Method for fabricating a carbon electrode substrate

A method for fabricating an electrochemical cell electrode substrate comprising the steps of:

• coating chopped carbon fibers with a low viscosity mixture of at least 70% furfuryl alcohol, 0.25-5%, by weight, of an aqueous solution of 85% phosphoric acid or an equivalent amount of phosphoric acid, and a balance of water, said step of coating including dispersing said fibers in a bath of said mixture;
• forming a mat of said coated fibers, including permitting said dispersed fibers to settle onto a screen disposed in said bath;
• polymerizing the furfuryl alcohol and curing the mat by heating the mat to a temperature between 50.degree.-200.degree. C. in an oxidizing atmosphere;
• and
• carbonizing the cured mat by heating to at least 1500.degree. C.

A method for fabricating a fuel cell electrode substrate comprising the steps of:

• coating chopped carbon pitch fibers which are less than about two inches in length with a mixture of at least 85% furfuryl alcohol, 0.25-5%, by weight, of an aqueous solution of 85% phosphoric acid or an equivalent amount of phosphoric acid, and a balance of water, said step of coating including dispersing said fibers in a bath of said mixture;
• forming a mat of said coated fibers, including permitting said dispersed fibers to settle onto a screen disposed in said bath;
• polymerizing the furfuryl alcohol and fully curing the mat by heating the mat to a temperature between 100.degree.-150.degree. C. in an oxidizing atmosphere;
• and
• carbonizing the cured mat by heating to at least 1900.degree. C.