Ti-supported RuN thin films, synthesized by rf-magnetron sputtering, have been electrochemically characterized, focusing in particular to their charge-storage capacity, and to the mechanisms that influence this important property, in view, e.g., of applications in supercapacitors. Based on cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) data, a deconvolution of non-faradic and faradic contributions has been attempted, and a mechanism for the charging/discharging process has been proposed