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With the increasing safety concerns and consensus on sustainability, aqueous zinc‐ion batteries (AZIBs) are gaining significant attention as a green and efficient alternative for energy storage technologies. However, the prolonged and persistent chemical dissolution and electrochemical capacity fading of one of the dominant vanadium oxide cathodes has long posed an unavoidable challenge. Meanwhile, the energy storage mechanism of AZIBs remains controversial, along with the formation of parasitic and derived cathode‐related products during the repeated charge/discharge procedure. Herein, this review expects to provide a comprehensive analysis of the fundamental redox reactions in vanadium oxide‐based AZIBs, with particular emphasis on nanostructure features and their evolution, ionic transference, and ionic occupation, to elucidate the underlying mechanisms involved in the system. Furthermore, several effective strategies, including cathode modification and electrolyte design are summarized. Finally, the review offers potential avenues for advancing cathode materials, inorganic colloids, high‐entropy electrolytes, and mechanism characterization, thereby contributing to the continued development of this field. [ABSTRACT FROM AUTHOR]

Vanadium‐based aqueous zinc‐ion batteries (AZIBs) exhibit significant potential for large‐scale energy storage applications, attributed to their inherent safety characteristics. Addressing the slow transport kinetics of divalent Zn2+ within the cathode lattice, thereby enhancing the rate capability and stability, is essential for the Zn‐V battery system. In this study, a local electric field (LEF) strategy is introduced to accelerate the Zn2+ diffusion by creating abundant oxygen vacancies (Ov) in V2O5. Comprehensive characterization and density functional theory (DFT) calculations reveal the formation of the Ov induced atomic‐level donor‐acceptor couple configuration, verify and visualize the LEF. The fabricated LEF‐enhanced vanadium oxide (LEF‐VO) exhibits exceptional rate capability, achieving 338.3 mA h g−1 at a current density of 10 A g−1, and maintaining 66.4% of its capacity over a range from 0.2 to 20 A g−1. Furthermore, the influence of the LEF on expediting Zn2+ diffusion kinetics is elucidated, correlating to the electrical force. This novel LEF approach offers valuable insights for advancing high‐rate cathode materials. [ABSTRACT FROM AUTHOR]

Suppressing the water activity is challenging to achieve high‐performing aqueous zinc ion batteries (AZIBs), especially for its practical climate adaptability. Reconstructing the H‐bond network and repealing the solvation water can effectively reinforce the covalency inside water molecular. Here, a hydrogel electrolyte formula utilizing ClO4− anions and hydrophilic ─NH2 on polyacrylamide chains is shown to bond with water molecules, while the zincophilic glucose preferentially regulate Zn2+ solvation. The multifunctional hydrogel structure can effectively disrupt the intrinsic H‐bond network and inhibit the interface side‐reactions induced by active water. Finally, the delayed freezing point and expanded voltage stability window are realized, which promotes the ZIBs steady operate in a wide temperature range. When operating at 70 and −30 ˚C, the Zn//NVO battery achieves high specific capacity of 488 and 254 mAh g−1, respectively, surpassing most of the previously reported results. Remarkably, the pouch battery delivers the state‐of‐the‐art specific capacity of 438.1 mAh g−1 and realizes a capacity retention of 76.3% after 400 cycles at 200 mA g−1. [ABSTRACT FROM AUTHOR]

