CN-122013212-A - Proton exchange membrane electrolytic cell of novel flow field and application method thereof

CN122013212ACN 122013212 ACN122013212 ACN 122013212ACN-122013212-A

Abstract

The invention belongs to the field of hydrogen production by water electrolysis of a proton exchange membrane, and relates to a novel proton exchange membrane electrolytic tank of a flow field and a use method thereof. The anode bipolar plate comprises an anode bipolar plate, an anode diffusion layer, an anode catalytic layer, a proton exchange membrane, a cathode catalytic layer, a cathode diffusion layer and a cathode bipolar plate which are sequentially stacked from an anode to a cathode, wherein an anode runner is formed in the inner side of the anode bipolar plate and is in contact with the outer surface of the anode diffusion layer, a cathode runner is formed in the inner side of the cathode bipolar plate and is in contact with the outer surface of the cathode diffusion layer, a plurality of protruding structures are arranged on a runner substrate of the anode runner, and the protruding structures are cylinders with regular hexagon cross section outlines. The invention obviously improves the uniformity of the hydrothermal distribution in the flow field, reduces the phenomena of air blockage and concentration polarization, and improves the uniformity of current density distribution and the electrochemical reaction efficiency.

Inventors

WANG ZIHENG
ZHAO YONG
WANG TUANJIE
XIE XIAOJUN
TONG BO
TAN ZENGQIANG
Fan Weizhe

Assignees

西安热工研究院有限公司

Dates

Publication Date: 20260512
Application Date: 20260122

Claims (10)

1. The proton exchange membrane electrolyzer of a new type flow field, characterized by, include from positive pole to the positive pole bipolar plate (1), positive pole diffusion layer (3), positive pole catalytic layer (4), proton exchange membrane (5), negative pole catalytic layer (6), negative pole diffusion layer (7) and negative pole bipolar plate (9) that the cathodic direction stacks up and sets up sequentially; An anode runner (2) is arranged on the inner side of the anode bipolar plate (1), and the anode runner (2) is in contact with the outer surface of the anode diffusion layer (3); A cathode runner (8) is arranged on the inner side of the cathode bipolar plate (9), and the cathode runner (8) is contacted with the outer surface of the cathode diffusion layer (7); the anode flow channel (2) is characterized in that a plurality of protruding structures (10) are arranged on a flow channel substrate, the protruding structures (10) are cylinders with regular hexagonal cross section outlines, and the protruding structures (10) are arranged on the flow channel substrate in a regular array.
2. A novel flow field proton exchange membrane electrolyzer as claimed in claim 1, characterized in that the raised structures (10) are regular hexagonal prisms.
3. The proton exchange membrane electrolyzer of a novel flow field according to claim 2, characterized in that the regular hexagonal prism has a length of 0.2mm to 0.25mm.
4. A novel flow field proton exchange membrane electrolyzer as claimed in claim 3, wherein the regular hexagonal prism has a length of 0.23mm.
5. The proton exchange membrane electrolyzer of a novel flow field according to claim 2, characterized in that the distance between adjacent regular hexagonal prisms is 0.2 mm-0.25 mm.
6. A novel flow field proton exchange membrane electrolyzer as claimed in claim 5, wherein the spacing between adjacent regular hexagonal prisms is 0.23mm.
7. The proton exchange membrane electrolyzer of a novel flow field according to claim 2, characterized in that the height of the regular hexagonal prism is 0.8 mm-1.2 mm.
8. A novel flow field proton exchange membrane electrolyzer as claimed in claim 7, wherein the height of the regular hexagonal prism is 1.0mm.
9. A novel flow field proton exchange membrane electrolyzer as claimed in claim 1, characterized in that the channel base of the cathode channel (8) is also provided with a plurality of said raised structures (10).
10. The method for using a proton exchange membrane electrolyzer of a novel flow field according to any one of claims 1 to 9, characterized by comprising the following steps: introducing liquid water into the anode flow channel (2); Applying direct-current voltage to the anode bipolar plate (1) and the cathode bipolar plate (9) to enable the introduced liquid water to generate electrolytic reaction at the anode catalytic layer (4) to generate oxygen and protons; The generated protons are transmitted to the cathode catalytic layer (6) through the proton exchange membrane (5); Protons transported to the cathode catalytic layer (6) combine with electrons to generate hydrogen; Oxygen generated by the reaction is discharged from the anode flow channel (2), and hydrogen generated by the reaction is discharged from the cathode flow channel (8); In the anode flow channel (2), a flow field is guided by the convex structures (10) which are arranged in a regular array, so that the transmission of liquid water to the anode diffusion layer (3) is enhanced, and oxygen generated by the reaction is promoted to be discharged from the anode diffusion layer (3) to the center of the flow channel.

