Abstract: In a method of manufacturing a fluid diffusion layer for a solid polymer electrolyte fuel cell, a surface of the fluid diffusion layer is abraded so that the topography of the fluid diffusion layer surface is rendered more uniform. The fluid diffusion layer comprises a porous substrate, and may also comprise a carbon-containing sublayer, as well as hydrophobic material. The particles formed by the abrading operation may be deposited into at least some of the pores of the substrate to form a support structure for the direct depositing of a catalyst onto the abraded surface.

Abstract: The present methods make fluid diffusion layers having reduced surface roughness. The methods used for adhering the loading material to the substrate surface can reduce the average surface roughness of the fluid diffusion layers, thereby reducing leaks in and damage to ion exchange membranes. When fluid diffusion layers and electrodes having reduced surface roughness are employed in membrane electrode assemblies, better reliability and performance are obtained. A method of calculating the surface roughness of a fluid diffusion layer may be used.

Abstract: Fluid diffusion layers with favorable mechanical and electrical properties are prepared for fuel cell electrodes by impregnating a porous carbonaceous web with a carbonizable polymer having pyrrolidone functionality and then carbonizing the pyrrolidone polymer. The polymer having pyrrolidone functionality is stabilized against vaporization by use of an oxidization step prior to carbonization. The fluid diffusion layers are particularly suitable for use as gas diffusion layers in solid polymer electrolyte fuel cells.

Abstract: Fluid diffusion layers with favorable mechanical and electrical properties are prepared for fuel cell electrodes by impregnating a porous carbonaceous web with a carbonizable polymer having pyrrolidone functionality and then carbonizing the pyrrolidone polymer. The polymer having pyrrolidone functionality is stabilized against vaporization by use of an oxidization step prior to carbonization. The fluid diffusion layers are particularly suitable for use as gas diffusion layers in solid polymer electrolyte fuel cells.

Abstract: A transducer mounting device comprised of a monolith of moldable material overlying and supporting a self-tapping screw at one end for coupling to a target such as a machine casing or bearing housing and a fabricated insert at an opposite end for mating with a monitoring transducer. In a further preferred form a transducer mounting device is comprised of a preform including an internal cavity overlying a magnetic component, an adhesive interposed between the magnetic component and a target such as a machine casing or bearing housing at one end for magnetically and adhesively bonding said preform to the target and a threaded member disposed at an opposite end of the preform for mating with a monitoring transducer.

Abstract: A transducer mounting device comprised of a monolith of moldable material overlying and supporting a self-tapping screw at one end for coupling to a target such as a machine casing or bearing housing and a fabricated insert at an opposite end for mating with a monitoring transducer. In a further preferred form a transducer mounting device is comprised of a preform including an internal cavity overlying a magnetic component, an adhesive interposed between the magnetic component and a target such as a machine casing or bearing housing at one end for magnetically and adhesively bonding said preform to the target and a threaded member disposed at an opposite end of the preform for mating with a monitoring transducer.

Abstract: In a method of manufacturing a fluid diffusion layer for a solid polymer electrolyte fuel cell, a surface of the fluid diffusion layer is abraded so that the topography of the fluid diffusion layer surface is rendered more uniform. The fluid diffusion layer comprises a porous substrate, and may also comprise a carbon-containing sublayer, as well as hydrophobic material. The particles formed by the abrading operation may be deposited into at least some of the pores of the substrate to form a support structure for the direct depositing of a catalyst onto the abraded surface.

Abstract: The present methods make fluid diffusion layers having reduced surface roughness. The methods used for adhering the loading material to the substrate surface can reduce the average surface roughness of the fluid diffusion layers, thereby reducing leaks in and damage to ion exchange membranes. When fluid diffusion layers and electrodes having reduced surface roughness are employed in membrane electrode assemblies, better reliability and performance are obtained. A method of calculating the surface roughness of a fluid diffusion layer may be used.

Abstract: Fluid diffusion layers with favorable mechanical and electrical properties are prepared for fuel cell electrodes by impregnating a porous carbonaceous web with a carbonizable polymer having pyrrolidone functionality and then carbonizing the pyrrolidone polymer. The polymer having pyrrolidone functionality is stabilized against vaporization by use of an oxidization step prior to carbonization. The fluid diffusion layers are particularly suitable for use as gas diffusion layers in solid polymer electrolyte fuel cells.