Method and apparatus for operating a solid-oxide fuel cell stack with a mixed ionic/electronic conducting electrolyte

Patent metadata

Field	Value
Publication number	US-2017301936-A1
Application number	US-201715640333-A
Country	US
Kind code	A1
Filing date	Jun 30, 2017
Priority date	Feb 10, 2004
Publication date	Oct 19, 2017
Grant date	—

Abstract

A method and apparatus for operating an intermediate-temperature solid-oxide fuel cell stack ( 10 ) with a mixed ionic/electronic conducting electrolyte in order to increase its efficiency. The required power output of the solid-oxide fuel cell stack ( 10 ) is determined and one or more operating conditions of the solid fuel cell stack ( 10 ) are controlled dependent upon the determined required power output. The operating conditions that are controlled may be at least one or the temperature of the fuel cell stack and the dilution of fuel delivered to the fuel cell stack.

First claim

1 - 22 . (canceled)

23 . A method of operating a variable power output solid oxide fuel cell stack comprising at least one solid oxide fuel cell having a mixed ionic/electronic conducting electrolyte, the method comprising the steps of:
(a) determining a present power output and a required power output of said solid oxide fuel cell stack; (b) comparing said determined present power output and required power output of said solid oxide fuel cell stack to determine a required change in the power output of said solid oxide fuel cell stack; and (c) controlling at least one operating condition of said solid oxide fuel cell stack to effect said required change in power output, a required increase in power including an increase in the temperature of said at least one solid oxide fuel cell, and a required decrease in power output including a decrease in the temperature of said solid oxide fuel cell.

24 . A method according to claim 23 , wherein the temperature of the solid oxide fuel cell is maintained at 650° C. or below.

25 . A method according to claim 23 , wherein the temperature of the solid oxide fuel cell is maintained at 600° C. or below.

26 . A method according to claim 23 , said at least one solid oxide fuel cell electrolyte including gadolinium-doped cerium oxide.

27 . A method of operating a variable power output solid oxide fuel cell stack comprising at least one solid oxide fuel cell having a mixed ionic/electronic conducting electrolyte, the method comprising the steps of:
(a) determining a present power output and a required power output of said solid oxide fuel cell stack; (b) comparing said determined present power output and required power output of said solid oxide fuel cell stack to determine a required change in the power output of said solid oxide fuel cell stack; and (c) controlling at least one operating condition of said solid oxide fuel cell stack to effect said required change in power output, a required increase in power output including an increase in the concentration of the fuel delivered to said solid oxide fuel cell, and a required decrease in power output including a decrease in the concentration of fuel delivered to said solid oxide fuel cell.

28 . A method according to claim 27 , wherein fuel delivered to the solid oxide fuel cell is diluted with a predetermined amount of steam, carbon dioxide, nitrogen or a mixture including steam, carbon dioxide and/or nitrogen.

29 . A method according to claim 27 , wherein fuel delivered to the solid oxide fuel cell is diluted with a variable proportion of recycled exhaust gas from an anode side of the at least one fuel cell.

30 . A method according to claim 27 , said at least one solid oxide fuel cell electrolyte including gadolinium-doped cerium oxide.

Assignees

• Ceres Ip Co Ltd

Inventors

• Leah Robert
• Brandon Nigel Peter
• Duckett Athol
• El Koury Karim
• Schmidt Martin

Classifications

• H01M8/04097

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

• H01M8/04731

  of other components of a fuel cell or fuel cell stacks · CPC title

• H01M8/04014 Primary

  Heat exchange using gaseous fluids; Heat exchange by combustion of reactants · CPC title

• H01M8/126

  the electrolyte containing cerium oxide · CPC title

• H01M8/04395

  of cathode reactants at the inlet or inside the fuel cell · CPC title