System and method for battery calibration in portable computing devices

• US 7,492,127 B2
• Filed: 01/07/2005
• Issued: 02/17/2009
• Est. Priority Date: 01/07/2005
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Zelinski, Timothy B., Kropp, Darren, Conticello, Thomas
• Primary Examiner(s): Tso; Edward
• Application Number:
  US11/031,414
• Publication Number:
  US 20070216361A1
• Time in Patent Office: 1,502 Days
• Field of Search: 320/107, 320/132, 320/149, 324/426, 324/430, 324/431, 324/433
• US Class Current: 320/132
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition

Abstract

Described is a method which includes a step of initiating a calibration state of a battery status system. The calibration state including charging a battery to a first threshold value; discharging the battery to a second threshold value; and calibrating the battery status system based on the first and second threshold values. Subsequently, the method includes a step of exiting the calibration state. Described is also a portable computing device which includes invades a battery; a controller; and an application executed on the controller for performing calibration of a battery status system of the battery. The application drives the battery to a threshold state and performs the calibration when the battery reaches the threshold state.

Claims

1. A method, comprising:

initiating a calibration state of a battery status system, the calibration state including,

charging a battery to a first threshold value;

discharging the battery to a second threshold value; and

calibrating the battery status system based on the first and second threshold values; and

exiting the calibration state.

2. The method according to claim 1, wherein the battery status system is a coulomb counting system.

3. The method according to claim 1, further comprising:

indicating to a user that the calibration state is one of recommended and required.

4. The method according to claim 1, further comprising:

connecting the battery to an external power source prior to initiating the calibration state.

5. The method according to claim 4, wherein the battery is charged by the external power source.

6. The method according to claim 1, wherein discharging the battery includes removing an external power source from the battery.

7. The method according to claim 1, wherein discharging the battery includes powering at least one peripheral which derives power from the battery.

8. The method according to claim 1, wherein discharging the battery includes disabling an auto-disable mechanism of the battery.

9. The method according to claim 1, wherein the first threshold value is fully charged.

10. The method according to claim 1, wherein the second threshold value is fully discharged.

11. A portable computing device, comprising:

a battery;

a controller; and

an application executed on the controller for performing calibration of a battery status system of the battery, wherein the application charges the battery to a first threshold state;

discharges the battery to a second threshold state; and

performs the calibration when the battery reaches the second threshold state.

12. The portable computing device according to claim 11, wherein the battery status system is a coulomb counting system.

13. The portable computing device according to claim 11, wherein the controller is one of a microcontroller and a complex finite state machine integrated circuit.

14. The portable computing device according to claim 11, wherein the threshold state is a full charge of the battery.

15. The portable computing device according to claim 14, wherein the battery is driven to the full charge by connection to an external power source.

16. The portable computing device according to claim 11, wherein the threshold state is full discharge of the battery.

17. The portable computing device according to claim 16, wherein the battery is driven to the full discharge by one of powering at least one peripheral of the device and disabling an auto-disable mechanism of the device.

18. The portable computing device according to claim 11, wherein the battery comprises one of Li ions, Li polymers, NiCad and NiMh.

19. A battery pack, comprising:

a battery;

a controller; and

an application executed on the controller for performing calibration of a battery status system of the battery, wherein the application charges the battery to a first threshold state;

discharges the battery to a second threshold state; and

performs the calibration when the battery reaches the second threshold state.

20. The battery pack according to claim 19, wherein the battery status system is a coulomb counting system.

21. The battery pack according to claim 19, wherein the controller is one of a microcontroller and a complex finite state machine integrated circuit.

22. The battery pack according to claim 19, wherein the threshold state is a full charge of the battery.

23. The battery pack according to claim 22, wherein the battery is driven to the full charge by connection to an external power source.

24. The battery pack according to claim 19, wherein the threshold state is full discharge of the battery.

25. The battery pack according to claim 24, wherein the battery is driven to the full discharge by one of powering at least one peripheral of the device and disabling an auto-disable mechanism of the device.

26. The battery pack according to claim 19, wherein the battery comprises one of Li ions, Li polymers, NiCad and NiMh.