A high performance all-vanadate-based Li-ion full cell

Abstract

Li₃VO₄ is regarded as a promising anode material for Li-ion batteries due to its advantages of safety and low volumetric variation. However, unscalable synthesis makes the practical application of Li₃VO₄ challenging. Herein, state-of-the-art Li₃VO₄/N doped C porous microspheres comprising Li₃VO₄ nanoparticles encapsulated in interconnected N doped C networks (LVO/NC PMSs) are designed and synthesized via a scalable spray drying approach. Ultra-high capacity, ultra-long cycle life and prominent rate capability are achieved in the LVO/NC PMS electrode. When cycling at 0.1 A g⁻¹, it delivers a reversible capacity of 610 mA h g⁻¹ after 200 cycles. At a high constant charge current of 2.0 A g⁻¹, it delivers stable cycling over 5000 cycles at a high discharge current of 4.0 A g⁻¹, and the reversible capacity is completely restored after 150 cycles of rate performance testing with discharge current from 0.2 to 4.0 A g⁻¹. Moreover, Li₃V₂(PO₄)₃ microspheres (LVP MSs) are also prepared using the scalable spray drying approach, and a new all-vanadate-based LVO//LVP full cell is designed for the first time. The full cell delivers a high energy density of 300 W h kg⁻¹ which is higher than that of most of the Li₄Ti₅O₁₂ and LVO-based full cells, and a long lifespan (340.7 mA h g⁻¹ after 1000 cycles at 1.0 A g⁻¹) which meets the requirements of commercialization. The scalable synthesis of LVO/NC PMSs and LVP MSs with excellent performance and the configuration of the LVO//LVP full cell with high energy density and long cycle life may pave the way for LVO for practical applications.