Fuel cell system and method for generating electricity from a fuel cell system comprising a fuel cell stack divided into sub-tracks

• US 7,078,119 B2
• Filed: 06/29/2004
• Issued: 07/18/2006
• Est. Priority Date: 06/29/2004
• Status: Expired due to Fees

• Current Assignee: Nissan Technical Center N.A. Inc.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Takahashi, Shinichi
• Primary Examiner(s): Alejandro, Raymond
• Assistant Examiner(s): Lee, Cynthia
• Application Number:
  US10/878,224
• Publication Number:
  US 20050287406A1
• Time in Patent Office: 749 Days
• Field of Search: 429/24, 429/12, 429 19- 25
• US Class Current: 429/432
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2008/1095 Fuel cells with polymeric electrolytes
• CPC Class Codes: H01M 2250/20 Fuel cells in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04253 Means for solving freezing problems
• CPC Class Codes: H01M 8/04268 Heating of fuel cells during the start-up of the fuel cells
• CPC Class Codes: H01M 8/0432 Temperature; Ambient temperature
• CPC Class Codes: H01M 8/04552 of the individual fuel cell
• CPC Class Codes: H01M 8/04955 Shut-off or shut-down of fuel cells
• CPC Class Codes: H01M 8/249 comprising two or more groupings of fuel cells, e.g. modular assemblies
• 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

Methods of generating electricity from a fuel cell system and fuel cell systems are provided. The fuel cell system comprises a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack. A collector switch connects the current collectors positioned at each end of the fuel cell stack and the current collectors at intermediate positions to a load. The fuel cell system further comprises a means of controlling the collector switch and a means of measuring the temperature of the fuel cell stack. The collector switch is controlled with the means of controlling the collector switch so that the central sub-stack generates electricity before the anode-side sub-stack and the cathode-side sub-stack start to generate electricity. The temperature of the fuel cell stack is measured using the means of measuring the temperature. The collector switch is controlled with the means of controlling the collector switch so that electricity is generated by the anode-side sub-stack, cathode-side sub-stack, and central sub-stack when the means of measuring the temperature of the fuel cell stack measures a temperature greater than or equal to a predetermined temperature. In other embodiments of the invention the means of controlling the collector switch controls the collector switch in response to measurements of the ambient temperature adjacent the fuel cell stack, the voltage across the central sub-stack, or the interval of time from the start of electrical generation of the central sub-stack.

Claims

1. A method of generating electricity from a fuel cell system comprising:

providing a fuel cell system, said fuel cell system comprising a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load, a means of controlling the collector switch, and a means of measuring the temperature of the fuel cell stack;

controlling said collector switch with said means of controlling the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity;

measuring the temperature of said fuel cell stack using said means of measuring the temperature; and

controlling said collector switch with said means of controlling the collector switch so that electricity is generated by the anode-side sub-stack, cathode-side sub-stack, and central sub-stack when said means of measuring the temperature of the fuel cell stack measures a temperature greater than or equal to a predetermined temperature.

2. The method according to claim 1, wherein the predetermined temperature is 0°

C.

3. The method according to claim 1, wherein the means of controlling the collector switch controls the collector switch so that the anode-side and cathode-side sub-stacks immediately start to generate electricity when the means of measuring the temperature of the fuel cell stack measures a temperature greater than or equal to the predetermined temperature.

4. The method according to claim 1, wherein the means of measuring the temperature of the fuel cell stack measures the temperature of the surface or the interior of the central sub-stack and at least one of the surface or interior of either the cathode-side sub-stack or the anode-side sub-stack.

5. The method according to claim 1, wherein the fuel cell system generates electricity by supplying fuel gas and oxidant gas to the fuel cell stack, and heat generated by the fuel cell stack during the generation of electricity is removed by the action of a coolant liquid, wherein the means of measuring the temperature of the fuel cell stack measures the temperature of at least one of the fuel gas, the oxidant gas, or the coolant liquid discharged from the fuel cell stack.

