Polyvinylpyrrolidone‐Mediated In Situ Synthesis of Well‐Connected Ni 3 V 2 O 8 /C Nanocomposite Anode for Lithium‐Ion Batteries

A Ni 3 V 2 O 8 /C nanocomposite (nano‐NVO/C) is prepared using a facile solvothermal and postcalcination method, in which polyvinylpyrrolidone (PVP) is adopted as the carbon source and simultaneously prevents the aggregation of Ni 3 V 2 O 8 nanoparticles to enable in situ formation of highly dispersed Ni 3 V 2 O 8 nanoparticles around amorphous C. Microstructural characterization shows that elastic amorphous C serves as filler to fill the voids within Ni 3 V 2 O 8 nanoparticles, bridging the Ni 3 V 2 O 8 nanoparticles, improving electron transport ability, and withstanding the crystal stress coming from Li + insertion/extraction. As a consequence, the electrochemical performances including discharge capacity, cycling stability, and rate capacity of nano‐NVO/C are greatly enhanced, delivering a superior cycling capacity of 1284 mA h g −1 at a current density of 0.3 A g −1 after 300 cycles. Electrochemical kinetics studies show that the charge storage in nano‐NVO/C is controlled by the pseudocapacitive mechanism.