Search Results (187)

Aqueous zinc–manganese dioxide (Zn–MnO₂) batteries are undergoing a paradigm shift from traditional ion-insertion mechanisms to a reversible deposition/dissolution process. By leveraging a two-electron transfer (Mn²⁺/MnO₂), this electrolytic system achieves a high theoretical capacity of 616 mAh g⁻¹ and a theoretical operating voltage of 1.99 V. However, the accumulation of dead Mn, electrically isolated inactive phases, and dynamic interfacial pH fluctuations remain critical barriers to cycle life and practical energy density. This review systematizes a trinitarian strategy to overcome these bottlenecks, focusing on interfacial engineering, redox mediator-assisted recovery, and advanced electrode architectures. We evaluate how anion engineering and pH-buffering stabilize reaction pathways, and how diverse mediators (e.g., halogens, metal ions, and organic molecules) chemically rescue inactive manganese. Furthermore, we examine the integration of 3D carbon networks and low-cost hybrid electrodes to sustain high-areal-capacity deposition. To elucidate these complex mechanisms, we highlight multiscale analytical approaches combining synchrotron X-ray techniques and density functional theory (DFT). Finally, we outline a roadmap for applications ranging from grid-scale flow batteries to flexible wearable electronics. This work provides a comprehensive perspective on realizing sustainable, safe, and high-performance zinc-based energy storage. Full article

Aqueous zinc-ion batteries offer a safe and economical platform for large-scale energy storage, yet vanadium oxide cathodes remain hindered by sluggish Zn²⁺ migration, poor electronic conductivity, and structural degradation during cycling. Herein, a PEDOT regulated interfacial engineering strategy is proposed to construct surface modified sodium vanadium oxide nanostructures with coordinated ion and electron transport. The 1P-NaVO cathode retains the layered framework while introducing a PEDOT-derived surface component that strengthens interfacial charge transfer and preserves accessible Zn²⁺ diffusion pathways, delivering 655 mAh g⁻¹ at 0.1 A g⁻¹. Kinetic analyses further reveal accelerated charge storage behavior, including an increased pseudocapacitive contribution, a low charge transfer activation energy of 20.6 kJ mol⁻¹, and improved Zn²⁺ diffusion, with D_Zn²⁺ values of approximately 10^−10.8 to 10^−9.8 cm² s⁻¹. Ex situ XRD and SEM disclose a reversible structural response during Zn²⁺ insertion and extraction, involving interlayer perturbation, local framework relaxation, transient electrolyte-derived surface species, and partial morphology recovery after recharge. These findings show that controlled PEDOT-derived surface regulation promotes efficient coupling between interfacial electron transfer and Zn²⁺ diffusion, offering a practical design principle for durable vanadium-based cathodes in aqueous zinc-ion batteries. Full article

Aqueous zinc-ion batteries (AZIBs) are promising for grid-scale storage due to their safety, low cost, and environmental benignity. However, water-dipole enrichment in the inner Helmholtz plane (IHP) of Zn anodes triggers hydrogen evolution, corrosion, and dendrites, limiting cycle life. We report a trace “ionic liquid–polar solvent coupling” strategy: adding only 0.01 M EMIMBF₄ and 0.03 M DMSO to 2 M ZnSO₄ electrolyte. Hydrophobic EMIM⁺ adsorbs on the IHP to expel interfacial water, while BF₄⁻ enters the primary solvation shell and DMSO penetrates both first and second shells of Zn²⁺, forming a water-deficient coordination environment. This interfacial–solvation synergy suppresses parasitic reactions and directs preferentially oriented Zn deposition exclusively along the (101) facet, enabling dense vertical plating and in situ formation of a compact, inorganic-rich SEI (ZnCO₃–ZnSO₃–Zn(OH)₂). Consequently, Zn||Zn cells cycle stably for >5362 h at 1 mA cm⁻²/1 mAh cm⁻²; Zn||Cu cells achieve 1300 cycles with 99.8% average Coulombic efficiency; and Zn||V₂O₅ full cells retain 326.4 mAh g⁻¹ after 500 cycles. This work shows that minimal additive loading can simultaneously engineer the electrode–electrolyte interface and crystallographic deposition pathway, offering a simple yet robust design for ultra-stable AZIBs. Full article

