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Despite aqueous electrolyte endowing batteries with the merits of safe operation, low-cost fabrication, and high ionic conductivity, water-induced corrosion, including spontaneous chemical and electrochemical hydrogen evolution corrosion, adversely affects lifespan and rate capability. There is still a lack of selection criteria for benchmarking corrosion behavior qualitatively. Through theoretical simulation, an anionic polarity index (API) tactic is proposed to resist corrosion by manipulating interfacial and solvated water concomitantly, thus realizing stable and fast Zn aqueous batteries (ZABs). As proof of concept, a low-cost zinc salt of 0.5 m zinc bis(4-hydroxybenzenesulphonate) (Zn(HBS) 2 ) with low-API anion is prioritized. Combined in situ spectroscopic and electrochemical analyses reveal that, even in a low-concentration electrolyte, the low-API anion reduces interfacial water in the inner Helmholtz plane, shielding the chemical water dissociation. Meanwhile, their entering into the solvation sheath of Zn 2+ lowers the solvent-separated ion pair, suppressing the electrochemical corrosion. The elaborated API-screened zinc salt endows fast plating kinetics of 50 mA cm -2 (119.1 mV polarization), high coulombic efficiency of 99.8%, dendrite-free cycling over 1600 h, and prolonged lifespan over 5000 cycles for the Zn-V cell. The results provide new metrics that can benchmark the success of ZABs for large-scale energy storage., (© 2025 Wiley‐VCH GmbH.)

Sulfur aqueous battery (SAB) is promising owing to its high theoretical capacity and cost competitiveness. Although decoupled electrolyte design has successfully endowed transition metal ion-SABs with customizability to achieve high energy density, its effectiveness in alkali ion-SABs remains problematic. Here, we identify for the first time an intractable phenomenon of alkali-ion-driven water migration between decoupled electrolytes through ex-situ NMR, which is recognized as the origin of the irreversible sulfur redox reactions. To address the challenge, we propose an alkali-ion-H2O-poor coordination strategy to effectively regulate water migration by incorporating low molecular polarity index (MPI) anions. In-situ Raman, synchrotron spectroscopy, and molecule dynamic simulations reveal that the repulsion of low MPI anions to water effectively disrupts the hydration patterns around the alkali cations, and thereby minimizes the concomitant water migration. The elaborated Na+-SAB achieved an ultrahigh capacity of 1634 mAh g-1 (97.7% sulfur utilization) and prolonged stability over 500 cycles. Furthermore, the versatility of alkali-ion-H2O-poor coordination strategy is further substantiated in Li+-SAB and K+-SAB batteries, boosting the scope of following SAB systems., (© 2025 Wiley‐VCH GmbH.)

Sulfur-based aqueous batteries (SABs) are regarded as promising candidates for safe, low-cost, and high-energy storage. However, the sluggish redox kinetics of polysulfides pose a significant challenge to the practical performance of SABs. Herein, we report a unique redox regulation strategy that leverages thiosulfate-mediated ligand-chain interaction to accelerate the polysulfide redox process (S 0 /S 2- ). The S 2 O 3 2- species in the electrolyte can induce the rapid reduction of polysulfide through a spontaneous chemical reaction with sulfur species, while facilitating the reversible oxidation of short-chain sulfides. Moreover, the thiosulfate redox pair (S 2 O 3 2- /S 4 O 6 2- ) within the K 2 S 2 O 3 electrolyte contributes additional capacity at higher potential (E 0 >0 V vs SHE). Consequently, the elaborate SAB delivers an unprecedented K + storage capacity of 2470 mAh g s -1 , coupled with a long cycling life exceeding 1000 cycles. Remarkably, thiosulfate-mediated SAB achieves an energy density of 616 Wh kg S+Zn -1 , surpassing both organic K-S batteries and conventional aqueous battery systems. This work elucidates the mechanism underlying the thiosulfate-mediated polysulfide redox process, thereby opening a pathway for the development of high-energy aqueous batteries., (© 2024 Wiley-VCH GmbH.)

