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The low electronic conductivity of spinel-structured Li 4 Ti 5 O 12 could be improved by introducing CuV 2 O 6 . Herein, several Li 4 Ti 5 O 12 /CuV 2 O 6 composites with different CuV 2 O 6 contents have been successfully prepared by a facile liquid-phase dispersion technique. The amount of CuV 2 O 6 in composites is shown to affect the particle size and electrochemical performances of Li 4 Ti 5 O 12 . The Li 4 Ti 5 O 12 /CuV 2 O 6 composite prepared with a 5 wt % CuV 2 O 6 content (referred to as 5 wt % Li 4 Ti 5 O 12 /CuV 2 O 6 ) exhibits the best electrochemical performances among all the Li 4 Ti 5 O 12 /CuV 2 O 6composites. The initial discharge/charge capacities of the 5 wt % Li 4 Ti 5 O 12 /CuV 2 O 6 composite reach 241.1/199.8 mAh g −1 and retain at 136.8/135.7 mAh g −1 over 500 cycles at 30 mA g −1 between 1.0 and 3.0 V. In addition, initial discharge/charge capacities of the 5 wt % Li 4 Ti 5 O 12 /CuV 2 O 6 composite amount to 129.8/90.5 mAh g −1 even at 1200 mA g −1 with maintained discharge/charge capacities of 71.1/71.1 mAh g −1 over 2500 cycles, which are superior to the pristine Li 4 Ti 5 O 12 in all cases. The detailed electrode kinetic analysis reveals that the introduction of the CuV 2 O 6 phase can enhance the lithium-ion transferring rate and cycling stability of Li 4 Ti 5 O 12 . The enhanced lithium-storage mechanism of the 5 wt % Li 4 Ti 5 O 12 /CuV 2 O 6 composite is clarified by in situ X-ray diffraction (XRD) analysis. The acquired data confirms that in situ formation of small amounts of metallic Cu during discharge/charge processes highly enhance the electronic conductivity and decreases the charge−transfer resistance of Li 4 Ti 5 O 12 . In sum, the as-obtained 5 wt % Li 4 Ti 5 O 12 /CuV 2 O 6 composite has potential for future construction of high-rate and long-lifespan anode materials for Li-ion batteries. The work also provides an innovative route to improve electrochemical performances of Li 4 Ti 5 O 12 . KEYWORDS: Li-ion batteries, Li 4 Ti 5 O 12 /CuV 2 O 6 composites, anode materials, liquid-phase dispersion technique, enhanced lithium storage performances

Summary Compared with traditional anode materials, spinel‐structured Li4Ti5O12 (LTO) with “zero‐strain” characteristic offers better cycling stability. In this work, by a wet‐chemistry synthesis method, LTO anode materials have been successfully synthesized by using CH3COOLi·2H2O and C16H36O4Ti as raw materials. The results show that sintering conditions significantly affect purity, uniformity of particle sizes, and electrochemical properties of as‐prepared LTO materials. The optimized LTO product calcined at 650°C for 20 hours demonstrates small particle sizes and excellent electrochemical performances. It delivers an initial discharge capacity of 242.3 mAh g−1 and remains at 117.4 mAh g−1 over 500 cycles at the current density of 60 mA g−1 in the voltage range of 1.0 to 3.0 V. When current density is increased to 1200 mA g−1, its discharge capacity reaches 115.6 mAh g−1 at the first cycle and remains at 64.6 mAh g−1 after 2500 cycles. The excellent electrochemical performances of LTO can be attributed to the introduction of rutile TiO2 phase and small particle sizes, which increases electrical conductivity and electrode kinetics of LTO. Therefore, as‐synthesized LTO in this study can be regarded as a promising anode candidate material for lithium‐ion batteries.