Method of making an electrochemical cell electrode

Claim 1

A method for manufacturing an electrochemical cell electrode comprising: (1) preparing an aqueous floc of a catalyst; (2) applying said aqueous floc onto a substrate in an amount which is a fraction of the total amount required; (3) filtering the aqueous portion of the floc through the substrate, thereby producing a catalyst rich layer; (4) compacting the catalyst layer disposed on the substrate to form an essentially smooth surface; (5) serially repeating said applying, filtering and compacting steps until the total amount of catalyst is deposited, thereby serially depositing a number of thin, fractional, uniformly compacted and densified catalyst layers to the substrate, which together provide the total amount of catalyst required; (6) drying the catalyst bearing substrate; and, (7) sintering the catalyst bearing substrate, thereby forming an electrode.

Claim 2

A method for manufacturing an electrochemical cell electrode comprising: (1) preparing an aqueous floc of a catalyst; (2) applying said aqueous floc onto a substrate in an amount which is a fraction of the total amount required; (3) filtering the aqueous portion of the floc through the substrate, thereby producing a catalyst rich layer; (4) compacting the catalyst layer disposed on the substrate to form an essentially smooth surface; (5) serially repeating said applying, filtering and compacting steps until the total amount of catalyst is deposited, thereby serially depositing a number of thin, fractional, uniformly compacted and densified catalyst layers to the substrate, which together provide the total amount of catalyst required; (6) drying the catalyst bearing substrate; and, (7) sintering the catalyst bearing substrate, thereby forming an electrode.

Claim 7

A method for manufacturing an essentially crack-free electrochemical cell electrode including the steps of applying an aqueous catalyst floc to a substrate, filtering the aqueous liquid portion of the floc through the substrate, compacting the deposited catalyst, drying and sintering, wherein the improvement comprises: (1) applying said aqueous floc in an amount which is a fraction of the total amount required; (2) dewatering the applied floc, thereby forming a thin solids rich layer which is a fraction of the total desired catalyst amount; (3) compacting the catalyst layer disposed on the substrate; and (4) serially repeating said applying, dewatering and compacting steps until the total catalyst amount is deposited, thereby serially depositing a number of thin fractional uniformly compacted and densified catalyst layers to the substrate.

Claim 8

A method for manufacturing an essentially crack-free electrochemical cell electrode including the steps of applying an aqueous catalyst floc to a substrate, filtering the aqueous liquid portion of the floc through the substrate, compacting the deposited catalyst, drying and sintering, wherein the improvement comprises: (1) applying said aqueous floc in an amount which is a fraction of the total amount required; (2) dewatering the applied floc, thereby forming a thin solids rich layer which is a fraction of the total desired catalyst amount; (3) compacting the catalyst layer disposed on the substrate; and (4) serially repeating said applying, dewatering and compacting steps until the total catalyst amount is deposited, thereby serially depositing a number of thin fractional uniformly compacted and densified catalyst layers to the substrate.