Synthesis and assessment of the electrochemical performance of micro-nano-spherical Li4Ti5O12-LiAlO2 composites

Abstract

Although lithium titanate (Li4Ti5O12, LTO) is a promising anode material for fast charge/discharge lithium-ion batteries, its application is limited by the low Li diffusion coefficient and low electronic conductivity. In this work, the spray drying method was combined with solid-state calcination to prepare Li4Ti5O12 @LiAlO2 (LTO@LAO) composite anode electrode materials with micro and nano spherical structures. The formation of an ultrathin LAO coating of about 2 nm on the LTO surface was evident. The Li4Ti5O12 @LiAlO2 composite (3 wt%) exhibited an excellent specific capacity of discharge (156.5 at 10 C and 146.2 mAh/g at 20 C) compared with pristine LTO. Meanwhile, at 10 C rate, the specific capacity of the battery was maintained at 152.8 mAh/g after 500 charge/discharge cycles, and it retained 97% of the initial capacity. The smallest irreversible capacity was exhibited by the LMO/LTO-3 full cell with spinel LiMn2O4 as the positive electrode, which had a capacity retention rate of 98.79% after 100 cycles. Therefore, the low cost of synthesis, excellent rate capabilities, and remarkable cycling stability performance of the prepared LTO@LAO composite anode material make it an excellent candidate for application in high-power devices and energy storage systems.