Fabrication of Metal-Doped Hierarchical Trimodal Porous Li3V2(PO4)(3)/C Composites with Enhanced Electrochemical Performances for Lithium-Ion Batteries

摘要

Na/Cr-doped Li3V2(PO4)(3)/C composites with a hierarchical trimodal porous structure, including micro-, meso-, and macropores, are synthesized by a feasible ice-templating method and investigated as cathodes for lithium-ion batteries (LIBs). Na and Cr doping decrease the charge transfer resistance of Li3V2(PO4)(3)/C and increase the diffusion coefficient of Li ions within the three-dimensional interconnected network, resulting in enhancement of both the capacity and rate performances of hierarchical porous Li3V2(PO4)(3)/C with maximized electrochemical performances at a doping level of x=0.04. Cr doping shows a higher enhancement than Na in the capacity of Li3V2(PO4)(3). As-prepared Cr-doped Li3V1.96Cr0.04(PO4)(3)/C shows the high capacity and rate performance of 116.8 mAh g(-1) at 10 C as well as an excellent cyclability. This work provides a simple and feasible method to fabricate metal-doped hierarchical trimodal porous cathode materials and deepens our understanding on design of high-performance electrode materials for LIBs.