Zn interfacial issues involved dendrite evolution and undesired parasitic reactions are tough challenges to impede the progress of Zn ion battery. Herein, dendrite‐free Zn anode with boosted stability is achieved by four‐in‐one functional additive triethyl phosphate (TEP). Experiments and theoretical calculation reveal that TEP additive participates in the generation of compact inorganic interface to prevent Zn from corrosion. Meanwhile, the interfacial electrical double layer (EDL) is reconstructed with adsorbed TEP molecules in inner layer and weakened Zn2+ solvation structure in diffusion layer, which efficiently shields Zn from active H2O and moderate electrochemical kinetics, thereby preventing water‐related secondary reaction and Zn electroplating on tip region. Additionally, TEP additive manipulates zinc growth direction by adsorbing on the (002) facet, thus enabling long‐lasting dendrite‐free deposition. Accordingly, Zn||Zn symmetric cell demonstrates an ultralong lifespan over 5000 h (almost 7 months) at 1 mA cm−2, 1 mAh cm−2 and remarkable coulombic efficiency (CE) of ≈97.6% for 1500 cycles. For practical demonstration, Zn||LiFePO4 full cell demonstrates an improved rate capability and an elevated capacity of 116.0 mAh g−1. These findings highlight interface chemistry manipulated by multifunctional additives as an efficient approach to stabilize Zn anode, holding promise for top‐notch Zn‐based batteries with improved longevity. [ABSTRACT FROM AUTHOR]

Small molecule organic materials have been considered promising candidates as cathodes in aqueous zinc‐ion batteries (AZIBs) because of their low cost, environmental friendliness, and sustainable production. However, the rapid capacity fading and sluggish kinetics restrict their practical applications, especially under extremely low temperatures (−50 °C). Here, by the condensation of hexaketocyclohexane octahydrate (HKCO) and 1, 2‐diaminoanthraquinone (DQ), a fully conjugated organic molecule, anthraquinone‐quinoxaline derivative (HATAN) is prepared. With the fully conjugated structure, HATAN possesses enhanced π‐electron delocalization and strong intermolecular interaction, which ensure superior electronic conductivity and physicochemical/electrochemical stability. Additionally, the introduction of multiple redox‐active sites (C═O and C═N) can increase the theoretical capacity of HATAN. Consequently, the HATAN cathode for AZIBs exhibits remarkable capacity, long lifespan, and high‐rate capability. Even at −50  C, an exceptional capacity of 75.4 mAh g−1 and 98% capacity retention over 1500 cycles can be preserved. This study presents valuable insights into the structure design of small molecule organic cathodes for advanced AZIBs which can efficiently operate at −50 °C. [ABSTRACT FROM AUTHOR]

Low‐cost, high‐voltage‐platform, and high‐capacity MnO2 is the most promising cathode candidate for developing high‐energy‐density aqueous zinc‐ion batteries. However, the Buckets effect of runaway phase transition and irreversible dissolution restricts the electrochemical performance of MnO2. To address this issue, this report presents a bottom‐up targeted assembly concept driven by Gibbs free energy for the design of a robust Ni‐MnO2‐xFx host via Ni2+ pre‐intercalation coupled with fluorine doping. The Gibbs free energy of the host is regulated by the coordination of interlayer reinforcement and interfacial defect repair, which prevents the "layer‐to‐spinel" transition and inhibits dissolution during long‐term cycling. As expected, this cathode provides superior H+/Zn2+ storage performance across a wide temperature range. A capacity of 180.4 mAh g−1 is retained after 1000 cycles at 2 A g−1, a high specific capacity of 293.9 mAh g−1 is retained after 250 cycles at 50 °C and 2 A g−1, and a capacity of 144.5 mAh g−1 is retained after 3000 cycles at 0 °C and 0.5 A g−1. This work provides new insights into the design of stable aqueous battery‐compatible hosts for aqueous zinc‐ion batteries as well as other battery chemistries. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐δ‐MnO2 batteries, featuring high safety, high theoretical capacity, and low cost, have emerged as promising candidates for grid‐scale energy storage systems. Nevertheless, the severe cathodic structural degradation greatly hinders its further commercial application. Herein, a facile coupling engineering strategy, employing the Ti3C2Tx MXene skeleton coupled with electrolyte additive K2SO4 to reinforce the structural stability of the δ‐MnO2 cathode is proposed. Notably, the designed K‐birnessite δ‐MnO2/Ti3C2Tx composite cathode (KMO/Ti3C2) coupled with K2SO4 electrolyte additive exhibits unique electrode/electrolyte synergistic effects on inhibiting the cathodic structural collapse and promoting the Mn2+ electrodeposition. Meanwhile, the plating/stripping reversibility of the Zn anode is considerably improved by manipulating the formation of zinc dendrites. Consequently, the Zn//KMO/Ti3C2 battery achieves the remarkable specific capacity of 502.2 mAh g−1 at 0.3 A g−1 and 371.1 mAh g−1 at 2.0 A g−1. Furthermore, after 9500 cycles at a high current density of 10 A g−1, the capacity retention reaches 93.3%. Besides, the dendrite‐free Zn anode delivers excellent cycling stability (over 4800 h at 0.2 mA cm−2) and high coulombic efficiency (99.9% after 2300 cycles). The synergistic effect of electrode/electrolyte provides distinctive insights into the structural stabilization of the manganese‐based cathode to improve the overall performance of batteries. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) comprising zinc anodes hold intrinsic safety and high energy density ideally for distributed and large‐scale energy storage, thus have generated intriguing properties and increasing research interests. Unlike organic batteries, AZIBs require different, sometimes even opposite design principles and preparation strategies in solvent, electrolyte, and separator. This is especially true for the polymer materials that are widely used as critical components in stabilizing metal anodes and functioning as high‐performance safe cathode materials. This review discusses the explicit compositional and structural requisite of polymeric components in AZIBs, with an emphasis on the exclusive molecular structure–property relationship that governs the stability, reversibility, and capacity of these devices. The usage of polymers is classified into five categories aligning with the primary architecture of AZIBs: separators, additives, hydrogel electrolytes, coatings, and electrode materials. The most recent advances in the structure/property interplay of polymers by novel synthesis and preparation techniques targeting stable AZIBs are summarized and discussed. The challenges and perspectives of multifunctional polymers in developing high‐performance AZIBs are also proposed. [ABSTRACT FROM AUTHOR]

