High-performance Zinc-ion Batteries Research Articles

Ethylene Glycol-Choline Chloride Based Hydrated Deep Eutectic Electrolytes Enabled High-Performance Zinc-Ion Battery.

Aqueous rechargeable zinc-ion batteries (ARZIBs) are considered as an emerging energy storage technology owing to their low cost, inherent safety, and reasonable energy density. However, significant challenges associated with electrodes, and aqueous electrolytes restrict their rapid development. Herein, ethylene glycol-choline chloride (Eg-ChCl) based hydrated deep-eutectic electrolytes (HDEEs) are proposed for RZIBs. Also, a novel V10O24·nH2O@rGO composite is prepared and investigated in combination with HDEEs. The formulated HDEEs, particularly the composition of 1ml of EG, 0.5g of ChCl, 4ml of H2O, and 2M ZnTFS (1-0.5-4-2 HDEE), not only exhibit the lowest viscosity, highest Zn2+ conductivity (20.38mScm-1), and the highest zinc (Zn) transference number (t+ = 0.937), but also provide a wide electrochemical stability window (>3.2V vs ZnǁZn2+) and enabledendrite-free Zn stripping/plating cycling over 1000 hours. The resulting ZnǁV10O24·nH2O@rGO cellwith 1-0.5-4-2 HDEE manifests high reversible capacity of ≈365mAhg-1 at 0.1Ag-1, high rate-performance (delivered ≈365/223mAhg-1 at 0.1/10mAg-1) and enhanced cycling performance (≈63.10% capacity retention in the 4000th cycle at 10Ag-1). Furthermore, 1-0.5-4-2 HDEE support feasible Zn-ion storage performance across a wide temperature range (0-80°C) FInally, a ZnǁV10O24·nH2O@rGO pouch-cell prototype fabricated with 1-0.5-4-2 HDEE demonstrates good flexibility, safety, and durability.

Stable Zinc Anode Facilitated by Regenerated Silk Fibroin-modified Hydrogel Protective Layer.

Inherent dendrite growth and side reactions of zinc anode caused by its unstable interface in aqueous electrolytes severely limit the practical applications of zinc-ion batteries (ZIBs). To overcome these challenges, a protective layer for Zn anode inspired by cytomembrane structure is developed with PVA as framework and silk fibroin gel suspension (SFs) as modifier. This PVA/SFs gel-like layer exerts similar to the solid electrolyte interphase, optimizing the anode-electrolyte interface and Zn2+ solvation structure. Through interface improvement, controlled Zn2+ migration/diffusion, and desolvation, this buffer layer effectively inhibits dendrite growth and side reactions. The additional SFs provide functional improvement and better interaction with PVA by abundant functional groups, achieving a robust and durable Zn anode with high reversibility. Thus, the PVA/SFs@Zn symmetric cell exhibits an ultra-long lifespan of 3150 h compared to bare Zn (182 h) at 1.0 mAh cm-2-1.0 mAh cm-2, and excellent reversibility with an average Coulombic efficiency of 99.04% under a large plating capacity for 800 cycles. Moreover, the PVA/SFs@Zn||PANI/CC full cells maintain over 20 000 cycles with over 80% capacity retention under harsh conditions at 5 and 10 A g-1. This SF-modified protective layer for Zn anode suggests a promising strategy for reliable and high-performance ZIBs.

One-Stone-for-Two-Birds Strategy for VSe2 to Enable High Capacity and Long-Life Zinc Storage.

Based on a specific zinc storage mechanism and excellent electronic conductivity, transition metal dichalcogenides, represented by vanadium diselenide, are widely used in aqueous zinc-ion battery (AZIB) energy storage systems. However, most vanadium diselenide cathode materials are presently limited by low specific capacity and poor cycling life. Herein, a simple hydrothermal process has been proposed for obtaining a vanadium diselenide cathode for an AZIB. The interaction of defects and crystal planes enhances zinc storage capacity and reduces the migration energy barrier. Moreover, abundant lamellar structure greatly increases reaction sites and alleviates volume expansion during the electrochemical process. Thus, the as-obtained vanadium diselenide AZIB exhibits an excellent reversible specific capacity of 377 mAh g-1 at 1 A g-1, and ultralong cycle stability of 291 mAh g-1 after 3200 cycles, with a nearly negligible capacity loss. This one-stone-for-two-birds strategy would be expected to be applied to large-scale synthesis of a high-performance zinc-ion battery cathode in the future.

