System and method to operate a fuel cell in the exhaust of an internal combustion engine

• US 20070190377A1
• Filed: 02/14/2006
• Published: 08/16/2007
• Est. Priority Date: 02/14/2006
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Surnilla, Gopichandra, Bidner, David, Elwart, Shane, Kerns, James
• Granted Patent: US 7,846,595 B2
• Time in Patent Office: Days
• US Class Current: 429/416
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2250/20 Fuel cells in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 8/04373 of auxiliary devices, e.g. reformers, compressors, burners
• CPC Class Codes: H01M 8/04425 at auxiliary devices, e.g. reformers, compressors, burners
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04649 of fuel cell stacks
• CPC Class Codes: H01M 8/04708 of fuel cell reactants
• CPC Class Codes: H01M 8/04798 of fuel cell reactants
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A system for a vehicle having an engine with an exhaust comprises a fuel cell coupled in the engine exhaust wherein the fuel cell has an output circuit; a battery coupled with the fuel cell; and a controller receiving a signal indicative of an electric output of the fuel cell output circuit, and adjusting one of the fuel amount and the air amount supplied to the engine in response to said signal to affect air-fuel ratio of the exhaust of the engine.

Claims

1. A system for a vehicle having an engine with an exhaust, the system comprising:

a fuel cell coupled in the engine exhaust wherein the fuel cell has an output circuit;

a battery coupled with the fuel cell; and

a controller receiving a signal indicative of an electric output of the fuel cell output circuit, and adjusting one of the fuel amount and the air amount supplied to the engine in response to said signal to affect air-fuel ratio of the exhaust of the engine.

2. The system of claim 1, wherein the electric output is one of the current, voltage, and impedance.

3. The system of claim 1, wherein the controller adjusts the fuel and air amounts according to an exhaust ratio which is inferred from the electrical output and exhaust temperature.

4. The system of claim 1, wherein the controller further adjusts an applied current to the fuel cell and said signal is indicative of a change in the current of the fuel cell.

5. The system of claim 1, wherein the electrical output of the fuel cell is used to diagnose degradation of the fuel cell.

6. The system of claim 1, wherein the system further comprises at least one air fuel sensor wherein the electrical output of the fuel cell is used to diagnose degradation of the air fuel sensor.

7. The system of claim 1, wherein the fuel cell is one of a solid oxide fuel cell, molten carbonate fuel cell, and proton exchange membrane fuel cell.

8. The system of claim 1, wherein the system has no air-fuel ratio sensors immediately upstream and no air-fuel ration sensors immediately downstream of the fuel cell.

9. A method to operate an internal combustion engine of a vehicle, the engine also having a fuel cell disposed downstream of the engine coupled in an engine exhaust and a battery coupled with the fuel cell, the method comprising:

adjusting an engine operating parameter in response to an electrical output of the fuel cell coupled in the engine exhaust.

10. The method of claim 9, wherein the electrical output is one of the current, impedance, and voltage, and where said electrical output provides energy to a storage device and said storage device selectively providing energy to an electric motor driving wheels of the vehicle.

11. The method of claim 10, wherein the engine operating parameter is one of the amount of fuel injection, air induction, variable valve timing and exhaust gas recirculation.

12. The method of claim 9 wherein a fuel injection amount in the engine is adjusted in response to the electrical output.

13. The method of claim 12 wherein a closed loop fuel injection of the engine is performed based on the electrical output.

14. The method of claim 13, wherein an exhaust air fuel ratio is inferred from the electrical output.

15. The method of claim 13, wherein an exhaust air fuel ratio is inferred by supplying the current to the fuel cell to generate an electrical output that provides information about exhaust air fuel ratio.

16. The system of claim 9, wherein the fuel cell is one of a solid oxide fuel cell, molten carbonate fuel cell, and proton exchange membrane fuel cell.

17. A method to operate an internal combustion engine of a vehicle, the engine also having a fuel cell disposed at the downstream of the engine and a battery coupled with the fuel cell, the method comprising:

generating an electrical output of the fuel cell by controlling current supplied to the fuel cell from the battery; and

adjusting an engine operating parameter in response to said electrical output of the fuel cell.

18. The method of claim 17, wherein the air fuel ratio of the mixture entering into the fuel cell is inferred from the change of the electrical output of the fuel cell.

19. The method of claim 17, wherein the method further comprises supply current to the fuel cell to reduce NOx discharged from the engine.