Reversible hydroxyzinc sulfate hydrate deposition/dissolution in electrochemical process could be observed on cathode surface. Good long term stability retention could also be achieved at high current density of 20 A g ⁻¹ .

Metal anodes hold significant promise for next-generation energy storage, yet achieving highly reversible plating/stripping remains challenging due to dendrite formation and side reactions. Here we present a tailored electrolyte design to surpass 99.9% Coulombic efficiency (CE) in zinc metal anodes by co-engineering salts and solvents to address two critical factors: plating morphology and the anode-electrolyte interface. By integrating a dual-salt approach and organic co-solvent design, these issues can be effectively addressed. The resulting hybrid dual-salt electrolyte renders CE of 99.95% at 1 mA cm⁻² at a medium concentration (3.5 m). Building upon the near-unity CE, an anode-free cell with ZnI₂ cathode can stably run more than 1000 cycles under practical conditions with minimal capacity loss. Our findings provide a promising pathway for the design of reversible metal anodes, advancing metal-based battery technologies for broader energy storage applications.

A guest engineering strategy is used to regulate the interlayer binding energy between vanadium oxide layers, thus thermodynamically suppressing vanadium dissolution. The as-prepared compound (NH ₄ ) ₂ V ₆ O ₁₆ ·1.5H ₂ O restrains the vanadium dissolution effectively.

The alkaline zinc-based batteries with high energy density are becoming a research hotspot. However, the poor cycle stability and low-rate performance limit their wide application. Herein, ultra-thin CoNiO₂nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays (O_d-CNO@Ni NTs) is used as a positive material for rechargeable alkaline Ni–Zn batteries. As the highly uniform Ni nanotube arrays provide a fast electron/ion transport path and abundant active sites, the O_d-CNO@Ni NTs electrode delivers excellent capacity (432.7 mAh g⁻¹) and rate capability (218.3 mAh g⁻¹at 60 A g⁻¹). Moreover, our O_d-CNO@Ni NTs//Zn battery is capable of an ultra-long lifespan (93.0% of initial capacity after 5000 cycles), extremely high energy density of 547.5 Wh kg⁻¹and power density of 92.9 kW kg⁻¹(based on the mass of cathode active substance). Meanwhile, the theoretical calculations reveal that the oxygen defects can enhance the interaction between electrode surface and electrolyte ions, contributing to higher capacity. This work opens a reasonable idea for the development of ultra-durable, ultra-fast, and high-energy Ni–Zn battery."Image missing"<!-- image only, no MathML or LaTex -->