An In Situ Electrochemical Amorphization Electrode Enables High-Power High-Cryogenic Capacity Aqueous Zinc-Ion Batteries

Quick-charge technology is of great significance for the development of aqueous zinc-ion batteries. In this study, an unreported in situ electrochemical amorphization mechanism is highlighted to unlock the ultrafast-kinetics electrode. Multiple characterizations, density functional theory calculation, and molecular dynamic simulation are applied to uncover the storage mechanism of electrodes, as well as the evolution of structure, and reaction kinetics after reconstruction. As revealed, the long-range ordered ZnV₂O₄ crystalline can be reconstructed to a short-range ordered Zn_0.44V₂O₄ electrode, which exhibits significantly improved active sites, shortened diffusion path, and enhanced zinc ions capture ability. Notably, by pairing with the modified Zn anode, it can display ultrahigh rate capability (212 mAh g⁻¹ at 50 A g⁻¹) with a maximum power density of 23.2 kW kg⁻¹, as well as good cycle performance (217.2 mAh g⁻¹ after 3000 cycles at 20 A g⁻¹). Unexpectedly, such reconstructed amorphous electrodes can also retain superior storage capability even at cryogenic conditions. A high specific capacity of 251 mAh g⁻¹ can be delivered at −25°C and 1 A g⁻¹, as well as an 84.3% capacity retention after 500 cycles. This brand-new in-situ electrochemical amorphization mechanism is expected to provide new insight into understanding the high-performance aqueous zinc-ion batteries.