Approaching the Theoretical Capacity of Li3VO4 via Electrochemical Reconstruction

Li3VO4 is a potential anode for Li-ion batteries owing to its safe discharge plateau and high capacity, but the reported reversible capacity is still far from its theoretical value (592 mAh g(-1)). Here, for the first time, a Li3VO4 anode is reported with reversible capacity approaching the theoretical value. Li3VO4 aggregates hybridized with carbon (Li3VO4/C) are first fabricated, and then dramatically transform into well dispersed Li3VO4 nanocrystals (NCs) anchoring on carbon nanoflakes (NFs) by electrochemical reconstruction. In the Li3VO4/C NC-on-NF structures, the small-sized Li3VO4 NCs, the flexible carbon NFs, and the good dispersity provide high Li-ion storage, electronic conductivity and stability, respectively. Resultingly, outstanding electrochemical performance of the Li3VO4/C is achieved with discharge and charge capacities of 542 and 541 mAh g(-1) after 300 cycles at a specific current of 150 mA g(-1). After 1000 cycles at a specific current of 2000 mA g(-1), the discharge and charge capacities are maintained at 422 and 421 mAh g(-1). When matching with a 4 V cathode, the specific energy density of the Li3VO4/C is 4.2 times of Li4Ti5O12 and 1.2 times of graphite, and the volumetric energy density is 3.2 times of Li4Ti5O12 and 1.4 times of graphite.