Aqueous Rechargeable Batteries Research Articles

Superfast Zincophilic Ion Conductor Enables Rapid Interfacial Desolvation Kinetics for Low‐Temperature Zinc Metal Batteries

AbstractLow‐temperature rechargeable aqueous zinc metal batteries (AZMBs) as highly promising candidates for energy storage are largely hindered by huge desolvation energy barriers and depressive Zn2+ migration kinetics. In this work, a superfast zincophilic ion conductor of layered zinc silicate nanosheet (LZS) is constructed on a metallic Zn surface, as an artificial layer and ion diffusion accelerator. The experimental and simulation results reveal the zincophilic ability and layer structure of LZS not only promote the desolvation kinetics of [Zn(H2O)6]2+ but also accelerate the Zn2+ transport kinetics across the anode/electrolyte interface, guiding uniform Zn deposition. Benefiting from these features, the LZS‐modified Zn anodes showcase long‐time stability (over 3300 h) and high Coulombic efficiency with ≈99.8% at 2 mA cm−2, respectively. Even reducing the environment temperature down to 0 °C, ultralong cycling stability up to 3600 h and a distinguished rate performance are realized. Consequently, the assembled Zn@LZS//V2O5‐x full cells deliver superior cyclic stability (344.5 mAh g−1 after 200 cycles at 1 A g−1) and rate capability (285.3 mAh g−1 at 10 A g−1) together with a low self‐discharge rate, highlighting the bright future of low‐temperature AZMBs.

Natural low corrosive phytic acid electrolytes enable green, ultrafast, stable and high-voltage aqueous proton battery

Proton is a promising charge carrier for aqueous rechargeable batteries due to its small ionic radius, fast diffusion kinetics and great abundance in nature. However, commonly-used proton battery electrolytes are strong acids, such as sulfuric acid, phosphoric acid, etc., which always leads to the notorious rapid corrosion of electrode and metal components, and thus the poor cyclability, the limited materials option and high maintenance cost. Here, we reported a new-type high-concentration phytic acid (PA) electrolytes, which exhibits marvellous superiorities including environmental friendliness, low corrosiveness, high ionic conductivity (133.3 mS cm−1) and wide working potential window (∼2.9 V) in contrast to conventional acid electrolytes. The experimental and calculation results indicated that the scarcity of free water in high-concentration PA electrolytes and the desolvation effect of the preferentially absorbed PA interfacial layer on the electrode surface work in synergy to inhibit the water activity and thus prevent electrode dissolution and side reactions. Benefiting from this, the assembled K0.2VO0.6[Fe(CN)6]0.8•6H2O (VHCF)//MoO3 button-type proton battery shows an average discharge voltage of 0.7 V with a pair of well-defined redox peak at about 1.4 V, great rate performance, excellent cycling stability (87.9% capacity retention after 1000 cycles at 5 A g−1) and superb coulombic efficiency at various current densities (1 A g−1–50 A g−1). Attributed to good anti-freezing properties of the electrolytes, the proton battery can also run normally at -60 °C and exhibit competent performance (a capacity retention of 45 mAh g−1 at 0.1 A g−1 after 540 cycles). Such green low corrosive electrolyte will be fully compatible with conventional battery fabrication process, and open brand new avenue for the development of aqueous proton battery.

Revealing Hydrogen Bond Effect in Rechargeable Aqueous Zinc-Organic Batteries.

The surrounding hydrogen bond (H-bond) interaction around the active sites plays indispensable functions in enabling the organic electrode materials (OEMs) to fulfill their roles as ion reservoirs in aqueous zinc-organic batteries (ZOBs). Despite important, there are still no works could fully shed its real effects light on. Herein, quinone-based small molecules with a H-bond evolution model has been rationally selected to disclose the regulation and equilibration of H-bond interaction between OEMs, and OEM and the electrolyte. It has been found that only a suitable H-bond interaction could make the OEMs fully liberate their potential performance. Accordingly, the 2,5-diaminocyclohexa-2,5-diene-1,4-dione (DABQ) with elaborately designed H-bond structure exhibits a capacity of 193.3 mA h g-1 at a record-high mass loading of 66.2 mg cm-2 and 100% capacity retention after 1500 cycles at 5 A g-1. In addition, the DABQ//Zn battery also possesses air-rechargeable ability by utilizing the chemistry redox of proton. Our results put forward a specific pathway to precise utilization of H-bond to liberate the performance of OEMs.

