Systems and methods for harmonic-based battery charging
Aspects of the present disclosure involve charging or discharging an electrochemical device such as a battery. The system generates a waveform, such as a charge signal, to tune harmonic attributes of the waveform based on the impedance of the battery to a harmonic or harmonics of the waveform. The system may enhance (e.g., add or increase magnitude) or suppress (e.g., delete or reduce magnitude) harmonics of the waveform. Such a harmonically tuned waveform may optimize energy transfer to or from the battery to achieve various possible goals including charging speed, enhancing battery charge capacity and/or enhancing battery cycle life.
1. A method of managing charging an electrochemical device comprising:
transforming, using a processor, a waveform from the time domain to a frequency domain to identify a plurality of harmonic components of the waveform;
altering a harmonic component of the plurality of harmonic components of the waveform transformed to the frequency domain;
transforming the altered waveform to the time domain to generate a harmonically tuned charging waveform including the altered harmonic component; and
applying the harmonically tuned charging waveform to the electrochemical device to charge the electrochemical device.
2. The method of claim 1 wherein transforming the waveform from the time domain to the frequency domain comprises a transformation from a time domain representation of the waveform to a frequency domain representation of the waveform, the frequency domain representation of the waveform further comprising a magnitude associated with the harmonic component.
3. The method of claim 2 wherein altering the harmonic component comprises altering the magnitude associated with the harmonic component.
4. The method of claim 1 further comprising identifying an impedance at the electrochemical device of the harmonic component and wherein the altering the harmonic component of the plurality of harmonic components is based on the identified impedance of the harmonic component.
5. The method of claim 4 wherein the harmonically tuned charging waveform is used to charge the electrochemical device with less impedance as compared to the waveform.
6. The method of claim 1 wherein the waveform is a portion of the waveform within a time boundary.
7. The method of claim 6 , further comprising:
establishing an upper time boundary and a lower time boundary of the time boundary defining a first portion of the waveform; and
obtaining transformed frequency domain data of the portion of the waveform.
8. The method of claim 7 , further comprising:
establishing a second upper time boundary and a second lower time boundary of a second portion of the waveform, the second portion of the waveform occurring after the first portion of the waveform; and
obtaining transformed frequency domain data of the second portion of the waveform.
9. The method of claim 8 , further comprising:
combining the data of the first portion of the waveform and the data of the second portion of the waveform on a timeline associated with the waveform.
10. The method of claim 1 wherein the harmonic of the plurality of harmonics of the waveform has a high impedance of the electrochemical device and altering the harmonic component comprises suppressing the harmonic component.
11. The method of claim 1 wherein the harmonic of the plurality of harmonics of the waveform has a low impedance of the electrochemical device and altering the harmonic component comprises enhancing the harmonic component.
12. The method of claim 2 wherein transforming the waveform from a time domain to a frequency domain comprises utilizing a transform with a basis function based on the stationary and periodic nature of the waveform.
13. A method of charging an electrochemical device comprising:
applying, to a waveform associated with an electrochemical device, a wavelet frequency transform to transform the waveform to the frequency domain including a harmonic component of the waveform;
identifying an effect of the harmonic component;
altering, based on the identified effect, the harmonic component of the waveform;
transforming the waveform including the altered harmonic component to the time domain to generate a harmonically tuned charging waveform including the altered harmonic component; and
applying the harmonically tuned charging waveform to the electrochemical device to charge the electrochemical device.
14. The method of claim 13 wherein the waveform is a charge signal for energy transfer to the electrochemical device.
15. The method of claim 13 wherein the effect of the identified component is impedance.
16. The method of claim 13 wherein altering the harmonic component comprises enhancing the harmonic component or suppressing the harmonic component.
17. The method of claim 13 , further comprising:
identifying, based on the frequency domain of the waveform, a characteristic of the electrochemical device.
18. The method of claim 17 wherein the characteristic of the electrochemical device is associated with a charge rate of the electrochemical device.