Prominent long-life and high-rate performance rendered by crystallized Li3VO4 embedded in amorphous carbon nanoflakes

Abstract

While the reaction activity of Li₃VO₄ could be improved by a reduction in particle size, the enhanced surface defects will degrade the cyclability. It is very challenging to achieve the best balance between high-rate performance and long lifespan. Herein we designed a novel architecture of crystallized Li₃VO₄ nanoparticles embedded in carbon nanoflakes (mc-LVO/C NFs) through an improved electrostatic spray method. The as-prepared mc-LVO/C NFs exhibit comprehensive high capacity and long-life performance at high-rate, with the integral 2D morphology and the specific LVO embedded architecture promoting fast reaction kinetics, and the crystallized LVO rendering high and stable reactivity. It delivers a high capacity of 610 mA h g⁻¹ at 0.5 A g⁻¹, without obvious capacity delay over 500 cycles. After 7 periods from 0.2 to 10 A g⁻¹ over 570 cycles, a high capacity of 790 mA h g⁻¹ could be restored when reverting the current density to 0.2 A g⁻¹. Even cycling at a high discharge/charge current of 10/8 A g⁻¹, the mc-LVO/C NFs could deliver stable cycling over 10 000 cycles, delivering high capacity of 204 mA h g⁻¹. Combining the advantages of high reactivity and the high stability of LVO in an electrode may be referential for the design of advanced LVO-based electrodes.