Metal ions and organic molecule co-intercalated vanadium oxide cathode for high-performance zinc-ion batteries

Vanadium oxide is a highly promising cathode material for zinc-ion batteries due to its unique layered structure and high theoretical capacity. However, the material dissolution and structural collapse severely limit the development of zinc-ion batteries. Herein, inorganic metal ions (Mg2+) and organic polymer molecules (PANI) were introduced into the hydrated vanadium oxide interlayer in this paper. Mg2+ ions enhance the conductivity of the cathode and widen the interlayer spacing. Meanwhile, PANI serves to cushion the structural expansion resulting from ion embedding and stabilize the layered structure. Additionally, PANI actively participates in the charging and discharging process, thereby enhancing the diffusion rate of Zn2+. Thanks to the synergistic effect of Mg2+ and PANI, the MgVOH/PANI cathode exhibits a discharge capacity of 412 mAh·g−1 at 0.1 A g−1 and retains 93% of its capacity after 1000 cycles at a current density of 2A·g−1. This synergistic strategy of combining organic molecules and inorganic ions can provide a reference for improving the kinetic and structural stability of other aqueous battery cathodes.

In Situ Constructing Metal-Organic Complex Interface Layer Using Biomolecule Enabling Stabilize Zn Anode.

Aqueous zinc-ion batteries (ZIBs) are considered as a promising candidate for next-generation large-scale energy storage due to their high safety, low cost, and eco-friendliness. Unfortunately, commercialization of ZIBs is severely hindered owing to rampant dendrite growth and detrimental side reactions on the Zn anode. Herein, inspired by the metal-organic complex interphase strategy, the authors apply adenosine triphosphate (ATP) to in situ construct a multifunctional film on the metal Zn surface (marked as ATP@Zn) by a facile etching method. The ATP-induced interfacial layer enhances lipophilicity, promoting uniform Zn2+ flux and further homogenizing Zn deposition. Meanwhile, the functional interlayer improves the anticorrosion ability of the Zn anode, effectively suppressing corrosion and hydrogen evolution. Consequently, the as-prepared ATP@Zn anode in the symmetric cell exhibits eminent plating/stripping reversibility for over 2800h at 5.0mA cm-2 and 1 mAh cm-2. Furthermore, the assembled ATP@Zn||MnO2 full cells are investigated to evaluate practical feasibilities. This work provides an efficient and simple strategy to prepare stabilized Zn anode toward high-performance ZIBs.

Polypyrrole pre-intercalation engineering-induced NH4+ removal in tunnel ammonium vanadate toward high-performance zinc ion batteries

Ammonium vanadate with stable bi-layered structure and superior mass-specific capacity have emerged as competitive cathode materials for aqueous rechargeable zinc-ion batteries (AZIBs). Nevertheless, fragile NH…O bonds and too strong electrostatic interaction by virtue of excessive NH4+ will lead to sluggish Zn2+ ion mobility, further largely affects the electro-chemical performance of ammonium vanadate in AZIBs. The present work incorporates polypyrrole (PPy) to partially replace NH4+ in NH4V4O10 (NVO), resulting in the significantly enlarged interlayers (from 10.1 to 11.9 Å), remarkable electronic conductivity, increased oxygen vacancies and reinforced layered structure. The partial removal of NH4+ will alleviate the irreversible deammoniation to protect the laminate structures from collapse during ion insertion/extraction. The expanded interlayer spacing and the increased oxygen vacancies by the virtue of the introduction of polypyrrole improve the ionic diffusion, enabling exceptional rate performance of NH4V4O10. As expected, the resulting polypyrrole intercalated ammonium vanadate (NVOY) presents a superior discharge capacity of 431.9 mAh g−1 at 0.5 A g−1 and remarkable cycling stability of 219.1 mAh g−1 at 20 A g−1 with 78 % capacity retention after 1500 cycles. The in-situ electrochemical impedance spectroscopy (EIS), in-situ X-ray diffraction (XRD), ex-situ X-ray photoelectron spectroscopy (XPS) and ex-situ high resolution transmission electron microscopy (HR-TEM) analysis investigate a highly reversible intercalation Zn-storage mechanism, and the enhanced the redox kinetics are related to the combined effect of interlayer regulation, high electronic conductivity and oxygen defect engineering by partial substitution NH4+ of PPy incorporation.

