Improvement of Cycle Capability of VS₄ by Addition of Phosphorus Element

抄録

Vanadium tetrasulfide (VS₄) have been attracting attention as the promising positive electrode material for next generation batteries because of its high theoretical capacity (1196 mAh g⁻¹). In this study, a typical element (i.e., Phosphorus) was introduced into VS₄ for an attempt to improve the electrochemical cycle performance of VS₄. The prepared P_xVS_y showed significant increase in cycle capability; e.g., ca. 70 % after 50 cycles for P_0.4VS_5.0 sample cell, being much higher than that of pristine VS₄ cell (ca. 10 %). The PDF (pair distribution function) analyses indicated that the structural reversibility of VS₄ for Li insertion/extraction reactions was improved by the phosphorus addition.