Fuel cell system

• US 7,862,945 B2
• Filed: 06/05/2006
• Issued: 01/04/2011
• Est. Priority Date: 03/04/2004
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Saito, Tomohiro, Kashiwagi, Hideki
• Primary Examiner(s): Ryan; Patrick
• Assistant Examiner(s): APICELLA, KARIE O
• Application Number:
  US11/446,163
• Publication Number:
  US 20060222917A1
• Time in Patent Office: 1,674 Days
• Field of Search: 429/23
• US Class Current: 429/430
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/34 by heating
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• 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 8/04679 of fuel cell stacks
• CPC Class Codes: H01M 8/04738 of auxiliary devices, e.g. reformer, compressor, burner
• CPC Class Codes: H01M 8/04873 of the individual fuel cell
• CPC Class Codes: H01M 8/04947 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A fuel cell system according to the present invention has a movement drive device (load) (2), a fuel cell (10) for supplying electric power to the drive device, an electric power storing device (31) consuming electric power equivalent to the consumption power of the drive device, and an electronic control unit (connection control unit) (4) for controlling the connection of the fuel cell to the drive device. Before the fuel cell is connected to the drive device by the control of the electronic control unit, the fuel cell is made to generate electric power equivalent to the consumption power of the drive device, and the generated power is supplied to the electric power storing device. When a fuel cell voltage at the time of supply of the electric power to the electric power storing device is not less than a specified value, the connection between the fuel cell and the drive device is permitted.

Claims

1. A fuel cell system comprising:

a load;

a fuel cell for supplying electric power to the load;

an electric power storing device that can be charged with at least an electric power equivalent to a consumption power of the load; and

a connection control unit for controlling a connection of the fuel cell to the load,

wherein the connection control unit is programmed to cause the fuel cell to generate electric power equivalent to the consumption power of the load, and confirm activation and judge whether the connection to the load can be permitted before connecting the fuel cell to the load.

2. The fuel cell system according to claim 1, wherein when the fuel cell is activated and before the connection control unit connects the fuel cell to the load, the fuel cell is made to generate electric power equivalent to the consumption power of the load, and the generated power is supplied to the electric power storing device.

3. The fuel cell system according to claim 2, wherein the electric power equivalent to the consumption power of the load is the electric power equivalent to a maximum consumption power of the load.

4. The fuel cell system according to claim 1, further comprising a control unit for controlling the fuel cell in order to generate electric power that can be used to charge the electric power storing device.

5. The fuel cell system according to claim 4, wherein the control unit calculates a maximum permissible charge power of the electric power storing device based on at least a voltage of the electric power storing device, and controls the fuel cell according to a maximum charge power.

6. The fuel cell system according to claim 1, further comprising a voltage detecting device for detecting a voltage of the fuel cell,

wherein the connection control unit judges whether the fuel cell voltage detected by the voltage detecting device at a time of supply of the electric power to the electric power storing device is equal to or more than a specified value;

and if the fuel cell voltage is equal to or more than the specified value, the connection control unit permits the connection of the fuel cell to the load.

7. The fuel cell system according to claim 6, wherein the voltage detecting device detects each cell voltage of the fuel cell.

8. A vehicle equipped with the fuel cell system according to claim 3, wherein the load includes a vehicle movement drive device, and the electric power equivalent to the maximum consumption power of the load is the electric power equivalent to the maximum consumption power of the vehicle movement drive device after its activation.