Battery charge indication methods, battery charge monitoring devices, rechargeable batteries, and articles of manufacture

• US 7,723,958 B2
• Filed: 03/31/2006
• Issued: 05/25/2010
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Lithion Battery Incorporated
• Original Assignee: Valence Technology Incorporated (Lithium Werks B.V.)
• Inventors: Darilek, Christopher
• Primary Examiner(s): Assouad; Patrick J
• Assistant Examiner(s): DIAO, M BAYE
• Application Number:
  US11/394,726
• Publication Number:
  US 20070236183A1
• Time in Patent Office: 1,516 Days
• Field of Search: 320/118, 320/119, 320/120, 320/121, 320/122, 320/123, 320/125, 320/127, 320/132, 320/134, 320/136, 320/DIG.21, 320/DIG.19, 324/427, 324/432, 324/434, 702/63, 702/88, 702/99
• US Class Current: 320/132
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/3828 using current integration
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Battery charge indication methods, battery state of charge monitoring devices, rechargeable batteries, and articles of manufacture are described. According to one aspect, a battery charge indication method includes first determining a state of charge of a battery at a first moment in time using a first method, second determining a state of charge of the battery at a second moment in time using a second method different than the first method, and providing information regarding the state of charge of the battery at the first and second moments in time using information of the first and second determinings.

Claims

1. A battery charge indication method comprising:

first determining a state of charge of a battery at a first moment in time using a first method;

second determining a state of charge of the battery at a second moment in time using a second method different than the first method;

providing information regarding the state of charge of the battery at the first and second moments in time using information of the first and second determining; and

switching between the first method and the second method using the state of charge of the battery.

2. The method of claim 1 further comprising third determining information regarding the state of charge of the battery at a third moment in time by combining information of the first and second methods at the third moment in time.

3. The method of claim 1 wherein first and second determinings comprise monitoring different electrical parameters of the battery during respective ones of the first and second determinings.

4. The method of claim 1 wherein the first determining comprises counting Coulombs of a current of the battery and the second determining comprises monitoring voltage of a cell of the battery.

5. The method of claim 4 further comprising third determining information regarding the state of charge of the battery at a third moment in time by combining information of the first and second methods at the third moment in time.

6. The method of claim 1 further comprising recharging the battery from a first state of charge to a second state of charge greater than the first state of charge, and indicating the state of charge of the battery before and after the recharging.

7. The method of claim 1 wherein at least one of the first and the second determinings comprises accommodating for decreased capacity of the battery.

8. The method of claim 1 wherein at least one of the first and the second determinings comprises determining using a discharge voltage profile of a cell of the battery.

9. The method of claim 1 further comprising monitoring temperature, and wherein at least one of the first and the second determinings comprises determining using the temperature.

10. The method of claim 1 further comprising indicating the information regarding the state of charge of the battery to a user.

11. The method of claim 1 wherein the first and second moments in time occur during respective first and second discharge cycles of the battery comprising a rechargeable battery, and wherein the second determining comprises determining using information obtained during the first discharge cycle.

34. The method of claim 1 wherein one of the first and second determinings comprises determining the state of charge of the battery using information regarding an electrical parameter of the battery and wherein an other of the first and second determinings comprises determining the state of charge of the battery not using information regarding the electrical parameter.

37. The method of claim 1 wherein the switching comprises switching between use of the first method and use of the second method to determine the state of charge of the battery.

12. A battery charge indication method comprising:

monitoring a battery during discharging of the battery in a first discharge cycle;

using the monitoring, generating information regarding the discharging of the battery in the first discharge cycle;

recharging the battery after the discharging of the battery in the first discharge cycle;

providing information regarding a state of charge of the battery during discharging of the battery in a second discharge cycle after the recharging; and

wherein the providing the information regarding the state of charge comprises providing using the information regarding the discharging of the battery in the first discharge cycle.

13. The method of claim 12 further comprising providing information regarding the state of charge of the battery during discharging of the battery in the first discharge cycle, and wherein the providings of the information during the discharging of the battery in the first and second discharge cycles comprises providing using respective ones of a plurality of different methods for calculating the state of charge.

14. The method of claim 12 further comprising monitoring the battery during discharging of the battery in the second discharge cycle, and wherein the providing the information regarding the state of charge of the battery comprises providing using information of the monitoring the battery during discharging of the battery in the second discharge cycle.

15. The method of claim 12 wherein the monitoring of the battery comprises monitoring a plurality of different electrical parameters of the battery at different moments in time.

16. A battery charge monitoring device comprising:

an interface configured to couple with a battery;

processing circuitry coupled with the interface and configured to provide information regarding a state of charge of the battery at a plurality of different moments in time, wherein the processing circuitry is configured to use a first method to determine the information regarding the state of charge at a first moment in time and to use a second method different than the first method to provide the information regarding the state of charge at a second moment in time; and

wherein the processing circuitry is configured to use a third method to provide information regarding the state of charge of the battery at a third moment in time, wherein the third method is different than the first and second methods and uses information obtained using the first and the second methods at the third moment in time.

