Internal-diffusion controlled synthesis of V2O5 hollow microspheres for superior lithium-ion full batteries

Abstract

Exploiting a simple and effective strategy to build shell-tuned hollow nanomaterials with unchanged surface microstructure is a great challenge but important for lithium-ion batteries (LIBs). Herein, we demonstrate the synthesis of V2O5 hollow microspheres, where the hierarchical shell thickness can be changed by controlling internal-diffusion rate of the core precursor. The fascinating nanostructures can guarantee the full contact with electrolyte with shortened ions diffusion path. Meantime, the self-created pores can effectively alleviate the volume change in the charge/discharge process. When evaluated as cathode materials, the V2O5 hollow microspheres can deliver a high reversible specific capacity of 287 and 140 mAh g−1 at 1/3 C and 10 C, respectively with a good cycling stability. After inserting Li+, the corresponding Li3VO4/CNTs nanoparticles are obtained as anode materials, also exhibiting a high specific capacity of 200 mAh g−1 even after 800 cycles at 1000 mA g−1. An all-vanadium-based lithium-ion full battery (V2O5//Li3VO4/CNTs) is assembled, which gives a high specific capacity of 55 mAh g−1 at 5000 mA g−1 even after 1000 cycles based on the cathode material weight.