Description

Proton exchange membrane electrolytic cell of novel flow field and application method thereof Technical Field The invention belongs to the field of hydrogen production by water electrolysis of a proton exchange membrane, and relates to a novel proton exchange membrane electrolytic tank of a flow field and a use method thereof. Background The technology of hydrogen production by water electrolysis is widely focused as an important path for realizing green hydrogen production. The proton exchange membrane electrolytic cell is considered as one of ideal technical routes for adapting to the scale hydrogen production of renewable wave energy sources (such as wind power and photovoltaic) due to the outstanding advantages of compact structure, wide working load range, quick dynamic response, high energy conversion efficiency and the like. The technology adopts a solid proton exchange membrane as electrolyte, does not need to supplement liquid electrolyte, can directly decompose pure water to generate high-purity hydrogen and oxygen, is obviously superior to the traditional alkaline electrolytic tank in the aspects of system integration and operation flexibility, and has been developed in part of demonstration projects and commercial application. However, the large-scale popularization of proton exchange membrane electrolytic cells still faces the dual challenges of high manufacturing cost and insufficient durability of membrane electrodes. The structure and material characteristics of the core components such as the flow field, the diffusion layer, the catalytic layer and the like in the electrolytic cell directly influence the mass transfer efficiency, the current density distribution and the heat management performance of the reaction gas, so that the overall performance and the service life of the electrolytic cell are determined. Particularly, the design of the flow field structure is used as a key link for realizing the function of the bipolar plate, and has decisive effect on the uniform distribution and transportation of hydrogen, oxygen, liquid water and reaction heat. At present, a flow field is usually etched on the surface of a bipolar plate in a mode of alternately arranging channels and ridges, and the rationality of geometric parameters (such as width, depth, spacing and the like) of the flow field is directly related to the air bubble discharge efficiency, the hydration state of a membrane electrode and the contact resistance, so that the voltage efficiency and the long-term stability of the electrolytic cell are affected. In addition, the bipolar plate is used as a component with large weight and volume in the proton exchange membrane electrolyzer stack, and the material selection, the processing technology and the flow field configuration are important to reduce the system cost. When the existing flow field design is used for coping with the working condition of high current density, the problems of uneven distribution of local gas-liquid two-phase flow, reduced utilization rate of a catalytic layer and the like often occur, and further improvement of the performance of the electrolytic tank is limited. Disclosure of Invention The invention provides a novel proton exchange membrane electrolytic cell of a flow field and a use method thereof, which are used for solving the problems in the prior art, remarkably improving the uniformity of hydrothermal distribution in the flow field, reducing the phenomena of air blockage and concentration polarization, and improving the uniformity of current density distribution and the electrochemical reaction efficiency. In order to achieve the purpose, the invention is realized by adopting the following technical scheme: In a first aspect, the invention provides a proton exchange membrane electrolyzer of a novel flow field, comprising an anode bipolar plate, an anode diffusion layer, an anode catalytic layer, a proton exchange membrane, a cathode catalytic layer, a cathode diffusion layer and a cathode bipolar plate which are sequentially stacked from an anode to a cathode; An anode runner is formed on the inner side of the anode bipolar plate and is in contact with the outer surface of the anode diffusion layer; A cathode runner is arranged on the inner side of the cathode bipolar plate and is contacted with the outer surface of the cathode diffusion layer; the anode flow channel comprises a flow channel substrate, a plurality of convex structures, a plurality of anode flow channels and a cathode flow channel, wherein the flow channel substrate of the anode flow channel is provided with the convex structures, the convex structures are cylinders with regular hexagon cross section outlines, and the convex structures are arranged on the flow channel substrate in a regular array. Preferably, the convex structure is a regular hexagonal prism. Preferably, the length of the regular hexagonal prism is 0.2 mm-0.25 mm. Preferably, the regular hexagonal prism has a length o