Battery gauging device during battery charging

• US 6,344,731 B2
• Filed: 12/15/2000
• Issued: 02/05/2002
• Est. Priority Date: 12/18/1999
• Status: Expired due to Term

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Woo Seog
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US09/736,193
• Publication Number:
  US 20010004202A1
• Time in Patent Office: 417 Days
• Field of Search: 320/125, 320/132, 320/134, 320/137
• US Class Current: 320/132
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]

Abstract

Disclosed is a battery gauging device during a battery charging, which is capable of gauging the charged capacity during a battery charging in a terminal. The device according to the invention comprises a charger for converting an AC voltage to a DC voltage, and outputting the converted voltage, a battery pack including a battery for charging an electric charge, first switching means for switching on/off the DC voltage, and second switching means switched on/off in accordance with a battery charge enable (BCE) signal so as to temporarily discharge the charged capacity during the battery charging, and a terminal including a battery gauging section for gauging a charged capacity inputted from the battery pack and a microprocessor for outputting the BCE signal to the switching means, and displaying the gauged value on a display section. According to the invention, the DC voltage inputted from the charger to the battery pack is charged in the battery, but is regularly interrupted in the course of the battery charging so as to temporarily discharge the charged capacity, thereby realizing an exact display of the charged capacity on the terminal even during the battery charging.

Claims

1. A battery gauging device, comprising:

a charger to convert an AC voltage to a DC voltage, and to output the converted DC voltage;

a battery pack including a battery coupled to receive an electric charge from the charger, a first switch to switch on/off the DC voltage from the charger, and a second switch coupled to receive a battery charge enable (BCE) signal and configured to switch on/off in accordance with a state of the BCE signal to interrupt the battery charging and discharge the charged capacity of the battery for a prescribed period of time; and

a telecommunication terminal having a battery gauging section configured to measure a level of charge of the battery pack, and a microprocessor coupled to provide the BCE signal to the second switch, wherein the telecommunication terminal is configured to display the measured value of the battery charge on a display section of the telecommunication terminal.

2. The battery gauging device of claim 1, wherein the battery pack further comprises:

a charging/discharging controller to control charging and discharging of the battery and to protect circuitry of the battery gauging device by controlling the switching on/off of the first switch to control a supply of the DC voltage inputted from the charger; and

a temperature detection circuit coupled to a ground terminal of the battery to detect a temperature of the battery, convert the detected temperature value to an electric signal, and output the converted electric signal.

3. The battery gauging device of claim 1, wherein the telecommunication terminal further comprises a system electric power section coupled to receive an output power from the battery pack and provide electric power to elements of the communication terminal, and output a voltage for battery gauging to the battery gauging section.

4. The battery gauging device of claim 1, wherein the first and the second switch each comprise a field effect transistor.

5. The battery gauging device of claim 1, wherein the second switch is coupled between the first switch and a positive terminal of the battery.

6. The battery gauging device of claim 1, wherein the microprocessor controls the second switch by outputting the BCE signal to the second switch at prescribed intervals.

7. The battery gauging device of claim 6, wherein the prescribed intervals of the BCE signal output from the microprocessor has a cycle in which a switched-on time is longer than a switched-off time of the second switch.

8. The battery gauging device of claim 6, wherein when the BCE signal is received by the second switch, the second switch prevents the electric charge from the charger from passing to the battery so that the battery gauging section can determine the level of charge of the battery.

9. The battery gauging device of claim 1, wherein the output voltage of the battery pack inputted to the communication terminal is provided by one of the DC voltage inputted from the charger to the battery pack when the first and second switches are switched on and the existing battery charge when the second switch is switched off.

10. The battery gauging device of claim 9, wherein when the output voltage of the battery pack is provided by the existing battery charge, the battery gauging section can determine an accurate level of charge of the battery.

11. The battery gauging device of claim 1, wherein the battery gauging section converts the charged capacity of the battery inputted from the battery pack to a digital signal, and outputs the converted digital signal to the microprocessor.

12. The battery gauging device of claim 1, wherein the telecommunication terminal receives and detects the charged capacity of the battery.

13. The battery gauging device of claim 1, wherein the telecommunication terminal is a mobile telecommunication terminal using at least one chargeable battery.

14. A method of measuring a level of charge in a battery of a mobile communication terminal during the charging process, comprising:

receiving a DC charging voltage by a battery pack, the battery pack having first and second switches, a battery, and a charging/discharging controller;

monitoring the level of charge of the battery by the charging/discharging controller, and switching off the first switch to interrupt the charging process when the level of charge reaches a certain value;

providing a battery charge enable (BCE) signal from a microcontroller of the mobile communication terminal to the second switch, the BCE having one of a first state and a second state to control an operation of the second switch, wherein the first state of the BCE signal causes the second switch to interrupt the DC voltage charging the battery, and wherein the second state of the BCE signal causes the second switch to provide the DC voltage to the battery to charge the battery; and

measuring a level an output voltage of the battery when the second switch has interrupted the DC voltage to the battery.

15. The method of claim 14, wherein when the second switch interrupts the DC voltage to the battery, the battery begins discharging able tinged to the mobile communication terminal.

16. The method of claim 15, wherein a battery gauging section of the mobile communication terminal measures a level the output voltage of the battery when the second switch has interrupted the DC voltage to the battery, and wherein a display section of the mobile communication terminal displays the measured level of the output voltage of the battery.

17. The method of claim 14, wherein the charging/discharging controller further protects circuits of the battery pack by preventing excess discharging of the battery.

18. The method of claim 14, wherein the microcontroller of the mobile communication terminal is directly coupled to the second switch to provide the BCE signal.

19. The method of claim 14, wherein the mobile communication terminal is provided with the DC charging voltage when the second switch is configured to provide the DC voltage to the battery to charge the battery.

20. A mobile communication terminal, comprising:

a battery pack including a battery coupled to receive an electric charge from a charger, a first switch to switch the DC voltage from the charger on or off in accordance with an output of a controller of the battery pack, and a second switch coupled to directly receive a battery charge enable (BCE) signal from a microproccesor of the mobile communication terminal and configured to switch the DC voltage from the charger on or off in accordance with a state of the BCE signal; and

a battery gauging device configured to measure a level of charge in the battery when the second switch has switched the DC voltage to the battery off and display the measured level of charge on a display section of the mobile communication terminal.