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Aqueous Zn‐ion batteries (AZIBs) are promising energy storage systems due to their low cost, excellent safety, and environmental friendliness. However, challenges like uncontrollable dendrite growth and side reactions during battery operation limit their commercialization. Addressing these issues requires regulating ion deposition behavior at the anode/electrolyte interface. The electrostatic shielding effect, which leverages the interplay between electric potential and ionic motion, provides a unique mechanism to inhibit zinc dendrites and side reactions effectively. Despite significant progress in understanding electrostatic shielding in AZIBs, a comprehensive summary of its effects is still lacking. This paper first reviews the primary challenges in AZIBs and then describes how the electrostatic shielding effect can optimize their performance. Existing strategies for achieving electrostatic shielding through anode structure optimization and electrolyte optimization‐are classified and analyzed. Finally, the review summarizes current electrostatic shielding strategies for stabilizing zinc anodes, identifies existing challenges, and discusses the future potential, and for this approach in AZIBs. [ABSTRACT FROM AUTHOR]

Tetrahydrofurfuryl alcohol (THFA), a cost-effective electrolyte additive, is employed innovatively to optimize both the cathode and anode, thereby enhancing the performance of zinc-based batteries significantly. [Display omitted] Aqueous zinc-ion batteries (AZIBs) are highly regarded for their affordability, stability, safety, and eco-friendliness. Nevertheless, their practical application is hindered by severe side reactions and the formation of zinc (Zn) dendrites on the Zn metal anode surface. In this study, we employ tetrahydrofuran alcohol (THFA), an efficient and cost-effective alcohol ether electrolyte, to mitigate these issues and achieve ultralong-life AZIBs. Theoretical calculations and experimental findings demonstrate that THFA acts as both a hydrogen bonding donor and acceptor, effectively anchoring H 2 O molecules through dual-site hydrogen bonding. This mechanism restricts the activity of free water molecules. Moreover, the two oxygen (O) atoms in THFA serve as dual solvation sites, enhancing the desolvation kinetics of [Zn(H 2 O) 6 ]2+ and improving the deposition dynamics of Zn2+ ions. As a result, even trace amounts of THFA significantly suppress adverse reactions and the formation of Zn dendrites, enabling highly reversible Zn metal anodes for ultralong-life AZIBs. Specifically, a Zn-based symmetric cell containing 2 % THFA achieves an ultralong cycle life of 8,800 h at 0.5 mA cm−2/0.5 mAh cm−2, while a Zn//VO 2 full cell containing 2 % THFA maintains a remarkable 80.03 % capacity retention rate at 5 A g−1 over 2,000 cycles. This study presents a practical strategy to develop dendrite-free, cost-effective, and highly efficient aqueous energy storage systems by leveraging alcohol ether compounds with dual-site hydrogen bonding capabilities. [ABSTRACT FROM AUTHOR]

The drawbacks of poor electronic conductivity and structural instability during the cycling process limit the electrochemical property of vanadium‐based cathode materials for aqueous zinc‐ion batteries. In addition, continuous growth and accumulation of zinc dendrites can puncture the separator and cause an internal short circuit in the battery. In this work, a unique multidimensional nanocomposite is designed by a facile freeze‐drying method with subsequent calcination, consisting of V2O3 nanosheets and single‐walled carbon nanohorns (SWCNHs) crosslinked together and wrapped by reduced graphene oxide (rGO). The multidimensional structure can largely enhance the structural stability and electronic conductivity of the electrode material. Besides, additive Na2SO4 in the ZnSO4 aqueous electrolyte not only prevents the dissolution of cathode materials but also suppresses the Zn dendrite growth. After considering the influence of additive concentration on ionic conductivity and electrostatic force for electrolyte, V2O3@SWCNHs@rGO electrode delivers a high initial discharge capacity of 422 mAh g−1 at 0.2 A g−1 and a high discharge capacity of 283 mAh g−1 after 1000 cycles at 5 A g−1 in 2 m ZnSO4 + 2 m Na2SO4 electrolyte. Experimental techniques reveal that the electrochemical reaction mechanism can be expressed as the reversible phase transformation between V2O5 and V2O3 with Zn3(VO4)2. [ABSTRACT FROM AUTHOR]