Manganese oxide is among the most promising cathode materials for rechargeable aqueous zinc‐ion batteries due to its abundant reserves, low toxicity, and high theoretical capacity. However, the occurrence of Mn dissolution and structural collapse during the charge and discharge process, as well as the hydrogen evolution reaction, zinc dendrite formation, and corrosion on the anode surface, have seriously hindered practical applications. Here, a novel cathode material design is proposed intended to enhance both cathode and anode stability simultaneously. Specifically, an inherently stable CuMn2O4 is employed as cathode material, which demonstrates good maintenance of its spinel structure during cycling. Interestingly, insertion of Zn2+‐ions leads to the extraction of Cu2+‐ions from CuMn2O4, subsequently in situ reduces to Cu0, which results in extra capacity and improves electrical conductivity. The migration of Cu2+ ions into the Zn anode surface during the charge process eventuated the formation of copper–zinc alloys via electrodeposition. Moreover, the reconstructed anode exhibits superior stability and corrosion resistance during the Zn plating‐stripping process. Consequently, the CuMn2O4 electrode demonstrates a markedly improved cycle capability compared to the spinel Mn3O4 electrode. This study highlights an unconventional copper electrochemistry in aqueous Zn‐Mn batteries and introduces a new design principle for high‐performance aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Zinc‐based batteries offer good volumetric energy densities and are compatible with environmentally friendly aqueous electrolytes. Zinc‐ion batteries (ZIBs) rely on a lithium‐ion‐like Zn2+‐shuttle, which enables higher roundtrip efficiencies and better cycle life than zinc‐air batteries. Manganese‐oxide cathodes in near‐neutral zinc sulfate electrolytes are the most prominent candidates for ZIBs. Zn2+‐insertion, H+‐insertion, and Mn2+‐dissolution are proposed to contribute to the charge‐storage mechanism. During discharge and charge, two distinct phases are observed. Notably, the pH‐driven precipitation of zinc‐sulfate‐hydroxide is detected during the second discharge phase. However, a complete and consistent understanding of the two‐phase mechanism of these ZIBs is still missing. This paper presents a continuum full cell model supported by density functional theory (DFT) calculations to investigate the implications of these observations. The complex‐formation reactions of near‐neutral aqueous electrolytes are integrated into the battery model and, in combination with the DFT calculations, draw a consistent picture of the cycling mechanism. The interplay between electrolyte pH and reaction mechanisms is investigated at the manganese‐oxide cathodes and the dominant charge‐storage mechanism is identified. The model is validated with electrochemical cycling data, cyclic voltammograms, and in situ pH measurements. This allows to analyze the influence of cell design and electrolyte composition on cycling and optimize the battery performance. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries have been identified as a viable option for grid energy storage. However, their practical application is limited by the poor performances at a high use rate of zinc. A suitable strategy to improve the cycling stability at a high depth of discharge (DOD) is by realizing the (002)‐textured Zn plating to suppress dendrite growth and side reactions. Herein, a novel electrolyte additive sodium 3‐mercapto‐1‐propanesulfonate (MPS) is introduced to regulate the zinc/electrolyte interfacial structure. The MPS anions can form an adsorption layer on the anode surface, which induces Zn deposition in the (002) direction as indicated by first‐principles calculations. Additionally, the adsorption layer can facilitate the reduction of the energy barrier associated with zinc deposition. This modified interface effectively inhibits dendrite and side reactions, resulting in a remarkable cycling lifespan for Zn||Zn symmetric cells, exceeding 800 h at a high DOD of 50%, and over 4500 h at 1.0 mA cm−2/1.0 mAh cm−2. Moreover, the capacity stability of the full cells with V2O5·H2O or polyaniline cathodes is substantially improved. A pouch‐type Zn||V2O5·H2O full cell reveals a high capacity of 42 mAh and good capacity retention of 86.6% after 250 cycles, highlighting significant potential for practical applications. [ABSTRACT FROM AUTHOR]