Three-dimensional Ordered Macroporous Flexible Electrode Design toward High-Performance Zinc-Ion Batteries.

Flexible zinc-ion batteries (ZIBs) have been considered to have huge potential in portable and wearable electronics due to their high safety, cost efficiency, and considerable energy density. Therein, the design and construction of flexible electrodes significantly determine the performance and lifespan of flexible battery devices. In this work, an ultrathin flexible three-dimensional ordered macroporous (3DOM) Sn@Zn anode (60 μm in thickness) is presented to relieve dendrite growth and expand the lifespan of flexible ZIBs. The 3DOM structure can ensure uniform electric field distribution, guide oriented zinc plating/stripping, and extend the lifespan of anodes. The rich zincophilic Sn sites on the electrode surface significantly facilitate Zn nucleation. Accordingly, a lowered nucleation overpotential of 8.9 mV and an ultralong cycling performance of 2400 h at 0.1 mA cm-2 and 0.1 mAh cm-2 are achieved in symmetric cells, and the 3DOM Sn@Zn anode can also operate in deep cycling for over 200 h at 10 mA cm-2 and 5 mAh cm-2. A flexible 3DOM MnO2/Ni cathode with a high structural stability and a high mass-specific capacity is fabricated to match with the anode to form a flexible ZIB with a total thickness of 200 μm. The flexible device delivers a high volumetric energy density of 11.76 mWh cm-3 at 100 mA gMnO2-1 and a high average open-circuit voltage of 1.5 V and exhibits high-performance power supply under deformation in practical application scenarios. This work may shed some light on the design and fabrication of flexible energy-storage devices.

Steering in-situ low-voltage phase transition from spinel to layered cathode for high-performance zinc-ion batteries

ZnV2O4, as a ternary transition metal oxides (TOMs), has garnered significant attention as a high-performance cathode for zinc-ion batteries (ZIBs) primarily due to its high theoretical capacity and abundance. However, its densely-packed lattice structure and strong coulomb interactions with the guest Zn2+ severely restrict the exposure of active sites and impede the diffusion kinetics. Herein, we propose an innovative in-situ low-voltage phase transition strategy and successfully trigger thorough phase transition of spinel-structured ZnV2O4 to layered-structured Zn3(OH)2V2O7⋅2H2O (ZnVOHNSs). In-depth mechanism analysis reveals that a thorough and efficient transition reaction necessitates meticulous control of the external driving force, reaction kinetics, and the reactant. The activated ZnVOHNSs with large lattice spacing and abundant oxygen vacancies provides an unobstructed pathway for accelerated ion diffusion and abundant exposed active sites for ions storage. Moreover, the inherent structure stability of ZnVOHNSs ensures exceptional reaction stability and reversibility during the Zn2+ intercalation/deintercalation process. Benefiting from these merits, the activated ZnVOHNSs cathode exhibits high reversible capacity and extraordinary rate capability (achieving 369 and 233 mAh g−1 at 0.1 and 20 A g−1, respectively), which exceeds most reported cathode materials in ZIBs. This work unveils the critical phase transition mechanism and offers insight into electrode design for advanced batteries.

