F doped Li3VO4: An advanced anode material with optimized rate capability and durable lifetime

Li 3 VO 4 is one of the most promising candidates for high performance lithium-ion batteries due to its high specific capacity and excellent ionic conductivity , while its practical applications are hindered, because of its inferior rate capability. Herein, we adopted an anionic doping strategy to improve electronic conductivity, cycling stability and accelerate electrochemical kinetics. A series of F − doped Li 3 VO 4 samples were synthesized by a modified sol-gel method for the first time. F − doping led to the appearance of oxygen vacancies and reduced band gap, which effectively improve electronic conductivity. Complete structural rearrangement and optimized SEI layers also occurred during cycling, beneficial for stable lifetime. As a consequence, long cycle life (cycling 1100 loops at 500 mA g −1 except for the first 5 loops at 100 mA g −1 ) and optimized rate capability (255 mA h g −1 at 1000 mA g −1 ) were achieved for 5 at% F doping, which are superior to those for undoped samples. This work demonstrates that anion doping is a feasible strategy to accelerate electrons/ions transfer and improve cycling stability of Li 3 VO 4 .