System and method for charging a rechargeable battery

• US 8,405,361 B2
• Filed: 09/21/2007
• Issued: 03/26/2013
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: Omnitracs LLC (Solera Holdings Incorporated)
• Original Assignee: Qualcomm, Inc.
• Inventors: Richards, Anthony M., Hardgrove, Charles E., Molesworth, William Hugh
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): PIGGUSH, AARON C
• Application Number:
  US11/859,074
• Publication Number:
  US 20090079394A1
• Time in Patent Office: 2,013 Days
• Field of Search: 320/125, 320/132, 320/134, 320/138
• US Class Current: 320/138
• CPC Class Codes: H02J 2207/40 adapted for charging from various sources, e.g. AC, DC or multivoltage
• CPC Class Codes: H02J 7/0071 with a programmable schedule

Abstract

The present invention includes a system and method of charging a rechargeable battery. The system can further include a processor that is adapted to control one of the high power charger or the low power charger to charge the battery in response to the high power input voltage relative to a predetermined high power voltage value and the low power input voltage relative to a predetermined low power voltage value. The method can include the steps of determining a high power input voltage of the high power source, determining a low power input voltage of the low power source, causing a high power charger to charge the battery in response to a sufficient high power input voltage, and causing a low power charger to charge the battery in response to an insufficient high power input voltage and a sufficient low power input voltage.

Claims

1. A method for charging a rechargeable battery through one of a high power source or a low power source, the method comprising:

causing a high power charger to charge the battery in response to a corresponding high power input voltage from the high power source comprising a sufficient high power input voltage;

causing a low power charger to charge the battery in response to an insufficient high power input voltage and a corresponding low power input voltage from the low power source comprising a sufficient low power input voltage;

accumulating the amp-hours-out of the battery for more than one time period in which the battery is in a discharge state, including a previous amp-hours-out corresponding to a first time period and a new amp-hours-out corresponding to a second time period;

calculating the aggregate of the amp-hours-out of the battery as a sum of the previous amp-hours-out and the new amp-hours-out;

determining a battery capacity based on the aggregate of an amp-hours-out from the battery;

determining a fast charge required based on the battery capacity, wherein the fast charge is at a higher voltage relative to a normal charge; and

wherein causing the low power charger to charge the battery further comprises setting the low power charger to a fast charge state to provide the fast charge required.

2. The method of claim 1, further comprising causing the low power charger to charge the battery in response to the high power source being disconnected from the battery during a charging phase, such that the low power charger resumes charging the battery from an intermediate charge state of the battery.

3. The method of claim 1, wherein causing the high power charger to charge the battery further comprises causing the high power charger to charge the battery according to a high power algorithm.

4. The method of claim 3, wherein the high power algorithm comprises:

setting the high power charger to a high power fast charge state;

ending the high power fast charge state in response to a charger current value being less than a minimum current value;

setting the high power charger to an overcharge state in response to the charger current value decreasing below the minimum current value; and

setting the high power charger to a float charge state in response to ending the overcharge state or exceeding a maximum time allowed for the high power fast charge state.

5. The method of claim 1, wherein causing the low power charger to charge the battery further comprises causing the low power charger to charge the battery according to a low power algorithm.

6. The method of claim 5, wherein the low power algorithm comprises:

determining a charge rate of the fast charge required in response to a previous charging routine; and

ending the fast charge state in response to the aggregate of the amp-hours-out of the battery being replaced by an amp-hours-in provided by the low power charger.

7. The method of claim 6, wherein the aggregate of the amp-hours-out of the battery comprises an aggregate of amp-hours provided by the battery to one or more peripherals.

8. The method of claim 7, wherein the aggregate of the amp-hours-out of the battery further comprises a prior aggregation of amp-hours provided by the battery to the one or more peripherals.

9. The method of claim 1, further comprising:

discharging the battery in response to a transition between causing the high power charger to charge the battery and causing the low power charger to charge the battery.

10. The method of claim 1, further comprising:

measuring a peak minimum voltage of the battery; and

wherein determining the battery capacity is further based on the peak minimum voltage of the battery.

11. The method of claim 1, wherein determining the battery capacity is further based on a temperature of the battery.

12. The method of claim 1, further comprising:

terminating charging of the battery by the high power charger or the low power charger;

compiling a charging history of the battery in response to terminating the charging of the battery; and

determining a new charging rate for a next charging of the battery based on the charging history.

13. The method of claim 12, further comprising:

calculating a charge out value as a function of a minimum battery voltage and a temperature of the battery;

wherein compiling the charging history of the battery further comprises determining a calculated aggregate of the amp-hours-out of the battery; and

resetting a value of the aggregate of the amp-hours-out of the battery to the charge out value if the charge out value is larger than the calculated aggregate of the amp-hours-out of the battery.

14. A system for charging a battery, comprising:

a high power charger connected to a high power source defining a high power input voltage for charging a battery;

a low power charger connected to a low power source defining a low power input voltage for charging the battery; and

a processor connected to the high power charger and the low power charger, the processor adapted to accumulate the amp-hours-out of the battery for more than one time period in which the battery is in a discharge state, including a previous amp-hours-out corresponding to a first time period and a new amp-hours-out corresponding to a second time period, calculate the aggregate of the amp-hours-out of the battery as a sum of the previous amp-hours-out and the new amp-hours-out, control the high power charger to charge the battery in response to the high power input voltage comprising a sufficient high power input voltage, wherein the processor is adapted to control the low power charger to charge the battery in response to the high power input voltage comprising an insufficient high power input voltage and the low power input voltage comprising a sufficient low power input voltage;

wherein the processor is further adapted to determine a battery capacity based on the aggregate of an amp-hours-out from the battery, and to determine a fast charge required based on the battery capacity, wherein the fast charge is at a higher voltage relative to a normal charge; and

wherein the processor is further adapted to set the low power charger to a fast charge state to provide the fast charge required when selecting the low power charger to charge the battery.