Fast and efficient in-situ construction of low crystalline PEDOT-intercalated V2O5 nanosheets for high-performance zinc-ion battery

Layered vanadium oxides have recently emerged as ideal cathode materials for aqueous zinc-ion batteries (ZIBs) due to their high theoretical capacity and low cost. However, their inherent shortages of narrow interlayer distance and poor electric conductivity cause sluggish reaction kinetics and low structure stability, leading to battery performance deterioration. Herein, we developed a novel strategy to simultaneously realize the intercalation of conductive polymer into V2O5 polyhedrons and exfoliation of the V2O5 into ultrathin nanosheets. The strategy is realized by in-situ polymerization of 3,4-ethylene-dioxythiophene (EDOT) monomers in the interlayer of the V2O5 polyhedrons that were derived from the annealing of vanadium-based metal–organic frameworks (MIL-100(V)) in air. The MIL-100-derived V2O5 polyhedrons assembled into porous microspheres (PVO) with abundant porosity and small particle size, which facilitates the penetration of EDOT molecules into the interior of the PVO during in-situ intercalation and polymerization processes, ultimately leading to the V2O5 polyhedrons exfoliating into ultrathin nanosheets. The uniform poly(3,4-ethylene-dioxythiophene) (PEDOT) layer and abundant oxygen vacancies in PVO@PEDOT nanosheets can accelerate the diffusion of electrons and zinc ions, which are evidenced by dynamic analysis, ex-situ characterizations, and density functional theory (DFT) calculations, revealing the synergetic effect of PEDOT and oxygen vacancies. Therefore, the PVO@PEDOT cathode exhibits high specific capacity (403.7 mAh g-1 at 0.2 A g-1), superior rate capability (312.8 mAh g-1 at 10 A g-1), and long-term stability (92.8% of the initial capacity remained after 3000 cycles), which is superior to the majority of ion intercalation improved V2O5.

Recent Advances in Graphene-Based Materials for Zinc-Ion Batteries.

Zinc-ion batteries (ZIBs) are a promising alternative for large-scale energy storage due to their advantages of environmental protection, low cost, and intrinsic safety. However, the utilization of their full potential is still hindered by the sluggish electrode reaction kinetics, poor structural stability, severe Zn dendrite growth, and narrow electrochemical stability window of the whole battery. Graphene-based materials with excellent physicochemical properties hold great promise for addressing the above challenges foe ZIBs. In this review, the energy storage mechanisms and challenges faced by ZIBs are first discussed. Key issues and recent progress in design strategies for graphene-based materials in optimizing the electrochemical performance of ZIBs (anode, cathode, electrolyte, separator and current collector) are then discussed. Finally, some potential challenges and future research directions of graphene-based materials in high-performance ZIBs are proposed for practical applications.

In situ prepared amorphous VOH-Polyaniline@Carbon cloth as cathodes for high performance zinc ion batteries

Vanadium-based compounds are promising cathode materials for aqueous zinc ion batteries (AZIBs) while suffering from notorious poor conductivity and structural instability, leading to severe performance degradation.Herein, we grew polyaniline intercalated VOH nanoarrays on conductive carbon cloth (VOH-PANI@CC) via one-step electrochemical deposition route. Owing to the advantageous nature of amorphous structure of VOH, good conductivity of PANI and the strong synergistic effect between two components, the VOH-PANI@CC free-standing electrodes showed abundant ion diffusion paths, plentiful ion storage sites and high conductivity. The electrode thus achieves an initial charging capacity up to 500 mAh g−1 at 0.1 A g−1 and can still maintain 117.4 mAh g−1 for 500 cycles at 0.5 A g−1. Furthermore, ex-situ XRD and XPS studies revealed the zinc storage process of VOH-PANI@CC and underlying mechanism of the enhanced performance. This work provides a universality design strategy for designing advanced high-performance V-based cathodes for AZIBs.

Constructing ultra-stable and high-performance zinc-ion batteries through Mn doped vanadium oxide nanobelt cathode

In this study, analysis of density functional theory calculations shows that the Mn2+ doping between VO6 layers functions as a “structural pillar,” and Mn2+ in the layer can boost the conductivity of VO2·0.2H2O and hold high specific capacity.

An integrated Janus hydrogel with different hydrophilicities and gradient pore structures for high-performance zinc-ion batteries

In zinc-ion batteries, the role of water in electrolytes is pivotal for enhancing the kinetics and capacity of the cathode; however, an excess of water leads to reduced stability of...

A B-doped layered VOPO4·2H2O cathode for high-performance zinc-ion batteries with an H+/Zn2+ co-insertion mechanism

B-doping engineering provides a strategy to increase the content of V4+ in VOPO4·2H2O and improve its H+/Zn2+ co-intercalation capacitance as a cathode for zinc-ion batteries.