Heavily vanadium-doped LiFePO4 olivine as electrode material for Li-ion aqueous rechargeable batteries

Since LiFePO4 batteries play a major role in the transition to safe, more affordable and sustainable energy production, numerous strategies have been applied to modify LFP cathode, with the aim of improving its electrochemistry. In this contribution, a highly vanadium-doped LiFe0.9V0.1PO4/C composite (LFP/C-10V) is synthesized using the glycine combustion method and characterized by x-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetry Differential Thermal Analysis (TGDTA) and Cyclic Voltammetry (CV). It is shown that 10wt.% of vanadium can substitute Fe positions, thus decreasing unit cell volume, which is followed by generation of Li3V2PO4 traces, as detected by CV. High vanadium doping does not change the carbon content in the composite (≈13 wt%) but improves its electronic conductivity and electrochemical performance in both aqueous and organic electrolytes. The reversibility and current response are increasing following the trend: LFP/C, LFP/C -3mol%V, LFP/C - 5 mol % and LFP/C-10 mol %. The best specific capacity is obtained for the most highly doped olivine, which exhibits a reversible process at 1 mV s−1 in an aqueous electrolyte, thus showing a peak-to-peak distance of 56 mV. The high capacity of LFPC-10V is measured in both LiNO3 and NaNO3 electrolytes amounting to around 100 mAh g−1 at 20 mV s−1. Still, the material is only stable in LiNO3 electrolyte, making it more suitable for Li than Na-ion aqueous rechargeable batteries.

Strategies of regulating Zn2+ solvation structures toward advanced aqueous zinc-based batteries

Rechargeable aqueous zinc-based batteries not only pave the way for environmentally friendly and safe energy storage devices but also hold great promise for reducing the manufacturing costs of next-generation batteries, positioning them as the most promising energy storage system to replace lithium-ion batteries. However, the commercial application of aqueous zinc-based batteries (AZBs) is severely constrained by issues such as zinc dendrites, hydrogen evolution reaction (HER), and electrode corrosion. While significant efforts have been devoted to exploring electrode materials and their storage mechanisms in this system in recent years, research on the nature of Zn2+ solvation in electrolytes remains insufficient. Therefore, this review primarily provides a comprehensive and in-depth elucidation of the existing issues such as dendrite formation, hydrogen/oxygen evolution, electrode corrosion and passivation interactions. Additionally, from the perspective of electrolyte optimization, this review emphasizes existing strategies to address Zn2+ solvation, including adjusting electrolyte concentration, incorporating functional additives or co-solvents, utilizing ionic liquids, and developing hydrogel electrolytes, and summarizes approaches and mechanisms for improving their relevant performance. Finally, prospects for electrolyte modification and innovation directions of AZBs are proposed, providing guidance for future AZB studies.

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.

Achieving Highly Stable Zn Metal Anodes at Low Temperature via Regulating Electrolyte Solvation Structure.

Zinc metal is an attractive anode material for rechargeable aqueous Zn-ion batteries (ZIBs). However, the dendrite growth, water-induced parasitic reactions, and freezing problem of aqueous electrolyte at low temperatures are the major roadblocks that hinder the widely commercialization of ZIBs. Herein, tetrahydrofuran (THF) is proposed as the electrolyte additive to improve the reversibility and stability of Zn anode. Theoretical calculation and experimental results reveal that the introduction of THF into the aqueous electrolyte can optimize the solvation structure which can effectively alleviate the H2O-induced side reactions and protect the Zn anode from corrosion. Moreover, THF can act as a hydrogen bond acceptor to interact with H2O, which can greatly reduce the activity of free H2O in electrolytes and improve the low-temperature electrochemical performance of Zn anode. As a result, the Zn anodes demonstrate high cyclic stability for 2800h at 27°C and over 4000h at -10°C at 1.0mA cm-2 /1.0mAhcm-2. The full cell exhibits excellent cyclic stability and rate capability at 27 and -10°C. This work is expected to provide a new approach to regulate the aqueous electrolyte and Zn anode interface chemistry for highly stable and reversible Zn anodes.

