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The proton exchange membrane fuel cell (PEMFC) as an efficient and environment-friendly power generation device to get the attention of national governments and research institutions. In the various components of the PEMFC, carbon paper as the base material of the gas diffusion layer (GDL), not only acts as a support for the catalyst layer to stabilize the role of the electrode structure, and also bear the gas passage for the electrode reaction, the electron ducts and drainage channels, such as multiple The task is one of the key components that affect the electrode performance. Therefore, the study and the preparation of high-performance carbon paper, to improve the efficiency of the PEMFC and accelerate the commercialization process has important significance. In this experiment, the dry preparation of polyacrylonitrile (PAN)-based carbon fiber body as raw materials, chemical vapor deposition (CVD), dip molded, dip molded composite CVD process three different process routes prepared for PEMFC carbon paper , and its structure, the degree of graphitization, surface resistivity, gas permeation speed, the battery performance curve analysis, the results showed that: (1) using the CVD process Preparation of carbon paper between the fibers tightly, strengthen the energy conduction, thereby improve the conductive properties of the carbon paper, carbon paper after graphitization surface resistivity was 33.3-34.9mΩ · cm. CVD obvious effect of pores filled with carbon paper, after CVD carbon paper thickness is 889μm, the density of carbon paper 0.125g · cm-3 requirements density less than the carbon paper. (2) using a the impregnated molding process for preparing carbon paper, the molding pressure and the molding temperature is an important factor affecting the molding process, the carbon paper thickness and density of the gas permeation rate, the surface resistivity has a significant impact. The selection of the modified phenolic resin as impregnating agent, at a temperature of 150 ° C, pressure of 4 MPa dwell 1H prepared a thickness of 183μm, and a density of 0.49g.cm-3, and a gas permeation speed 4498ml · mm/cm2 · hr · mmAq the surface resistivity of 16.9mΩ the · cm carbon paper, carbon paper overall performance. (3) using the the dip molded CVD composite technology can be continuous and uniform layer of pyrolytic carbon, is formed in the surface of the carbon paper enhances the binding of the fibers and the matrix, to reduce the crack defects strengthen the current conduction. Toray carbon paper horizontal and vertical surface resistance of 0.43Ω and 0.70Ω homemade carbon paper face less resistance between the 0.21-0.45Ω, and horizontal and vertical surface resistance difference. (4) prepared density of 0.58 g.cm-3 carbon paper impregnated composite molding and CVD process, the battery performance is better than the carbon paper used in smaller intake humidity Toray carbon paper. In conditions of low intake air humidity RH60%, corresponding to the low current density 0.5A/cm2 Toray carbon paper PEMFC, the output voltage is 0.67V, the PEMFC install this experimental carbon paper output voltage as 0.7V; corresponding to a high current density of 2.0A/cm2, Toray carbon paper PEMFC output voltage of 0.28V, PEMFC install this experimental carbon paper output voltage is 0.38V.
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