AbstractInstrumentation is reported for measuring electromotive force (EMF) from a high-impedance solid electrolyte-based electrochemical cell. Generally, concentration galvanic cells are used to study the high-temperature thermochemical properties of materials. The thermochemical results are determined by precise measurement of the high-impedance EMF and temperature of the electrochemical cell with suitable user interface software for data acquisition. The data are conditioned and processed using the unique design of the hardware and sent to a computer through the serial port. Online graphical displays of the data, averaging, trend viewing, and storage, are performed using a graphical user interface (GUI). The instrumentation was validated by conducting experiments with different materials using an electrochemical cell and its performance was demonstrated to be on par with commercial instruments. This work has enables low-cost sophisticated EMF measurements for determining the thermochemical properties of materials.