Preparation of pure and metal-doped Li4Ti5O12 composites and their lithium-storage performances for lithium-ion batteries

The poor rate performance of Li4Ti5O12 is still a big challenge for its commercialization due to the low electronic conductivity and bad Li + -ion diffusivity. Herein, the La3+-doped Li4-xLaxTi5O12 (x = 0, 0.03, 0.06, 0.09) anode materials have been prepared through a facile and rapid microwave heating route. The results reveal that doping La3+-ion into the crystal structure of Li4Ti5O12 can significantly improve the electronic conductivity and facilitate the Li +/- -ion diffusion of Li4Ti5O12. Among the various La3+-doped materials, Li3.94L-a(0.06)Ti(5)O(12) anode shows the best lithium-storage performances. During the process of discharge/charge, the Li3.94L-a(0.06)Ti(5)O(12) anode exhibits a long discharge plateau at 1.55 V and an initial discharge capacity of 172.5 mAh g(-1) at 0.1C. Even at a high current density of 10C, it still shows a high specific capacity of 150.4 mAh g(-1). Moreover, it can maintain a reversible capacity of 142.5 mAh g(-1) at 20C after 300 cycles with a high capacity retention of about 96.5%.