LAUSR

To improve the cycle performance, [email protected] (z = 0, 1, 3 and 5 mol%) (“@” means “was coated on the surface of”) cathode materials have been successfully prepared via a syn-lithiation strategy. The high-resolution transmission electron microscope (HRTEM) structural analysis results show that Li2TiO3 is evenly coated on the surface of LiNi0.5Mn0.5O2, with the thickness of the coating layer of approximately 10 nm. The electrochemical characterizations of the synthesized [email protected] suggest that 1 mol% [email protected] electrode shows the best electrochemical performance, including the highest capacity and best cycle stability and rate performance. The capacity retention at 25 °C is improved by approximately 23% by the 1 mol% Li2TiO3 coating. The improved cycling performance of LiNi0.5Mn0.5O2 arises from the presence of the Li2TiO3 surface layer, which suppresses the direct contact between the active materials and the electrolytes, enhances the lithium ion diffusion through the electrode/electrolyte interface, expands the BET area, stabilizes the structure and prevents the pulverization of the active materials during repeated charging/discharging. The XPS results showed that Li2TiO3 coating layer could inhibit electrolyte decomposition, and the decomposition of electrolyte on the surface of coating electrode is different from that of LiNi0.5Mn0.5O2 electrode.