A graphite/TiO2 full cell has been developed as a new safety energy storage system using a highly safety process. The crystal structures of the anatase TiO2 electrode have been investigated with respect to the performance of the electrodes. Due to the large anion intercalation into the graphite positive electrode, the possible charging potential can be raised to around 5.3V against the Li/Li+ electrode, which is a higher charging voltage than lithium-ion batteries (maximum voltage is around 4.3V vs. Li/Li+). In situ XRD measurements have been carried out on both the cathode and anode electrodes of the graphite/TiO2 cell during the charge process to elucidate the intercalation mechanism.