Sol-assisted spray-drying synthesis of porous Li 3 V 2 (PO 4 ) 3 /C microspheres as high-activity cathode materials for lithium-ion batteries

Herein, porous Li3V2(PO4)3/C microspheres made of nanoparticles are obtained by a combination of sol spray-drying and subsequent-sintering process. Beta-cyclodextrin serves as a special chelating agent and carbon source to obtain carbon-coated Li3V2(PO4)3 grains with the size of ca. 30–50 nm. The unique porous structure and continuous carbon skeleton facilitate the fast transport of lithium ion and electron. The Li3V2(PO4)3/C microspheres offer an outstanding electrochemical performance, which present a discharge capacity of 122 mAh g−1 at 2 C with capacity retention of 96% at the end of 1000 cycles and a high-rate capacity of 113 mAh g−1 at 20 C in the voltage window of 3.0–4.3 V. Moreover, the Li3V2(PO4)3/C microspheres also give considerable cycling stability and high-rate reversible capacity at a higher end-of-charge voltage of 4.8 V.