Method and Circuitry to Adaptively Charge a Battery/Cell

• US 20110285356A1
• Filed: 05/19/2011
• Published: 11/24/2011
• Est. Priority Date: 05/21/2010
• Status: Active Grant

• Current Assignee: Qnovo, Inc.
• Original Assignee: Qnovo, Inc.
• Inventors: Maluf, Nadim, Ghantous, Dania, Berkowitz, Fred
• Granted Patent: US 8,638,070 B2
• Time in Patent Office: Days
• US Class Current: 320/139
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/007184 in response to battery voltage gradient
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

The present inventions, in one aspect, are directed to techniques and/or circuitry to adaptively charge a battery/cell using data which is representative of a change in terminal voltage of the battery/cell. In another aspect, the present inventions are directed to techniques and/or circuitry to adaptively charge a battery/cell using data which is representative of a partial relaxation time of the battery/cell. In yet another aspect the present inventions are directed to techniques and/or circuitry to adaptively charge a battery/cell using data which is representative of an overpotential or full relaxation time of the battery/cell. In another aspect the present inventions are directed to techniques and/or circuitry to adaptively charge a battery/cell using data which is representative of a state of charge of the battery/cell. In another aspect the present inventions are directed to techniques and/or circuitry to adaptively charge a battery/cell using data which is representative of a state of health of the battery/cell.

Claims

1. A method to adaptively charge a battery, wherein the battery includes at least two terminals, the method comprising:

applying a charge signal to the terminals of the battery, wherein the charge signal includes a plurality of charge packets, wherein each charge packet includes at least one pulse;

measuring a voltage at the terminals of the battery;

determining data which is representative of a relaxation time of the battery, wherein the relaxation time is an amount of time between (i) a time corresponding to (a) an end of the at least one pulse of a charge packet of the charge signal and/or (b) a peak of a change in the voltage at the terminals of the battery due to the at least one pulse of the charge packet and (ii) a time corresponding to when the voltage at the terminals of the battery/cell decays to at least a predetermined voltage; and

adapting one or more characteristics of the charge signal based on or using data which is representative of the relaxation time.

2. The method of claim 1 wherein the predetermined voltage is a voltage which is less than or equal to 10% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the charge packet.

3. The method of claim 1 wherein the predetermined voltage is a voltage which is less than or equal to 5% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the charge packet.

4. The method of claim 1 further including:

determining whether the relaxation time is within a predetermined range and/or greater than a predetermined value; and

wherein adapting one or more characteristics of the charge signal further includes adapting one or more characteristics of the charge signal when the relaxation time exceeds within the predetermined range and/or is greater than the predetermined value.

5. The method of claim 4 wherein the predetermined range and/or the predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

6. The method of claim 1 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the relaxation time includes changing the amount of time between pulses of temporally successive charge packets of the plurality of charge packets.

7. The method of claim 1 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the relaxation time includes changing the amplitude and/or duration of at least one pulse of a charge packet of the plurality of charge packets.

8. The method of claim 1 wherein applying a charge signal to the terminals of the battery, further includes applying a plurality of charge packets, wherein each charge packet includes at least one charge pulse and at least one discharge pulse.

9. The method of claim 8 wherein each charge packet further includes a rest period at the conclusion of a final pulse of each charge packet, and the method further includes:

adapting (i) the amplitudes and/or pulse widths of at least one charge pulse and/or at least one discharge pulse of each charge packet, and (ii) the length of time of the rest period based on data which is representative of the relaxation time.

10. A method to adaptively charge a battery, wherein the battery includes at least two terminals, the method comprising:

applying a charge signal to the terminals of the battery, wherein the charge signal includes a plurality of charge packets, wherein each charge packet includes at least one pulse;

measuring a voltage at the terminals of the battery;

determining data which is representative of a first relaxation time of the battery, wherein the first relaxation time is an amount of time between (i) a time corresponding to (a) an end of the at least one pulse of a first charge packet of the charge signal and/or (b) a peak of a change in the voltage at the terminals of the battery due to the at least one pulse of the first charge packet and (ii) a time corresponding to when the voltage at the terminals of the battery/cell decays to at least a first predetermined voltage;

determining data which is representative of a second relaxation time of the battery, wherein the second relaxation time is an amount of time between (i) a time corresponding to (a) an end of the at least one pulse of a second charge packet of the charge signal and/or (b) a time corresponding to a peak of a change in the voltage at the terminals of the battery due to the at least one pulse of the second charge packet and (ii) a time corresponding to the voltage at the terminals of the battery/cell decays to at least a second predetermined voltage; and

adapting one or more characteristics of the charge signal based on or using data which is representative of the first relaxation time and the second relaxation time.

