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Rechargeable aqueous sodium ion batteries (ASIBs) are rising as an important alternative to lithium ion batteries, owing to their safety and low cost. Metal anodes show a high theoretical capacity and nonselective hydrated ion insertion for ASIBs, yet their large volume expansion and sluggish reaction kinetics resulted in poor electrochemical stability. Herein, we demonstrate an electrode cyclability enhancement mechanism by inlaying bismuth (Bi) nanoparticles on graphene nanosheets through chemical bond, which is achieved by a unique laser induced compounding method. This anchored metal‐graphene heterostructure can effectively mitigate volume variation, and accelerate the kinetic capability as the active Bi can be exposed to the electrolyte. Our method can achieve a reversible capacity of 122 mAh g−1 at a large current density of 4 A g−1 for over 9500 cycles. This finding offers a desirable structural design of other metal anodes for aqueous energy storage systems. [ABSTRACT FROM AUTHOR]

Aqueous zinc metal batteries are receiving broad attention owing to their promising characteristics of low cost, high safety, and environmental benignity. However, severe side reactions over zinc metal anodes (i.e., dendrite growth and by‐product formation) dramatically limit their further development. Herein, the key problems are tackled by introducing a dual‐function electrolyte additive (ammonium cation‐based salts) to achieve long‐term and highly reversible zinc plating/stripping. Specifically, the cation can homogenize the zinc deposition via the charge shielding effect and inhibit by‐product formation by participating in the constitution of contact ion pairs. In such a way, the Zn||Zn symmetric cell stably cycles over 2145 h at a current density of 1 mA cm−2 with the overpotential of merely 25 mV. In addition, the reversibility of energy storage devices based on manganese dioxide and an activated carbon cathode is effectively enhanced. This strategy provides a promising approach for the future development of advanced aqueous metal batteries. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries are emerging as a promising candidate for large‐scale energy storage, while the short lifetime and poor reversibility of Zn anodes limit their further development. When attempting to enhance reversibility, most reported methods involve toxic and pollutive substances and decreased water content, which inevitably sacrificed safety level, rate performance, and environmentally benign characteristics. Herein, a series of low‐cost and "green" molecules are introduced into the aqueous (ZnCl2, ZnSO4) electrolytes, featured with cations coordination capability, which can significantly inhibit the hydration step of Zn2+ and delay the formation of the key by‐products (Zn5(OH)8Cl2·H2O, 3Zn(OH)3·ZnSO4·5H2O) in aqueous electrolytes via regulating the coordination status of Zn2+. In the optimized electrolyte system, a highly reversible Zn metal anode presents excellent electrochemical performance, featured with a long lifespan over 1185 h at 1 mA cm−2 and smooth deposition morphology. Furthermore, Zn–MnO2 batteries based on the electrolyte deliver high capacity retention of 82.9% after 200 cycles. These breakthroughs suggest that this method offers a versatile toolbox toward developing future advanced multivalent metal batteries for large‐scale energy storage. [ABSTRACT FROM AUTHOR]