Aqueous zinc-ion batteries are promising for large-scale energy storage due to their intrinsic safety, low cost, and environmental friendliness. However, their practical application is severely impeded by water-induced parasitic reactions and uncontrollable dendrite growth at the anode interface. Furthermore, the freezing of aqueous electrolytes at subzero temperature restricts their all-weather viability. Herein, we report a hydrogel electrolyte with interfacial regulation capabilities. By optimizing interfacial ion transport, the hydrogel electrolyte guides uniform Zn²⁺ deposition, effectively mitigating parasitic reactions and dendrite growth while enabling exceptional low-temperature tolerance. Consequently, the symmetric Zn//Zn cell using the hydrogel electrolyte delivers ultra-high cycling stability for 4000 h at 0.5 mA cm⁻² under −30 °C. When assembled into full cells, the Zn//NH₄V₄O₁₀ configuration operates stably for 4000 cycles at 5 A g⁻¹, exhibiting outstanding capacity retention. Furthermore, the assembled flexible pouch cell maintains 86% of initial capacity after 900 cycles at 3 A g⁻¹. Notably, the pouch cells demonstrate reliable operation and structural integrity under severe conditions, such as ice baths, bending, and piercing. This work provides an effective strategy for durable, wide-temperature, and intrinsically safe flexible aqueous energy storage systems. Full article

The development of high-performance cathode materials represents a crucial strategy for enhancing the overall electrochemical performance of aqueous alkaline zinc batteries. The rational design of electrode microstructure and chemical composition can synergistically boost the electrochemical reaction activity, ion/electron transport kinetics, and structural stability. In this work, a composite cathode material, FLG@Ni_xS₆/Co₄S₃/Ni-Co(OH)₂, was successfully synthesized via an electrochemical codeposition method. The engineered architecture offers abundant electrochemically active sites, well-defined ion diffusion pathways, and continuous electron conduction networks. Moreover, the strong interaction among the constituent phases effectively regulates and accelerates the redox reaction kinetics. When integrated into an aqueous alkaline zinc battery, the device attains a high specific capacity of 385 mAh g⁻¹ at 2 A g⁻¹, excellent rate capability (287 mAh g⁻¹ at 80 A g⁻¹), a gravimetric energy density of 590 Wh kg⁻¹, a power density of 128.57 kW kg⁻¹, and remarkable cycling stability, with 100% capacity retention maintained after 20,000 cycles. Overall, this study proposes a scalable and rational composite strategy for designing high-performance electrode materials for next-generation electrochemical energy storage systems. Full article

Aqueous zinc-ion batteries (AZIBs) are regarded as promising electrochemical energy storage devices owing to their low cost, intrinsic safety, abundant zinc reserves, and desirable specific capacity. Prussian blue analogues (PBAs) have been extensively investigated because of their inexpensive raw materials, ease of fabrication, open frameworks, and high theoretical specific capacity; however, the application of PBAs as cathode materials for aqueous zinc-ion batteries (AZIBs) is hindered by poor cycling performance and limited capacity. In this work, a small amount of manganese ions was successfully introduced into the N-coordinated metal sites of zinc hexacyanoferrate (ZnHCF) to tailor its electrochemical stability. The N-coordinated metal species in PBAs directly influence the intercalation chemistry of Zn ions. The coexistence of manganese and zinc in manganese-substituted zinc hexacyanoferrates (MZHCFs) generates a synergistic effect that suppresses Jahn–Teller distortion and cathode material dissolution, endowing MZHCFs with superior cycling performance compared with PBAs containing a single N-coordinated metal (Mn or Zn). At a Mn content of 10%, a specific discharge capacity of 100 mAh g⁻¹ is achieved at a current density of 1 A g⁻¹, and the capacity retention is optimized, showing no decay relative to the initial discharge capacity after 2000 galvanostatic cycles. This study demonstrates that substituting the N-coordinated metal in PBAs with other metal ions is an effective strategy to improve their electrochemical cycling stability and capacity. Full article

