Cellulose-assisted combustion synthesis of Li₄Ti₅O₁₂ adopting anatase TiO₂ solid as raw material with high electrochemical performance

Pure-phase spinel-type lithium titanate, Li₄Ti₅O₁₂, was successfully fabricated by cellulose-assisted glycine-nitrate (cellulose-GN) combustion process at reduced temperature using anatase TiO₂ solid as raw material of titanium. The influence of cellulose and impregnation sequence on the phase purity, particle size and electrochemical performance of Li₄Ti₅O₁₂ was investigated. The sequence of preparation was found to have big effect on the phase formation and electrochemical performance of the oxides. High-purity and well-crystallized Li₄Ti₅O₁₂ oxides were obtained at a calcination temperature of 750 °C via the sequence III, for which the cellulose was first adsorbed by the mixed solution of LiNO₃ and glycine followed by the impregnation of TiO₂ suspension. Compared with solid-state reaction, the cellulose-GN process produced the Li₄Ti₅O₁₂ oxides with smaller particle size and higher specific capacity due to the lower synthesis temperature. A reversible capacity of 103 mAh/g at 20 C rate and fairly stable cycling performance even at 40 C was achieved.