Long-life and high-rate Li3V2(PO4)3/C nanosphere cathode materials with three-dimensional continuous electron pathways

Abstract

Lithium-ion batteries (LIBs) are receiving considerable attention as storage devices in the renewable and sustainable energy developments. However, facile fabrication of long-life and high-rate cathode materials for LIBs is required to facilitate practical application. Here we report a favourable way to synthesize a Li₃V₂(PO₄)₃/C nanosphere cathode with three-dimensional (3D) continuous electron pathways by synergistically utilizing polyethyleneglycol (PEG) and acetylene black for carbon coating and conductive network construction. The as-prepared cathode material has a discharge capacity of 142 mA h g⁻¹ at 1 C rate, approaching its theoretical value (150 mA h g⁻¹), and can even be cycled at a rate as high as 30 C without capacity fading. After 1000 cycles at a rate of 5 C, the as-prepared material has a capacity retention of up to 83%, and can also tolerate 5000 cycles with a considerable capacity, demonstrating excellent cycling stability. Our work shows that this material has great potential for high-energy and high-power energy storage applications, and this rational method can be applied to synthesize high-performance cathode materials on a large scale.