Electrochemical Impedance Spectroscopy System Based on a Teensy Board

This article describes a portable low-cost device for performing electrochemical impedance spectroscopy (EIS) measurements, which is based on an off-the-shelf TeensyDuino. The instrument does not make use of other components, such as operational amplifiers, so it can be readily set up by anyone having a Teensy device and some resistors. Teensy 3.2, Teensy 3.5, and Teensy 3.6 can be used to realize the EIS system. The instrument can measure the impedance in the frequency range from 0.01 to 50 000 Hz, and by selecting the shunt resistor, it can be adapted to different impedance values. No special instrumentation is required for the system calibration. The proposed system uncertainty is less than 5% for an impedance of up to $50 {~\mathrm {k\Omega }}$ , a value which is lower than the usual intrinsic uncertainty of most corrosion experiments.