Despite the substantial progress in cathode materials in the past few years, rechargeable zinc batteries (RZBs) are plagued by rapid performance degradation due to dendrite formation and notorious side reactions at the Zn anode side. Here, an optimized hydrated eutectic electrolyte (HEE) system containing methylsulfonylmethane, zinc perchlorate, and water, in which an organic ligand coordinated the solvation shell of Zn ions with water molecules constituting the eutectic network, is proposed. Compared to common aqueous solutions, this HEE system is proven effective in promoting the smooth Zn deposition and plating/stripping reversibility as well as suppressing side reactions. The vanadium‐based zinc batteries based on this new HEE exhibit exceptionally high‐capacity retention (≈100% retention even after 1600 cycles at a relatively small current density of 1000 mA g−1). This study offers a new type of electrolyte for RZBs and a deep understanding of the effect of Zn2+ solvent sheath structure on the cycle reversibility. [ABSTRACT FROM AUTHOR]

• Aqueous rechargeable batteries with low-cost hybrid electrolytes can effectively improve the output voltage and alleviate the zinc dendrites. • The full cells assembled with potassium zinc hexacyanoferrate (KZnHCF) cathodes and zinc foil anodes reach an output voltage of 1.92 V and an energy density of 107.6 Wh kg−1. • The hybrid electrolyte contributes to the uniform deposition/stripping and suppress the zinc dendrites. The energy density of aqueous reachable batteries (ARBs) is limited by the output voltage in the aqueous electrolyte. Herein, low-cost aqueous hybrid electrolytes composed of ZnSO 4 and K 2 SO 4 dual salts effectively improve the output voltage and suppress the zinc dendrites. The aqueous full cells assembled with potassium zinc hexacyanoferrate (KZnHCF) cathodes and zinc foil anodes reach an output voltage of 1.92 V and an energy density of 107.6 Wh kg−1. It is demonstrated the reversible insertion/extraction of K+ at the cathodes and uniform zinc deposition/striping at the anode in hybrid electrolyte via a series in-situ and ex-situ investigation. The dual salt electrolyte can not only satisfy the reversible capacitive dominated process at the cathodes but also suppress the zinc dendrite. Density functional theory (DFT) calculation demonstrates the K+ preferential intercalation mechanism of KZnHCF in hybrid electrolyte and the inhibition effect of K+ insertion on Zn2+ insertion. This strategy presents a promising approach for development of high performance and low-cost aqueous electrolyte. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐ion batteries (ZIBs) are always regarded as a promising energy storage device owing to their higher safety and durability. However, two problems have become the main trouble for the practical application of ZIBs such as the dendrite growth of Zn metal anode in electrolyte and the freezing of water solvent at low temperature. Herein, to overcome these challenges, a new strategy, multi‐component crosslinked hydrogel electrolyte, is proposed to inhibit Zn dendrites and realize low temperature environmental adaptability for ZIBs. Benefitting from the superior inhibition effect of the polyacrylamide and dimethyl sulfoxide (DMSO) on Zn dendrites, the coulombic efficiency of the symmetric cell of ≈99.5% is achieved during the Zn plating/stripping over 1 300 h, and the assembled full‐cell demonstrates the large specific capacity of 265.2 mAh g‐1 and high cyclic stability with the capacity retention of 95.27% after 3 000 cycles. In addition, the full‐cell delivers stable operation at a wide temperature range, from 60 to −40 °C, due to the introduction of additive DMSO. This work provides an inspired strategy and novel opportunities to realize a dendrite‐free and wide‐temperature rechargeable aqueous Zn‐ion energy storage system. [ABSTRACT FROM AUTHOR]

Practical application of aqueous Zn‐ion batteries (AZIBs) is significantly limited by poor reversibility of the Zn anode. This is because of 1) dendrite growth, and 2) water‐induced parasitic reactions including hydrogen evolution, during cycling. Here for the first time an elegantly simple method is reported that introduces ethylene diamine tetraacetic acid tetrasodium salt (Na4EDTA) to a ZnSO4 electrolyte. This is shown to concomitantly suppress dendritic Zn deposition and H2 evolution. Findings confirm that EDTA anions are adsorbed on the Zn surface and dominate active sites for H2 generation and inhibit water electrolysis. Additionally, adsorbed EDTA promotes desolvation of Zn(H2O)62+ by removing H2O molecules from the solvation sheath of Zn2+. Side reactions and dendrite growth are therefore suppressed by using the additive. A high Zn reversibility with Coulombic efficiency (CE) of 99.5% and long lifespan of 2500 cycles at 5 mAh cm−2, 2 mAh cm−2 is demonstrated. Additionally, the highly reversible Zn electrode significantly boosts overall performance of VO2//Zn full‐cells. These findings are expected to be of immediate benefit to a range of researchers in using dual‐function additives to suppress Zn dendrite and parasitic reactions for electrochemistry and energy storage applications. [ABSTRACT FROM AUTHOR]

