US 9,312,577 B2 · Circuits and methods for determination and control of signal transition rates in electrochemical cells

Abstract

A charge/discharge input is for respectively supplying charge to, or drawing charge from, an electrochemical cell. A transition modifying circuit is coupled between the charge/discharge input and a terminal of the electrochemical cell and includes at least one of an inductive constituent, a capacitive constituent and a resistive constituent selected to generate an adjusted transition rate on the terminal sufficient to reduce degradation of a charge capacity characteristic of the electrochemical cell. A method determines characteristics of the transition modifying circuit. A degradation characteristic of the electrochemical cell is analyzed relative to a transition rate of the charge/discharge input applied to the electrochemical cell. An adjusted transition rate is determined for a signal to be applied to the electrochemical cell that will reduce the degradation characteristic. At least one of an inductance, a capacitance, and a resistance is selected for the transition modifying circuit to achieve the adjusted transition rate.

Claims22

Dependent claims

A circuit, comprising:

one or more electrochemical cells;
a charge/discharge circuit configured to respectively generate charge pulses and discharge pulses to the one or more electrochemical cells, wherein the charge pulses and discharge pulses include a first transition rate;
and
a transition modifying circuit operably coupled between the charge/discharge circuit and a terminal of the one or more electrochemical cells, the transition modifying circuit comprising at least one circuit element configured to receive and modify the charge pulses and discharge pulses to exhibit an adjusted transition rate on the terminal that is slower than the first transition rate and sufficient to reduce degradation of one or more charge capacity characteristics of the one or more electrochemical cells, wherein the first transition rate and the adjusted transition rate include rise and fall times for their respective pulses.

1 more element

A method of determining characteristics of a transition modifying circuit, comprising:

repeatedly applying a charge pulse and a discharge pulse over an analysis period to each of:
a first transition modifying circuit configured to receive the charge pulse and the discharge pulse and generate a first transition rate on a first signal applied to a first electrochemical cell;
and
a second transition modifying circuit configured to receive the charge pulse and the discharge pulse and generate a second transition rate on a second signal applied to a second electrochemical cell, wherein the second transition rate is different from the first transition rate, and wherein the first transition rate and the second transition rate include rise and fall times for their respective pulses;
determining capacity loss of each of the first electrochemical cell and the second electrochemical cell after the analysis period;
repeating the repeatedly applying, and the determining the capacity loss, to determine a loss trend for each of the first electrochemical cell and the second electrochemical cell;
and
selecting components for the transition modifying circuit responsive to the loss trend of the first electrochemical cell and the loss trend of the second electrochemical cell.

5 more elements

Dependencies are inferred from the claim text.

Circuits and methods for determination and control of signal transition rates in electrochemical cells

Life of this patent

Circuits and methods for determination and control of signal transition rates in electrochemical cells

Life of this patent

Abstract

Claims22