Method and circuitry to adaptively charge a battery/cell

• US 8,975,874 B2
• Filed: 01/23/2014
• Issued: 03/10/2015
• Est. Priority Date: 05/21/2010
• Status: Active Grant

• Current Assignee: Qnovo, Inc.
• Original Assignee: Qnovo, Inc.
• Inventors: Berkowitz, Fred, Maluf, Nadim, Ghantous, Dania
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US14/161,755
• Publication Number:
  US 20140139192A1
• Time in Patent Office: 411 Days
• Field of Search: 320/127, 320/128, 320/129, 320/133, 320/139, 320/141
• US Class Current: 320/141
• 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 and/or 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 at least one pulse;

measuring a voltage at the terminals of the battery, in response to the at least one pulse of the charge signal, including a first voltage;

determining data which is representative of a relaxation time of the battery, wherein the relaxation time is an amount of time corresponding to when the voltage at the terminals of the battery, in response to the at least one pulse, decays to at least the first voltage; and

adapting one or more characteristics of the charge signal based on or using the relaxation time of the battery.

2. The method of claim 1 wherein the relaxation time is an amount of time between (i) a time corresponding to (a) an end of the at least one pulse and/or (b) a peak of a change in the voltage at the terminals of the battery due to the at least one pulse and (ii) a time corresponding to when the voltage at the terminals of the battery, in response to at least one pulse, decays to at least the first voltage.

3. The method of claim 1 wherein the first voltage corresponds to a partial equilibrium voltage of the battery.

4. The method of claim 1 wherein the first voltage corresponds to a full equilibrium voltage of the battery.

5. The method of claim 1 wherein the first voltage, for a given state of charge of the battery, changes in accordance with a state of health of the battery.

6. The method of claim 1 wherein the charge signal includes a plurality of pulses and adapting one or more characteristics of the charge signal includes changing the amount of time between temporally successive pulses of the charge signal.

7. The method of claim 1 wherein the charge signal includes a plurality of pulses and adapting one or more characteristics of the charge signal includes changing the amplitude and/or duration of a plurality of the plurality of pulses.

8. The method of claim 1 wherein the charge signal includes a plurality of charge pulses and a plurality of discharge pulses.

9. 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 pulses including first and second pulses;

measuring voltages at the terminals of the battery including at least one voltage in response to a first pulse of the charge signal and at least one voltage in response to a second pulse of the charge signal;

determining data which is representative of a first relaxation time of the battery, wherein the first relaxation time is an amount of time corresponding to when the voltage at the terminals of the battery decays to at least a first voltage;

determining data which is representative of a second relaxation time of the battery, wherein the second relaxation time is an amount of time corresponding to when the voltage at the terminals of the battery decays to at least a second voltage, wherein the first relaxation time is substantially less than the second relaxation time;

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

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

10. The method of claim 9 wherein the second voltage is a voltage which is constant or substantially constant after the second pulse and while the charge signal is not applied to the battery.

11. The method of claim 9 wherein the second voltage is a voltage at which the second relaxation time is 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 second pulse.

12. The method of claim 9 wherein the first voltage corresponds to a partial equilibrium voltage of the battery and the second voltage corresponds to a full equilibrium voltage of the battery.

13. The method of claim 9 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 an amount of time between successive pulses of the charge signal.

14. The method of claim 9 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 a plurality of pulses of the plurality of pulses.

15. The method of claim 9 wherein:

the plurality of pulses includes a plurality of charge pulses and a plurality discharge pulses, and

adapting one or more characteristics of the charge signal based on or using the data which is representative of the first relaxation time includes adjusting (i) the amplitudes and/or pulse widths of a plurality of the charge pulses and/or a plurality of the discharge pulses, and/or (ii) the length of time between charge pulses and/or discharge pulses.

16. The method of claim 9 wherein adapting one or more characteristics of the charge signal based on or using the data which is representative of the second relaxation time includes changing a peak current of the charge signal.

17. The method of claim 9 wherein adapting one or more characteristics of the charge signal includes changing a duty cycle of the pulses of the charge signal.

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

charging circuitry, coupled to the battery, to generate a signal and apply the signal to the terminals of the battery, wherein the signal includes a first pulse;

measuring circuitry, coupled to the battery, to measure a voltage at the terminals of the battery in response to the first pulse of the signal; and

control circuitry, coupled to the charging circuitry and the measuring circuitry, and configured to (i) receive data which is representative of the measured voltage and output 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 to decay to a first voltage in response to the first pulse of the signal, and

generate the one or more control signals based on or using the data representative of the relaxation time of the battery.

19. The apparatus of claim 18 wherein the first voltage, for a given state of charge of the battery, changes in accordance with a state of health of the battery.

20. The apparatus of claim 18 wherein the signal includes a plurality of pulses and wherein, in response to the one or more control signals, the charging circuitry changes an amplitude and/or a duration of a plurality of pulses of the plurality of pulses.

21. The apparatus of claim 18 wherein the signal includes a plurality of pulses and wherein the plurality of pulses includes a plurality of charge pulses and a plurality of discharge pulses.

22. The apparatus of claim 21 wherein, in response to the one or more control signals, the charging circuitry changes an amplitude and/or duration of a plurality of the charge pulses and/or discharge pulses.

23. The apparatus of claim 18 wherein the first voltage correlates to a partial equilibrium voltage of the battery.

24. The apparatus of claim 18 wherein the first voltage correlates to a full equilibrium voltage of the battery.

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

charging circuitry, coupled to the battery, to generate a signal and apply the signal to the terminals of the battery, wherein the signal includes a plurality of pulses;

measuring circuitry, coupled to the battery, to measure a voltage at the terminals of the battery in response to at least first and second pulses of the plurality of pulses; and

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 output one or more control signals to the charging circuitry to change one or more characteristics of the signal, 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 to decay, in response to a first pulse, to a first 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 to decay, in response to a second pulse, to at least a second voltage, wherein the second relaxation time is substantially greater than the first relaxation time, and

generate the one or more control signals based on or using data which is representative of the first relaxation time and/or data which is representative of the second relaxation time.

26. The apparatus of claim 25 wherein the second voltage is a voltage at which the second relaxation time is 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 second pulse.

27. The apparatus of claim 25 wherein the first voltage and second voltage, for a given state of charge of the battery, change in accordance with a state of health of the battery.

28. The apparatus of claim 25 wherein the first voltage correlates to a partial equilibrium voltage of the battery and the second voltage correlates to a full equilibrium voltage of the battery.

29. The apparatus of claim 25 wherein the control circuitry adapts one or more characteristics of the charge signal based on or using data which is representative of the first relaxation time and/or the second relaxation time.