Sulfur tolerant anode for solid oxide fuel cell

Abstract

A solid oxide fuel cell (SOFC) ( 100 ) for use in generating electricity while tolerating sulfur content in a fuel input stream. The solid oxide fuel cell ( 100 ) includes an electrolyte ( 106 ), a cathode ( 102 ), and a sulfur tolerant anode ( 104 ). The cathode ( 102 ) is disposed on a first side of the electrolyte ( 106 ). The sulfur tolerant anode ( 104 ) is disposed on a second side of the electrolyte ( 106 ) opposite the cathode ( 102 ). The sulfur tolerant anode ( 104 ) includes a composition of nickel, copper, and ceria to exhibit a substantially stable operating voltage at a constant current density in the presence of the sulfur content within the fuel input stream. The solid oxide fuel cell ( 100 ) is useful within a SOFC stack to generate electricity from reformate which includes synthesis gas (syngas) and sulfur content. The solid oxide fuel cell ( 100 ) is also useful within a SOFC stack to generate electricity from unreformed hydrocarbon fuel.

What is claimed is: 
     
         1 . A method for making a solid oxide fuel cell (SOFC), the method comprising:
 disposing a cathode on a first side of an electrolyte; and   disposing a sulfur tolerant anode on a second side of the electrolyte, wherein the sulfur tolerant anode comprises a mixture of nickel (Ni), copper (Cu), and ceria (CeO 2 ) to operate at a substantially stable operating voltage at a constant current density in the presence of a fuel with a measurable sulfur content.   
     
     
         2 . The method of  claim 1 , wherein disposing the sulfur tolerant anode on the second side of the electrolyte comprises:
 mixing nitrates of the nickel, copper, and ceria; and   using a Pechini process to convert the nitrates to mixture of oxides to dispose on the electrolyte.   
     
     
         3 . The method of  claim 2 , further comprising mixing a nitrate of magnesium (Mg) or another electrochemically inert ceramic oxide precursor with the nitrates of the nickel, copper, and ceria. 
     
     
         4 . The method of  claim 2 , further comprising mixing a nitrate of cobalt (Co) or a nitrate of praseodymium (Pr) with the nitrates of the nickel, copper, and ceria. 
     
     
         5 . The method of  claim 2 , further comprising mixing the nitrate of ceria with a. dopant. 
     
     
         6 . The method of  claim 1 , wherein disposing the sulfur tolerant anode on the second side of the electrolyte comprises:
 mixing nitrates of the nickel, copper, and ceria; and   using a glycine nitrate process to convert the nitrates to mixture of oxides to dispose the on the electrolyte.   
     
     
         7 . The method of  claim 1 , wherein disposing the sulfur tolerant anode on the second side of the electrolyte comprises:
 making a mixture of:
 oxides of the nickel, copper, and ceria; 
 an electrochemically inert ceramic oxide; and 
 a catalyst; and 
   using a solid state process to convert the oxides to mixture of oxides to dispose the mixture on the electrolyte.   
     
     
         8 . The method of  claim 1 , wherein disposing the sulfur tolerant anode on the second side of the electrolyte comprises:
 making a mixture of components for the sulfur tolerant anode, wherein the components comprise the nickel, copper, and ceria; and.   infiltrating the mixture into a porous material.   
     
     
         9 . The method of  claim 8 , wherein the mixture comprises nitrates of the nickel, copper, and ceria. 
     
     
         10 . The method of  claim 8 , wherein the mixture comprises fine particles of the nickel, copper, and ceria. 
     
     
         11 . The method of  claim 8 , wherein the porous material comprises an electrolyte material. 
     
     
         12 . The method of  claim 8 , wherein the porous material comprises an inert material disposed on the electrolyte.