Battery management system

• US 8,022,669 B2
• Filed: 06/30/2009
• Issued: 09/20/2011
• Est. Priority Date: 01/06/2009
• Status: Active Grant

• Current Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: Li, Guoxing
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US12/495,495
• Publication Number:
  US 20100173180A1
• Time in Patent Office: 812 Days
• Field of Search: 320/103, 320/107, 320/114, 320/116, 320/117, 320/120, 320/122
• US Class Current: 320/122
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 3/0092 with use of redundant elements for safety purposes
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A battery management system can include a battery having a plurality of cells, a plurality of devices coupled to the battery, and a control unit coupled to a first device of the devices. The devices can assess the statuses of the cells. The control unit can communicate with a destination device of the devices via a default path and can communicate with the destination device via a backup path if an undesirable condition occurs in the default path.

Claims

1. A battery management system, comprising:

a battery having a plurality of cells;

a plurality of devices coupled to said battery and operable for assessing the statuses of said cells; and

a control unit coupled to a first device of said devices and operable for communicating with a destination device of said devices via a default path and for communicating with said destination device via a backup path if an undesirable condition occurs in said default path.

2. The system of claim 1, wherein said undesirable condition comprises a disconnect in said default path.

3. The system of claim 1, wherein said control unit is further coupled to a second device of said devices.

4. The system of claim 3, wherein said default signal path comprises a first plurality of said devices and said backup signal path comprises a second plurality of said devices, wherein said first plurality of said devices and said second plurality of said devices are different.

5. The system of claim 4, wherein said devices are powered by said cells and share a plurality of common voltage levels provided by said cells.

6. The system of claim 5, wherein said first device comprises a device powered by a cell that has the lowest voltage level among said cells.

7. The system of claim 5, wherein said second device comprises a device powered by a cell that has the highest voltage level among said cells.

8. A battery management system, comprising:

a battery having a plurality of cells;

a plurality of devices coupled to said battery and operable for assessing the statuses of said cells, wherein each of said devices comprises;

a monitoring block operable for outputting monitoring signals that indicate a status of a respective cell; and

a bus block coupled to said monitoring block operable for transmitting said monitoring signals, wherein said bus block comprises an internal signal path inside said bus block, wherein an external signal path outside said devices is coupled between said devices and is operable for transmitting said monitoring signals between said devices; and

a control unit coupled to a first device of said devices and operable for communicating with a destination device of said devices via a default path and for communicating with said destination device via a backup path if an undesirable condition occurs in said default path.

9. The system of claim 8, wherein said undesirable condition comprises a disconnect in said default path.

10. The system of claim 8, wherein said internal signal path comprises an internal default signal path and said external signal path comprises an external default signal path.

11. The system of claim 10, wherein said default path comprises a path via said control unit, an internal default signal path in said first device, a first plurality of internal default signal paths inside a first plurality of said devices and a first plurality of external default signal paths between said first device and said destination device.

12. The system of claim 11, wherein said internal signal path further comprises an internal backup signal path.

13. The system of claim 12, wherein said backup path comprises a path that is different from said default path in that, if said undesirable condition occurs in an internal default signal path in said first device, then said internal default signal path in said first device is replaced by an internal backup signal path that is located in said first device.

14. The system of claim 11, wherein said external signal path further comprises an external backup signal path.

15. The system of claim 14, wherein said backup path comprises a path that is different from said default path in that, if said undesirable condition occurs in an external default signal path in said first plurality of external default signal paths between said first device and said destination device, then said external default signal path is replaced by an external backup signal path that is located between said first device and said destination device.

16. The system of claim 11, wherein said control unit is further coupled to a second device of said devices, and wherein said backup path comprises a path via said control unit, an internal default signal path in said second device, a second plurality of internal default signal paths inside a second plurality of said devices and a second plurality of external default signal paths between said second device and said destination device.

17. The system of claim 16, wherein said second device comprises a device powered by a cell that has the highest voltage level among said cells.

18. The system of claim 8, wherein said devices are powered by said cells and share a plurality of common voltage levels provided by said cells.

19. The system of claim 18, wherein said first device comprises a device powered by a cell that has the lowest voltage level among said cells.

20. A method for enabling communication in a battery management system, comprising:

determining if an undesirable condition occurs in a default path operable for enabling said communication between a control unit and a destination front end device; and

enabling said communication via a backup path if said undesirable condition is detected and otherwise enabling said communication via said default path.