The charge and discharge characteristics of LiNiO2 and LiMn2O4 have been investigated in mixed carbonate-based electrolyte solutions. The discharge capacity depended on the electrolytic salt. The order of the capacity, LiCF3SO3 < LiPF6 less than or equal to LiClO4, which is common to both electrodes, is partly consistent with that of the ionic conductivity of the solution. The solvent composition also affected the charge and discharge behavior. However, the order in the capacity did not strictly coincide with that of the ionic conductivity of the electrolyte. Moreover the details of the influence of the electrolyte composition was somewhat different between the oxide electrodes. The ac impedance at the electrode/electrolyte interface varied with the electrolyte composition. It showed that higher discharge capacities are obtained in electrolyte solutions which show lower interfacial resistances.