Zr-doped Li4Ti5O12 particles coated with reduced graphene oxide nanolayer as anode for high-rate lithium-ion batteries

Lithium titanate (Li₄Ti₅O₁₂/LTO) has been widely recognized for its superior stability and long cycle life as a negative electrode material for lithium-ion batteries. However, its limited specific capacity and poor rate performance have hindered broader applications. This study introduces an innovative approach to address these limitations by preparing Zr-doped Li₄Ti₅O₁₂ coated with reduced graphene oxide (rGO) (LTO-0.1Zr@rGO) using a wet chemical method combined with freeze-drying technology. The incorporation of Zr ions into the LTO lattice resulted in an increase in the lattice parameter and the unit cell volume. This increase facilitated the transmission of lithium ions and enhanced the material's conductivity. Furthermore, the rGO coating was found to significantly enhance the rate performance and cycle stability of the material. The LTO-0.1Zr@rGO composite demonstrated a high rate capacity ranging from 396.5 to 263.6 mAh g⁻¹ at current densities varying from 0.2 to 5.0 A g⁻¹, with a stable capacity of 310.2 mAh g⁻¹ maintained after 1000 cycles at a current density of 1.0 A g⁻¹. These results indicate the potential of LTO-0.1Zr@rGO as a promising anode material for high-rate and stable lithium-ion batteries.