Catalytic bipolar interconnection plate for use in a fuel cell

A bipolar interconnection plate for placement between individual fuel cell units in a stacked, multiple fuel cell power generation system, each fuel cell unit comprising an anode member, a cathode member, and a portion of electrolyte material positioned between said anode member and said cathode member, said bipolar interconnection plate comprising a first side and a second side, said first side comprising a plurality of elongate gas flow channels therein, all of said gas flow channels in said first side of said plate being parallel to each other and extending longitudinally along said plate in a first direction, said second side comprising a plurality of elongate fuel flow channels therein, all of said fuel flow channels in said second side of said plate being parallel to each other and extending longitudinally along said plate in a second direction, said second direction being perpendicular to said first direction, said plate being comprised of about 40-80% by weight of a catalytic intermetallic compound capable of catalyzing steam reforming of hydrocarbon fuel compositions into hydrogen, carbon monoxide, and carbon dioxide during operation of said fuel cell power generation system, said intermetallic compound being selected from the group consisting of Ni.sub.3 Al and NiAl, said plate further comprising about 20-60% by weight of a ceramic filler composition randomly dispersed therein in order to form a porous plate structure having a lower coefficient of thermal expansion compared with plate structures comprised of said intermetallic compound which lack said ceramic filler composition, said ceramic filler composition being selected from the group consisting of zirconia, zirconium silicate, mullite, alumina, calcium zirconium phosphate, strontium zirconium phosphate, and cordierite, said first side of said interconnection plate comprising an electrically conductive protective coating thereon, said protective coating being selected from the group consisting of strontium-doped lanthanum chromite, calcium-doped lanthanum chromite, strontium-doped lanthanum cobaltite, calcium-doped lanthanum cobaltite, strontium-doped gadolinium cobaltite, calcium-doped gadolinium cobaltite, strontium-doped yttrium chromite, calcium-doped yttrium chromite, strontium-doped neodymium chromite, calcium-doped neodymium chromite, strontium-doped yttrium ferrite, and calcium-doped yttrium ferrite.

A stacked, multiple fuel cell power generation system comprising:

• a plurality of individual fuel cell units, each fuel cell unit comprising an anode member, a cathode member, and a portion of electrolyte material positioned between said anode member and said cathode member;
• and
• a plurality of bipolar interconnection plates, one of said plates being positioned between each of said fuel cell units in said power generation system in order to separate said fuel cell units from each other, each of said bipolar interconnection plates comprising a first side and a second side, said first side comprising a plurality of elongate gas flow channels therein, and said second side comprising a plurality of elongate fuel flow channels therein, each of said plates being comprised of a catalytic intermetallic compound capable of catalyzing steam reforming of hydrocarbon fuel compositions into hydrogen, carbon monoxide, and carbon dioxide during operation of said fuel cell power generation system, said intermetallic compound being selected from the group consisting of NiAl and Ni.sub.3 Al, each of said plates further comprising at least one ceramic filler composition randomly dispersed therein in order to form a porous plate structure having a lower coefficient of thermal expansion compared with plate structures comprised of said intermetallic compound which lack said ceramic filler composition.

A stacked, multiple-fuel cell power generation system comprising:

• a plurality of individual fuel cell units, each fuel cell unit comprising an anode member, a cathode member, and a portion of electrolyte material positioned between said anode member and said cathode member;
• and
• a plurality of bipolar interconnection plates, one of said plates being positioned between each of said fuel cell units in said power generation system in order to separate said fuel cell units from each other, each of said plates comprising a first side and a second side, said first side comprising a plurality of elongate gas flow channels therein, and said second side comprising a plurality of elongate fuel flow channels therein, each of said plates being comprised of a catalytic intermetallic compound capable of catalyzing steam reforming of hydrocarbon fuel compositions into hydrogen, carbon monoxide, and carbon dioxide during operation of said fuel cell power generation system, said intermetallic compound being selected from the group consisting of NiAl and Ni.sub.3 Al, each of said plates further comprising at least one ceramic filler composition randomly dispersed therein in order to form a porous plate structure having a lower coefficient of thermal expansion compared with plate structures comprised of said intermetallic compound which lack said ceramic filler composition, said first side of each of said interconnection plates comprising an electrically conductive protective coating thereon.