Reversibility, usually evaluated by Coulombic efficiency (CE) and limited by dendrite growth, has become the major roadblock toward the widespread commercialization of zincion batteries. Tailoring the Zn deposition behavior is vital to prevent dendrite growth. In this work, the facet‐terminator serine is introduced to modulate the interface and obstruct the rampant growth of the Zn (100) plane. The serine cation (Ser+) is revealed to preferentially adsorb onto the electrode/electrolyte interface, suppressing the interfacial parasitic reaction. Theoretical analysis and postmortem/operando experimental techniques indicate that the Ser+ bestows (100)‐dominated morphology to zinc anodes, enabling a highly reversible and dendrite‐free Zn anode. These features endow the Zn anode with a long cyclic life of more than 800 h for Zn//Zn batteries and a high average Coulombic efficiency of 99.8% at 5 mA cm−2 and 5 mAh cm−2 for Zn//Cu batteries. When assembling with commercial V2O5, the full battery delivers a high capacity of 345.1 mAh g−1 at 5 A g−1 with a retention of 74.1% over 2000 cycles. [ABSTRACT FROM AUTHOR]

For the development of aqueous zinc‐ion batteries, exploiting vanadium‐based cathode materials with quick kinetics and acceptable cycling stability is crucial. Herein, to achieve these goals, transition metal ions (Zn2+) and organic ions (C5H14ON+ and Ch+) are introduced into layered hydrated V2O5. The intrinsic high conductivity of Ch+ and the oxygen vacancies generated through ion pre‐intercalation accelerate the electrical mobility by optimizing the electronic structure. The Zn2+ stabilizes the layered structure and the expanded interlayer spacing improves the ionic diffusivity. The synergistic effect of pre‐intercalated Zn2+ and Ch+ results in the (Zn0.1, Ch0.1)V2O4.92·0.56H2O cathode exhibiting a discharge capacity of 473 mAh g−1 at 0.1 A g−1 with a high energy efficiency of 88% and excellent cycling stability with 91% retention after 2000 cycles at 4 A g−1. Ex situ characterizations and density functional theory calculations reveal a reversible intercalation mechanism of Zn2+, and the improved electrochemical kinetics are attributed to the altered electronic conductivity and the reduced binding energy between Zn2+ and host O2−. [ABSTRACT FROM AUTHOR]

