In situ deposition method preparation of Li4Ti5O12-SnO2 composite materials for lithium ion batteries

A Li4Ti5O12-SnO2 composite anode material for lithium-ion batteries has been prepared by loading various amounts of nano-SnO2 on Li4Ti5O12 to obtain composite materials with improved electrochemical performance relative to Li4Ti5O12 and SnO2. The composite materials were characterized by XRD, IR and SEM. The results indicated that SnO2 particles have encapsulated on the surface of the Li4Ti5O12 uniformly and tightly. The influence of SnO2 proportion on the electrochemical properties of Li4Ti5O12-SnO2 composite material was investigated and discussed. The results showed that Li4Ti5O12-SnO2 (5%) has the best cycling behavior among all the samples. At a current rate of 0.5 mA cm(-2), the material delivered a discharge capacity of 189 mAh g(-1) after 42 cycles. Electrochemical results indicated that the Li4Ti5O12-SnO2 composites increased the reversible capacity of Li4Ti5O12 and cycling retiability of the SnO2 anode material. It suggests the existence of synergistic interaction between Li4Ti5O12 and SnO2 and that the capacity of the composite is not a simple weighted sum of the capacities of the individual components. (c) 2007 Elsevier B.V. All rights reserved.