17. The device of claim 16 wherein the processing circuitry is configured to monitor respective ones of a plurality of different electrical parameters of the battery during the usage of the first method and the second method.

18. The device of claim 16 wherein the processing circuitry is configured to monitor a current of the battery during the use of the first method and to monitor a voltage of a cell of the battery during the use of the second method.

19. The device of claim 18 wherein the processing circuitry is configured to compare the voltage of the cell with a discharge voltage profile of the cell to determine information regarding the state of charge at the second moment in time.

20. The device of claim 16 wherein the processing circuitry is configured to switch from use of the first method to use of the second method responsive to the state of charge of the battery.

21. The device of claim 16 wherein the processing circuitry is configured to switch from use of the first method to use of the second method responsive to the state of charge of the battery reaching a threshold.

22. The device of claim 16 wherein the processing circuitry is configured to monitor temperature and to adjust information regarding the state of charge according to the temperature.

23. A rechargeable battery comprising:

at least one rechargeable cell configured to store electrical energy and to be electrically discharged during a discharged mode of operation and to be electrically charged during a charged mode of operation;

a monitoring device coupled with the at least one rechargeable cell and configured to implement a first method to provide information regarding the state of charge of the rechargeable cell at a first moment in time and to implement a second method to provide information regarding the state of charge of the rechargeable cell at a second moment in time, wherein the first and second methods are different; and

wherein the monitoring device is configured to accommodate for decreased capacity of the rechargeable cell during implementation of at least one of the first and second methods to provide the information regarding the state of charge.

24. The battery of claim 23 wherein the monitoring device is configured to implement a third method to provide information regarding the state of charge of the rechargeable cell at a third moment in time, wherein the third method is different than the first and second methods and uses information provided by the first and the second methods at the third moment in time.

25. The battery of claim 23 wherein the monitoring device is configured to monitor different electrical parameters of the rechargeable cell during respective implementations of the first method and the second method.

26. The battery of claim 23 wherein the monitoring device is configured to change from implementing the first method to the second method using the state of charge of the rechargeable cell.

27. A battery charge indication method comprising:

first determining a state of charge of a battery at a first moment in time using a first method;

second determining a state of charge of the battery at a second moment in time using a second method different than the first method;

providing information regarding the state of charge of the battery at the first and second moments in time using information of the first and second determining; and

wherein the first and second moments in time occur during respective first and second discharge cycles of the battery comprising a rechargeable battery, and wherein the second determining comprises determining using information obtained during the first discharge cycle.

28. A battery charge monitoring device comprising:

an interface configured to couple with a battery;

processing circuitry coupled with the interface and configured to provide information regarding a state of charge of the battery at a plurality of different moments in time, wherein the processing circuitry is configured to use a first method to determine the information regarding the state of charge at a first moment in time and to use a second method different than the first method to provide the information regarding the state of charge at a second moment in time; and

wherein the processing circuitry is configured to monitor a current of the battery during the use of the first method and to monitor a voltage of a cell of the battery during the use of the second method.

29. A battery charge monitoring device comprising:

an interface configured to couple with a battery;

processing circuitry coupled with the interface and configured to provide information regarding a state of charge of the battery at a plurality of different moments in time, wherein the processing circuitry is configured to use a first method to determine the information regarding the state of charge at a first moment in time and to use a second method different than the first method to provide the information regarding the state of charge at a second moment in time; and

wherein the processing circuitry is configured to use a discharge voltage profile of a cell of the battery to determine information regarding the state of charge at the second moment in time.

30. The device of claim 29 wherein the processing circuitry is configured to compare a voltage of the cell with the discharge voltage profile of the cell to determine the information regarding the state of charge at the second moment in time.

31. A battery charge monitoring device comprising:

an interface configured to couple with a battery;

processing circuitry coupled with the interface and configured to provide information regarding a state of charge of the battery at a plurality of different moments in time, wherein the processing circuitry is configured to use a first method to determine the information regarding the state of charge at a first moment in time and to use a second method different than the first method to provide the information regarding the state of charge at a second moment in time; and

wherein the processing circuitry is configured to switch from use of the first method to use of the second method using the state of charge of the battery.

32. The device of claim 31 wherein the processing circuitry is configured to switch from use of the first method to use of the second method responsive to the state of charge of the battery reaching a threshold.

35. The device of claim 31 wherein the processing circuitry is configured to use information regarding an electrical parameter of the battery during use of one of the first and second methods and the processing circuitry is configured to not use information regarding the electrical parameter of the battery during use of an other of the first and second methods.

33. A battery charge monitoring device comprising:

an interface configured to couple with a battery;

processing circuitry coupled with the interface and configured to provide information regarding a state of charge of the battery at a plurality of different moments in time, wherein the processing circuitry is configured to use a first method to determine the information regarding the state of charge at a first moment in time and to use a second method different than the first method to provide the information regarding the state of charge at a second moment in time; and

wherein the processing circuitry is configured to monitor an environment about the battery and to adjust information regarding the state of charge using the monitoring.

36. The device of claim 33 wherein the processing is configured to monitor temperature of the environment to monitor the environment about the battery and to adjust the information regarding the state of charge using the temperature of the environment.