BATTERY MANAGEMENT SYSTEM AND BATTERY MANAGEMENT METHOD

• US 20100134070A1
• Filed: 11/27/2009
• Published: 06/03/2010
• Est. Priority Date: 12/01/2008
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: YUN, Han-Seok, MURAKAMI, Yusai
• Granted Patent: US 8,810,201 B2
• Time in Patent Office: Days
• US Class Current: 320/118
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/19 Switching between serial connection and parallel connection of battery modules
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: B60L 58/33 by cooling
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A battery management system and a driving method thereof, to set a discharge completion voltage using the cell voltages of cells of a battery, and to balance the cell voltages according to the set discharge completion voltage.

Claims

1. A battery management system, comprising:

cells having cell voltages;

a cell balancing unit that performs a control operation to balance the cell voltages; and

a micro-control unit (MCU) that measures the cell voltages, to detect whether one or more of the cells are unbalanced, and controls the cell balancing unit to perform the control operation, until the cell voltages of the one or more unbalanced cells reach a discharge completion voltage.

2. The battery management system of claim 1, wherein the discharge completion voltage is less than the highest cell voltage and is greater than the lowest cell voltage.

3. The battery management system of claim 1, wherein the discharge completion voltage is obtained by adding an error voltage to the lowest cell voltage.

4. The battery management system of claim 1, wherein the discharge completion voltage is obtained by adding a capacity deviation target voltage to the lowest cell voltage.

15. The battery management system of claim 1, wherein the discharge completion voltage is an average of some or all of the cell voltages.

5. A battery management system, comprising:

cells having cell voltages;

a cell balancing unit that performs a control operation to balance the cell voltages; and

a micro-control unit (MCU) that measures the cell voltages, to detect whether one or more of the cells are unbalanced, and controls the cell balancing unit, to perform a control operation until the cell voltages of the one or more unbalanced cells reach an average of at least two of the cell voltages.

6. The battery management system of claim 5, wherein the MCU controls the cell balancing unit to discharge the one of more unbalanced cells, until the cell voltages of the one or more unbalanced cells reach an average of all the cell voltages.

7. The battery management system of claim 5, wherein the cell balancing unit discharges the one or more unbalanced cells, until the cell voltages of the one or more unbalanced cells reach an average of the highest and lowest cell voltages.

8. A battery management method, comprising:

measuring the voltages of cells;

comparing the measured cell voltages to a discharge completion voltage, to determine whether one or more of the cells are unbalanced; and

discharging the one or more unbalanced cells to the discharge completion voltage,

wherein the discharge completion voltage is higher than the lowest cell voltage.

9. The battery management method of claim 8, wherein the discharge completion voltage is less than the highest cell voltage and is greater than the lowest cell voltage.

10. The battery management method of claim 8, wherein the discharge completion voltage is obtained by adding an error voltage to the lowest cell voltage.

11. The battery management method of claim 8, wherein the discharge completion voltage is obtained by adding a capacity deviation target voltage to the lowest cell voltage.

16. The battery management method of claim 8, wherein the discharge completion voltage is an average of some or all of the cell voltages.

12. A battery management method, comprising:

measuring the cell voltages cells;

comparing the measured cell voltages to a discharge completion voltage, to determine whether one or more of the cells are unbalanced; and

discharging the one or more unbalanced cells to the discharge completion voltage,

wherein the discharge completion voltage is an average of at least two of the cell voltages.

13. The battery management method of claim 12, wherein the discharge completion voltage is an average of all of the cell voltages.

14. The battery management method of claim 12, wherein the discharge completion voltage is an average of the highest cell voltage and the lowest cell voltage.