NOVELTY - A fuel cell gas diffusion layer (140, 150) is manufactured by: extruding a carbonaceous material through openings in a die to form carbonaceous filaments; contacting the carbonaceous filaments with a gas stream to stretch the carbonaceous filaments, forming stretched carbonaceous filaments; and forming the stretched carbonaceous filaments into a sheet, forming at least a portion of the fuel cell gas diffusion layer.    USE - The invention is for manufacture of fuel cell gas diffusion layer used in a membrane electrode assembly, useful in a fuel cell (claimed), used to convert chemical energy to electrical energy.    ADVANTAGE - The invention has reduced number of steps, compared to methods of making a gas diffusion layer that does not contain melt blown filaments. Using melt blown filaments in the gas diffusion layer can allow the gas diffusion layer to be prepared without forming fibers, without cutting fibers, without dispersing fibers in water, and/or without forming paper. This reduces the cost and/or complexity of the process, and reduces the possibility of impurity introduction into the gas diffusion layer. The inventive gas diffusion layer exhibits desirable levels of flexibility, strength, in-plane resistivity, through-plane resistivity, porosity, and chemical inertness.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a membrane electrode assembly comprising a first and a second catalyst layer (120, 130); a solid electrolyte (110); a first gas diffusion layer comprising a first substrate having a surface, and a first sheet of melt blown carbonaceous filaments on the surface of the first substrate; and a second gas diffusion layer; and    (2) a fuel cell (100) comprising a first and a second flow plate (160, 170), and a membrane electrode assembly between the first and second flow plates.    DESCRIPTION OF DRAWING(S) - The figure is a cross-sectional view of a fuel cell.    Fuel cell (100)    Solid electrolyte (110)    First and second catalyst layer (120, 130)    Gas diffusion layer (140, 150)    First and second flow plate (160, 170)