the electrolysis efficiency.

[0063] 3. Temperature comparison

[0064] like Fig.10As shown in the figure, the average temperature of PPFC-4 is 354.73 K, which is only 1.58 K higher than the operating temperature of 353.15 K, and the maximum temperature is about 6 K lower than that of CCSFC. The average temperature of CCSFC is the largest, and its maximum temperature is 15 K higher than the operating temperature. PPFC-4 can effectively control the temperature, reduce local hot spots, and ensure that the electrolyzer can operate at close to the operating temperature, which can improve the stability and safety of the entire water electrolysis system.

[0065] 4. Polarization curve comparison

[0066] like Fig.11 As shown in Figure 1, at the same voltage, a higher current density means a greater hydrogen production rate and better electrolyzer performance. At low voltage, the difference in current density among all five electrolyzers is negligible. As the electrolyzer voltage increases, the effect of the flow channel structure on the electrochemical performance becomes more and more obvious. Fig.10 As shown in the figure, at the same voltage, the current density is ranked as follows: PPFC-4>DFC>SFC>TFC>CCSFC. At a voltage of 1.8 V, the current density of PPFC-4 is 8.1% higher than that of CCSFC, and at a voltage of 2 V, the current density of PPFC-4 is 10.7% higher than that of CCSFC. PPFC-4 has the best electrolyte flow uniformity, thus ensuring sufficient supply of reactants and effective removal of gases, so at the same current density, PPFC-4 has lower energy loss.

[0067] In summary, PPFC-4 has good electrolyte distribution uniformity and mass transfer performance. The first-level spoiler structure unit 2 in the inlet area of ​​PPFC-4 adopts a convex structure unit with square protrusions staggered perpendicular to the fluid direction, which enhances the lateral distribution ability of the electrolyte, and the second-level spoiler structure unit 3 triangular convex structure unit increases the flow rate of the electrolyte and increases the mass transfer rate of the electrolyte to the porous electrode. Due to the improvement of flow uniformity, PPFC-4 can more effectively discharge the gas produced by the reaction and reduce the generation of local hot spots in the electrolytic cell. PPFC-4 has a higher electrolyte mass transfer rate and can more effectively discharge bubbles, thereby reducing mass transfer resistance and ohmic loss. Therefore, PPFC-4 exhibits excellent electrochemical performance, thereby increasing the electrolysis reaction rate and reducing the energy consumption of the alkaline electrolytic cell.

[0068] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A flow channel structure of an alkaline electrolytic cell, characterized in that: It includes a plate body, the plate body is provided with an inlet end and an outlet end, and a fluid direction is formed from the inlet end to the outlet end; a dotted spoiler structure unit is distributed on the plate body, the dotted spoiler structure unit forms a fluid flow channel on the plate body, the dotted spoiler structure unit includes a first-level spoiler structure unit near the inlet end, a second-level spoiler structure unit, and a third-level spoiler structure unit near the outlet end, the first-level spoiler structure unit includes a plurality of first convex structure units staggered in a direction perpendicular to the fluid, the second-level spoiler structure unit is located between the first-level spoiler structure unit and the third-level spoiler structure unit, the second-level spoiler structure unit includes a plurality of second convex structure units staggered in a direction parallel to the fluid with the first-level spoiler structure unit, and the third-level spoiler structure unit includes a plurality of third convex structure units; The electrode plate is also provided with a plurality of mastoid flow disturbance areas, which are distributed in the point-shaped flow disturbance structure units, and each of the mastoid flow disturbance areas includes a plurality of mastoid structure units which are distributed in an interlaced manner.

2. The flow channel structure of an alkaline electrolytic cell according to claim 1, characterized in that: The third-stage spoiler structure unit includes a plurality of protruding structure units which are staggeredly distributed with the second-stage spoiler structure units in a direction parallel to the fluid.

3. The flow channel structure of an alkaline electrolytic cell according to claim 1, characterized in that: The first protrusion structure unit, the second protrusion structure unit and the third protrusion structure unit are any one of square protrusions, diamond protrusions and triangular protrusions or any mixture thereof.

4. The flow channel structure of an alkaline electrolytic cell according to claim 3, characterized in that: The first-stage flow-disturbing structural unit is a raised structural unit that is stepped and has an upward trend toward the fluid inlet at both ends and is staggeredly distributed perpendicular to the fluid direction.

5. The flow channel structure of an alkaline electrolytic cell according to claim 4, characterized in that: The first protrusion structure unit is a square protrusion, the second protrusion structure unit is a square protrusion, and the third protrusion structure unit is a square protrusion.

6. The flow channel structure of an alkaline electrolytic cell according to claim 4, characterized in that: The first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; and the third protrusion structure unit is a square protrusion.

7. The flow channel structure of an alkaline electrolytic cell according to claim 4, characterized in that: The first protrusion structure unit is a square protrusion; the second protrusion structure unit has diamond-shaped protrusions at both ends and a triangular protrusion in the middle; and the third protrusion structure unit is a diamond-shaped protrusion.

8. The flow channel structure of an alkaline electrolytic cell according to claim 4, characterized in that: The first protrusion structure unit is a square protrusion, the second protrusion structure unit is a triangular protrusion, and the third protrusion structure unit is a diamond protrusion.

9. An alkaline electrolytic cell, characterized in that: The alkaline electrolytic cell is provided with the flow channel structure according to any one of claims 1 to 8.

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