6. A method of generating electricity from a fuel cell system comprising:

providing a fuel cell system, said fuel cell system comprising a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load, a means of controlling the collector switch, and a means of measuring the ambient temperature;

controlling said collector switch with said means of controlling the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity;

measuring the ambient temperature adjacent the fuel cell stack using said means of measuring the ambient temperature; and

controlling said collector switch with said means of controlling the collector switch so that electricity is generated by the anode-side sub-stack, cathode-side sub-stack, and central sub-stack when said means of measuring the ambient temperature measures a temperature greater than or equal to a predetermined temperature.

7. The method according to claim 6, wherein the predetermined temperature is 0°

C.

8. The method according to claim 6, wherein the means of controlling the collector switch controls the collector switch so that the anode-side and cathode-side sub-stacks immediately start to generate electricity when the means of measuring the ambient temperature measures a temperature greater than or equal to the predetermined temperature.

9. A method of generating electricity from a fuel cell system comprising:

providing a fuel cell system, said fuel cell system comprising a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load, a means of controlling the collector switch, and a timer;

controlling said collector switch with said means of controlling the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity;

measuring time from the start of the generation of electricity by the central sub-stack using said timer; and

controlling said collector switch with said means of controlling the collector switch so that electricity is generated by the anode-side sub-stack, cathode-side sub-stack, and central sub-stack when said timer measures a predetermined interval of time.

10. A method of generating electricity from a fuel cell system comprising:

providing a fuel cell system, said fuel cell system comprising a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load, a means of controlling the collector switch, and a means for measuring the voltage of said central sub-stack;

controlling said collector switch with said means of controlling the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity;

measuring the voltage of the central sub-stack using said means of measuring the voltage; and

controlling said collector switch with said means of controlling the collector switch so that electricity is generated by the anode-side sub-stack, cathode-side sub-stack, and central sub-stack when said means of measuring the voltage measures a voltage greater than or equal to a predetermined voltage.

11. A fuel cell system for generating electricity comprising:

a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, wherein each of the anode-side sub-stack, central sub-stack, and cathode-side sub-stack comprises a plurality of unit cells;

a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load;

a means of controlling the collector switch, wherein said means of controlling the collector switch controls the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity; and

a plurality of means of measuring the temperature of said fuel cell stack, wherein one of said plurality of means of measuring the temperature of the fuel cell stack is positioned on or in the interior of said central sub-stack, and another of said plurality of means of measuring the temperature of the fuel cell stack is positioned on or in the interior of either the anode-side or cathode-side sub-stack.

12. The fuel cell system according to claim 11, wherein the anode-side sub-stack and the cathode-side sub-stack each comprise at least three unit cells.

13. The fuel cell system according to claim 11, further comprising a means of controlling the fuel cell stack, wherein the means of controlling the collector switch communicates with the means of controlling the fuel cell stack and the means of controlling the fuel cell stack communicates with the fuel cell stack.

14. A motor vehicle comprising the fuel cell system of claim 11.

15. The motor vehicle according to claim 14, wherein the motor vehicle is an automobile.

18. The fuel cell system according to claim 11, further comprising a means of controlling the fuel cell stack, wherein the means of controlling the collector switch communicates with the means of controlling the fuel cell stack, and the means of controlling the fuel cell stack communicates with the fuel cell stack and the timer.

16. A fuel cell system for generating electricity comprising:

a fuel cell stack divided into an anode-side sub-stack, central sub-stack, and cathode-side sub-stack by current collectors positioned at each end of the fuel cell stack and two current collectors positioned at intermediate positions of the fuel cell stack, wherein each of the anode-side sub-stack, central sub-stack, and cathode-side sub-stack comprises a plurality of unit cells;

a collector switch that connects said current collectors positioned at each end of the fuel cell stack and said current collectors at intermediate positions to a load;

a means of controlling the collector switch, wherein said means of controlling the collector switch controls the collector switch so that said central sub-stack generates electricity before said anode-side sub-stack and said cathode-side sub-stack start to generate electricity; and

a timer for measuring time from the start of the generation of electricity by the central sub-stack, wherein said timer communicates with the means of controlling the collector switch.

17. The fuel cell system according to claim 16, wherein the anode-side sub-stack and the cathode-side sub-stack each comprise at least three unit cells.

19. A motor vehicle comprising the fuel cell system of claim 16.

20. The motor vehicle according to claim 19, wherein the motor vehicle is an automobile.