The poor reversibility of Zn metal anodes arising from water‐induced parasitic reactions poses a significant challenge to the practical applications of aqueous zinc‐ion batteries (AZIBs). Herein, a novel quasi‐solid‐state "water‐in‐swelling‐clay" electrolyte (WiSCE) containing zinc sulfate and swelling clay, bentonite (BT), is designed to enable highly reversible Zn metal anodes. AZIB full cells based on the WiSCE exhibit excellent cyclic stability at various current densities, long shelf life, low self‐discharge rate, and outstanding high‐temperature adaptability. Particularly, the capacity of WiSCE‐based AZIB full cells retains 90.47% after 200 cycles at 0.1 A g−1, 96.64% after 2000 cycles at 1 A g−1, and 88.29% after 5000 cycles at 3 A g−1. Detailed density functional theory calculations show that strong hydrogen bonds are formed between BT and water molecules in the WiSCE. Thus, water molecules are strongly confined by BT, particularly within the interlayers, which significantly inhibits water‐induced parasitic reactions and greatly improves cyclic stability. Compared to the state‐of‐the‐art "water‐in‐salt" electrolytes, the WiSCE can provide a significantly higher capacity at the full‐cell level with a substantially reduced cost, which is promising for the design of next‐generation high‐performance AZIBs. This work provides a new direction for developing cost‐competitive AZIBs as alternatives to grid‐scale energy storage. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) may have applications in macroscale energy storage on account of their advantages of high‐safety, cost‐effectiveness, and ecofriendliness. As a promising application, flexible quasi‐solid‐state AZIBs (FQAZIBs) can withstand mechanical deformation, and can act as favorable power supply devices for wearable electronics. As FQAZIBs are one of the most exciting and rapidly ongoing topics among aqueous batteries, it is critical yet timely to summarize the latest development in this field, providing the much‐needed guidance for the fabrication of FQAZIBs. In this review, the recent progress and rational design strategies for FQAZIBs from mechanisms, design principles, and applications are systematically presented. First, the energy storage and flexible mechanisms of FQAZIBs are illuminated in detail. Subsequently, the design philosophies of FQAZIBs are also systematically elucidated. Moreover, the latest progress and practical applications of FQAZIBs in wearable electronics are reviewed in detail according to various functions such as compressibility, stretchability, electrochromic ability, anti‐freezing ability, self‐healing ability, self‐charging properties, photodetecting function, shape memory, biodegradability, and actuated function. Finally, some applications and promising prospects in the research area of FQAZIBs are demonstrated to supply guidelines on the exploitation of their practical applications. [ABSTRACT FROM AUTHOR]

Metal zinc is recognized as a promising anode candidate for aqueous zinc‐ion batteries (AZIBs), however, dendrites and byproducts formation severe deteriorate its reversibility and practical lifespan. Herein, a polydopamine (PDA) layer, which offers the dual effects of fast desolvation and ion confinement, is constructed on the surface of a Zn anode for efficient AZIBs. The abundant polar functional groups in PDA significantly enhance interfacial contact in aqueous media, which reduces the number of water molecules reaching the zinc surface through fast desolvation, thus lowering the energy barrier for Zn2+ migration. Furthermore, the porous PDA coating controls the ion flux via the ion‐confinement effect, thereby accelerating Zn2+ kinetics on the zinc surface. Consequently, Zn@PDA exhibits significantly improved Zn2+ deposition kinetics (nucleation potential of only 32.6 mV vs 50.2 mV of bare Zn) compared with bare Zn at 2.0 mA cm−2, with a dendrite‐free surface and negligible byproduct formation. When paired with a MnO2 cathode, the Zn@PDA//MnO2 cell delivers high discharge capacity and long cycle stability without significant performance deterioration over 1000 cycles at 1.0 A g−1. Additionally, the cell demonstrates excellent shelving‐restoring performance. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc‐ion batteries (ZIBs) have aroused tremendous attention in energy storage system due to their high safety, eco‐friendliness, low cost, and for their good compatibility. Transition metal sulfides and selenides are considered to be promising cathodes for aqueous ZIBs owing to their unique layered structure and tunable interlayer spacing for the accelerating diffusion and reversible intercalation of hydrated Zn2+. However, their practical applications are severely impeded by some defects, such as the inferior electronic conductivity, large ion diffusion energy barrier, and bad cyclic stability. In this review, the various modification strategies including phase engineering, defect engineering, interlayer intercalation, in situ electrochemical oxidation, hybridization, doping effects, and surface modification are categorized and highlighted to improve the electrochemical properties of transition metal sulfides and selenides cathode materials, which are discussed and summarized corresponding to particular modification strategies. Finally, several key breakthrough directions such as mechanism exploration technology, electrolyte strategies, synergistic engineering, high‐capacity conversion‐type, high‐voltage cathode materials, and rocking‐chair type batteries are proposed to further push forward the development of aqueous ZIBs, to guide the design of advanced‐properties cathode materials for aqueous ZIBs. [ABSTRACT FROM AUTHOR]

