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

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 angstrom) and high diffusion coefficient, exhibits high energy density (374.3Wh kg(-1)) and power density (9000 W kg(-1)) aswell 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.