Battery state of charge reset

• US 20060091861A1
• Filed: 12/13/2005
• Published: 05/04/2006
• Est. Priority Date: 04/06/2004
• Status: Active Grant

• Current Assignee: Chevron Technology Ventures LLC (Chevron Corp.)
• Original Assignee: Cobasys LLC (Robert Bosch GmbH)
• Inventors: Melichar, Robert J.
• Granted Patent: US 8,427,109 B2
• Time in Patent Office: Days
• US Class Current: 320/132
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/379 for lead-acid batteries
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A battery control module is provided for use with a battery and includes a voltage measuring module that measures battery voltage, a current measuring module that measures battery current, and a state of charge (SOC) module. The SOC module communicates with the current and voltage measuring modules, determines a reset voltage based on the battery current, compares the battery voltage and the reset voltage, and resets a battery SOC based on an outcome of the comparison.

Claims

1. A battery control module for use with a battery, comprising:

a voltage measuring module that measures battery voltage;

a current measuring module that measures battery current; and

a state of charge (SOC) module that communicates with said current and voltage measuring modules, determines a reset voltage based on said battery current, compares said battery voltage and said reset voltage, and resets a battery SOC based on an outcome of said comparison.

2. The battery control module of claim 1 wherein said reset voltage comprises a low reset voltage and a high reset voltage;

and

wherein said comparison comprises a first comparison between said battery voltage and said low reset voltage and a second comparison between said battery voltage and said high reset voltage.

3. The battery control module of claim 1 wherein said SOC module accumulates charge swing while charging said battery, identifies a charge event based on said charge swing, and resets said battery SOC based on said comparison and on identifying said charge event.

4. The battery control module of claim 1 wherein said SOC module accumulates discharge swing while discharging said battery, identifies a discharge event based on said discharge swing, and resets said battery SOC based on said comparison and on identifying said discharge event.

5. The battery control module of claim 2 wherein said SOC module resets said battery SOC to a battery SOC that is based on at least one of said low reset voltage and said high reset voltage.

6. The battery control module of claim 1 wherein said reset voltage is based on a polarization voltage of said battery.

7. The battery control module of claim 6 wherein said SOC module determines said polarization voltage based on a time constant.

8. The battery control module of claim 7 wherein said time constant is based on a magnitude of said battery current.

9. The battery control module of claim 7 wherein said time constant is based on a polarity of said battery current.

10. The battery control module of claim 7 wherein said time constant is based on a previous value of said polarization voltage.

11. The battery control module of claim 1 wherein said SOC module resets said battery SOC further based on whether a magnitude of said battery current exceeds a predetermined threshold.

12. A method for resetting an estimated battery SOC, comprising:

measuring a battery voltage;

measuring a battery current;

determining a reset voltage based on said battery current;

comparing said battery voltage and said reset voltage; and

resetting said battery SOC based on an outcome of said comparing step.

13. The method of claim 12 wherein said reset voltage comprises a low reset voltage and a high reset voltage;

and

wherein said comparing step comprises at least one of a first comparison between said battery voltage and said low reset voltage and a second comparison between said battery voltage and said high reset voltage.

14. The method of claim 12 further comprising:

accumulating charge swing while charging said battery;

identifying a charge event based on said charge swing; and

resetting said battery SOC based on the outcome of said comparing step and an outcome of said identifying step.

15. The method of claim 12 further comprising:

accumulating discharge swing while discharging said battery;

identifying a discharge event based on said discharge swing; and

resetting said battery SOC based on the outcome of said comparing step and an outcome of said identifying step.

16. The method of claim 13 further comprising resetting said battery SOC to a battery SOC that is based on at least one of said low reset voltage and said high reset voltage.

17. The method of claim 12 wherein said reset voltage is based on a polarization voltage of said battery.

18. The method of claim 17 wherein said polarization voltage is based on a time constant.

19. The method of claim 18 wherein said time constant is based on a magnitude of said battery current.

20. The method of claim 18 wherein said time constant is based on a polarity of said battery current.

21. The method of claim 18 wherein said time constant is based on a previous value of said polarization voltage.

22. The method of claim 12 wherein said resetting step is further based on whether a magnitude of said battery current exceeds a predetermined threshold.

23. In a battery control module that determines a battery state-of-charge (SOC) of an associated battery, a method for resetting the battery SOC, comprising:

measuring a battery voltage;

measuring a battery current;

measuring a battery temperature;

selecting a time constant that is based on said battery current;

determining at least one of a low reset voltage and a high reset voltage that are based on said time constant and said battery temperature;

comparing said battery voltage to at least one of said low reset voltage and said high reset voltage; and

resetting said battery SOC based on an outcome of said comparing step.