Solid oxide fuel cell system and a method of operating a solid oxide fuel cell system

Patent metadata

Field	Value
Publication number	US-9972855-B2
Application number	US-201113991085-A
Country	US
Kind code	B2
Filing date	Nov 10, 2011
Priority date	Dec 1, 2010
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A solid oxide fuel cell system ( 10 ) comprises a solid oxide fuel cell stack ( 12 ) and an electrochemical device ( 14 ). The solid oxide fuel cell stack ( 12 ) comprises at least one solid oxide fuel cell ( 16 ) and each solid oxide fuel cell ( 16 ) comprises an electrolyte ( 18 ), an anode ( 20 ) and a cathode ( 22 ). An oxidant supply ( 24 ) is arranged to supply oxidant to the cathode ( 22 ) of the at least one solid oxide fuel cell ( 16 ) and a fuel supply ( 26 ) is arranged to supply fuel to the anode ( 20 ) of the at least one solid oxide fuel cell ( 16 ). The electrochemical device ( 14 ) comprises an electrolyte ( 34 ), an anode ( 36 ) and a cathode ( 38 ). Means ( 28, 50, 52 ) to supply a portion of the unused fuel from the anode ( 20 ) of the at least one solid oxide fuel cell ( 16 ) to the anode ( 36 ) of the electrochemical device ( 14 ), means ( 32, 50, 58 ) to supply a portion of the unused fuel from the anode ( 20 ) of the at least one solid oxide fuel cell ( 16 ) to the cathode ( 38 ) of the electrochemical device ( 14 ). In use the electrochemical device ( 14 ) is arranged to remove oxygen from the unused fuel at the cathode ( 38 ) of the electrochemical device ( 14 ) and the electrochemical device ( 14 ) is arranged to transfer oxygen through the electrolyte ( 34 ) from the unused fuel at the cathode ( 38 ) of the electrochemical device ( 14 ) to the unused fuel at the anode ( 36 ) of the electrochemical device ( 14 ). The electrochemical device ( 14 ) is arranged to oxidise the unused fuel at the anode ( 34 ) of the electrochemical device ( 14 ) and means ( 32, 60, 62, 68 ) to supply the portion of oxygen depleted unused fuel from the cathode ( 38 ) of the electrochemical device ( 14 ) to the anode ( 20 ) of the at least one solid oxide fuel cell ( 16 ).

First claim

The invention claimed is:

1. A solid oxide fuel cell system comprising:
a solid oxide fuel cell stack, the solid oxide fuel cell stack comprising at least one solid oxide fuel cell, each solid oxide fuel cell comprising an electrolyte, an anode and a cathode, an oxidant supply being arranged to supply oxidant to the cathode of the at least one solid oxide fuel cell, a fuel supply being arranged to supply fuel to the anode of the at least one solid oxide fuel cell,
an electrochemical device, the electrochemical device comprising an electrolyte, an anode and a cathode,
a duct to supply a portion of unused fuel from the anode of the at least one solid oxide fuel cell to the cathode of the electrochemical device,
a duct to supply a portion of the unused fuel from the anode of the at least one solid oxide fuel cell to the anode of the electrochemical device,
wherein the electrochemical device is arranged to remove oxygen from the unused fuel at the cathode of the electrochemical device substantially throughout an operating cycle of the solid oxide fuel cell system by generating, when the electrochemical device is supplied with electricity, oxygen ions from the oxygen from the unused fuel at the cathode and transporting the generated oxygen ions across the electrolyte to the anode such that the transported oxygen ions are available to the unused fuel at the anode,
a duct to supply the portion of oxygen depleted unused fuel from the cathode of the electrochemical device to the anode of the at least one solid oxide fuel cell, and
a duct to supply the portion of the unused fuel and oxygen at the anode of the electrochemical device to a combustor.

2. The solid oxide fuel cell system of claim 1 , further comprising a duct to supply a portion of the unused fuel from the anode of the at least one solid oxide fuel cell directly to the combustor.

3. The solid oxide fuel cell system of claim 1 , further comprising a gas turbine engine, the gas turbine engine comprising a compressor and a turbine arranged to drive the compressor, the compressor being arranged to supply at least a portion of the oxidant to the cathode of the at least one solid oxide fuel cell.

4. The solid oxide fuel cell system of claim 1 , further comprising a duct to supply a portion of unused oxidant from the cathode of the at least one solid oxide fuel cell back to the cathode of the at least one solid oxide fuel cell.

5. The solid oxide fuel cell system of claim 4 , further comprising a duct to supply a portion of the unused oxidant from the cathode of the at least one solid oxide fuel cell to the combustor.

6. The solid oxide fuel cell system of claim 4 , further comprising a duct to supply exhaust gases from the combustor to the turbine of the gas turbine engine.

7. The solid oxide fuel cell system of claim 6 , wherein the duct to supply the exhaust gases from the combustor to the turbine of the gas turbine engine comprises a heat exchanger.

8. The solid oxide fuel cell system of claim 4 , wherein the duct to supply a portion of the unused oxidant from the cathode of the at least one solid oxide fuel cell back to the cathode of the at least one solid oxide fuel cell comprises a heat exchanger.

9. The solid oxide fuel cell system of claim 1 , wherein the solid oxide fuel cell stack is arranged to supply electricity to the electrochemical device.

10. The solid oxide fuel cell system of claim 1 , wherein the turbine of the gas turbine engine is arranged to drive an electrical generator.

11. The solid oxide fuel cell system of claim 10 , wherein the electrical generator is arranged to supply electricity to the electrochemical device.

12. A solid oxide fuel cell system comprising:
a solid oxide fuel cell stack, the solid oxide fuel cell stack comprising at least one solid oxide fuel cell, each solid oxide fuel cell comprising an electrolyte, an anode and a cathode, an oxidant supply being arranged to supply oxidant to the cathode of the at least one solid oxide fuel cell, a fuel supply being arranged to supply fuel to the anode of the at least one solid oxide fuel cell,
an electrochemical device, the electrochemical device comprising an electrolyte, an anode and a cathode,
a duct to supply a portion of unused fuel from the anode of the at least one solid oxide fuel cell to the cathode of the electrochemical device,
a duct to supply a portion of the unused fuel from the anode of the at least one solid oxide fuel cell to the anode of the electrochemical device,
wherein the electrochemical device, when supplied with electricity, is arranged to remove oxygen from the unused fuel at the cathode of the electrochemical device substantially throughout an operating cycle of the solid oxide fuel cell system by transferring the oxygen through the electrolyte from the unused fuel at the cathode of the electrochemical device to the unused fuel at the anode of the electrochemical device,
a duct supply the portion of oxygen depleted unused fuel from the cathode of the electrochemical device to the anode of the at least one solid oxide fuel cell, and
a duct to supply the portion of the unused fuel and oxygen at the anode of the electrochemical device to a combustor.

Assignees

• Bozzolo Michele
• Agnew Gerald Daniel
• Lg Fuel Cell Systems Inc

Inventors

• Bozzolo Michele
• Agnew Gerald Daniel

Classifications

• H01M8/04201 Primary

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title

• H01M8/04022 Primary

  Heating by combustion · CPC title

• H01M8/0681 Primary

  Reactant purification by the use of electrochemical cells · CPC title

• H01M8/04097

  with recycling of the reactants (H01M8/04119, H01M8/04104 take precedence) · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title