Synthesis and Electrochemical Study of Cu-F Co-doped Li۴Ti۵O۱۲ (LTO) as Anodic Material in Li-ion Batteries

We report a new Li۴Ti۵-xCuxO۱۱.۷F۰.۳ (X= ۰.۱, ۰.۱۵, ۰.۲, ۰.۲۵, ۰.۳) anodic material for use in Li-ion battery. These modified LTO anodic materials were produced with the simple solid-state method. The electrochemical and morphological characterization of synthesized powders is checked with galvanostatic charge/discharge, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS)scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). Li۴Ti۴.۷۵Cu۰.۲۵O۱۱.۷F۰.۳ (LTCu۰.۲۵OF۰.۳), among all samples shows the best result in cyclability and rateability. The LTO, LTOF۰.۳ and LTCu۰.۲۵OF۰.۳ deliver discharge capacity of ۱۵۸.۳, ۱۵۱.۳, ۱۳۸.۸, ۱۲۲.۴, ۶۸.۵, ۳۵.۷ and ۱۷۶.۳, ۱۶۷.۷, ۱۵۷.۳, ۱۴۳.۹, ۱۰۱.۸, ۸۴.۱ and ۱۸۸.۸, ۱۸۰, ۱۶۹.۷, ۱۵۱.۲, ۱۱۶, ۱۰۵.۱ mAh .g-۱ at ۰.۱, ۰.۲, ۰.۵, ۱, ۳ and ۵C respectively, which the capacity discharge from LTCu۰.۲۵OF۰.۳ more than LTO and LTOF۰.۳ samples. The capacity retention of LTO, LTOF۰.۳ andLTCu۰.۲۵OF۰.۳ after ۱۰۰ cycles charge and discharge at ۱C is ۹۰.۸%, ۹۶.۳% and ۹۷.۳% respectively. This resualt indicates that substitution of Cu and F in Ti and O position have a positive synergistic effect on cyclability and rateability of LTO.