Carbon fibre cloth for gaseous diffusion layer of fuel cell electrode

Abstract

The invention relates to carbon fiber paper for an electrode gas diffusion layer of a fuel cell, and is characterized in that carbon fibers are cut short, the length of the cut short carbon fibers is between 0.5mm and 5.0mm, and the average length thereof is between 1.0mm and 3.0mm; less than 1 percent of dispersant is used for dispersing the short carbon fibers into a water phase to form pulp stock, wherein the content of the carbon fiber is between 97.1 and 99.1 percent by weight percentage; and a carbon fiber paper material is prepared by a wet papermaking forming method. The length distribution of the short carbon fibers is between 0.5 and 5.0 millimeters, the average length thereof is between 1.0mm and 3.0mm, and the content thereof is 97.1 to 99.1 percent by weight percentage; the thickness of the carbon fiber paper is between 0.14mm and 0.22mm, the porosity is more than 70 percent, the volume density is 0.36-0.52 g / cm, the gas transmission rate is less than or equal to 50mmH, the electric conductivity passing through the carbon paper is less than or equal to 0.16OHMcm, the area weight is 40-80 g / m, and the specific resistance is 0.04-0.05 Omega.cm.

Description

technical field

[0001] The invention relates to an electrode material, in particular to a carbon fiber paper material suitable for a fuel cell electrode gas diffusion layer, and to a preparation method of the carbon fiber paper material. Background technique

[0002] The gas diffusion layer material plays a role in supporting the catalyst layer and stabilizing the electrode structure in the electrode. It also provides fuel gas channels, electron channels and drainage channels for the electrode reaction. The influence of different diffusion layer materials on the structure, manufacturing process and performance of the electrode Also vary. Carbon fiber paper (carbon paper), carbon cloth, non-woven fabric and carbon black paper are commonly used electrode materials.

[0003] At present, some gas diffusion layers use carbon paper, and some use carbon cloth materials. They not only have a uniform porous thin-layer structure, but also have good electrical conductivity, good chem...

Examples

example 1

[0031] Example 1: Select polypropylene nitrile-based carbon fiber, after a few seconds to a few minutes of air oxidation pretreatment, put it into a cutting machine to cut it short, so that its length is distributed between 0.5 mm and 5.0 mm. The specific distribution data is as follows:

[0032] 1 mm long accounted for 49%; 2 mm long accounted for 32%; 3 mm long accounted for 14%; 5 mm long accounted for 5%. Its average length is 1.8 mm.

[0033] Then put it into the water phase containing 0.5% dispersant, stir evenly to obtain papermaking slurry. Wherein the dispersant is polyvinyl alcohol.

[0034] Finally, the carbon fiber paper material is prepared by using the traditional wet papermaking molding method, and the carbon fiber paper material is obtained by pressing after drying. Some performance indicators of the carbon fiber paper material obtained in this example are as follows:

[0035] The area weight is 40g / m 2 ; Thickness 0.14mm; Porosity 80%; Density 0.36g / cm 3 ...

example 2

[0037] Select polypropylene nitrile-based carbon fiber, after air oxidation pretreatment for a few seconds to a few minutes, put it into a cutting machine to cut it short, so that its length is distributed between 0.5mm and 5.0mm, and the specific distribution data is as follows:

[0038] 1mm length accounted for 1%; 2mm length accounted for 54%; 3mm length accounted for 29%; 5mm length accounted for 6%. Its average length is 2.36 mm.

[0039] Then put it into the water phase containing 0.5% dispersant and stir evenly to obtain papermaking slurry. Wherein the dispersant is polyvinyl alcohol.

[0040] Finally, the carbon fiber paper material is prepared by using the traditional wet papermaking molding method, and the carbon fiber paper material is obtained by pressing after drying.

[0041] Some performance indicators of the carbon fiber paper material obtained in this example are as follows:

[0042] The area weight is 80g / m 2 ; Thickness 0.22mm; Porosity 70%; Density 0.52...

technical field

[0001] The invention relates to an electrode material, in particular to a carbon fiber paper material suitable for a fuel cell electrode gas diffusion layer, and to a preparation method of the carbon fiber paper material. Background technique

[0002] The gas diffusion layer material plays a role in supporting the catalyst layer and stabilizing the electrode structure in the electrode. It also provides fuel gas channels, electron channels and drainage channels for the electrode reaction. The influence of different diffusion layer materials on the structure, manufacturing process and performance of the electrode Also vary. Carbon fiber paper (carbon paper), carbon cloth, non-woven fabric and carbon black paper are commonly used electrode materials.

[0003] At present, some gas diffusion layers use carbon paper, and some use carbon cloth materials. They not only have a uniform porous thin-layer structure, but also have good electrical conductivity, good chem...

Examples

example 1

[0031] Example 1: Select polypropylene nitrile-based carbon fiber, after a few seconds to a few minutes of air oxidation pretreatment, put it into a cutting machine to cut it short, so that its length is distributed between 0.5 mm and 5.0 mm. The specific distribution data is as follows:

[0032] 1 mm long accounted for 49%; 2 mm long accounted for 32%; 3 mm long accounted for 14%; 5 mm long accounted for 5%. Its average length is 1.8 mm.

[0033] Then put it into the water phase containing 0.5% dispersant, stir evenly to obtain papermaking slurry. Wherein the dispersant is polyvinyl alcohol.

[0034] Finally, the carbon fiber paper material is prepared by using the traditional wet papermaking molding method, and the carbon fiber paper material is obtained by pressing after drying. Some performance indicators of the carbon fiber paper material obtained in this example are as follows:

[0035] The area weight is 40g / m 2 ; Thickness 0.14mm; Porosity 80%; Density 0.36g / cm 3 ...

example 2

[0037] Select polypropylene nitrile-based carbon fiber, after air oxidation pretreatment for a few seconds to a few minutes, put it into a cutting machine to cut it short, so that its length is distributed between 0.5mm and 5.0mm, and the specific distribution data is as follows:

[0038] 1mm length accounted for 1%; 2mm length accounted for 54%; 3mm length accounted for 29%; 5mm length accounted for 6%. Its average length is 2.36 mm.

[0039] Then put it into the water phase containing 0.5% dispersant and stir evenly to obtain papermaking slurry. Wherein the dispersant is polyvinyl alcohol.

[0040] Finally, the carbon fiber paper material is prepared by using the traditional wet papermaking molding method, and the carbon fiber paper material is obtained by pressing after drying.

[0041] Some performance indicators of the carbon fiber paper material obtained in this example are as follows:

[0042] The area weight is 80g / m 2 ; Thickness 0.22mm; Porosity 70%; Density 0.52...