CN-121989512-A - Preparation method of gas diffusion layer substrate layer for fuel cell

CN121989512ACN 121989512 ACN121989512 ACN 121989512ACN-121989512-A

Abstract

The invention discloses a preparation method of a gas diffusion layer substrate layer for a fuel cell, which belongs to the technical field of fuel cells and comprises the following steps of S1, S2, S3, S4, S5, wherein a conductive hot melt adhesive is coated to perform multi-layer lamination, S5, a gas diffusion layer substrate layer is obtained through hot-pressing compounding, the core-shell structure film of a core layer polymer fiber and a shell conductive carbon fiber is firstly obtained through coaxial electric spinning of an electrostatic spinning injection pump, then a plurality of layers of core-shell structure films are adhered through the conductive hot melt adhesive, and then the gas diffusion layer substrate layer is obtained through hot-pressing compounding.

Inventors

SUN MAOJIN
SUN LUYI
HU YANZHAO
ZHANG FEILONG
XU XIAO

Assignees

深圳市融美科技有限公司

Dates

Publication Date: 20260508
Application Date: 20240529

Claims (10)

1. A method of preparing a gas diffusion layer substrate layer for a fuel cell, comprising the steps of: S1, adding polymers into a solvent according to a proportion, and uniformly mixing to obtain a polymer spinning solution; S2, adding conductive carbon materials into a solvent according to a proportion, and uniformly mixing to obtain a conductive liquid; S3, placing the polymer spinning solution and the conductive liquid in an electrostatic spinning injection pump for coaxial electrospinning to obtain a core-shell structure film with a core layer of polymer fibers and a shell layer of conductive carbon fibers; S4, carrying out multi-layer superposition on the obtained core-shell structure films, wherein conductive hot melt adhesive is uniformly coated between two adjacent core-shell structure films; and S5, placing the multi-layer stacked prefabricated products in a hot press for hot-pressing and compounding to obtain conductive carbon paper, namely preparing a substrate layer of the fuel cell gas diffusion layer.
2. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S1, the polymer is any one of polyacrylonitrile powder, polyvinyl alcohol powder, polyvinylpyrrolidone powder, and polypropylene powder.
3. The method of preparing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S2, the conductive carbon material is one or more of carboxylated conductive carbon nanotubes, graphite emulsion, activated carbon, graphene and carbon black.
4. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein the solvent is any one of an N, N-dimethylformamide solution and an N-methylpyrrolidone solution in the step S1 and the step S2.
5. The method for preparing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S1, the polymer addition amount of the polymer spinning solution is 10% -15% of the mass fraction of the polymer spinning solution.
6. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S2, the conductive carbon material of the conductive liquid is added in an amount of 5 to 10% by mass of the conductive liquid.
7. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S3, parameters of the coaxial electrospinning are respectively set to negative pressure-2 KV, positive pressure 10KV-12KV, humidity 30% -50%, flow rate 1ml/h, and temperature 27 ℃.
8. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S4, the number of layers of the core-shell structure film is 2 to 8.
9. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S4, the conductive hot melt adhesive is any one of conductive silver paste, graphite conductive adhesive and epoxy conductive adhesive.
10. The method of manufacturing a gas diffusion layer substrate layer for a fuel cell according to claim 1, wherein in the step S5, parameters of the hot press are set to 120-300 ℃ and 2-30MPa, respectively, and the hot press time is 10-60min.

Description

Preparation method of gas diffusion layer substrate layer for fuel cell Technical Field The invention belongs to the technical field of fuel cells, and particularly relates to a preparation method of a gas diffusion layer substrate layer for a fuel cell. Background Proton exchange membrane fuel cells, i.e., hydrogen fuel cells, have been attracting attention due to their high efficiency, environmental friendliness, mild operating conditions, and the like. The proton exchange membrane fuel cell is composed of flow field plates, gas diffusion layers, microporous layers, catalytic layers, proton exchange membranes and other components, and can be used for vehicles such as electric automobiles, electric bicycles, electric tricycles and small-sized power stations and the like. The gas diffusion layer between the flow field plate and the catalytic layer plays roles of conducting electricity, supporting a membrane electrode, transferring mass and managing water in the proton exchange membrane fuel cell, when the proton exchange membrane fuel cell works, reaction gas is transferred to the catalytic layer through the gas diffusion layer, water generated by the catalytic layer is discharged through the gas diffusion layer, the mass transfer of the reaction gas and the discharge of the water directly influence the electrode performance of the membrane, poor gas mass transfer and water management capacity can lead to the reduction of the membrane electrode performance, at present, the gas diffusion layer is usually formed by a basal layer and a microporous layer, wherein the basal layer is generally made of carbon paper or carbon cloth, but the carbon paper prepared by the steps of raw material preparation, beating paper making, dipping, solidification, carbonization, graphitization treatment and the like at present has the defects of low strength, high brittleness, high processing cost, complex preparation process and the like in the operation process. In view of this, a method for preparing a gas diffusion layer substrate layer for a fuel cell is designed to solve the above problem of brittleness of carbon paper while simplifying the preparation method. Disclosure of Invention To solve the problems set forth in the background art. The invention provides a preparation method of a gas diffusion layer substrate layer for a fuel cell, which has the characteristics of flexibility, excellent conductive performance, excellent mechanical performance, simple preparation process and low production cost. In order to achieve the above purpose, the invention provides a preparation method of a gas diffusion layer substrate layer for a fuel cell, comprising the following steps: S1, adding polymers into a solvent according to a proportion, and uniformly mixing to obtain a polymer spinning solution; S2, adding conductive carbon materials into a solvent according to a proportion, and uniformly mixing to obtain a conductive liquid; S3, placing the polymer spinning solution and the conductive liquid in an electrostatic spinning injection pump for coaxial electrospinning to obtain a core-shell structure film with a core layer of polymer fibers and a shell layer of conductive carbon fibers; S4, carrying out multi-layer superposition on the obtained core-shell structure films, wherein conductive hot melt adhesive is uniformly coated between two adjacent core-shell structure films; and S5, placing the multi-layer stacked prefabricated products in a hot press for hot-pressing and compounding to obtain conductive carbon paper, namely preparing a substrate layer of the fuel cell gas diffusion layer. Further, in the step S1, the polymer is any one of polyacrylonitrile powder, polyvinyl alcohol powder, polyvinylpyrrolidone powder and polypropylene powder. Further, in the step S2, the conductive carbon material is one or more of carboxylated conductive carbon nanotubes, graphite emulsion, activated carbon, graphene and carbon black. Further, in the step S1 and the step S2, the solvent is any one of an N, N-dimethylformamide solution and an N-methylpyrrolidone solution. Further, in the step S1, the polymer addition amount of the polymer spinning solution is 10% -15% of the mass fraction of the polymer spinning solution. Further, in the step S2, the addition amount of the conductive carbon material of the conductive liquid is 5% -10% of the mass fraction of the conductive liquid. Further, in the step S3, parameters of coaxial electrospinning are respectively set to be negative pressure-2 KV, positive pressure 10KV-12KV, humidity 30% -50%, flow rate 1ml/h and temperature 27 ℃. Further, in the step S4, the number of layers of the core-shell structure film is 2-8. Further, in the step S4, the conductive hot melt adhesive is any one of conductive silver paste, graphite conductive adhesive and epoxy conductive adhesive. Further, in the step S5, parameters of the hot press are set to 120-300 ℃ and 2-30Mpa respectively, and the hot press time is 10-60min.