11. The method of claim 10 wherein the first predetermined voltage is a voltage which is less than or equal to 10% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the first charge packet.

12. The method of claim 10 wherein the first predetermined voltage is a voltage which is less than or equal to 5% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the first charge packet.

13. The method of claim 10 wherein the second predetermined voltage is a voltage which is constant or substantially constant after the second charge packet and while charging signal is not applied to the battery.

14. The method of claim 10 wherein the second predetermined voltage is a voltage which is greater than 50% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the second charge packet.

15. The method of claim 10 wherein the second predetermined voltage is a voltage at which the second relaxation time is capable of being determined based on or using the form, shape and/or rate of decay of the voltage at the terminals of the battery due to the at least one pulse of the second charge packet.

16. The method of claim 10 further including:

determining whether the first relaxation time is within a first predetermined range and/or greater than a first predetermined value; and

wherein adapting one or more characteristics of the charge signal further includes adapting one or more characteristics of the charge signal when the first relaxation time exceeds within the first predetermined range and/or is greater than the first predetermined value.

17. The method of claim 16 wherein the first predetermined range and/or the first predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

18. The method of claim 10 further including:

determining whether the second relaxation time is within a second predetermined range and/or greater than a second predetermined value; and

wherein adapting one or more characteristics of the charge signal further includes adapting one or more characteristics of the charge signal when the second relaxation time exceeds within the second predetermined range and/or is greater than the second predetermined value.

19. The method of claim 18 wherein the second predetermined range and/or the second predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

20. The method of claim 10 wherein determining data which is representative of a second relaxation time of the battery includes determining an overpotential of the battery.

21. The method of claim 20 further including:

determining whether the overpotential of the battery is within a second predetermined range and/or greater than a second predetermined value; and

wherein adapting one or more characteristics of the charge signal further includes adapting one or more characteristics of the charge signal when the overpotential exceeds within the second predetermined range and/or is greater than the second predetermined value.

22. The method of claim 21 wherein the second predetermined range and/or the second predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

23. The method of claim 10 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the first relaxation time includes changing the amount of time between pulses of temporally successive charge packets of the plurality of charge packets.

24. The method of claim 10 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the first relaxation time includes changing the amplitude and/or duration of at least one pulse of a charge packet of the plurality of charge packets.

25. The method of claim 10 wherein applying a charge signal to the terminals of the battery, further includes applying a plurality of charge packets, wherein each charge packet includes at least one charge pulse and at least one discharge pulse.

26. The method of claim 25 wherein each charge packet further includes a rest period at the conclusion of a final pulse of each charge packet, and the method further includes:

adapting, based on data which is representative of the first relaxation time and the second relaxation time, (i) the amplitudes and/or pulse widths of at least one charge pulse and/or at least one discharge pulse of each charge packet, and (ii) the length of time of the rest period based on data which is representative of the first relaxation time and the second relaxation time.

27. The method of claim 25 wherein each charge packet further includes a rest period at the conclusion of a final pulse of each charge packet, and the method further includes:

adapting, based on data which is representative of the second relaxation time, (i) the amplitudes and/or pulse widths of at least one charge pulse and/or at least one discharge pulse of each charge packet, and (ii) the length of time of the rest period.

28. The method of claim 10 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the second relaxation time includes changing a peak current of the charge signal.

29. The method of claim 10 wherein adapting one or more characteristics of the charge signal based on or using data which is representative of the second relaxation time includes changing a duty cycle of one or more pulses within the charge packets.

