Pure spinel lithium titanate,Li4Ti5O12 phase,was successfully synthesized from commercial rutile TiO2 at reduced temperature (800 ℃) via a cellulose assisted combustion process and surface activation of TiO2 by acid treatment.A treatment of rutile TiO2 by strong nitric acid significantly improved the lithium insertion capability and kinetics,consequently,a calcination temperature as low as 800℃ is sufficient to obtain a phase-pure Li4Ti5O12.The reason of improved lithium insertion properties of rutile TiO2 after the acid treatment was investigated.Cellulose-GN process presented the production with small particle-size and high specific capacity,leading to a reversible discharge capacity of ~ 175 mAh g-1 at 1 C rate,near the theoretical value.Furthermore,the resulted oxide showed promising high rate performance with a discharge capacity of ~100 mAh g-1 at 10 C rate and high cycling stability.