Method for forming a solid oxide fuel cell

Abstract

A method for forming a solid oxide fuel cell of yttria stabilized zirconia on a substrate, separating the resultant electrolytic layer from the substrate, and thereafter plasma spraying ceramic powder materials and forming an anode and a cathode on the electrolytic layer.

I claim: 
     
       1. A method for forming a solid oxide fuel cell, comprising: step 1--preparing a substrate of corrugated configuration to have a surface roughness in the range of about 30 to about 70 μ inches (0.00030-0.00070 inches);   step 2--plasma spraying a first ceramic powder material comprising yttria stabilized zirconia (Y-ZrO 2 ) onto said substrate;   step 3--continuing to plasma spray said first material onto said substrate and forming an electrolytic layer of said first material having first and second surfaces and a thickness in the range of about 0.02 inches to about 0.05 inches;   step 4--separating the electrolytic layer from said substrate;   step 5--plasma spraying a second ceramic powder material on the first surface of the electrolytic layer and plasma spraying a third ceramic powder material on the second surface of the electrolytic layer prior to heating of the electrolytic layer after separation step #4, wherein said second material is an anode material or a cathode material and said third material being the other of said anode material and cathode material;   step 6--continuing to plasma spray said anode material and forming an anode layer on said electrolytic layer, said anode layer having a thickness in the range of about 0.002 to about 0.01 inches and continuing to spray said cathode material and forming a cathode layer on the electrolytic layer having a thickness in the range of about 0.002 to about 0.01 inches, said anode material being nickel zirconia composite (Ni/ZrO 2 ) and said cathode material being strontium doped lanthanum manganate (Sr-LaMnO 3 ) and thereby forming a 3-layer composite;   step 7--repeating steps 2-6 and forming a second 3-layer composite;   step 8--plasma spraying an interconnect material of magnesium doped chromate (LaMgCrO 3 ), densified with magnesia-chromic oxide (Mgo-Cr 2  O 3 ), on at least one of the 3-layer composites;   step 9--assembling the 3-layer composites together; and   step 10--bonding the assembled 3-layer composites together to form a unit and increasing and density of the unit to a value greater than 95% theoretical density by firing the unit to a temperature sufficient.