A possible shortcoming of the CIP-DFT method is the definition of the electrode bulk region used for measuring or controlling the inner potential. While this is easy for simple electrodes, defining the bulk region uniquely can be challenging for intercalation electrodes used in battery applications, porous materials found in supercapacitors, and commonly used carbon electrodes, for example. In addition, the inner potential region needs to be chosen carefully also for other complex electrodes encountered in e.g. battery materials, such as metal/solid electrolyte interphase/electrolyte interfaces or electroplated dendrites. An additional difficulty is that the inner potential of semiconductor electrodes depends on the presence of defects. We demonstrated that the CIP-DFT method achieves electrode potential control in simple semiconductor electrode systems and expect it to work for defected materials as well, but the definition of the electrode bulk might need reconsideration and a larger simulation cell might be necessary to obtain a converged bulk inner potential.