Tellurium (Te), with its rich valence states (-2 to +6), could endow aqueous batteries with potentially high specific capacity. However, achieving complete and stable hypervalent Te 0 /Te 4+ electrochemistry in an aqueous environment poses significant challenges, owing to the sluggish reduction kinetics, easy dissolution of Te 4+ species, and a controversial energy storage mechanism. Herein, we demonstrate a crystallographic regulation strategy for robust aqueous Te redox electrochemistry. With strong hydrogen bonding, NH 4 Ac confines free water, prompting the amorphization of TeO 2 (a-TeO 2 ). In situ synchrotron characterization, spectroscopy analysis, electrochemical evaluation, and theoretical calculations reveal a specific 4 e - solid-solid transition pathway (Te to a-TeO 2 ) with accelerated diffusion and charge transfer kinetics, attributed to a closer unoccupied electron orbital to the Fermi level and a reduced water desorption energy barrier in a-TeO 2 . Impressively, the a-TeO 2 /Te redox exhibits a high reversible capacity of 834 mAh g -1 (99% of Te redox utilization), superior rate performance (644 mAh g -1 at 10 A g -1 ), and an ultralong lifespan (over 3000 cycles). These findings prove a new tactic to advance aqueous Te redox electrochemistry toward high-energy aqueous batteries., (© 2025 Wiley-VCH GmbH.)

Zinc-based aqueous batteries (ZABs) are attracting extensive attention due to the low cost, high capacity, and environmental benignity of the zinc anode. However, their application is still hindered by the undesired zinc dendrites. Despite Zn-surface modification being promising in relieving dendrites, a thick separator (i.e. glass fiber, 250-700 μm) is still required to resist the dendrite puncture, which limits volumetric energy density of battery. Here, we pivot from the traditional interphase plus extra separator categories, proposing an all-in-one ligand buffer layer (ca. 20 μm) to effectively modulate the Zn 2+ transfer and deposition behaviors proved by in situ electrochemical digital holography. Experimental characterizations and density functional theory simulations further reveal that the catechol groups in the buffer layer can accelerate the Zn 2+ reduction reaction (ZRR) through the electron-donating p-π conjugation effect, decreasing the negative charge in the coordination environment. Without extra separators, the elaborated system endows low polarization below 28.2 mV, long lifespan of 4950 h at 5 mA cm -2 in symmetric batteries, and an unprecedented volumetric energy density of 99.2 Wh L -1 based on the whole pouch cells. The concomitantly "separator-free" and "dendrite-free" conjugation effect with an accelerated ZRR process could foster the progression of metallic anodes and benefit energetic aqueous batteries., (© 2024 Wiley-VCH GmbH.)

In the literature, Zn-Mn aqueous batteries (ZMABs) confront abnormal capacity behavior, such as capacity fluctuation and diverse "unprecedented performances." Because of the electrolyte additive-induced complexes, various charge/discharge behaviors associated with different mechanisms are being reported. However, the current performance assessment remains unregulated, and only the electrode or the electrolyte is considered. The lack of a comprehensive and impartial performance evaluation protocol for ZMABs hinders forward research and commercialization. Here, a pH clue (proton-coupled reaction) to understand different mechanisms is proposed and the capacity contribution is normalized. Then, a series of performance metrics, including rated capacity (C r ) and electrolyte contribution ratio from Mn 2+ (CfM), are systematically discussed based on diverse energy storage mechanisms. The relationship between Mn (II) ↔ Mn (III) ↔ Mn (IV) conversion chemistry and protons consumption/production is well-established. Finally, the concrete design concepts of a tunable H + /Zn 2+ /Mn 2+ storage system for customized application scenarios, opening the door for the next-generation high-safety and reliable energy storage system, are proposed., (© 2023 Wiley-VCH GmbH.)

