Li4Ti5O12 Nanoshell on TiO2 Nanofibers as a Durable Anode for Li-Ion Battery Energy Storage

TiO2(B), despite its high theoretical capacity, suffers from a dramatic initial irreversible capacity loss (ICL), thus hindering its application as an anode material in lithium-ion batteries (LIBs). In this work, we successfully construct a Li4Ti5O12 nanoshell on TiO2 nanofibers, in which the pristine TiO2 nanofibers are mixed phases of TiO2(B) and anatase TiO2. Benefiting from the effective protection of the TiO2 surface by the Li4Ti5O12 nanoshell and the presence of abundant Li4Ti5O12/TiO2 nanointerfaces, the resulting Li4Ti5O12–TiO2 nanofibers (LTO–TiO2) demonstrate negligible ICL with enhanced rate capability and consistent performance over prolonged cycles. This work not only demonstrates that LTO–TiO2 can be utilized as a viable LIB energy storage material with high energy density (380 W h kg–1) but also gives an insight into the strategy of using Li4Ti5O12 as a nanoshell to mitigate the SEI formation and eliminate the initial irreversible capacity loss of other electrodes.