Te hexagonal nanotubes with fast 1-dimensional Zn ion diffusion for high-performance zinc-ion battery cathodes

The need for advanced next-generation secondary batteries have been urgently demanded for improved, sustainable, and eco-friendly energy storage systems. Aqueous rechargeable zinc ion batteries (ARZIBs) have garnered substantial attention as a substitute for lithium-ion batteries owing to their exceptional stability, environmentally friendly features, and cost-effectiveness. In this study, it is found that tellurium hexagonal nanotubes with a unique crystal growth orientation of [001] are of promising cathode materials for enhancing the performance of zinc ion batteries owing to their outstanding reaction kinetic properties. Additionally, the hollow interior of the nanotubes effectively mitigates the volume changes of tellurium during the charging and discharging processes. These research findings are expected to solidify the potential of tellurium hexagonal nanotubes as reliable cathode materials, significantly contributing to the commercialization of zinc ion battery technology in the future.

A Fluorinated Solid-state-electrolyte Interface Layer Guiding Fast Zinc-ion Oriented Deposition in Aqueous Zinc-ion Batteries.

Aqueous zinc ion batteries are gaining popularity due to their high energy density and environmental friendliness. However, random deposition of zinc ions on the anode and sluggish migration of zinc ions on the interface would lead to the growth of zinc dendrites and poor cycling performance. To address these challenges, we developed a fluorinated solid-state-electrolyte interface layer composed of Ca5 (PO4 )3 F/Zn3 (PO4 )2 via an in situ ion exchange strategy to guide zinc-ion oriented deposition and fast zinc ion migration on the anode during cycling. The introduction of Ca5 (PO4 )3 F (FAP) can increase the nucleation sites of zinc ions and guide the oriented deposition of zinc ions along the (002) crystal plane, while the in situ formation of Zn3 (PO4 )2 during cycling can accelerate the migration of zinc ions. Benefited from our design, the assembled Zn//V2 O5  ⋅ H2 O batteries based on FAP-protected Zn anode (FAP-Zn) achieve a higher capacity retention of 84 % (220 mAh g-1 ) than that of bare-Zn based batteries, which have a capacity retention of 23 % (97 mAh g-1 ) at 3.0 A g-1 after 800 cycles. This work provides a new solution for the rational design and development of the solid-state electrolyte interface layer to achieve high-performance zinc-ion batteries.

Hybrid Superlattice-Triggered Selective Proton Grotthuss Intercalation in δ-MnO2 for High-Performance Zinc-Ion Battery.

A great deal of attention has been paid on layered manganese dioxide (δ-MnO2 ) as promising cathode candidate for aqueous zinc-ion battery (ZIB) due to the excellent theoretical capacity, high working voltage and Zn2+ /H+ co-intercalation mechanism. However, caused by the insertion of Zn2+ , the strong coulomb interaction and sluggish diffusion kinetics have resulted in significant structure deformation, insufficient cycle stability and limited rate capability. And it is still far from satisfactory to accurately modulate H+ intercalation for superior electrochemical kinetics. Herein, the terrace-shape δ-MnO2 hybrid superlattice by polyvinylpyrrolidone (PVP) pre-intercalation (PVP-MnO2 ) was proposed with the state-of-the-art ZIBs performance. Local atomic structure characterization and theoretical calculations have been pioneering in confirming the hybrid superlattice-triggered synergy of electron entropy stimulation and selective H+ Grotthuss intercalation. Accordingly, PVP-MnO2 hybrid superlattice exhibits prominent specific capacity (317.2 mAh g-1 at 0.125 A g-1 ), significant rate performance (106.1 mAh g-1 at 12.5 A g-1 ), and remarkable cycle stability at high rate (≈100 % capacity retention after 20,000 cycles at 10 A g-1 ). Therefore, rational design of interlayer configuration paves the pathways to the development of MnO2 superlattice for advanced Zn-MnO2 batteries.