A stacked, multiple fuel cell power generation system comprising:

• a plurality of individual fuel cell units, each fuel cell unit comprising an anode member, said anode member being comprised of elemental Ni and zirconia, a cathode member comprised of lanthanum manganite, and a portion of electrolyte material comprised of zirconia positioned between said anode member and said cathode member;
• and
• a plurality of bipolar interconnection plates, one of said plates being positioned between each of said fuel cell units in said power generation system in order to separate said fuel cell units from each other, each of said plates comprising a first side and a second side, said first side comprising a plurality of elongate gas flow channels therein, all of said gas flow channels being parallel to each other and extending longitudinally in a first direction, said second side comprising a plurality of elongate fuel flow channels therein, all of said fuel flow channels being parallel to each other and extending longitudinally in a second direction, said second direction being perpendicular to said first direction, each of said plates being comprised of about 40-80% by weight of a catalytic intermetallic compound capable of catalyzing steam reforming of hydrocarbon fuel compositions into hydrogen, carbon monoxide, and carbon dioxide during operation of said fuel cell power generation system, said intermetallic compound being selected from the group consisting of NiAl and Ni.sub.3 Al, each of said plates further comprising about 20-60% by weight of a ceramic filler composition randomly dispersed therein in order to form a porous plate structure having a lower coefficient of thermal expansion compared with plate structures comprised of said intermetallic compound which lack said ceramic filler composition, said ceramic filler composition being selected from the group consisting of zirconia, zirconium silicate, mullite, alumina, calcium zirconium phosphate, strontium zirconium phosphate, and cordierite, said first side of each of said interconnection plates comprising an electrically conductive protective coating thereon, said protective coating being selected from the group consisting of strontium-doped lanthanum chromite, calcium-doped lanthanum chromite, strontium-doped lanthanum cobaltite, calcium-doped lanthanum cobaltite, strontium-doped gadolinium cobaltite, calcium-doped gadolinium cobaltite, strontium-doped yttrium chromite, calcium-doped yttrium chromite, strontium-doped neodymium chromite, calcium-doped neodymium chromite, strontium-doped yttrium ferrite, and calcium-doped yttrium ferrite, at least one of said bipolar interconnection plates in said fuel cell power generation system being attached to said anode member of one of said fuel cell units by a metallic brazing alloy secured therebetween, said metallic brazing alloy having a melting point greater than about 1200.degree. C.

A method for producing a bipolar interconnection plate for use in a fuel cell power generation system comprising the steps of:

• combining elemental Al powder, elemental Ni powder, and at least one ceramic filler powder in order to form a mixture, said elemental Al powder and said elemental Ni powder being present in said mixture in an Al:Ni molar ratio of about 1:1;
• compressing said mixture to form a compressed product;
• and
• heating said compressed product to a temperature of about 600.degree.-1000.degree. C. in order to cause said compressed product to solidify and produce said bipolar interconnection plate, said heating causing said elemental Al powder and said elemental Ni powder to form a metallic matrix within said plate comprised of intermetallic NiAl having said ceramic filler powder randomly dispersed therein.

A method for producing a bipolar interconnection plate for use in a fuel cell power generation system comprising the steps of:

• combining elemental Al powder, elemental Ni powder, and at least one ceramic filler powder in order to form a mixture, said elemental Al powder and said elemental Ni powder being present in said mixture in an Al:Ni molar ratio of about 1:1;
• compressing said mixture to form a compressed product;
• heating said compressed product to a temperature of about 600.degree.-1000.degree. C. in order to cause said compressed product to solidify and produce said bipolar interconnection plate, said heating causing said elemental Al powder and said elemental Ni powder to form a metallic matrix within said plate comprised of intermetallic NiAl having said ceramic filler powder randomly dispersed therein;
• and
• applying an electrically conductive protective coating to at least a portion of said bipolar interconnection plate, said protective coating being applied to said portion of said plate by liquid injection plasma deposition.

A method for producing a bipolar interconnection plate for use in a fuel cell power generation system comprising the steps of:

• combining elemental Al powder, elemental Ni powder, and at least one ceramic filler powder in order to form a mixture, said elemental Al powder and said elemental Ni powder being present in said mixture in an Al:Ni molar ratio of about 1:3;
• compressing said mixture to form a compressed product;
• and
• heating said compressed product to a temperature of about 600.degree.-1000.degree. C. in order to cause said compressed product to solidify and produce said bipolar interconnection plate, said heating causing said elemental Al powder and said elemental Ni powder to form a metallic matrix within said plate comprised of intermetallic Ni.sub.3 Al having said ceramic filler powder randomly dispersed therein.

A method for producing a bipolar interconnection plate for use in a fuel cell power generation system comprising the steps of:

• combining elemental Al powder, elemental Ni powder, and at least one ceramic filler powder in order to form a mixture, said elemental Al powder and said elemental Ni powder being present in said mixture in an Al:Ni molar ratio of about 1:3;
• compressing said mixture to form a compressed product;
• heating said compressed product to a temperature of about 600.degree.-1000.degree. C. in order to cause said compressed product to solidify and produce said bipolar interconnection plate, said heating causing said elemental Al powder and said elemental Ni powder to form a metallic matrix within said plate comprised of intermetallic Ni.sub.3 Al having said ceramic filler powder randomly dispersed therein;
• and
• applying an electrically conductive protective coating to at least a portion of said bipolar interconnection plate, said protective coating being applied to said portion of said plate by liquid injection plasma deposition.