High mass loading potassium ion stabilized manganese dioxide nanowire forests for rechargeable Zn batteries

Manganese dioxide (MnO2) represents an ideal cathode material for rechargeable aqueous Zn batteries due to its high theoretical capacity (308 mAh g−1), suitable potential (1.4 V vs. Zn2+/Zn), natural abundance, and negligible toxicity. However, the capacity and rate capability of MnO2 deteriorate significantly in thick electrodes owing to its low electrical and ionic conductivities. Herein, we report the design of high mass loading potassium ion stabilized α-MnO2 (K0.133MnO2) nanowire forests on carbon cloth through a seed-assisted hydrothermal method for Zn batteries. The vertically aligned K0.133MnO2 nanowire forests with uninterrupted charge transport afford a high area capacity of 3.54 mAh cm−2 and a capacity retention of 79.2% over 1000 cycles in aqueous electrolyte. Moreover, the high area capacity and cyclability can be readily transferred to quasi-solid-state devices.

Phytic Acid Customized Hydrogel Polymer Electrolyte and Prussian Blue Analogue Cathode Material for Rechargeable Zinc Metal Hydrogel Batteries.

Zinc anode deterioration in aqueous electrolytes, and Zn dendrite growth is a major concern in the operation of aqueous rechargeable Zn metal batteries (AZMBs). To tackle this,the replacement of aqueous electrolytes with a zinc hydrogel polymer electrolyte (ZHPE) is presented in this study. This method involves structural modifications of the ZHPE by phytic acid through an ultraviolet (UV) light-induced photopolymerization process. The high membrane flexibility, high ionic conductivity (0.085Scm-1), improved zinc corrosion overpotential, and enhanced electrochemical stability value of ≈2.3V versus Zn|Zn2+ show the great potential of ZHPE as an ideal gel electrolyte for rechargeable zinc metal hydrogel batteries (ZMHBs). This is the first time that the dominating effect of chelation of phytic acid with M2+ center over H-bonding with water is described to tune the gel electrolyte properties for battery applications. The ZHPE shows ultra-high stability over 360h with a capacity of 0.50mAhcm-2 with dendrite-free plating/stripping in Zn||Zn symmetric cell. The fabrication of the ZMHB with a high-voltage zinc hexacyanoferrate (ZHF) cathode shows a high-average voltage of ≈1.6V and a comparable capacity output of 63mAhg-1 at 0.10Ag-1 of the current rate validating the potential application of ZHPE.

Hybrid-Electrolytes System Established by Dual Super-lyophobic Membrane Enabling High-Voltage Aqueous Lithium Metal Batteries.

Aqueous electrolytes and related aqueous rechargeable batteries own unique advantage on safety and environmental friendliness, but coupling high energy density Li-metal batteries with aqueous electrolyte still represent challenging and not yet reported. Here, this work makes a breakthrough in "high-voltage aqueous Li-metal batteries" (HVALMBs) by adopting a brilliant hybrid-electrolytes strategy. Concentrated ternary-salts ether-based electrolyte (CTE) acts as the anolyte to ensure the stability and reversibility of Li-metal plating/stripping. Eco-friendly water-in-salt (WiS) electrolyte acts as catholyte to support the healthy operation of high-voltage cathodes. Most importantly, the aqueous catholyte and non-aqueous anolyte are isolated in each independent chamber without any crosstalk. Aqueous catholyte permeation toward Li anode can be completely prohibited without proton-induced corrosion, which is enabled by the introduction of under-liquid dual super-lyophobic membrane-based separator, which can realize the segregation of the most effective immiscible electrolytes with a surface tension difference as small as 6 mJ m-2. As a result, the aqueous electrolyte can be successfully coupled with Li-metal anode and achieve the fabrication of HVALMBs (hybrid-electrolytes system), which presents long-term cycle stability with a capacity retention of 81.0% after 300 cycles (LiNi0.8Mn0.1Co0.1O2 || Li (limited) cell) and high energy density (682Whkg-1).

