Apparatus and method for charging a battery pack

• US 9,172,253 B2
• Filed: 12/07/2010
• Issued: 10/27/2015
• Est. Priority Date: 12/28/2009
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: An, Jin-Hong, Kim, Jae-Soon
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): PIGGUSH, AARON C
• Application Number:
  US12/926,728
• Publication Number:
  US 20110156647A1
• Time in Patent Office: 1,785 Days
• Field of Search: 320/110, 320/112, 320/134, 320/145, 320/158, 320/163, 320/125
• US Class Current: 1/1
• CPC Class Codes: H02J 7/00041 in response to measured battery parameters, e.g. voltage, current or temperature profile
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery pack charger and a method of charging a battery pack may properly charge a battery pack regardless of the number of cells in the battery pack. The battery pack charger includes a voltage sensing unit configured to sense an output voltage of the battery pack being charged with a predetermined voltage for a predetermined period, a controller configured to determine a number of cells in the battery pack in accordance with the output voltage, and a power source charge and discharge unit configured to supply a charge voltage to the battery pack, the charge voltage being determined in accordance with the number of cells in the battery pack.

Claims

1. An apparatus for charging a battery pack, comprising:

a voltage sensing unit to sense an output voltage of the battery pack charged with a predetermined voltage for a first period;

a controller to determine a number of cells in the battery pack in accordance with the sensed output voltage; and

a power source charge and discharge unit to supply the predetermined voltage to the battery pack for the first period and to supply a charge voltage to the battery pack for a second period, after the controller has determined the number of cells in the battery pack, the charge voltage being determined in accordance with the number of cells in the battery pack, wherein

the predetermined voltage is set with a constant voltage regardless of the number of cells in the battery pack for the first period, and the charge voltage is changed according to the number of cells in the battery for the second period.

2. The apparatus as claimed in claim 1, wherein the power source charge and discharge unit comprises a power source unit to supply the charge voltage to the battery pack so that a voltage level of the charge voltage supplied to the battery pack is determined in accordance with the voltage level of the sensed output voltage.

3. The apparatus as claimed in claim 2, wherein the power source charge and discharge unit comprises a power source controller to output a voltage control signal to control a switching operation of the power source unit.

4. The apparatus as claimed in claim 3, wherein the power source controller is to control the switching operation of the power source unit by a pulse width of the voltage control signal.

5. The apparatus as claimed in claim 4, wherein the power source unit changes the voltage level of the charge voltage by the switching operation.

6. The apparatus as claimed in claim 2, wherein the power source unit is configured to receive an input voltage from an adaptor changing an alternating current (AC) voltage into a direct current (DC) voltage.

7. The apparatus as claimed in claim 1, wherein the output voltage from the battery pack is directly proportional to the number of cells in the battery.

8. The apparatus as claimed in claim 1, wherein the voltage sensing unit is to sense the output voltage of the battery pack charged with the predetermined voltage after an initializing period.

9. The apparatus as claimed in claim 1, wherein the first period occurs before the controller determined the number of cells in the battery pack.

10. The apparatus as claimed in claim 1, wherein:

a voltage level of the predetermined voltage is constant for the first period, and

a voltage level of the charge voltage is constant for the second period.

11. A method of charging a battery pack, comprising:

applying a predetermined voltage to the battery pack for a first period using a power source charge and discharge unit;

sensing an output voltage output from the battery pack after applying the predetermined voltage to the battery pack for the first period;

determining a number of cells in the battery pack in accordance with the sensed output voltage; and

supplying a charge voltage to the battery pack using the power source charge and discharge unit, the charge voltage being determined in accordance with number of cells in the battery pack for a second period, wherein

the predetermined voltage is set with a constant voltage regardless of the number of cells in the battery pack for the first period, and the charge voltage is changed according to the number of cells in the battery for the second period.

12. The method as claimed in claim 11, wherein determining the number of cells of the battery pack is in accordance with a voltage level of the output voltage.

13. The method as claimed in claim 11, wherein supplying the charge voltage to the battery pack includes repeating a switching operation on an input voltage such that the input voltage is transmitted or blocked to charge electrical energy and outputting a charge voltage higher than the input voltage.

14. The method as claimed in claim 13, further comprising controlling repeating in accordance with a voltage control signal.

15. The method as claimed in claim 14, wherein controlling is in accordance with a pulse width of the voltage control signal.

16. The method as claimed in claim 13, wherein the input voltage is a direct current (DC) voltage converted from an alternating current (AC) voltage from an external source.

17. The method as claimed in claim 11, wherein sensing the output voltage includes sensing the output voltage of the battery pack charged with the predetermined voltage after an initializing period.

18. The method as claimed in claim 11, wherein applying the predetermined voltage before determining the number of cells.

19. The method as claimed in claim 11, wherein:

a voltage level of the predetermined voltage is constant for the first period, and

a voltage level of the charge voltage is constant for the second period.