15. The system of claim 14, wherein the processor is further adapted to control the low power charger to charge the battery in response to the high power source being disconnected from the battery during a charging phase, such that the low power charger resumes charging the battery from an intermediate charge state of the battery.

16. The system of claim 14, wherein the processor is further adapted to control the high power charger to charge the battery according to a high power algorithm.

17. The system of claim 16, wherein the high power algorithm includes:

setting the high power charger to a high power fast charge state;

ending the high power fast charge state in response to a charger current value being less than a minimum current value;

setting the high power charger to an overcharge state in response to the charger current value decreasing below the minimum current value; and

setting the high power charger to a float charge state in response to one of ending the high power fast charge state or the overcharge state.

18. The system of claim 14, wherein the processor is further adapted to control the low power charger to charge the battery according to a low power algorithm.

19. The system of claim 18, wherein the low power algorithm includes:

determining a charge rate of the fast charge required in response to a previous charging routine; and

ending the fast charge state in response to the aggregate of the amp-hours-out of the battery being replaced by an amp-hours-in provided by the low power charger.

20. The system of claim 19, wherein the aggregate of the amp-hours-out of the battery comprises an aggregate of amp-hours provided by the battery to one or more peripherals.

21. The system of claim 20, wherein the aggregate of the amp-hours-out of the battery further comprises a prior aggregation of amp-hours provided by the battery to the one or more peripherals.

22. The system of claim 14, wherein the processor is further adapted to transition through a discharge state in response to a transition between controlling the high power charger to charge the battery and controlling the low power charger to charge the battery.

23. A computer program product, comprising:

a non-transitory computer-readable medium comprising;

code for causing a processor to control a high power charger to charge a battery in response to a corresponding high power input voltage comprising a sufficient high power input voltage;

code for causing the processor to control a low power charger to charge the battery in response to the high power input voltage comprising an insufficient high power input voltage and a corresponding low power input voltage comprising a sufficient low power input voltage;

code for causing the processor to accumulate the amp-hours-out of the battery for more than one time period in which the battery is in a discharge state, including a previous amp-hours-out corresponding to a first time period and a new amp-hours-out corresponding to a second time period;

code for causing the processor to calculate the aggregate of the amp-hours-out of the battery as a sum of the previous amp-hours-out and the new amp-hours-out;

code for causing the processor to determine a battery capacity based on an aggregate of the amp-hours-out from the battery;

code for causing the processor to determine a fast charge required based on the battery capacity, wherein the fast charge is at a higher voltage relative to a normal charge; and

code for causing the processor to set the low power charger to a fast charge state to provide the fast charge required when selecting the low power charger to charge the battery.

24. The product of claim 23, wherein the non-transitory computer-readable medium further comprises code for causing the processor to control the low power charger to charge the battery in response to the high power source being disconnected from the battery during a charging phase, such that the low power charger resumes charging the battery from an intermediate charge state of the battery.

25. The product of claim 23, wherein the non-transitory computer-readable medium further comprises code for causing the processor to control the high power charger to charge the battery according to a high power algorithm.

26. The product of claim 25, wherein the high power algorithm includes:

setting the high power charger to a high power fast charge state;

ending the high power fast charge state in response to a charger current value being less than a minimum current value;

setting the high power charger to an overcharge state in response to the charger current value decreasing below the minimum current value; and

setting the high power charger to a float charge state in response to one of ending the high power fast charge state or the overcharge state.

27. The product of claim 23, wherein the non-transitory computer-readable medium further comprises code for causing the processor to control the low power charger to charge the battery according to a low power algorithm.

28. The product of claim 27, wherein the low power algorithm includes:

determining a charge rate of the fast charge required in response to a previous charging routine; and

ending the fast charge state in response to the aggregate of the amp-hours-out of the battery being replaced by an amp-hours-in provided by the low power charger.

29. The product of claim 28, wherein the aggregate of the amp-hours-out of the battery comprises an aggregate of amp-hours provided by the battery to one or more peripherals.

30. The product of claim 29, wherein the aggregate of the amp-hours-out of the battery further comprises a prior aggregation of amp-hours provided by the battery to the one or more peripherals.

31. The product of claim 29, wherein the non-transitory computer-readable medium further comprises code for causing the processor to discharge the battery in response to a transition between controlling the high power charger to charge the battery and controlling the low power charger to charge the battery.

32. An apparatus for charging a rechargeable battery through one of a high power source or a low power source, comprising:

means for causing a high power charger to charge the battery in response to a sufficient high power input voltage from the high power source;

means for causing a low power charger to charge the battery in response to an insufficient high power input voltage from the high power source and a sufficient low power input voltage from the low power source;

means for accumulating the amp-hours-out of the battery for more than one time period in which the battery is in a discharge state, including a previous amp-hours-out corresponding to a first time period and a new amp-hours-out corresponding to a second time period;

means for calculating the aggregate of the amp-hours-out of the battery as a sum of the previous amp-hours-out and the new amp-hours-out;

means for determining a battery capacity based on an aggregate of an amp-hours-out from the battery;

means for determining a fast charge required based on the battery capacity, wherein the fast charge is at a higher voltage relative to a normal charge; and

wherein the means for causing the low power charger to charge the battery further comprises means for setting the low power charger to a fast charge state to provide the fast charge required.