Zinc-ion batteries, known for safety and efficiency, are a hotspot in electrochemical energy storage field. Nonetheless, the emergence of dendrites on zinc anodes during electrochemical cycles can lead to capacity attenuation and even failure, particularly under low temperatures. In this study, we develop a novel dendrite-free and low-temperature resistant Zn(ClO 4) 2 /Li 2 SO 4 /Dimethyl sulfoxide (DMSO) hybrid electrolyte by using DMSO as a hydrogen bond acceptor and solvation regulator. Our research demonstrates that, by reducing the desolvation energy barrier of the Zn2+ solvation sheath and the nucleation overpotential of Zn deposition, DMSO effectively inhibits zinc dendrites and side reactions. Furthermore, DMSO disrupts hydrogen bonding between water molecules, preventing electrolyte freezing at low temperatures. As a result, at 0.5 mA cm−2, the Zn||Zn symmetric device using this hybrid electrolyte exhibits consistent operation for over 4000 h even at -25 °C, featuring a minimal deposition/dissolution overpotential of approximately 0.045 mV. Additionally, at -20 °C, the Zn||Zn(ClO 4) 2 -Li 2 SO 4 -DMSO||LiFePO 4 battery demonstrates stable cycling for over 600 cycles at 0.6 C (1 C = 170 mA g − 1), delivering a capacity of 103 mA h g−1. [ABSTRACT FROM AUTHOR]

Aqueous Zn-based batteries (AZBs) have attracted great attention due to their high safety, low cost, and environmental friendliness. However, the Zn anode suffers from problems such as the formation of Zn dendrites. And there are only few active cathode materials which can allow the insertion/extraction of Zn2+ ions. Thereinto, Prussian blue analogs (PBAs) are promising active cathode materials for AZBs, having high operation voltage but poor electrochemical stability. Herein, K 2 Zn 3 [Fe(CN) 6 ] 2 (KZnHCF) particles with cubic morphology are prepared for AZBs, and the electrochemical stability is improved by simply adjusting the composition of the electrolyte solvent in the battery system. Electrochemical tests indicate that the electrolyte with ethanol (EA) as solvent can promote the uniform deposition of zinc, thereby inhibiting the growth of Zn dendrites. Furthermore, ex-situ XRD results prove that the structural damage of KZnHCF during charging-discharge process is greatly alleviated when EA is used as the electrolyte solvent. Nonetheless, using pure EA as electrolyte solvent exposes the batteries to potential safety hazards, and compared with the Zn/KZnHCF batteries with H 2 O as solvent, the specific capacities of the batteries with EA as solvent are lower. Hence, the mixed electrolytes with different volume ratios (H 2 O/EA-1:1, H 2 O/EA-1:2, H 2 O/EA-2:1) are applied. It's obvious that not only the growth of zinc dendrites is suppressed, but also the electrochemical performances of the batteries are further improved. Overall, a dendrite-free and high-performance Zn/KZnHCF battery is obtained by using a mixed electrolyte solvent (H 2 O/EA-1:1), presenting average specific capacities of 50.0, 49.0, 46.3, and 43.2 mAh g−1 at current densities of 50, 100, 150, and 200 mA g−1, and remaining a specific capacity of 29.1 mAh g−1 at a current density of 200 mA g−1 after 500 cycles. • A dendrite-free and high-performance Zn/KZnHCF battery is created. • The inhibition effect of ethanol on the growth of Zn dendrites is clarified. • The effect of different electrolyte solvents is investigated by ex-situ XRD tests. • As-prepared Zn/KZnHCF batteries are superior to the reported aqueous zinc batteries. [ABSTRACT FROM AUTHOR]

Zinc anode is promising for various aqueous batteries due to its low cost and high theoretical specific capacity. However, poor cycling stability caused by dendritic growth seriously hampered its widespread application. Herein, we demonstrate that by using an anion-exchange membrane, quaternary ammonia poly (N -methyl-piperidine- co - p -terphenyl) (QAPPT), as the separator, the damage from short circuits can be completely prevented. More details reveal that when approaching the QAPPT membrane, Zn dendrites perform a bending growth rather than pierce through it, which helps achieve a superior cycling stability without any short. The bending growth can be ascribed to a variation of electrolyte concentration at the electrode/membrane interface where Zn electrodeposited at a very low rate in the direction perpendicular to the membrane. By using QAPPT membrane, an ultra-stable Ni–Zn full cell is then realized. This finding may pave a facile way to solve the problems associated with dendrites for diverse alkaline Zn-based batteries. Image 1 • A highly base-stable anion-exchange membrane was employed as battery separator. • The separator exhibits zincate ion-conducting property. • The unique electrode/electrolyte interface prevents the short caused by dendrites. • Providing a practical strategy for rechargeable alkaline Zn-based batteries. [ABSTRACT FROM AUTHOR]