Fuel cell system

• US 20030148154A1
• Filed: 01/09/2003
• Published: 08/07/2003
• Est. Priority Date: 05/23/2001
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Kawasumi, Emi, Ichikawa, Hiroyuki, Iwasaki, Yasukazu
• Granted Patent: US 7,147,946 B2
• Time in Patent Office: Days
• US Class Current: 429/20
• CPC Class Codes: B60L 58/31 for starting of fuel cells
• CPC Class Codes: B60L 58/34 by heating
• CPC Class Codes: C01B 2203/0227 containing a catalytic reforming step
• CPC Class Codes: C01B 2203/0244 the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• CPC Class Codes: C01B 2203/044 Selective oxidation of carbon monoxide
• CPC Class Codes: C01B 2203/047 the impurity being carbon monoxide
• CPC Class Codes: C01B 2203/0844 the non-combustive exothermic reaction being another reforming reaction as defined in groups C01B2203/02 - C01B2203/0294
• CPC Class Codes: C01B 2203/142 At least two reforming, decomposition or partial oxidation steps in series
• CPC Class Codes: C01B 2203/1604 Starting up the process
• CPC Class Codes: C01B 2203/1619 Measuring the temperature
• CPC Class Codes: C01B 2203/169 Controlling the feed
• CPC Class Codes: C01B 2203/82 Several process steps of C01B2203/02 - C01B2203/08 integrated into a single apparatus
• CPC Class Codes: C01B 3/38 using catalysts
• CPC Class Codes: C01B 3/382 Multi-step processes
• CPC Class Codes: C01B 3/583 the reaction being the selective oxidation of carbon monoxide
• 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 fuel cell system is provided which performs simple control of the time until warm-up of the reformer (1) is completed. This fuel cell system comprises a reformer (1) which generates a reformate gas, and a fuel cell (2) which generates power from an oxidizing agent and the reformate gas supplied from the reformer (1). The fuel cell system is provided with a temperature sensor (7) which performs a detection at one position of the temperature immediately before starting or re-starting the reformer (1) and a controller (6) estimating the time to warm-up the reformer (1) based on the detected temperature of the reformer (1).

Claims

1. A fuel cell system, having a reformer (1) which generates a hydrogen-rich reformate gas;

a fuel cell (2) which generates power using an oxidizing agent and the reformate gas supplied from the reformer (1), the fuel cell (2) having a fuel cell stack (16) and a power control circuit (12) for controlling power generation and an output to a load circuit (13); and

a heating device (15) for warming the reformer (1);

the fuel cell system comprising;

a temperature sensor (7) which detects a temperature of the reformer (1) at a single position; and

a controller (6) functioning to;

set a warm-up period of the reformer (1) based on the temperature of the reformer (1) detected immediately before warm-up by the temperature sensor (7); and

control the heating device (15) so that the warm-up operation of the reformer (1) is performed within the warm-up period.

2. The fuel cell system as defined in claim 1, wherein the controller (6) functions to set the warm-up period of the reformer (1) based on a load of the reformer (1) and the temperature detected immediately before the warm-up.

3. The fuel cell system as defined in claim 1, wherein the controller (6) functions to set the warm-up period of the reformer (1) to a warm-up period under maximum load of the reformer (1), based on the detected temperature.

4. The fuel cell system as defined in any one of claim 2 to claim 3, wherein the controller (6) stores a map specifying the warm-up period of the reformer (1) and the temperature detected immediately before the warm-up based on the load of the reformer (1).

5. The fuel cell system as defined in any one of claim 1 to claim 4, wherein the controller (6) further functions to:

set a waiting time based on a target power in the fuel cell (2); and

command the power control circuit (12) to start output of current after the waiting time has elapsed after stopping the warm-up operation in the reformer (1).

6. The fuel cell system as defined in claim 5, wherein the controller (6) stores a map specifying the relation between the target power in the fuel cell (2) and the waiting time.

7. The fuel cell system as defined in any one of claim 1 to claim 6, further comprising a secondary battery (50), wherein power supply source for the load circuit (13) is switched between the fuel cell (2) and the secondary battery (50) depending upon whether the reformer (1) is warming up.

8. The fuel cell system as defined in any one of claim 1 to claim 7, further comprising a bypass passage (20) by which the reformate gas bypasses the fuel cell (2), wherein the reformate gas flows into the bypass passage (20) during the warm-up.

9. The fuel cell system as defined in claim 1, further comprising a heater (22) for heating the fuel cell stack (16) of the fuel cell (2).

10. The fuel cell system as defined in claim 9, further comprising a source (5) of the oxidizing agent and a passage (23) for mixing the oxidizing agent to the reformate gas generated by the reformer (1).

11. A fuel cell system, having a reformer (1) which generates a hydrogen-rich reformate gas;

a fuel cell (2) which generates power using an oxidizing agent and the reformate gas supplied from the reformer (1), the fuel cell (2) having a fuel cell stack (16) and a power control circuit (12) for controlling power generation and an output to a load circuit (13); and

a heating device (15) for warming the reformer (1);

the fuel cell system comprising;

a temperature sensor (7) which detects a temperature of the reformer (1) at a single position; and

a controller (6) functioning to;

set a warm-up period of the reformer (1) based on the temperature of the reformer (1) detected immediately before warm-up;

set a waiting time based on a target power in the fuel cell (2);

control the heating device (15) so that the warm-up operation of the reformer (1) is performed within the warm-up period; and

command the power control circuit (12) to start output of current after the waiting time has elapsed after stopping the warm-up operation in the reformer (1).