The most commonly used zinc foil anode for aqueous zinc‐ion batteries suffers from poor cycle stability and low zinc utilization. Zinc‐plated anodes on the host materials with high zincophilicity and stability are receiving increasing attention to alleviate these above issues. Here, the high zinc deposition activity of Cu (2 2 0) is confirmed through experimental observations and theoretical calculations and then Cu (2 2 0) substrates are prepared with the highly preferred orientation through an industrial electrolysis strategy. The prepared Cu (2 2 0) substrate can consistently modulate dense zinc growth by inducing the Zn (0 0 1) growth with the lowest surface energy and exposing high‐index zinc facets due to its exceptional grain size, high deposition activity, and homogeneous crystal orientation, which result in the high zinc plating/stripping reversibility of this Cu (2 2 0) substrate. When assembled into the Zn//MnO2 battery, the zinc‐plated Cu (2 2 0) can deliver capacity retention of 93.9% after 640 cycles at high zinc utilization (≈20%). This scalable orientation design strategy provides a new perspective for realizing dendrite‐free metal deposition with special textures. [ABSTRACT FROM AUTHOR]

Interlayer engineering is a promising strategy to modify the structure of layered vanadium‐based oxides with optimized ion‐diffusion capability, during which the role of interlayer crystal water in tuning the charge storage properties should be clarified. Herein, a series of hydrated V2O5·nH2O xerogels with varying contents of interlayer water (n) is obtained by differentiating the temperature parameter. Results show that the value n should be properly modified to the best value that is not too large or too small, that is, when n equals 0.26, the V2O5·nH2O electrode exhibits optimized discharge capacity (456.5 mAh g−1 at 0.1 A g−1) and cycling stability with 94.3% retention after 2,000 cycles at 3 A g−1. Regulation of interlayer water content appears to weaken the electrostatic interaction between the VO framework and intercalated Zn2+, which thus enhances the reversibility of the zincation and structural evolution during cycling. Density functional theory calculations suggest that the V2O5·0.26H2O material with modulated electron structure can provide a favorable electrostatic environment for reversible Zn2+ diffusion with a lower migration barrier. The findings of this work are expected to arouse more intensive research efforts into the role of structural water in tuning the energy storage performance in various electrode materials. [ABSTRACT FROM AUTHOR]

Despite a promising outlook due to the intrinsic low cost and high safety, the practical application of aqueous Zn‐ion battery is impeded by the severe mutual problems of cathode dissolution, electrolyte parasitic reactions, and metallic anode dendrite growth. Herein, a triple‐functional strategy is proposed that a polyoxovanadate (POV) cluster of K10[VIV16VV18O82] as a promising Zn2+ host can concomitantly stabilize the cluster cathode, aqueous electrolyte, and metallic Zn anode. An in situ generated cathode electrolyte interface via anodic oxidation is identified as effective in preventing the dissolution of POV cathode. Molecular dynamics simulation and density functional theory calculation confirm that the [VIV16VV18O82]10− polyoxoanions can synergistically suppress electrolyte side reactions by modulating the primary solvation shell of Zn2+‐6H2O, and random anode dendrite growth by in situ constructing a stable solid electrolyte interface of Zn‐POV. As a result, the Zn//POV battery exhibits unprecedented cycling durability over 10 000 cycles at high rates of 5 and 12 A g−1. In a systematic consideration, the findings enlighten the origin of triple‐functional polyoxometalates and will significantly propel the practical development of aqueous batteries. [ABSTRACT FROM AUTHOR]

