Modular control electronics for batteries

• US 6,043,629 A
• Filed: 11/03/1998
• Issued: 03/28/2000
• Est. Priority Date: 11/03/1998
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Inventors: Ashley, Christopher R., Becker-Irvin, Craig H.
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/185,239
• Time in Patent Office: 511 Days
• Field of Search: 320/127, 320/128, 320/132, 320/136, 320/135, 320/118, 320/119, 363/60, 363/65, 363/71, 363/59, 361/84, 361/18, 361/82, 361/92
• US Class Current: 320/119
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A power system includes at least two battery cell modules. Each battery cell module has a lithium-ion battery cell, and a battery cell controller operably connected to the lithium-ion battery to control the charging and discharging of the lithium-ion battery cell. A central charge/discharge controller is operably connected to each of the battery cell controllers, allowing the charging and discharging of each lithium-ion battery cell to be individually controlled.

Claims

1. A power system, comprising:

at least two battery cell modules, each battery cell module comprising;

a battery cell; and

a battery cell controller operably connected to the battery cell to control the charging and discharging of the battery cell; and

a central charge/discharge controller operably connected to each of the battery cell controllers of the at least two battery cell modules, wherein the central charge/discharge controller is operable to individually command the charging current and the discharging current of the battery cell modules.

2. The power system of claim 1, wherein each of the battery cell controllers comprises at least one dc-to-dc power converter.

3. The power system of claim 2, wherein the at least one dc-to-dc converter comprises one dc-to-dc bidirectional power converter.

4. The power system of claim 2, wherein the at least one dc-to-dc converter comprises two dc-to-dc unidirectional power converters.

5. The power system of claim 1, wherein each module has a power output, and wherein the power outputs of the at least two battery cell modules are electrically connected in parallel.

6. The power system of claim 1, wherein each module has a negative-polarity power output and a positive-polarity power output, and wherein the negative-polarity power output is electrically connected to a system ground.

7. The power system of claim 1, wherein the power system further includes

a power bus to which each of the battery cell controllers is operably connected;

a power source controllably connected to the power bus; and

a power-consuming device controllably connected to the power bus.

8. The power system of claim 1, wherein each battery cell is a lithium-ion battery cell.

17. The power system of claim 1, wherein the central charge/discharge controller is operable to

individually charge each battery cell through its respective battery cell controller at a controlled current until a preselected voltage is reached across the battery cell, and thereafter maintain the preselected voltage and continue to charge the battery cell with a decreasing current, and thereafter

individually discharge each battery cell through its respective battery cell controller at a controlled output voltage until a preselected cell voltage is reached across the cell, and thereafter maintain the preselected cell voltage and continue to discharge the battery cell with a decreasing current.

9. A method for supplying power, comprising the steps of providing at least two battery cell modules, each battery cell module comprising:

a lithium-ion battery cell; and

a battery cell controller operably connected to the lithium-ion battery cell to control the charging and discharging of the lithium-ion battery cell;

providing a central charge/discharge controller operably connected to each of the battery cell controllers of the at least two battery cell modules;

individually charging each battery cell through its respective battery cell controller at a controlled current until a preselected voltage is reached across the battery cell, and thereafter maintaining the preselected voltage and continuing to charge the battery cell with a decreasing current; and

thereafter

individually discharging each battery cell through its respective battery cell controller at a controlled output voltage until a preselected cell voltage is reached across the cell, and thereafter maintaining the preselected cell voltage and continuing to discharge the battery cell with a decreasing current.

10. The method of claim 9, wherein each of the battery cell controllers comprises

at least one dc-to-dc power converter.

11. The method of claim 10, wherein the at least one dc-to-dc converter comprises one dc-to-dc bidirectional power converter.

12. The method of claim 10, wherein the at least one dc-to-dc converter comprises two dc-to-dc unidirectional power converters.

13. The method of claim 9, wherein each module has a power output, and wherein the power outputs of the at least two battery cell modules are electrically connected in parallel.

14. The method of claim 9, wherein each module has a negative-polarity power output and a positive-polarity power output, and wherein, the negative-polarity power output is electrically connected to a system ground.

15. The method of claim 9, wherein the power system further includes

a power bus to which each of the battery cell controllers is operably connected;

a power source controllably connected to the power bus; and

a power-consuming device controllably connected to the power bus.

16. The method of claim 9, wherein the step of discharging discontinuing the discharging of one of the battery cells while continuing the discharging of the remaining battery cells.

18. A power system, comprising:

at least two battery cell modules, each battery cell module comprising;

a battery cell; and

a battery cell controller operably connected to the battery cell to control the charging and discharging of the battery cell, wherein each of the battery cell controllers comprises at least one dc-to-dc power converter including a transformer isolation buck converter; and

a central charge/discharge controller operably connected to each of the battery cell controllers of the at least two battery cell modules.

19. The power system of claim 18, wherein the at least one dc-to-dc converter comprises one dc-to-dc bidirectional power converter.

20. The power system of claim 18, wherein the at least one dc-to-dc converter comprises two dc-to-dc unidirectional power converters.

21. The power system of claim 18, wherein the central charge/discharge controller is operable to individually control the charging and the discharging of each battery.

22. A power system, comprising:

at least two battery cell modules, each battery cell module comprising;

a battery cell; and

a battery cell controller operably connected to the battery cell to control the charging and discharging of the battery cell; and

a central charge/discharge controller operably connected to each of the battery cell controllers of the at least two battery cell modules, wherein the central charge/discharge controller is operable to protect the battery cell modules against overcharging and overdischarging.