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.