30. An apparatus to adaptively charge a battery, wherein the battery includes at least two terminals, the apparatus comprising:

charging circuitry, coupled to the battery, to generate a charge signal and apply the charge signal to the terminals of the battery, wherein the charge signal includes a plurality of charge packets, wherein each charge packet includes at least one pulse;

measuring circuitry, coupled to the battery, to measure a voltage at the terminals of the battery;

control circuitry, coupled to the charging circuitry and the measuring circuitry, and configured to (i) receive data which is representative of the voltage at the terminals of the battery from the measuring circuitry and send one or more control signals to the charging circuitry, wherein the control circuitry is configured to;

determine data which is representative of a relaxation time of the battery, wherein the relaxation time is an amount of time for the voltage at the terminals of the battery/cell to decay to a predetermined voltage; and

generate the one or more control signals using data which is representative of a relaxation time to adapt one or more characteristics of the charge signal.

31. The apparatus of claim 30 wherein the predetermined voltage is a voltage which is less than or equal to 10% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the charge packet.

32. The apparatus of claim 30 wherein the control circuitry:

determines whether the relaxation time is within a predetermined range and/or greater than a predetermined value; and

wherein, when the relaxation time exceeds within the predetermined range and/or is greater than the predetermined value, the control circuitry generates one or more additional control signals and provides the one or more additional control signals to the charging circuitry to responsively change one or more characteristics of the charge signal so that the relaxation time of the battery due to subsequent charge packets is within the predetermined range and/or less than the predetermined value.

33. The apparatus of claim 32 wherein the predetermined range and/or the predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

34. An apparatus to adaptively charge a battery, wherein the battery includes at least two terminals, the apparatus comprising:

charging circuitry, coupled to the battery, to generate a charge signal and apply the charge signal to the terminals of the battery, wherein the charge signal includes a plurality of charge packets, wherein each charge packet includes at least one pulse;

measuring circuitry, coupled to the battery, to measure a voltage at the terminals of the battery;

control circuitry, coupled to the charging circuitry and the measuring circuitry, and configured to (i) receive data which is representative of the voltage at the terminals of the battery from the measuring circuitry and send one or more control signals to the charging circuitry, wherein the control circuitry is configured to;

determine data which is representative of a first relaxation time of the battery, wherein the first relaxation time is an amount of time for the voltage at the terminals of the battery/cell to decay, in response to a first charge packet, to a first predetermined voltage;

determine data which is representative of a second relaxation time of the battery, wherein the second relaxation time is an amount of time for the voltage at the terminals of the battery/cell to decay, in response to a second charge packet, to at least a second predetermined voltage, wherein the first relaxation time is substantially less than the second relaxation time; and

generate the one or more control signals using data which is representative of a first relaxation time and the second relaxation time to adapt one or more characteristics of the charge signal.

35. The apparatus of claim 34 wherein the first predetermined voltage is a voltage which is less than or equal to 10% of the peak of the change in the voltage at the terminals of the battery due to the at least one pulse of the first charge packet.

36. The apparatus of claim 34 wherein the second predetermined voltage is a voltage which is constant or substantially constant after the second charge packet and while charging signal is not applied to the battery.

37. The apparatus of claim 34 wherein the second predetermined voltage is a voltage at which the second relaxation time is capable of being determined based on or using the form, shape and/or rate of decay of the voltage at the terminals of the battery due to the at least one pulse of the second charge packet.

38. The apparatus of claim 34 wherein the control circuitry:

determines whether the first relaxation time is within a first predetermined range and/or greater than a first predetermined value; and

wherein, when the first relaxation time exceeds within the first predetermined range and/or is greater than the first predetermined value, the control circuitry generates one or more additional control signals and provides the one or more additional control signals to the charging circuitry to responsively change one or more characteristics of the charge signal so that the first relaxation time of the battery due to subsequent charge packets is within the first predetermined range and/or less than the first predetermined value.

39. The apparatus of claim 38 wherein the first predetermined range and/or the first predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.

40. The apparatus of claim 34 wherein the control circuitry:

determines whether the second relaxation time is within a second predetermined range and/or greater than a second predetermined value; and

wherein, when the second relaxation time exceeds within the second predetermined range and/or is greater than the second predetermined value, the control circuitry generates one or more additional control signals and provides the one or more additional control signals to the charging circuitry to responsively change one or more characteristics of the charge signal so that the second relaxation time of the battery due to subsequent charge packets is within the second predetermined range and/or less than the second predetermined value.

41. The apparatus of claim 40 wherein the second predetermined range and/or the second predetermined value dynamically change during charging of the battery in accordance with changes in a state of charge of the battery and/or a state of health of the battery.