Engineering the interplanar spacing of ammonium vanadates as a high-performance aqueous zinc-ion battery cathode

Abstract

We report the engineering of the interplanar spacing of ammonium vanadates to achieve the optimal electrochemical performance as cathodes for aqueous zinc-ion batteries (ZIBs) and provide insights into the origin of the enhanced electrochemical behaviors. The NH₄V₄O₁₀ compound, with the largest interplanar spacing (9.8 Å) and high diffusion coefficient, exhibits high energy density (374.3 W h kg⁻¹) and power density (9000 W kg⁻¹) as well as superior long-term cycling performance (a discharge capacity of 255.5 mA h g⁻¹ can be maintained after 1000 cycles at 10 A g⁻¹). With the merits of impressive energy density and long cycle life, the NH₄V₄O₁₀ might be a new promising cathode for aqueous ZIBs for grid energy storage applications. This work provides a direction for choosing or designing the ideal high-performance cathode for aqueous ZIBs and other advanced battery systems.