System and method for charging a battery

• US 20030193311A1
• Filed: 04/02/2003
• Published: 10/16/2003
• Est. Priority Date: 04/13/2002
• Status: Abandoned Application

• Current Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Original Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Konrad, Gerhard, Spier, Bernd, Niehues, Michael
• Application Number:
  US10/405,741
• Publication Number:
  US 20030193311A1
• Time in Patent Office: Days
• US Class Current: 320/103
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 7/1438 in combination with power supplies for loads other than batteries
• 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: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A system and a method are used for charging a battery which is connected to intermittently operated devices for providing power required for charging, such as an engine-driven generator in a motor vehicle, for example. In order to provide the battery with additional charge, a fuel cell system is also used. The battery may be kept at a minimum specified state of charge, for example, by the fuel cell system. Discharge by stand-by currents or leakage currents may be compensated or maintenance charge may be provided to the approximately fully charged battery to extend its service life.

Claims

1. A battery system comprising:

a battery;

at least one intermittently operated device connected to the battery for providing power required for charging the battery; and

an additional fuel cell system connected to the battery for providing power for an additional charge to the battery.

2. The system as recited in claim 1 wherein the fuel cell system has an electric power output of less than 500 W.

4. The system as recited in claim 1 wherein the fuel cell system includes a fuel tank and at least one fuel cell, the fuel cell being self-breathing below a predetermined power output, the fuel tank being designed such that fuel reaches an area of an anode of the fuel cell without aid from a delivery device.

5. The system as recited in claim 4 wherein the fuel tank is a cartridge containing pressurized fuel.

6. The system as recited in claim 4 wherein the at least one fuel cell is a PEM fuel cell operated using hydrogen.

7. The system as recited in claim 4 wherein the at least one fuel cell is a methanol fuel cell.

8. The system as recited in claim 7 wherein the fuel tank is situated above the anode so that gravity delivers the fuel to the area of the anode.

9. The system as recited in claim 1 wherein the fuel cell system includes a blower for assisting air supply when the fuel cell system operates above a predetermined electric power.

10. The system as recited in claim 1 wherein the battery has a capacity of more than 10 Ah.

3. The system as recited in claim 3 wherein the electric power output is less than 200 W.

11. A method of providing a battery, connected to an intermittently operated device for providing power required for charging the battery, with additional charge, the method comprising:

using a fuel cell system to providing the battery with an additional charge when devices for providing the power required for charging the battery are not operating.

12. The method as recited in claim 11 wherein the battery is provided with the additional charge so that stand-by currents, leakage currents and self-discharge are compensated to maintain a specified minimum state of charge.

13. The method as recited in claim 11 wherein the battery is provided with the additional charge as a maintenance charge.

14. The method as recited in claim 11 further comprising using the intermittently operated device to charge the battery.

15. The method as recited in claim 11 further comprising providing the battery in a vehicle, the vehicle being one of a land vehicle, watercraft, or aircraft.

16. The method as recited in claim 11 wherein the vehicle is an engine- or motor-driven vehicle.

17. The method as recited in claim 15 wherein the additional charge is a maintenance charge.

18. A vehicle battery system for a land vehicle, watercraft or aircraft comprising:

a battery;

at least one intermittently operated device connected to the battery for providing power required for charging the battery; and

an additional fuel cell system connected to the battery for providing power for an additional charge to the battery