Fuel cell vehicle

• US 6,408,966 B1
• Filed: 07/23/1998
• Issued: 06/25/2002
• Est. Priority Date: 07/23/1997
• Status: Expired due to Fees

• Current Assignee: NuCellSys GmbH (Mercedes-Benz Group AG)
• Original Assignee: Xcellsis GmbH
• Inventors: Hornburg, Gerald, Benz, Uwe, Tillmetz, Werner
• Primary Examiner(s): Mai, Lanna
• Assistant Examiner(s): PHAN, HAU VAN
• Application Number:
  US09/120,801
• Time in Patent Office: 1,433 Days
• Field of Search: 180/65.1, 180/165, 180/65.2, 180/65.3, 180/65.4, 180/65.6, 180/65.7, 180/65.8, 429/13, 429/19, 417/313, 416/60, 320/102, 322/13, 318/139
• US Class Current: 180/65.1
• CPC Class Codes: B60L 58/30 for monitoring or controlling fuel cells
• CPC Class Codes: B60L 58/33 by cooling
• CPC Class Codes: B60L 58/34 by heating
• CPC Class Codes: B60L 7/10 Dynamic electric regenerative braking B60L7/22 takes precedence
• CPC Class Codes: H01M 2250/20 Fuel cells in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 8/04022 Heating by combustion
• CPC Class Codes: H01M 8/04029 Heat exchange using liquids
• CPC Class Codes: H01M 8/04089 of gaseous reactants
• CPC Class Codes: H01M 8/04156 with product water removal
• CPC Class Codes: H01M 8/0612 from carbon-containing material
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A fuel cell vehicle comprises an electric drive system and a fuel cell system for providing electric energy for the drive system. According to the invention, the electric drive system is set up for regenerating braking energy, and devices are provided for the direct utilization of the regenerated braking energy in at least one energy-consuming component of the fuel cell system. This direct braking energy utilization in the fuel cell system increases the degree of energy utilization without the requirement of a separate intermediate energy storage device for the intermediate storing of regenerated braking energy.

Claims

1. A fuel cell vehicle, comprising:

an electric drive system having at least one electric motor and being adapted for regenerating braking energy, said electric drive system being connected to a system control;

a fuel cell system comprising a fuel cell stack for providing electric energy to the electric drive system and connected to the control system by electric connection lines;

a compressor coupled in fluid communication with the fuel cell stack for compressing oxygen-containing gas for the fuel cell stack and adapted to be operated by regenerated braking energy from the electric drive system; and

a pressure accumulator connected to a compressor outlet for storing additionally-compressed oxygen-containing gas from the compressor.

2. A fuel cell vehicle according claim 1, wherein the fuel cell system further comprises:

a reforming system with a reforming reactor unit and a reactor heater, said reforming system being coupled in fluid communication with the fuel cell stack,

wherein the reactor heater is adapted to be operated by regenerated braking energy from the electric drive system, thereby providing additional heating of the reforming reactor unit.

3. A fuel cell vehicle according to claim 1, wherein the fuel cell system further comprises:

a reforming system with a reforming reactor unit, an evaporator, and a heater,

wherein the heater is adapted to be operated by regenerated braking energy from the electric drive system, thereby providing additional heating of the evaporator.

7. A fuel cell vehicle according to claim 1, which does not contain a storage battery for regenerated braking energy.

4. A fuel cell vehicle, comprising:

an electric drive system having at least one electric motor and being adapted for regenerating braking energy, said electric drive system being connected to a system control;

a fuel cell system for providing electric energy to the drive system comprising a reforming system with a reforming reactor unit, said fuel cell system being connected to the control system by electric connection lines;

a reformate gas compressor that is arranged downstream of and is coupled in fluid communication with the reforming reactor unit and is adapted to be operated by regenerated braking energy; and

a reformate gas pressure accumulator being coupled in fluid communication with the reformate gas compressor for the intermediate storage of reformate gas compressed by the reformate gas compressor.

5. A fuel cell vehicle, comprising:

an electric drive system having at least one electric motor and being adapted for regenerating braking energy, said electric drive system being connected to a system control;

fuel cell system for providing electric energy to the drive system comprising a reforming system having a reforming reactor unit and an evaporator connected in front of the reforming reactor unit, said fuel cell system being connected to the control system by electric connection lines;

a vapor accumulator connected to an evaporator outlet,

wherein the evaporator is adapted to be operated by regenerated braking energy from the electric drive system, thereby producing excess vapor to be intermediately stored in the vapor accumulator.

6. A fuel cell vehicle, comprising:

an electric drive system having at least one electric motor and being adapted for regenerating braking energy, said electric drive system being connected to a system control;

a fuel cell system comprising a fuel cell stack for providing electric energy to the drive system, said fuel cell system being connected to the control system by electric connection lines; and

means for directly utilizing the regenerated braking energy in at least one energy-consuming component of the fuel cell system, wherein said utilizing means is selected from the group consisting of;

a pressure accumulator connected to an air compressor outlet of a compressor coupled in fluid communication with the fuel cell stack;

a reformate gas pressure accumulator for the intermediate storage of reformate gas compressed by a reformate gas compressor, said reformate gas compressor being coupled in fluid communication with a reformation reactor unit; and

a vapor accumulator connected to an evaporator outlet of an evaporator coupled in fluid communication with the reformation reactor unit.

8. A method of operating an energy-consuming component of a fuel cell vehicle, comprising:

directing regenerated braking energy from an electric drive system to an air compressor;

compressing oxygen-containing gas; and

intermediately storing the compressed oxygen-containing gas in a pressure accumulator connected to an air compressor outlet.

9. A method according to claim 8, further comprising:

directing regenerated braking energy from the electric drive system to a heater; and

heating a reforming reactor unit.

10. A method according to claim 8, further comprising:

directing regenerating braking energy from the electric drive system to a heater; and

heating an evaporator.

11. A method for operating an energy-consuming component of a fuel cell vehicle, comprising:

directing regenerated braking energy from an electric drive system to a reformate gas compressor arranged downstream of a reforming reactor unit;

compressing reformate gas; and

intermediately storing the compressed reformate gas in a reformate gas pressure accumulator.

12. A method for operating an energy-consuming component of a fuel cell vehicle, comprising:

directing regenerated braking energy from an electric drive system to an evaporator connected in front of a reforming reactor unit; and

producing excess vapor in the evaporator; and

intermediately storing the excess vapor in a vapor accumulator.