As an innovative technique in the field of energy storage, aqueous zinc-ion batteries (AZIBs) have garnered considerable research interest over recent years. However, designing and developing high-performance cathode materials for AZIBs remains a primary challenge. In this study, a novel POV-based cathode material, [KV₁₆O₃₈]₂[Zn₂(en)₅][Zn(en)₂H₂O]₄·en·12H₂O·6OH⁻ (KZVO), was first synthesized using a hydrothermal method, demonstrating a high specific capacity of 255.9 mAh g⁻¹ at 0.5 A g⁻¹ and excellent long-term cycling performance, retaining 206.5 mAh g⁻¹ after 2000 cycles at 4 A g⁻¹, with a capacity retention of 77.6%. It is noteworthy that KZVO undergoes a gradual phase transition during electrochemical cycling. At 4 A g⁻¹, the phase transformation is completed after approximately 580 cycles, and the newly formed phase remains stable during subsequent cycles. Additionally, ex situ XRD and XPS analyses were conducted to further investigate the phase evolution and Zn²⁺ storage mechanism. In summary, this work not only demonstrates the effective utilization of POV-based cathode materials but also provides a novel perspective for the design of future AZIB cathode materials. Full article

Aqueous zinc-ion batteries (AZIBs) are highly promising for large-scale energy storage applications owing to their distinct merits, such as exceptional safety, abundant zinc reserves, high ionic conductivity, and facile manufacturing. Featuring natural abundance, low cost, environmental benignity, and high theoretical specific capacity, Mn₂O₃ has emerged as one of the most competitive cathode candidates for AZIBs. However, the low electrical conductivity of Mn₂O₃ impedes electron transport within the electrode, leading to significant polarization during charging and discharging and poor rate performance. Therefore, this study focuses on Mn₂O₃, and combines it with lignin-derived N,S-co-doped carbon dots (NS-CDs). Through a composite modification strategy, efficient conductive pathways are constructed and the structure of Mn₂O₃ is stabilized simultaneously, thereby effectively enhancing the electrical conductivity of the modified cathode. The incorporation of NS-CDs improves the high-rate response of the Mn₂O₃ cathode, with the optimized composite retaining capacity stability at 5 A g⁻¹. At 0.2 A g⁻¹, the specific capacity reaches 174 mAh g⁻¹, and at a current density of 1 A g⁻¹, the material can sustain 1000 cycles. These results highlight biomass-derived carbon dots as a viable interfacial modifier for Mn-based AZIB cathodes. Full article

Spurred by the rapid expansion of renewable and clean energy technologies, secondary batteries have become indispensable to modern energy systems. At the same time, growing demand for safer and more environmentally friendly energy-storage solutions has accelerated interest in zinc-ion batteries (ZIBs), which offer attractive advantages over lithium-ion batteries, including high theoretical capacity, intrinsic safety, and natural abundance. This review summarizes recent progress in aqueous ZIBs, with particular focus on highly reversible Zn anode, electrolyte optimization, and the development of advanced cathode materials. In addition, emerging methods designed to address the key limitations of aqueous ZIB systems are discussed. Finally, this review provides perspectives on future research directions and design principles that may guide the development of next-generation aqueous ZIBs. Full article

