Synthesis and characterization of sulfur–carbon–vanadium pentoxide composites for improved electrochemical properties of lithium–sulfur batteries

Abstract Sulfur (S)–carbon (C)–vanadium pentoxide (V 2 O 5 ) composites were prepared by wet ball milling, and their physical and electrochemical properties were evaluated. Firstly, the effect of the carbon content of S–C composite electrodes on their physical and electrochemical properties was investigated. The S–C composite electrode with 60 wt.% S delivers a first discharge capacity of 1077 mAh g −1 . However, its capacity markedly decreases to 606 mAh g −1 after 10 cycles, which corresponds to a capacity fading rate of 47 mAh g −1 per cycle. To improve the electrochemical performance of the S–C composite electrode, carbon was partially replaced by V 2 O 5 . The S–C–V 2 O 5 composite electrode with a composition of 60 wt.%—S, 30 wt.%—V 2 O 5 and 10 wt.%—C exhibits a lower capacity fading rate of 23 mAh g −1 per cycle in the first 10 cycles and better capacity retention than the S–C composite electrode over 50 cycles.