Potassium-Hydrogen Hybrid Ion Alkaline Battery: A New Rechargeable Aqueous Battery Combined a K+ Storage Cathode and an Electrochemical Hydrogen Storage Anode.

A rechargeable aqueous hybrid ion alkaline battery, using a proton and a potassium ion as charge carriers for the anode and cathode, respectively, is proposed in this study by using well-developed potassium nickel hexacyanoferrate as the cathode material and mesoporous carbon sheets as the anode material, respectively. The constructed battery operates in a concentrated KOH solution, in which the energy storage mechanism for potassium nickel hexacyanoferrate involves the redox reaction of Fe2+/Fe3+ associated with potassium ion insertion/extraction and the redox reaction of Ni(OH)2/NiOOH. The mechanism for the carbon anode is electrochemical hydrogen storage. The cathode made of potassium nickel hexacyanoferrate exhibits both an ultrahigh capacity of 232.7 mAh g-1 under 100 mA g-1 and a consistent performance of 214 mAh g-1 at 2000 mA g-1 (with a capacity retention of 92.8% after 200 cycles). The mesoporous carbon sheet anode exhibits a capacity of 87.6 mAh·g-1 at 100 mA g-1 with a good rate and cyclic performance. The full cell provides an operational voltage of 1.55 V, a capacity of 93.6 mAh g-1 at 100 mA g-1, and 82.4% capacity retention after 1000 cycles at 2000 mA g-1 along with a low self-discharge rate. The investigation and discussion about the energy storage mechanisms for both electrode materials are also provided.

A Natural Casein-Based Separator with Brick-and-Mortar Structure for Stable, High-Rate Proton Batteries.

Rechargeable aqueous proton batteries with small organic molecule anodes are currently considered promising candidates for large-scale energy storage due to their low cost, stable safety, and environmental friendliness. However, the practical application is limited by the poor cycling stability caused by the shuttling of soluble organic molecules between electrodes. Herein, a cell separator is modified by a GO-casein-Cu2+ layer with a brick-and-mortar structure to inhibit the shuttling of small organic molecules. Experimental and calculation results indicate that, attributed to the synergistic effect of physical blocking of casein molecular chains and electrostatic and coordination interactions of Cu2+, bulk dissolution and shuttling of multiple small molecules can be inhibited simultaneously, while H+ transfer across the separators is not almost affected. With the protection of the GO-casein-Cu2+ separator, soluble small molecules, such as diquinoxalino[2,3-a:2',3'-c]phenazine,2,3,8,9,14,15-hexacyano (6CN-DQPZ) exhibit a high reversible capacity of 262.6 mA h g-1 and amazing stability (capacity retention of 92.9% after 1000 cycles at 1 A g-1). In addition, this strategy is also proved available to other active conjugated small molecules, such as indanthrone (IDT), providing a general green sustainable strategy for advancing the use of small organic molecule electrodes in proton cells.

Synthesis of Aminopolyolefins with Tunable Hydrophilicity and Chain Flexibility for Application as Binders in Aqueous Rechargeable Batteries

Synthesis of Aminopolyolefins with Tunable Hydrophilicity and Chain Flexibility for Application as Binders in Aqueous Rechargeable Batteries

Zinc Powder Anodes for Rechargeable Aqueous Zinc-Based Batteries.

Aqueous rechargeable zinc-based batteries hold great promise for energy storage applications, with most research utilizing zinc foils as the anode. Conversely, the high tunability of zinc powder (Zn-P) makes it an ideal choice for zinc-based batteries, seamlessly integrating with current battery production technologies. However, challenges such as contact loss, dendrite formation, and a high tendency for corrosion significantly hamper the performance enhancement of Zn-P anodes. This review provides an overview of strategies adopted from various perspectives, including zinc powder optimization, electrode engineering, and electrolyte modification, to address these issues. Additionally, it explores the limitations of existing research and offers valuable insights into potential future directions for further advancements in Zn-P anodes.

