Li4Ti5O12 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement of X-ray diffraction (XRD) results show that the proportion of Li occupying 16d sites is extraordinary low and the lattice constants of LTO and R-TiO2 change with the titanium dioxide content. EIS measurements showed that with increasing R-TiO2 content, both its charge transfer impedance (R ct) and lithium ion diffusion coefficient (D Li) decreased. The changes of R ct and D Li caused by the increase of titanium dioxide content have synergic-antagonistic effects on the rate and cycle properties of Li4Ti5O12. The rate performance is positively related to D Li, while the cycle property is negatively correlated with R ct, indicating that the rate performance is mainly related to D Li, while R ct more significantly affects the cycle performance. LTO-RT-17.06% exhibited excellent rate properties, especially under a high current density (5.0 C, 132.5 mAh/g) and LTO-RT-34.42% showed superior long-term cycle performance (0.012% capacity loss per cycle) compared to that of LTO-RT-17.06% and LTO-RT-23.69%.