Switching modes of operation of a fuel cell

• US 7,521,146 B2
• Filed: 12/27/2005
• Issued: 04/21/2009
• Est. Priority Date: 12/27/2005
• Status: Expired due to Fees

• Current Assignee: Plug Power Inc.
• Original Assignee: Plug Power Inc.
• Inventors: Lang, Timothy, Pomykai, Michael, Mason, Richard W.
• Primary Examiner(s): Ryan; Patrick
• Assistant Examiner(s): Wang; Eugenia
• Application Number:
  US11/319,044
• Publication Number:
  US 20070148507A1
• Time in Patent Office: 1,211 Days
• Field of Search: 429/34, 429/39, 205/637
• US Class Current: 429/439
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: H01M 8/04365 of other components of a fuel cell or fuel cell stacks
• CPC Class Codes: H01M 8/04552 of the individual fuel cell
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04671 of the individual fuel cell
• CPC Class Codes: H01M 8/04731 of other components of a fuel cell or fuel cell stacks
• CPC Class Codes: H01M 8/04753 of fuel cell reactants
• CPC Class Codes: H01M 8/04761 of fuel cell exhausts
• CPC Class Codes: H01M 8/04955 Shut-off or shut-down of fuel cells
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A technique that is usable with a fuel cell stack includes routing an anode exhaust of the fuel cell stack to an anode exhaust line. Based on a mode operation of the fuel cell stack, communication is selectively established between a cathode chamber of the fuel cell stack and the anode exhaust line.

Claims

1. A method usable with a fuel cell stack, comprising:

routing an anode exhaust of the fuel cell stack to an anode exhaust line;

isolating the anode exhaust from a cathode chamber of the fuel cell stack; and

while maintaining the isolation of the anode exhaust from the cathode chamber, selectively establishing communication between the cathode chamber of the fuel cell stack and the anode exhaust line based on a mode of operation of the fuel cell stack,

wherein the act of selectively establishing communication comprises;

connecting a cathode inlet of the fuel cell stack to the anode exhaust line in response to the fuel cell stack being configured to operate as an electrochemical pump.

2. The method of claim 1, further comprising:

selectively connecting a power supply to the fuel cell stack based on the mode of operation of the fuel cell stack.

3. The method of claim 1, further comprising:

selectively regulating a load connected to the fuel cell stack based on the mode of operation of the fuel cell stack.

4. A method usable with a fuel cell stack, comprising:

routing an anode exhaust of the fuel cell stack to an anode exhaust line;

isolating the anode exhaust from a cathode chamber of the fuel cell stack; and

while maintaining the isolation of the anode exhaust from the cathode chamber, selectively establishing communication between the cathode chamber of the fuel cell stack and the anode exhaust line based on a mode of operation of the fuel cell stack,

wherein the act of selectively establishing communication comprises;

controlling a valve to isolate a cathode inlet of the fuel cell stack from the anode exhaust line in response to the fuel cell stack being configured to not operate as an electrochemical pump.

5. The method of claim 4, further comprising:

selectively connecting a power supply to the fuel cell stack based on the mode of operation of the fuel cell stack.

6. The method of claim 4, further comprising:

selectively regulating a load connected to the fuel cell stack based on the mode of operation of the fuel cell stack.

7. A method usable with a fuel cell stack, comprising:

routing an anode exhaust of the fuel cell stack to an anode exhaust line;

isolating the anode exhaust from a cathode chamber of the fuel cell stack; and

while maintaining the isolation of the anode exhaust from the cathode chamber, selectively establishing communication between the cathode chamber of the fuel cell stack and the anode exhaust line based on a mode of operation of the fuel cell stack,

wherein the act of selectively establishing communication comprises;

connecting a cathode outlet of the fuel cell stack to the anode exhaust line in response to the fuel cell stack being configured to operate as an electrochemical pump.

8. The method of claim 7, further comprising:

selectively connecting a power supply to the fuel cell stack based on the mode of operation of the fuel cell stack.

9. The method of claim 7, further comprising:

selectively regulating a load connected to the fuel cell stack based on the mode of operation of the fuel cell stack.

10. A method usable wit a fuel cell stack, comprising:

routing an anode exhaust of the fuel cell stack to an anode exhaust line;

isolating the anode exhaust from a cathode chamber of the fuel cell stack; and

while maintaining the isolation of the anode exhaust from the cathode chamber, selectively establishing communication between the cathode chamber of the fuel cell stack and the anode exhaust line based on a mode of operation of the fuel cell stack,

wherein the act of selectively establishing communication comprises;

controlling a valve to isolate a cathode outlet of the fuel cell stack from the anode exhaust line in response to the fuel cell stack being configured to not operate as an electrochemical pump.

11. The method of claim 10, farther comprising:

selectively connecting a power supply to the fuel cell stack based on the mode of operation of the fuel cell stack.

12. The method of claim 10, further comprising:

selectively regulating a load connected to the fuel cell stack based an the mode of operation of the fuel cell stack.