Resistivity of thin-film electrodes Si@O@Al and LiCoO$_2$

The results of measuring the resistivity of thin-film structures Ti|Si@O@Al|Ti and Ti|LiCoO$_2$|Ti by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) are presented. It was found that, according to the EIS data, the resistance of Ti|Si@O@Al|Ti is three orders of magnitude higher than the CV data, which is due to the nonohmic nature of the metal-semiconductor junction and the varistor effect. It is shown that the Ti–LiCoO$_2$ contact is ohmic, while the nonlinearity of the CVC is well described by the varistor effect. The results obtained are of importance for the interpretation of the impedance spectra of thin-film solid-state lithium-ion batteries based on semiconductor materials.