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Aqueous zinc (Zn) based batteries show great promise as energy storage devices, cost‐effectiveness, and intrinsic safety. However, the development of Zn‐based batteries faces significant challenges, primarily stemming from poor electrochemical reversibility caused by dendrite growth, hydrogen generation, and byproduct formation on the Zn anode. In this study, valine (Val) is investigated as an electrolyte additive to finely tune the interface microenvironment, resulting in enhanced electrochemical stability of the Zn anode across a wide pH range, marking the first time such an approach has been explored. Val ions preferably adsorb onto the active sites of the Zn anode surface, enabling efficient isolation of water and SO42− from the desolvated shell layer and thus effectively inhibiting dendrite growth. The Zn||Zn symmetric cells are demonstrated with Val electrolyte additives present a remarkable cycling performance of 5400 h. Furthermore, Zn||MnO2 full cells exhibit stable operation for 5000 cycles at 3 A g−1. Notably, the Val additive also functions effectively in rechargeable alkaline cells, enabling the alkaline symmetric cells and Zn||Ni0.8Co0.1Mn0.1O2 full cells to operate durably across a wide temperature range. This work offers unique insights into electrolyte engineering for aqueous rechargeable batteries, especially in terms of their compatibility with a wide pH range. [ABSTRACT FROM AUTHOR]

Transition metal sulfides are emerging as promising anode materials for sodium‐ion batteries (SIBs) due to their high theoretical capacity and low cost, their practical application yet face critical issues of sluggish kinetics and poor cycling stability. In this study, a reliable approach is introduced to overcome these challenges by fabrication of Se0.75‐Fe1‐xS0.25@SC hollow nanospheres thanks to the enriched robust Fe─S─C, C─S, and C─Se bonding, which greatly benefit for enhancing both reaction kinetics and structural stability. Kinetic study combining with in situ characterization reveals that the incorporation of rich‐Se into FeSx induces the formation of cationic Fe and Se vacancies, leading to abundant sites and optimized path for sodium storage. Density functional theory calculations also demonstrate how Se‐rich engineering weakens carbonaceous polar C─S─Fe bonds and accelerates reaction dynamics. The as‐prepared Se0.75‐Fe1‐xS0.25@SC can deliver a high reversible capacity of 515 mAh g−1 at 2 A g−1 over 1250 cycles and achieve superior rate capability with maintaining capacity of 418 mAh g−1 at 10 A g−1. This work pioneers the concept of vacancy‐rich functionalized nanostructures, offering a new pathway for designing advanced electrode materials for energy storage devices. [ABSTRACT FROM AUTHOR]