Binary additives strategy for inhibiting cation dissolution and hydrogen bond reconstruction to boost high-performance aqueous zinc-ion battery

Aqueous zinc ion batteries (ZIBs) receive widespread attention due to the environmental friendliness, sustainability and high capacity. Nevertheless, the sluggish kinetic and structural degradation of cathode, along with the dendrite growth and hydrogen evolution reaction issues at zinc-metal anode severely limit the development of aqueous ZIBs. Herein, ammonium sulfate ((NH 4 ) 2 SO 4 ) and pyrrolidine-3-carboxylic (PCA) acid are developed as electrolyte additives to simultaneously solve the above problems. Theoretical calculations and experimental results demonstrate that the introduction of NH 4 + successfully stabilizes the structure of the NH 4 V 4 O 10 cathode material, while PCA induces the selective growth of the (002) plane of Zn for the homogeneous Zn deposition, enabling stable cycling life for Zn||Zn symmetric cell. Meanwhile, the hydrogen network is reconstructed to anchor the active water molecules for the suppression of side reactions. Owing to the synergic effect of (NH 4 ) 2 SO 4 and PCA binary additives, the Zn||NH 4 V 4 O 10 full cell exhibits outstanding cyclic stability for more than 1000 cycles at 2 A g −1 . This work provides a novel and low-cost approach for the electrolyte design of high performance aqueous ZIBs.