Aqueous zinc–ion batteries (ZIBs) have been promptly developed as a competitive and promising system for future large‐scale energy storage. In recent years, vanadium (V)‐based compounds, with diversity of valences and high electrochemical‐activity, have been widely studied as cathodes for aqueous ZIBs because of their rich reserves and high theoretical capacity. However, the stubborn issues including low conductivity and sluggish kinetics, plague their smooth application in aqueous ZIBs. Among various countermeasures, defect engineering is believed as an effective method to alleviate the above limitations. This review highlights the challenges of different V‐based cathode materials (e.g., vanadium oxides and vanadates) and summarizes the advances in defect engineering strategies including types and effects of the defects, designed strategies, and characterization techniques for high‐energy ZIBs. Finally, several sound prospects in this fervent field are also rationally proposed for fundamental research and practical application. [ABSTRACT FROM AUTHOR]

Poor interfacial stability, undesired side reactions, and sluggish reaction kinetics greatly impair the zinc storage performance of vanadium‐based cathode materials. Here, an in situ electrochemical conversion strategy is employed to synergistically deal with these issues. Through the initial electrochemically charging, the CaV4O9 cathode is reconstructed into an oxygen‐deficient navajoite V5O12−x·6H2O (HVOd) coated by gypsum (CaSO4·2H2O (GP)) layers, denoted as GP‐HVOd. The GP interphase with "desiccant" properties can not only suppress the vanadium dissolution, but also regulate the desolvation of hydrated Zn2+ through its strong hydrophilicity and space confinement, thus facilitating the interfacial kinetics with reduced activation energy. With less water molecules eroding the HVOd bulk phase, the typical water‐induced by‐products can also be eliminated. Moreover, highly reversible Zn2+ storage is guaranteed by HVOd with in situ generated oxygen defects. Under such coordination, GP‐HVOd delivers a high capacity of 402.5 mA h g−1, excellent cycling stability at 0.2 A g−1 with 99.7% capacity retention after 200 cycles, mighty rate performance, and high tolerance to sub‐zero environments (143.2 mA h g−1 retained at 3 A g−1 and −25 °C). This work provides a new opportunity to propel the development of highly efficient zinc‐storage cathodes. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries (AZIBs) are promising candidates for implementing large‐scale energy storage, but the adverse side reactions and unsatisfactory cycle life brought by Zn‐metal anodes limit their potential in applications. Herein, an ingenious synthesized CuS1–x@polyaniline (PANI) is proposed as an attractive conversion‐type Zn‐metal‐free anode for AZIBs, in which appropriate S‐vacancies and PANI heterointerfaces can be simultaneously constructed. This "killing three birds with one stone" strategy stabilizes the anode structure by utilizing organic–inorganic heterointerfaces and enhances Zn2+ storage, benefiting from abundant S‐vacancies, as well as initiating fast Zn2+ transport kinetics based on the joint effect of the two. Operando X‐ray absorption fine structure and synchrotron X‐ray diffraction further reveal the highly reversible conversion reaction of CuS1–x@PANI via a distinct crystallization–amorphous transformation mechanism. These features endow CuS1–x@PANI with sufficient zinc‐ion storage capacity (215 mA h g−1 at 100 mA g−1) and reliable current abuse tolerance (154.3 mA h g−1 at 1 A g−1 after 1000 cycles). Moreover, when matched with the optimized ZnxMnO2 cathode, the full battery achieves a record‐high cycling performance of 10 000 cycles (80% capacity retention) at a superhigh current density of 10 A g−1. This study provides new opportunities for developing high‐performance rocking‐chair AZIBs. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc‐ion batteries (AZIBs) have attracted extensive attention and are considered to be promising energy storage devices, owing to their low cost, eco‐friendliness, and high security. However, insufficient energy density has become the bottleneck for practical applications, which is greatly influenced by their cathodes and makes the exploration of high‐performance cathodes still a great challenge. This review underscores the recent advances in the rational design of advanced cathodes for AZIBs. The review starts with a brief summary and evaluation of cathode material systems, as well as the introduction of proposed storage mechanisms. Then, fundamental problems associated with ion and electron transport behaviors inside the electrode will be pointed out and followed by potential solutions, aiming to reveal the correlation between cathode architecture design and efficient transport kinetics through structural engineering. Afterward, the structural engineering for designing advanced cathodes, including interlayer intercalation, doping effects, defect engineering, surface coatings, composite formation, and morphology control, are summarized and discussed from the view of experimental and theoretical results. Finally, the critical research challenges and future perspectives on advanced cathode materials as well as the potential developing directions of AZIBs are also given. [ABSTRACT FROM AUTHOR]

