Systems and methods for electrochemical device charging and discharging
Systems and methods that charge a battery using a signal with at least one harmonically tuned aspect based on impedance of the battery with a frequency or harmonic component. The system may further involve a power converter that may act in concert with charging to power a load. In some instances, an output signal is generated that is interleaved with the charge signal. Further, the output signal may be tuned based on output impedance to the discharge signal.
1. A charging system comprising:
a charge signal shaping circuit comprising a first switch configured to receive a pulse width modulated (PWM) control signal and operably coupled with an inductor to provide a sequence of pulses to the inductor, the sequence of pulses responsive to the PWM signal;
a controller in operable communication with the charge signal shaping circuit to control the PWM control signal, the controller configured to generate a charge current waveform with a shaped leading edge defining an increasing charge current followed by a constant current body portion by controlling a duty cycle of the sequence of pulses to the inductor, the controlled sequence of pulses producing the shaped leading edge of the charge current waveform from the inductor, and then providing a constant duty cycle of the sequence of pulses to provide the constant current body portion of the charge current waveform from the inductor.
2. The charging system of claim 1 further comprising a power converter operably coupled with an electrochemical device, the power converter to provide power to a load wherein the power converter is in operable communication with the controller, the controller to control the power converter to generate a leading edge shape of a discharge signal from the electrochemical device, the leading edge of the discharge signal shaped based on a frequency associated with a value representative of the flow of electrical current from the electrochemical device.
3. The charging system of claim 2 wherein the charge signal comprises a series of tuned charge pulses each with the shaped leading edge of the signal current waveform and the constant current body portion of the charge current waveform, and the discharge signal comprises a series of tuned discharge pulses each with the leading edge shape of the discharge signal, the controller to control the charge signal shaping circuit and the power converter to interleave the series of charge pulses with the series of discharge pulses.
4. The charging system of claim 3 wherein a tuned discharge pulse immediately follows a tuned charge pulse.
5. The charging system of claim 3 wherein a tuned discharge pulse of the series of tuned discharge pulses is activated during the constant current body portion of a tuned charge pulse of the series of tuned charge pulses.
6. The charging system of claim 2 wherein the power converter comprises at least one of a first buck converter or a first boost converter.
7. The charging system of claim 6 wherein the power converter further comprises at least one of a second buck converter in parallel with the first buck converter or a second boost converter in parallel with the first boost converter.
8. The charging system of claim 2 wherein the power converter comprises a switch to control the power converter, the switch receiving a control signal with a pulse width that varies from a mostly off pulse width to a mostly on pulse width to shape an edge of an output pulse from the load.
9. The charging system of claim 2 wherein the controller activates the power converter when the charge current waveform is off.
10. The charging system of claim 1 wherein the shaped leading edge defining an increasing charge current is of the shape of a sinusoid corresponding to a frequency associated with a value representative of a flow of electrical current to an electrochemical device.
11. The charging system of claim 10 wherein the PWM control signal has a controlled varying duty cycle or controlled varying period to produce the series of pulses to the inductor, wherein the increasing charge current produced from the inductor receiving the series of pulses generates the shape of the leading edge as the increasing charge current of the shape of the sinusoid corresponding to the frequency.
12. The charging system of claim 10 wherein the value is at least one of impedance, admittance and power.