Method and apparatus for multiple battery cell management

• US 20050127874A1
• Filed: 12/12/2003
• Published: 06/16/2005
• Est. Priority Date: 12/12/2003
• Status: Abandoned Application

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Griffin, Keith, Yi, Woo-chul, Lim, Myoungho, Flaherty, Mark J.
• Application Number:
  US10/735,010
• Publication Number:
  US 20050127874A1
• Time in Patent Office: Days
• US Class Current: 320/128
• 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

Embodiments of the present invention are directed to a method and apparatus for multiple battery cell management. In one embodiment, a solid state relay is used instead of a mechanical relay in a BMS. The SSR is smaller and faster than a mechanical relay, enabling smaller BMSs that more efficiently and safely manage battery cell charge. In another embodiment, a plurality of battery cells are connected to two rails, using four SSRs to control access to the battery cells. In one embodiment, a plurality of battery cells are grouped together and controlled as one module of a multi-module BMS. In one embodiment, each module has 10 battery cells in series. In one embodiment, the BMS controls 4 modules. In one embodiment, each module is controlled by control signals passing through logical gates. In another embodiment, each module is controlled by control signals passing through a programmed circuit.

Claims

1. A method for managing a battery system comprising:

using a solid state relay as a switch during an operation of said battery system.

2. The method of claim 1 wherein said solid state relay is an optically isolated field-effect transistor.

3. The method of claim 1 wherein said operation is a read and wherein said switch completes a circuit comprising:

a side of a battery cell; and

an input of a voltage differentiator.

4. The method of claim 1 wherein said operation is a buck and wherein said switch completes a circuit comprising:

a first side of a battery cell;

a resistor; and

a second side of a battery cell.

5. The method of claim 1 wherein said operation is a boost and wherein said switch completes a circuit comprising:

a side of a battery cell; and

a voltage source.

6. The method of claim 1 further comprising:

controlling said battery system using a logic circuit.

7. The method of claim 1 further comprising:

controlling said battery system using an EPROM.

8. The method of claim 1 further comprising:

controlling said battery system using a programmable logic array.

9. The method of claim 1 wherein a control circuit that controls said switch is protected from a higher voltage circuit wherein said switch-is a component of said higher voltage circuit.

10. A method of managing a battery system comprising:

providing a first rail; and

providing a second rail;

11. The method of claim 10 further comprising:

providing a first switch connected to a high line of said first rail;

providing a second switch connected to a low line of said first rail;

providing a third switch connected to a high line of said second rail; and

providing a fourth switch connected to a low line of said second rail.

12. The method of claim 10 further comprising:

partitioning a first battery cell into a first battery group;

partitioning a second battery cell into a second battery group wherein said second battery cell is in series with said first battery cell and wherein a first side of said first battery cell is electrically connected to a first side of said second battery cell; and

accessing said first side of said first battery cell and a second side of said first battery cell using said first rail.

13. The method of claim 12 further comprising:

accessing said first side of said second battery cell and a second side of said second battery cell using said second rail.

14. A method of managing a battery system comprising:

partitioning a plurality of battery cells into a plurality of battery cell groups;

controlling battery management functions of a first battery cell group using a battery management control module.

15. The method of claim 14 wherein said battery management control module is controlled by a 16-bit control input.

16. The method of claim 14 wherein said battery management control module is controlled by a 8-bit control input.

17. The method of claim 14 wherein four battery management control modules are used to control battery management functions of four battery cell groups.

18. The method of claim 14 wherein a first battery cell group has ten battery cells.

19. A battery management system comprising:

a solid state relay configured to function as a switch during an operation of said battery management system.

20. The battery management system of claim 19 wherein said solid state relay is an optically isolated field-effect transistor.

21. The battery management system of claim 19 wherein said operation is a read and wherein said solid state relay completes a circuit comprising:

a side of a battery cell; and

an input of a voltage differentiator.

22. The battery management system of claim 19 wherein said operation is a buck and wherein said solid state relay completes a circuit comprising:

a first side of a battery cell;

a resistor; and

a second side of a battery cell.

23. The battery management system of claim 19 wherein said operation is a boost and wherein said solid state relay completes a circuit comprising:

a side of a battery cell; and

a voltage source.

24. The battery management system of claim 19 further comprising:

a logic circuit configured to control said battery management system.

25. The battery management system of claim 19 further comprising:

an EPROM configured to control said battery management system.

26. The battery management system of claim 19 further comprising:

a programmable logic array configured to control said battery management system.

27. The battery management system of claim 19 further comprising:

a control circuit configured to control said solid state relay wherein said control circuit is protected from a higher voltage circuit and wherein said solid state relay is a component of said higher voltage circuit.

28. A battery management system comprising:

a first rail; and

a second rail;

29. The battery management system of claim 28 further comprising:

a first switch connected to a high line of said first rail;

a second switch connected to a low line of said first rail;

a third switch connected to a high line of said second rail; and

a fourth switch connected to a low line of said second rail.

30. The battery management system of claim 28 further comprising:

a partitioning unit configured to partition a first battery cell into a first battery group wherein said partitioning unit is further configured to partition a second battery cell into a second battery group wherein said second battery cell is in series with said first battery cell and wherein a first side of said first battery cell is electrically connected to a first side of said second battery cell; and

a control unit configured to access said first side of said first battery cell and a second side of said first battery cell using said first rail.

31. The battery management system of claim 30 further comprising:

a second control configured to access said first side of said second battery cell and a second side of said second battery cell using said second rail.

32. A battery management system comprising:

a partitioning unit configured to partition a plurality of battery cells into a plurality of battery cell groups;

a control unit configured to control battery management functions of a first battery cell group using a battery management control module.

33. The battery management system of claim 32 wherein said battery management control module is controlled by a 16-bit control input.

34. The battery management system of claim 32 wherein said battery management control module is controlled by a 8-bit control input.

35. The battery management system of claim 32 wherein four battery management control modules are used to control battery management functions of four battery cell groups.

36. The battery management system of claim 32 wherein a first battery cell group has ten battery cells.