Implementation of a low-cost electrochemical impedance spectroscope

The paper describes an implementation of a low-cost electrochemical impedance spectroscope using a sound card on a computer. The main parts of the system are: PC's sound card used for signal output and data acquisition, a current source, two measurement channels, software module for battery parameter estimation. The sinusoidal signal with required amplitude and frequency is generated from the MATLAB and using the D/A converter of the sound card. The current source is implemented as a class AB amplifier with a PI regulator. Measurement channels are designed to prepare battery response signals for the A/D conversion. The implementation allows utilizing different algorithms for parameters estimation. The system performance is demonstrated when used to estimate the parameters of a Lead-Acid battery, test results are presented and discussed.