Manganese-based cathodes offer high capacity, low cost, and safety for aqueous zinc-ion batteries (AZIBs), yet suffer from Mn dissolution, Jahn–Teller distortion, and sluggish Zn²⁺ kinetics. Herein, a Zn/Co co-doped MnO nanoporous carbon composite (denoted as ZnCo-MnO@NPC) derived from a bimetallic ZnCoMn metal–organic framework (ZnCoMn-MOF-74) is successfully synthesized and proposed as a high-performance cathode to address these challenges. The introduction of Zn²⁺ increases the initial specific capacity of MnO, while Co doping effectively suppresses the Jahn–Teller distortion and improves the integrity of the structure. Furthermore, the nanoporous carbon matrix facilitates electrolyte infiltration and accelerates ionic transport. To further suppress dendrite growth and enhance cycling stability, a zeolitic imidazolate framework (ZIF-8) protective layer is engineered on the zinc anode (denoted as ZIF-8@Zn), effectively mitigating dendrite formation. The ZnCo-MnO@NPC//ZIF-8@Zn full cell demonstrates superior electrochemical performance, delivering 281.3 mAh g⁻¹ at 0.1 A g⁻¹ and retaining 98.7% of this value after 3500 long-term cycles at 2.0 A g⁻¹, a remarkable finding that underscores its potential for high-performance energy storage. Collectively, this work highlights that transition metal ion doping represents an effective way to design efficient high-performance MOF-derived cathodes of AZIBs. Full article

As a result of the high safety, low cost, and environmental benignity, aqueous zinc-ion batteries are regarded as one of the most promising candidates for next-generation large-scale energy storage systems. However, their further development is constrained by performance bottlenecks in existing cathode materials, including capacity, cycle life, and reaction kinetics. In this study, a high-entropy design strategy is employed to synthesize the metal oxide (FeNiMnMgCuCo)₃O₄ with a cubic spinel structure, and its electrochemical performance as a cathode for zinc-ion batteries is systematically evaluated. The prepared (FeNiMnMgCuCo)₃O₄ high-entropy cathode exhibits high reversible capacity (341.3 mA h g⁻¹ at 0.1 A g⁻¹) and remarkable long-term cycling stability (76.1% retention after 1000 cycles at 3 A g⁻¹). This work not only demonstrates a high-entropy cathode material with practical potential but also provides new research insights for optimizing zinc-ion storage performance through composition design and entropy regulation. Full article

To meet the requirements of flexibility and high performance for energy storage devices in flexible wearable electronic equipment, the MnO₂/acetylene black composite flexible cathodes is fabricated via 3D printing technology and the aqueous manganese-based zinc-ion flexible batteries are assembled. Based on bending and torsion mechanical tests, and the electrochemical tests, the optimal 3D printing electrode structure was determined. The micromorphology of the electrode after mechanical tests shows that when the printed lines of the upper and lower layers form a 30° angle, the electrode sheet exhibits the least damage. Electrochemical tests indicated that it had an ohmic resistance of 2.052 Ω, an interfacial charge transfer resistance of 141.1 Ω, a specific capacity of 103 mAh/g at 50 mA/g, and a specific capacity of 65 mAh/g at 500 mA/g. Compared with traditional coated electrodes, the 3D-printed electrode showed significantly improved diffusion coefficient, conductivity, and cycle stability. The assembled 3D-printed flexible battery could stably power a 1.5 V LED bulb under flat, bent, and twisted states. It provides a feasible solution for the development of high-performance flexible energy storage devices. Full article

