An investigation of polypyrrole–LiV3O8 composite cathode materials for lithium-ion batteries

A novel lithium trivanadate/polypyrrole (LiV3O8–PPy) composite, suitable for lithium-ion battery cathodes, was synthesized by dispersing LiV3O8 and PPy powders in ethanol followed by heating. The polypyrrole acts as a conducting matrix, a binder and an active material, as well as a volume change buffer agent, which holds the LiV3O8 particles in place during the charge/discharge cycles. The new material was characterized by scanning electron microscopy. It was found that polypyrrole particles were uniformly distributed among the LiV3O8 powders, which could significantly enhance the electrical conductivity and stability of the composite electrode. The composite containing 20 wt% PPy exhibits a good reversibility, higher coulombic efficiency and better cycle life than the bare LiV3O8 electrode.