Solid oxide fuel cells fueled with reducible oxides

Patent metadata

Field	Value
Publication number	US-9865894-B2
Application number	US-201514843385-A
Country	US
Kind code	B2
Filing date	Sep 2, 2015
Priority date	Sep 2, 2014
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

A direct-electrochemical-oxidation fuel cell for generating electrical energy includes a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode, a solid-state reduced metal, a solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of the solid-state reduced metal in the presence of the oxygen ions to produce electrical energy, and an electrolyte disposed to transmit the oxygen ions from the cathode to the solid-state anode. A method of operating a solid oxide fuel cell includes providing a direct-electrochemical-oxidation fuel cell comprising a solid-state reduced metal, oxidizing the solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide, and reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.

First claim

What is claimed is:

1. A direct-electrochemical-oxidation fuel cell for generating electrical energy comprising:
a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode;
a solid-state electrolyte disposed to transmit the oxygen ions from the cathode to a solid-state anode;
the solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of a solid-state reduced metal in the presence of the oxygen ions to produce electrical energy and a solid-state reducible metal oxide; and
an external reducer for converting said solid-state reducible metal oxide back to the solid-state reduced metal.

2. The fuel cell of claim 1 , wherein electricity is generated by direct electrochemical oxidation at the solid-state anode according to the reaction:
M+XO 2− →MO X +2Xe −

where M is the solid-state reduced metal and is a transition metal, where MO x is a solid-state reducible metal oxide, and where X is a number from 0.1 to 3.

3. The fuel cell of claim 2 , wherein M is a metal selected from the group consisting of Fe, Cu, Co, Ni, Ag, Au, and alloys thereof.

4. The fuel cell of claim 3 , wherein M is Fe.

5. The fuel cell of claim 2 , wherein X is a number from 1 to 3.

6. The fuel cell of claim 1 , wherein said solid-state reduced metal is distributed in a reduced pellet having low resistivity.

7. The fuel cell of claim 1 , wherein said cathode comprises a cathode interlayer and a cathode current collector layer, and wherein said solid-state anode comprises an anode interlayer and an anode support layer.

8. The fuel cell of claim 1 , wherein said solid-state anode comprises an additional impregnation of a catalyst component, the additional impregnation being selected from the group consisting of Ba, Sc, Th, Y, Ce, Gd, Sm, La, Sr, Co, and Fe ions, and combinations thereof.

9. A method of operating the direct-electrochemical-oxidation fuel cell of claim 1 comprising the steps of:
oxidizing the solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide and
reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.

10. The method of claim 9 , further comprising the steps of allowing the cathode provided with the electrochemical-reduction catalyst to form oxygen ions from the oxygen-containing source at the cathode and allowing the electrolyte to transmit the oxygen ions from the cathode to the solid-state anode, wherein the step of oxidizing is achieved by the solid-state anode provided with the electrochemical-oxidation catalyst and results in the production of electrical energy.

11. The method of claim 9 , further comprising the step of supplying the solid-state reducible metal oxide to the external reducer, wherein the step of reducing occurs in the external reducer.

12. The method of claim 11 , further comprising the step of providing the solid-state reduced metal to the direct-electrochemical-oxidation fuel cell after said step of reducing.

13. The method of claim 11 , wherein said step of reducing occurs in the presence of a carbonaceous fuel.

14. The method of claim 9 , wherein said step of reducing occurs by supplying hydrogen to the solid-state reducible metal oxide.

15. The method of claim 9 , wherein said step of reducing occurs by supplying electrical energy to the direct-electrochemical-oxidation fuel cell.

16. The method of claim 10 , wherein the rate of direct-electrochemical-oxidation of the solid state reduced metal is accelerated by providing an additional catalyst on the surface of the anode.

17. The method of claim 10 , wherein the rate of direct-electrochemical-oxidation of the solid state reduced metal is accelerated by incorporating a catalyst with the solid state reduced metal.

Assignees

• Chuang Steven S
• Fan Liang Shih
• Univ Akron
• Univ Ohio State

Inventors

• Chuang Steven S
• Fan Liang Shih

Classifications

• H01M4/9066

  of metal-ceramic composites or mixtures, e.g. cermets · CPC title

• H01M8/184

  Regeneration by electrochemical means · CPC title

• H01M4/8889

  Cosintering or cofiring of a catalytic active layer with another type of layer · CPC title

• Y02E60/525

  Cross-Sectional Technologies · mapped topic

• Y02P70/56

  Cross-Sectional Technologies · mapped topic