Electrochemical impedance spectroscopy current measurement system calibration

A method for calibrating an electrochemical impedance spectroscopy (EIS) current measurement system, the method comprising:

• measuring a first voltage across a calibration resistor and a second voltage across a sense resistor arrangement, wherein a first current through the calibration resistor is equal to the first current through the sense resistor arrangement, wherein the calibration resistor has a specified resistance and an unspecified reactance and wherein the sense resistor arrangement has an unspecified resistance and an unspecified reactance;
• measuring a third voltage across a reactive element and a fourth voltage across the sense resistor arrangement, wherein a second current through the reactive element is equal to the second current through the sense resistor arrangement, wherein the reactive element has a specified reactance and an unspecified resistance;
• and
• calculating, using the first voltage, the second voltage, the third voltage, and the fourth voltage, a calibrated resistance value and a calibrated reactance value of the sense resistor arrangement.

A calibration system for calibrating an electrochemical impedance spectroscopy (EIS) current measurement system, the calibration system comprising:

• a calibration resistor, having a specified resistance and an unspecified reactance;
• a reactive element having a specified reactance and an unspecified resistance;
• a current source, configured to provide a specified current through the reactive element, through the calibration resistor, and through a sense resistor arrangement of the EIS current measurement system to be calibrated, wherein the sense resistor arrangement has a resistance and a reactance;
• and
• voltage measurement circuitry, configured to measure (1) a first voltage across the calibration resistor and a second voltage across the sense resistor arrangement while the current source provides a first current and (2) a third voltage across the reactive element and a fourth voltage across the sense resistor arrangement while the current source provides a second current, wherein the first voltage, the second voltage, the third voltage, and the fourth voltage are used to determine a calibrated resistance value and a calibrated reactance value associated with the sense resistor arrangement, wherein the calibrated resistance value and the calibrated reactance value are determined at more than one frequency.