Diagnosis and Modeling of the CuCl Electrolyzer Using Electrochemical Impedance Spectroscopy

Abstract

A CuCl/HCl electrolytic cell was operated at different temperatures to quantify the effect of temperature on the overall performance. Polarization curves and EIS data were taken at 40, 60 and 80 °C to observe the changes in ohmic, charge-transfer and interfacial resistance. Our research showed a significant increase in the cell performance as the temperature was increased from 40 to 80 °C. While the polarization data were used to observe the overall increase in the current density in a specific range of applied potential, the corresponding EIS data showed a decrease in the ohmic and charge transfer resistance. It was also observed that pressure applied on the end plates during cell assembly has a significant effect on the ohmic resistance. An optimum pressure of 6.3 psi (bolt torque: 20 Nm) showed the best performance. This paper demonstrates how changes in the signature of EIS spectra with temperature reflect the cell performance.