Poor thermodynamic stability and sluggish electrochemical kinetics of metallic Zn anode in aqueous solution greatly hamper its practical application. To solve such problems, to date, various zincophilic surface modification strategies are developed, which can facilitate reversible Zn plating/stripping behavior. However, there is still a lack of systematic and fundamental understanding regarding the metrics of thermodynamics inertia and kinetics zincophilia in selecting zincophilic sites. Herein, hetero-metallic interfaces are prioritized for the first time via optimizing different hetero metals (Fe, Co, Ni, Sn, Bi, Cu, Zn, etc.) and synthetic solvents (ethanol, ethylene glycol, n-propanol, etc.). Specifically, both theoretical simulations and experimental results suggest that this Bi@Zn interface can exhibit high efficiency owing to the thermodynamics inertia and kinetics zincophilia. A best practice for prioritizing zincophilic sites in a more practical metric is also proposed. As a proof of concept, the Bi@Zn anode delivers ultralow overpotential of ≈55 mV at a high rate of 10 mA cm -2 and stable cycle life over 4700 cycles. The elaborated "thermodynamics inertia and kinetics metalphilia" metrics for hetero-metallic interfaces can benchmark the success of other metal-based batteries., (© 2023 Wiley-VCH GmbH.)

Dendrite growth and by-products in Zn metal aqueous batteries have impeded their development as promising energy storage devices. We utilize a low-cost additive, glucose, to modulate the typical ZnSO 4 electrolyte system for improving reversible plating/stripping on Zn anode for high-performance Zn ion batteries (ZIBs). Combing experimental characterizations and theoretical calculations, we show that the glucose in ZnSO 4 aqueous environment can simultaneously modulate solvation structure of Zn 2+ and Zn anode-electrolyte interface. The electrolyte engineering can alternate one H 2 O molecule from the primary Zn 2+ -6H 2 O solvation shell and restraining side reactions due to the decomposition of active water. Concomitantly, glucose molecules are inclined to absorb on the surface of Zn anode, suppressing the random growth of Zn dendrite. As a proof of concept, a symmetric cell and Zn-MnO 2 full cell with glucose electrolyte achieve boosted stability than that with pure ZnSO 4 electrolyte., (© 2021 Wiley-VCH GmbH.)

Research interest and achievements in zinc aqueous batteries, such as alkaline Zn//Mn, Zn//Ni/Co, Zn-air batteries, and near-neutral Zn-ion and hybrid ion batteries, have surged throughout the world due to their features of low-cost and high-safety. However, practical application of Zn-based secondary batteries is plagued by restrictive energy and power densities in which an inadequate output plateau voltage and sluggish kinetics are mutually accountable. Here, a novel paradigm high-rate and high-voltage Zn-Mn hybrid aqueous battery (HAB) is constructed with an expanded electrochemical stability window over 3.4 V that is affordable. As a proof of concept, catalyzed MnO 2 /Mn 2+ electrolysis kinetics is demonstrated in the HAB via facile introduction of Ni 2+ into the electrolyte. Various techniques are employed, including in situ synchrotron X-ray powder diffraction, ex situ X-ray absorption fine structure, and electron energy loss spectroscopy, to reveal the reversible charge-storage mechanism and the origin of the boosted rate-capability. Density functional theory (DFT) calculations reveal enhanced active electron states and charge delocalization after introducing strongly electronegative Ni. Simulations of the reaction pathways confirm the enhanced catalyzed electrolysis kinetics by the facilitated charge transfer at the active O sites around Ni dopants. These findings significantly advance aqueous batteries a step closer toward practical low-cost application., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Zinc-based electrochemistry is attracting significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. However, the grid-scale application is plagued by limited output voltage and inadequate energy density when compared with more conventional Li-ion batteries. Herein, we propose a latent high-voltage MnO 2 electrolysis process in a conventional Zn-ion battery, and report a new electrolytic Zn-MnO 2 system, via enabled proton and electron dynamics, that maximizes the electrolysis process. Compared with other Zn-based electrochemical devices, this new electrolytic Zn-MnO 2 battery has a record-high output voltage of 1.95 V and an imposing gravimetric capacity of about 570 mAh g -1 , together with a record energy density of approximately 409 Wh kg -1 when both anode and cathode active materials are taken into consideration. The cost was conservatively estimated at