Method and apparatus for a fuel cell based fuel sensor

• US 6,500,574 B2
• Filed: 12/15/2000
• Issued: 12/31/2002
• Est. Priority Date: 12/15/2000
• Status: Expired due to Fees

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Keegan, Kevin R.
• Primary Examiner(s): Kalafut, Stephen
• Assistant Examiner(s): ALEJANDRO, RAYMOND
• Application Number:
  US09/738,207
• Publication Number:
  US 20020076590A1
• Time in Patent Office: 746 Days
• Field of Search: 429/23, 429/22, 429/13, 429/12, 429/30, 429/33, 204/421, 204/422, 204/424, 204/431, 204/196.02, 204/228.01, 204/229.8, 204/555, 204/556
• US Class Current: 429/432
• CPC Class Codes: G01N 27/4074 for detection of gases other than oxygen
• CPC Class Codes: H01M 2300/0074 Ion conductive at high temperature
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

Fuel concentrations are determinable in a solid oxide fuel cell through voltage measurement of one or more fuel cell units, which voltage is a function of hydrogen gas present in the fuel feed stream to the one or more fuel cell units. The voltage in the one or more fuel cell units is proportionally related to the fuel concentration in the fuel feed stream to the entire fuel cell. A sensor determines concentrations of the fuel flowing in the fuel cell. The sensor comprises a fuel cell unit, and an indicator electrically coupled to the fuel cell unit, the indicator being capable of displaying a voltage or being adapted to convert a voltage to a fuel concentration display. The voltage measured is correlated to the fuel concentration flowing in the fuel cell.

Claims

1. A method of sensing a fuel concentration of a fuel cell comprising:

measuring a voltage of said fuel cell, wherein said fuel cell is a solid oxide fuel cell; and

determining said fuel concentration flowing through said fuel cell based on said voltage.

2. The method of sensing a fuel concentration of a fuel cell as in claim 1 wherein said determining comprises:

correlating said voltage to said fuel concentration.

3. The method of sensing a fuel concentration of a fuel cell as in claim 2 wherein said measuring is done with at least a portion of at least one sensor, said at least one sensor includes;

a cathode;

an anode spaced from said cathode; and

an electrolyte disposed between said cathode and said anode; and

an indicator electrically coupled to both said anode and said cathode.

4. The method of sensing a fuel concentration of a fuel cell as in claim 3 wherein said indicator determines said voltage of said at least one sensor.

5. The method of sensing a fuel concentration of a fuel cell as in claim 2 wherein said fuel cell has a plurality of fuel cell units, each of said plurality of fuel cell units include;

a cathode;

an anode spaced from said cathode; and

an electrolyte disposed between said cathode and said anode;

a fuel flow contacting said anode;

an oxidant flow contacting said cathode;

an electron flow of said fuel cell unit coupled from said anode to an electrical load and said electrical load coupled to said cathode wherein said electron flow of said plurality of fuel cell units flows through said anode, to said electrical load, to said cathode.

6. The method of sensing a fuel concentration of a fuel cell as in claim 3 wherein said at least one sensor in said fuel cell is electrically isolated from an electron flow of said fuel cell.

7. The method of sensing a fuel concentration of a fuel cell as in claim 5 wherein said fuel flow is hydrogen;

and said oxidant flow is air.

8. The method of sensing a fuel concentration of a fuel cell as in claim 5 wherein said correlating said voltage to said fuel concentration comprises varying said electrical load, measuring said voltage at said sensor, and relating said voltage to said fuel concentration with respect to said varying electrical load.