Synthesis and electrochemical performances of Li4Ti4.95Al0.05O12/C as anode material for lithium-ion batteries Original Research Article

Spinel compounds Li4Ti5−xAlxO12/C (x=0, 0.05) were synthesized via solid state reaction in an Ar atmosphere, and the electrochemical properties were investigated by means of electronic conductivity, cyclic voltammetry, and charge–discharge tests at different discharge voltage ranges (0–2.5 V and 1–2.5 V). The results indicated that Al3+ doping of the compound did not affect the spinel structure but considerably improved the initial capacity and cycling performance, implying the spinel structure of Li4Ti5O12 was more stable when Ti4+ was substituted by Al3+, and Al3+ doping was beneficial to the reversible intercalation and deintercalation of Li+. Al3+ doping improved the reversible capacity and cycling performance effectively especially when it was discharged to 0 V.