Large volumetric expansion of cathode hosts and sluggish transport kinetics in the cathode–electrolyte interface, as well as dendrite growth and hydrogen evolution at Zn anode side are considered as the system problems that cause the electrochemical failure of aqueous Zn-vanadium oxide battery. In this work, a multifunctional anti-proton electrolyte was proposed to synchronously solve all those issues. Theoretical and experimental studies confirm that PEG 400 additive can regulate the Zn2+ solvation structure and inhibit the ionization of free water molecules of the electrolyte. Then, smaller lattice expansion of vanadium oxide hosts and less associated by-product formation can be realized by using such electrolyte. Besides, such electrolyte is also beneficial to guide the uniform Zn deposition and suppress the side reaction of hydrogen evolution. Owing to the integrated synergetic modification, a high-rate and ultrastable aqueous Zn-V2O3/C battery can be constructed, which can remain a specific capacity of 222.8 mAh g−1 after 6000 cycles at 5 A g−1, and 121.8 mAh g−1 even after 18,000 cycles at 20 A g−1, respectively. Such “all-in-one” solution based on the electrolyte design provides a new strategy for developing high-performance aqueous Zn-ion battery.

The ripple effect induced by uncontrollable Zn deposition is considered as the Achilles heel for developing high-performance aqueous Zn-ion batteries. For this problem, this work reports a design concept of 3D artificial array interface engineering to achieve volume stress elimination, preferred orientation growth and dendrite-free stable Zn metal anode. The mechanism of MXene array interface on modulating the growth kinetics and deposition behavior of Zn atoms were firstly disclosed on the multi-scale level, including the in-situ optical microscopy and transient simulation at the mesoscopic scale, in-situ Raman spectroscopy and in-situ X-ray diffraction at the microscopic scale, as well as density functional theory calculation at the atomic scale. As indicated by the electrochemical performance tests, such engineered electrode exhibits the comprehensive enhancements not only in the resistance of corrosion and hydrogen evolution, but also the rate capability and cyclic stability. High-rate performance (20 mA cm−2) and durable cycle lifespan (1350 h at 0.5 mA cm−2, 1500 h at 1 mA cm−2 and 800 h at 5 mA cm−2) can be realized. Moreover, the improvement of rate capability (214.1 mAh g−1 obtained at 10 A g−1) and cyclic stability also can be demonstrated in the case of 3D MXene array@Zn/VO2 battery. Beyond the previous 2D closed interface engineering, this research offers a unique 3D open array interface engineering to stabilize Zn metal anode, the controllable Zn deposition mechanism revealed is also expected to deepen the fundamental of rechargeable batteries including but not limited to aqueous Zn metal batteries.

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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 Zn0.44V2O4 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.

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