Protection circuit for battery pack

• US 8,854,007 B2
• Filed: 12/03/2010
• Issued: 10/07/2014
• Est. Priority Date: 12/29/2009
• Status: Expired due to Fees

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Kim, Jin-Wan, Segawa, Susumu, Hwang, Eui-Jeong, Sim, Se-Sub, Yang, Jong-Woon, Yun, Han-Seok, Kim, Beom-Gyu
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): PELTON, NATHANIEL R
• Application Number:
  US12/960,395
• Publication Number:
  US 20110156654A1
• Time in Patent Office: 1,404 Days
• Field of Search: 320/134, 320/162, 320/145
• US Class Current: 320/134
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence

Abstract

A protection circuit of a battery pack capable of detecting the error of a charging device from the battery pack. The protection circuit of the battery pack having a battery cell charged by a charging device, the protection circuit including a charge switch coupled to a high current path (HCP), the charge switch disposed between the battery cell and the charging device charging the battery cell and a controller sensing a voltage or a current of the charging device during a charge stop period stopping a charging of the battery cell and determining whether an error of the charging device occurs according to the voltage or the current of the charging device.

Claims

1. A protection circuit of a battery pack having a battery cell charged by a charging device, the protection circuit comprising:

a charge switch coupled to a high current path (HCP), the charge switch disposed between the battery cell and the charging device configured to charge the battery cell;

a detecting unit coupled to the HCP at a node between the charge switch and the charging device and configured to detect a voltage or a current on the HCP of the charging device;

a controller configured to sense the voltage or the current of the charging device through the detecting unit during a charge stop period stopping a charging of the battery cell and to determine whether or not an error of the charging device occurs according to the voltage or the current of the charging device, and

a blocking unit configured to block coupling between the charging device and the battery cell when the error occurs, wherein the blocking unit comprises;

a fuse coupled to the HCP in series;

a heater having a first terminal coupled to an end of the fuse; and

a control switch coupled between a second terminal of the heater and a ground, wherein a gate terminal of the control switch is coupled to the controller.

2. The protection circuit as claimed in claim 1, wherein the charge stop period comprises a period in which the charge switch is turned off in at least one of periods between adjacent pulses of a pulse charging of the battery cell.

3. The protection circuit as claimed in claim 2, wherein the controller is configured to compare the voltage of the charging device with a reference voltage corresponding to a charge voltage characteristic of the battery cell and to determine whether the error occurs according to a comparison result.

4. The protection circuit as claimed in claim 1, wherein the charge stop period comprises a period in which the charge switch is turned off when the battery cell is charged by a constant current-constant voltage (CC-CV) method.

5. The protection circuit as claimed in claim 4, wherein the controller is configured to turn off the charge switch.

6. The protection circuit as claimed in claim 4, wherein the controller is configured to compare the voltage or the current of the charging device with a reference voltage or a reference current corresponding to a CC-CV characteristic and to determine whether the error occurs according to a comparison result.

7. The protection circuit as claimed in claim 1, wherein the controller is configured to output information on the error to the charging device.

8. The protection circuit as claimed in claim 7, further comprising an outputting unit configured to display information on the error by a light, a sound, or a combination of the light and the sound.

9. The protection circuit as claimed in claim 7, wherein the information on the error is transmitted to the charging device.

10. The protection circuit as claimed in claim 1, further comprising a discharge switch coupled to the HCP and disposed in series between the battery cell and the charging device.

11. The protection circuit as claimed in claim 1, wherein the controller comprises an analog front end (AFE) integrated circuit (IC) and a microcontroller.

12. The protection circuit as claimed in claim 1, further comprising an external terminal, comprising:

a first power source terminal coupled to the HCP;

a second power source terminal coupled to the HCP; and

at least one signal terminal configured to transmit information on the error to the charging device.

13. The protection circuit as claimed in claim 1, wherein the battery cell comprises at least one of a chargeable and a dischargeable secondary battery.

14. The protection circuit as claimed in claim 1, wherein the charging device is an electronic apparatus including a battery charger or an adaptor.

15. The protection circuit as claimed in claim 11, further comprising a system management bus (SMBUS) having a clock line and a data line connecting the microcontroller to an external system.