Ongoing interest is focused on aqueous zinc ion batteries (ZIBs) for mass‐production energy storage systems as a result of their affordability, safety, and high energy density. Ensuring the stability of the electrode/electrolyte interface is of particular importance for prolonging the cycling ability to meet the practical requirements of rechargeable batteries. Zinc anodes exhibit poor cycle life and low coulombic efficiency, stemming from the severe dendrite growth, and irreversible byproducts such as H2 and inactive ZnO. Great efforts have recently been devoted to zinc anode protection for designing high‐performance ZIBs. However, the intrinsic origins of zinc plating/striping are poorly understood, which greatly delay its potential applications. Rather than focusing on battery metrics, this review delves deeply into the underlying science that triggers the deposition/dissolution of zinc ions. Furthermore, recent advances in modulating the zinc coordination environment, uniforming interfacial electric fields, and inducing zinc deposition are highlighted and summarized. Finally, perspectives and suggestions are provided for designing highly stable zinc anodes for the industrialization of the aqueous rechargeable ZIBs in the near future. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) have attracted considerable attention as promising next‐generation power sources because of the abundance, low cost, eco‐friendliness, and high security of Zn resources. Recently, vanadium‐based materials as cathodes in AZIBs have gained interest owing to their rich electrochemical interaction with Zn2+ and high theoretical capacity. However, existing AZIBs are still far from meeting commercial requirements. This article summarizes recent advances in the rational design of vanadium‐based materials toward AZIBs. In particular, it highlights various tactics that have been reported to increase the intercalation space, structural stability, and the diffusion ability of the guest Zn2+, as well as explores the structure‐dependent electrochemical performance and the corresponding energy storage mechanism. Furthermore, this article summarizes recent achievements in the optimization of aqueous electrolytes and Zn anodes to resolve the issues that remain with Zn anodes, including dendrite formation, passivation, corrosion, and the low coulombic efficiency of plating/stripping. The rationalization of these research findings can guide further investigations in the design of cathode/anode materials and electrolytes for next‐generation AZIBs. [ABSTRACT FROM AUTHOR]

Abstract: Rechargeable aqueous zinc‐ion batteries (ZIBs) with high safety and low‐cost are highly desirable for grid‐scale energy storage, yet the energy storage mechanisms in the current cathode materials are still complicated and unclear. Hence, several sodium vanadates with NaV3O8‐type layered structure (e.g., Na5V12O32 and HNaV6O16·4H2O) and β‐Na0.33V2O5‐type tunneled structure (e.g., Na0.76V6O15) are constructed and the storage/release behaviors of Zn2+ ions are deeply investigated in these two typical structures. It should be mentioned that the 2D layered Na5V12O32 and HNaV6O16·4H2O with more effective path for Zn2+ diffusion exhibit higher ion diffusion coefficients than that of tunneled Na0.76V6O15. As a result, Na5V12O32 delivers higher capacity than that of Na0.76V6O15, and a long‐term cyclic performance up to 2000 cycles at 4.0 A g−1 in spite of its capacity fading. This work provides a new perspective of Zn2+ storage mechanism in aqueous ZIB systems. [ABSTRACT FROM AUTHOR]