Aqueous zinc-ion batteries (AZIBs) are promising for large-scale grid storage due to inherent safety, low cost, environmental compatibility, high theoretical capacity (820 mAhg⁻¹), and suitable redox potential (−0.763 V vs. SHE). However, practical deployment is hindered by coupled challenges at the zinc anode–hydrogen evolution, dendrite growth, and corrosion/passivation, which severely limit cycle life and coulombic efficiency. This review systematically summarizes key advances in AZIB research. It first elucidates working principles and four cathode energy storage mechanisms: Zn²⁺ insertion/extraction, H⁺/Zn²⁺ co-insertion, chemical conversion, and dissolution/deposition. Second, it examines four mainstream cathodes (manganese-based, vanadium-based, Prussian blue analogs, and organic compounds), analyzing performance bottlenecks and corresponding optimization via structural modification. Third, it explores functional mechanisms of advanced separators (polymer, inorganic/ceramic composite, MOF-based, and cellulose-based) in regulating uniform Zn²⁺ deposition and suppressing dendrites. Fourth, it summarizes anode optimization strategies: artificial protective layers for interface stabilization, electrolyte additives to modulate Zn²⁺ solvation/deposition, and 3D porous structures to reduce local current density and provide nucleation sites. Finally, key scientific challenges and future directions are discussed—multi-strategy synergy, in situ characterization, practical battery construction, and sustainable technological development, offering theoretical guidance for advancing AZIBs toward large-scale applications. This review aims to provide a comprehensive perspective spanning from materials to systems, and from mechanisms to applications. Its core objective is not merely to list the types of cathode materials, but to establish a logical bridge directly connecting “key challenges” to “optimization strategies,” with a particular emphasis on the issues and solutions related to the cathode side. Full article

Zinc-ion batteries have garnered significant research interest owing to their inherent safety, low cost, and environmental compatibility. Nevertheless, their widespread adoption is impeded by critical challenges including uncontrollable dendrite growth, parasitic side reactions stemming from active water molecules, and the corrosion of the zinc anode in conventional aqueous electrolytes. Herein, a hydrated deep eutectic solvent (HDES) electrolyte based on ZnSO₄, MnSO₄, and ethylene is proposed for high-performance zinc-ion batteries. This electrolyte demonstrates excellent stability and simultaneously enables the formation of a protective coating on the Zn anode surface. Spectroscopic analyses and theoretical simulations reveal that this electrolyte reconfigures the primary Zn²⁺ solvation shell by replacing water molecules with HDES components. This tailored solvation structure facilitates interfacial desolvation, elevates nucleation overpotential, and promotes uniform, dendrite-free zinc deposition. Simultaneously, a robust hydrogen bond network effectively sequesters free water, significantly suppressing the hydrogen evolution reaction and anode corrosion. Benefiting from these features, the HDES-based full cell delivers exceptional long-term stability, achieving over 2000 cycles at 3 mA cm⁻² with a capacity retention exceeding 95% and a Coulombic efficiency surpassing 85%. In sharp contrast, the traditional aqueous counterpart fails within only 200 cycles. This tenfold lifespan enhancement, coupled with cost-effectiveness and non-flammability, presents a promising strategy for advanced, grid-scale zinc-based energy storage. Full article

Polymer electrolytes have been explored as an alternative to conventional aqueous electrolytes in zinc-ion batteries, particularly for flexible and wearable applications. Despite the increasing interest in polymer electrolyte-based zinc-ion batteries (ZIBs), their development is still in its early stages due to various challenges. In this study, we investigated three promising polymer electrolytes: CSAM (carboxyl methyl chitosan with acrylamide monomer), PAM (polyacrylamide monomer hydrogel electrolyte), and p-PBI (phosphate-doped polybenzimidazole solid electrolyte) with Zn(ClO₄)₂ and Zn(OTf)₂, as electrolytes for zinc-ion batteries. The p-PBI solid electrolyte showed high mechanical stability and improved resistance to short-circuiting during cycling. The presence of carboxyl groups in CSAM and the existence of O-H bonding facilitated ion movement, resulting in enhanced ionic conductivity and preventing dendrite formation. Incorporating these hydrogels with high-performance zinc salts, such as zinc triflate (Zn(OTf)₂), resulted in stable symmetric cell cycling over 4000 h with a uniform voltage profile under 1 mA/cm² and a low overpotential of around 53 mV cycling with CSAM. Rate-dependent full-cell testing showed that the PBI solid electrolyte delivers higher capacity retention at different current densities, whereas CSAM exhibits markedly better long-term stability, even at low voltages, owing to its effective dendrite suppression, which helps preserve cathode performance over extended cycling. Full article