Regulating interfacial ion migration with pillar effect in layer-by-layer inter-embedded MoS2/Ti3C2 for high-performance zinc-ion batteries

Two-dimensional (2D) layered materials have promising prospects for Zn-storage due to their flexible and adjustable interlayer architecture. The strong electrostatic interaction and high diffusion energy barrier, however, lead to slow diffusion kinetics of Zn-ions between the 2D interfaces, limiting its widespread application. Herein, Ti3C2 MXene is introduced into the MoS2 interlayer by the “pillar effect” to assemble a layer-by-layer inter-embedded structure (L-MoS2/Ti3C2), which provides sufficient diffusion channels for Zn-ions. DFT computations and GITT confirm that the L-MoS2/Ti3C2 exhibits superior Zn-ions migration kinetics. Therefore, L-MoS2/Ti3C2 shows excellent long-term cycling stability (75.6% capacity retention after 7000 cycles at 15 A g-1) and glorious high-rate capability (107 mAh g-1 at 20 A g-1). In addition, the practical application of this material is demonstrated by evaluating the performance of L-MoS2/Ti3C2 in flexible quasi-solid-state aqueous zinc ion batteries under various extreme bending conditions, which exhibits good stability under 180° during the 4000 cycles with a capacity retention of 80.5% at 2.0 A g-1.

Decorating carbon quantum dots onto VO2 nanorods to boost electron and ion transport kinetics for high–performance zinc–ion batteries

Rechargeable aqueous Zn–ion batteries (RAZIBs) are regarded as attractive alternatives for large–scale energy storage. V–based cathode materials have gained great attention due to the merits of rich valence states, controllable morphology, diverse crystal structures, and controllable chemical compositions. However, the development of high–performance V–based cathode is still impeded by sluggish electron/ion transport kinetics. To address this issue, this work reveals that the electrochemical performance of the VO2 cathode can be significantly boosted by decorating carbon quantum dots (CQDs) onto the VO2 nanorods via a facile hydrothermal reaction. The VO2/CQDs sample is characterized to have strong interface interaction with the presence of CO bond. Compared to the CQD–free counterpart, the obtained VO2/CQDs sample exhibits higher specific surface area (18.7 vs 4.4 m2 g−1), better electrolyte wettability (53° vs 114° for contact angle), reduced charge–transfer resistance (1.8 vs 19.9 Ω), and facilitated ion diffusion coefficient (1.66 × 10−10 vs 4.56 × 10−11 cm2 s−1). Benefiting from these features, a high attainable capacity of 427 mAh g−1 at 0.2 A g−1 can be reached for VO2/CQDs, corresponding to the specific energy of 333 Wh kg−1 (based on the mass of VO2/CQDs). When the current density increases to 8 A g−1, VO2/CQDs can still deliver 309 mAh g−1, showing great promise for high–rate capability. Moreover, the VO2/CQDs cathode renders stable cycle performance with retaining 229 mAh g−1 after 2000 cycles. By contrast, the unmodified sample demonstrates moderate electrochemical performance (373 and 186 mAh g−1 at 0.2 and 8 A g−1, respectively). The results highlight the importance of the CQDs decoration strategy, which can effectively boost electron/ion transport in oxide–based cathodes for high–performance RAZIBs.

Operando crystal-amorphous transformation cathode for enhanced zinc storage

Aqueous zinc-ion batteries have obtained broad attention due to their high safety, eco-friendliness, and low cost. However, they are still in the developing stage considering the limited candidate of high-performance cathode materials. Furthermore, the intrinsic storage zinc mechanism is also needed to uncover. Here, we propose an operando crystal-amorphous transformation of tunnel-type VOOH and the obtained amorphous V2O5 serves as a high-performance zinc-ion battery cathode. In-situ X-ray diffraction corroborates the unique operando crystal-amorphous transformation of VOOH during the initial charging process. X-ray photoelectron spectroscopy and transmission electron microscopy further demonstrate the element valence evolution and the lattice structure change, respectively. The operando electrochemical crystal-amorphous transformation allows the obtained amorphous V2O5 to achieve the high capacity of ∼ 350.7 mAh g−1, rate performance (151.2 mAh g−1 at 6.4 A g−1), energy and power densities (137 Wh kg−1 at 6831 W kg−1), unveiling a promising approach of cathode materials via operando crystal-amorphous transformation to achieve the enhanced zinc storage.