Porous electrode base material and process for producing the same

Abstract

An electrode base material for solid polymer fuel cell that overcomes the problems of prior art and is most suitable for use in assembling of an inexpensive compact cell stack; and a process for producing the electrode base material. There is provided a porous electrode base material of <= 150 mum thickness, comprising carbon staple fibers of 3 to 9 mum diameter dispersed in random directions within a substantially two-dimensional plane, these carbon staple fibers bound to each other by an amorphous resin carbide, further these carbon staple fibers crosslinked to each other by a filamentous resin carbide. It is also intended to provide an electrode base material for solid polymer fuel cell that overcomes the problems of prior art, realizing low cost, smooth supply and discharge of gas and water for use in reaction and exertion of cell performance. Thus, further, there is provided a porous electrode base material, comprising carbon staple fibers of 3 to 9 mum diameter dispersed in random directions within a substantially two-dimensional plane, these carbon staple fibers bound to each other by an amorphous resin carbide, further these carbon staple fibers crosslinked to each other by a network resin carbide of <= 3 mum minimum fiber diameter.

Description

technical field [0001] The present invention relates to a porous electrode substrate and a manufacturing method thereof. Background technique [0002] The porous electrode substrate is a material located between the separator and the catalyst layer in the solid polymer fuel cell. The material is required not only to function as an electrical conductor between the separator and the catalyst layer, but also to distribute gases such as hydrogen and oxygen supplied from the separator to the catalyst layer, and to absorb water generated from the catalyst layer and function to discharge to the outside. Carbon materials are currently generally considered effective. [0003] Conventionally, in order to enhance the mechanical strength, methods such as finely bonding short carbon fibers and resin carbides have been used, but since the gas permeability decreases, the performance often decreases when it is installed in a fuel cell. On the other hand, if it is desired to maintain a la...

AI Technical Summary

Problems solved by technology

However, such a material with few pores of 10 μm or less has low water retention, so it is difficult to control moisture, and it is considered that the power generation of the fuel cell cannot be sufficiently performed.

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