The use of storage systems is increasing in many applications. At the same time, new technologies for realizing storage devices are being proposed every year. Lithium-ion capacitor (LiC) cells can be included in these innovative technologies. In this study, extensive experimental research was carried out to determine the performance characteristics of LiC cells for practical applications. This study assessed the preliminary results of characterization tests to evaluate the performance of LiC cells over wide temperature and frequency ranges. In order to characterize the cells at different frequencies, galvano-electrochemical impedance spectroscopy (EIS) was performed at different temperatures and polarization voltages. Tests were performed on both laminated and prismatic cells in order to compare their behaviors. Finally, the experimental results were analyzed in order to assess the potential applications of this storage technology.