Electrochemical measurements are powerful tools widely used in energy and bio related industries. For most of the cases, what we do is to control variables such as the potential or current and then measure the response of the system, or study the relationship between the potential and current. The measured responses contain information of the thermodynamics, kinetics, or transport properties pertaining to the system. These properties are necessary for the fundamental understanding of physical processes such as energy conversion, energy storage, or cell metabolism. These insights can facilitate the improvement of energy conversion efficiency, sensor accuracy, and device durability.