Battery management system with integration of voltage sensor and charge equalizer

• US 8,253,378 B2
• Filed: 10/16/2008
• Issued: 08/28/2012
• Est. Priority Date: 10/16/2007
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology, SK On Company Limited (SK Innovation Company Limited)
• Original Assignee: SK Innovation Company Limited
• Inventors: Lee, Joong Hui, Jang, Soo Yeup, Oh, Jeon Keun, Moon, Gun Woo, Park, Hong Sun, Kim, Chol Ho
• Primary Examiner(s): DIAO, M BAYE
• Application Number:
  US12/738,346
• Publication Number:
  US 20100231166A1
• Time in Patent Office: 1,412 Days
• Field of Search: 320/118, 320/116, 320/119
• US Class Current: 320/118
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: H02J 7/0018 using separate charge circuits
• CPC Class Codes: H02J 7/0019 using switched or multiplexed charge circuits
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery management system according to the present invention comprises a battery module consisted of a plurality of batteries connected in series; a switch module connected in parallel to the battery module; a voltage sensor measuring a voltage of each battery composing the battery module; a charge equalizer causing each battery composing the battery module to be charged, discharged or charged/discharged; and a microprocessor controlling the switch module to determine whether to charge or discharge each battery composing the battery module according to the voltage values measured by the voltage sensor and; wherein the voltage sensor and the charge equalizer are connected in parallel to each battery composing the battery module by the switch module.

Claims

1. A battery management system, comprising:

a battery module including a plurality of batteries connected in series;

a switch module connected in parallel to the battery module;

a voltage sensor which measures a voltage of each battery included in the battery module;

a charge equalizer causing each battery included in the battery module to be charged, discharged or charged/discharged; and

a microprocessor controlling the switch module to determine whether to charge or discharge each battery included in the battery module according to the voltage values measured by the voltage sensor,

wherein the voltage sensor and the charge equalizer are connected in parallel to each battery included in the battery module by the same switch module.

2. The battery management system according to claim 1, wherein the switch module is controlled by the microprocessor and one battery included in the battery module is connected in parallel to the voltage sensor in a time-division manner.

3. The battery management system according to claim 2, wherein the switch module is controlled by the microprocessor and one battery included in the battery module is connected in parallel to the charge equalizer in a time-division manner.

4. The battery management system according to claim 1, wherein the voltage sensor comprises a capacitor and an A/D converter.

5. The battery management system according to claim 3, wherein the switch module comprises a device capable of current bidirectional movement including a Field Effect Transistor (FET), Bipolar Junction Transistor (BJT) or a relay.

6. The battery management system according to claim 1, wherein the charge equalizer is a discharging circuit, charging circuit or charging/discharging circuit comprising an active element selected from a group consisting of a Field Effect Transistor, a Bipolar Junction Transistor, a relay and diode;

and a passive element selected from a group consisting of an inductor, a transformer and a capacitor.

7. The battery management system according to claim 6, wherein the charge equalizer comprises a charge-type DC/DC converter, a discharge-type DC/DC converter, or a combination thereof.

8. The battery management system according to claim 7, wherein the charge-type DC/DC converter has a total potential of the battery module or an external energy storage apparatus as an input.

9. The battery management system according to claim 7, wherein the discharge-type DC/DC converter has a total potential of the battery module or an external energy storage apparatus as an output.

10. The battery management system according to claim 1, wherein the charge equalizer is a discharging circuit comprising a resistor.

11. The battery management system according to claim 1, wherein the battery management system includes at least two battery modules;

and the switch module, the voltage sensor, and the charge equalizer are provided for each module.

12. A battery management method for a battery management system comprising:

a battery module including a plurality of batteries connected in series;

a switch module connected in parallel to the battery module;

a voltage sensor measuring a voltage of each battery included in the battery module;

a charge equalizer causing each battery to be charged, discharged or charged/discharged; and

a microprocessor controlling the switch module, the method comprising the steps of;

(a) inputting a voltage value of each battery to the microprocessor by connecting the battery to the voltage sensor using the switch module for a prescribed time, for each battery included in the battery module; and

(b) connecting the charge equalizer to a single battery which is selected to be charged or discharged based on the voltage values inputted to the microprocessor using the switch module to charge or discharge the single battery.

13. The battery management method according to claim 12, wherein step (b) further comprises the step of selecting whether the charge equalizer performs charging or discharging via the microprocessor if the charge equalizer is a charge/discharge-type charge equalizer.

14. The battery management method according to claim 12, wherein the switch module is controlled in a time-division manner so that a voltage value of each battery included in the battery module is input to the microprocessor in step (a).

15. The battery management method according to claim 12, wherein the switch module is controlled in a time-division manner so that the individual battery included in the battery module may be charged or discharged in step (b).

16. The battery management method according to claim 12, wherein the input of the charge equalizer is connected to a total potential of the batteries connected in series or an external energy storage apparatus when charging the individual battery using the charge equalizer and the output of the charge equalizer is connected to a total potential of the batteries connected in series or an external energy storage apparatus when discharging the individual battery.

17. The battery management method according to claim 12, wherein the battery management system is comprised of at least two battery modules, and wherein the switch module, the voltage sensor and the charge equalizer are provided for each battery module, so that step (a) and (b) are processed independently for each battery module.

18. A non-transitory computer-readable recording media that stores a program for executing the battery management method according to claim 12.