Enhanced electrochemical performance of SrF2-modified Li4Ti5O12 composite anode materials for lithium-ion batteries

The commercial Li4Ti5O12 (LTO) is successfully modified by SrF2 via a low temperature coprecipitation process. The results indicate that Sr2+ and F− do not co-dope into the bulk phase of the LTO, but instead form a SrF2 coating layer on the surface of the LTO. The suitable SrF2 buffer layer could cover the catalytic active sites of the LTO and suppress the electrolyte reduction decomposition on the surface of the LTO, which means that the SrF2 modification is favorable to suppress gas generation of the LIBs using LTO as anode material during charge/discharge cycles and storage. Moreover, according to optimized the amount of SrF2, the 2 wt% of SrF2 in the SrF2 modified LTO composites exhibits the best rate capability and an excellent cyclic performance.