Regulating ionic transport and interface chemistry via high-dielectric BaTiO3 porous scaffolds for aqueous Zn-ion batteries

Rechargeable aqueous Zn-ion batteries (AZIBs) are gaining considerable attention as alternatives to Li-ion batteries owing to their excellent safety, high energy density, low cost, and environmental friendliness. However, their Zn anodes suffer from severe dendritic growth, the hydrogen evolution reaction (HER), and corrosion, which limit the commercialization of AZIBs. To address this challenge, we designed a solution involving the development of a high-dielectric hydrophobic BaTiO3 (BTO) porous scaffold layer that is strategically applied to the Zn surface. This BTO layer effectively impedes the dendritic growth of Zn. The distinct polarizability of the BTO layer actively diminishes the electric-field gradient, thereby minimizing the interaction between the H2O molecules and the Zn surface. This phenomenon helps suppress dendritic growth, thus ensuring the uniform deposition of Zn and preventing the HER. The electrochemical performance of a symmetric cell containing the Zn@BTO electrode exhibits low-voltage polarization and stable charge–discharge performance for up to 500 h. In addition, a full-cell AZIB containing a high-capacity α-MnO2 cathode and Zn@BTO anode exhibits good rate capability and a long life of up to 500 cycles. This study demonstrates the development of a cost-effective dendrite-free Zn anode integrated with a highly dielectric hydrophobic BTO porous scaffold layer as a stable Zn–electrolyte interface layer for high-performance AZIBs.

Bifunctional oxygen electrocatalyst based on Fe, Co, and nitrogen co-doped graphene-coated alumina nanofibers for Zn-air battery air electrode

Aqueous rechargeable zinc-air battery (RZAB) is an emerging environmentally friendly energy storage device for a wide variety of industrial applications such as electric vehicles, consumer electronics, and stationary power plants. For successful commercialization of RZABs, a cost-effective bifunctional catalyst is highly required to catalyze the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the air electrode. Dual transition-metal and nitrogen-doped nanocarbon materials have shown good potential as an affordable and scalable bifunctional oxygen electrocatalysts alternative to Pt-group metal-based catalysts for RZAB. To achieve this goal, we have developed electrocatalysts based on Fe, Co, and nitrogen co-doped graphene-augmented inorganic alumina nanofibers (Fe/Co-NGr). The Fe/Co-NGr catalysts demonstrate high oxygen reduction and evolution reaction reversibility (ΔE) of 0.85–0.88 V due to the graphene-covered nanofibrous structure doped with FeCo alloy nanoparticles and containing nitrogen, transition metal (TM) coordinated to nitrogen and TM oxide active sites. The primary zinc-air battery with Fe/Co-NGr air electrode exhibits a high maximum power density of 149 mW cm−2 and a specific capacity of 807 mAh gZn-1. The RZAB assessment has shown a low charge–discharge voltage gap of 0.86 V and high energy utilization efficiency of 58 % up to 90 h of charge–discharge cycling at 5 mA cm−2.

Synthesis and electrochemical studies of 1,1’-binaphthyl-2,2’-diol for aqueous rechargeable lithium-ion battery applications

The constant increase in the utilization of lithium-ion batteries (LIBs) in various field applications, including electrical vehicles and electronic devices, has led researchers to focus on their multiple path developments to obtain new electrode materials. The practical development of these electrode materials, based on organic and inorganic moieties, is challenging for various groups of LIB scientists. The concept of organic electrode materials is highly competitive with inorganic electrode materials because of the accessibility of more active sites with structural diversity, high energy and power density, environmental friendliness potential sustainability, and low cost. Herein, 1,1’-binaphthyl-2,2’-diol (BINOL) is investigated as an organic electrode material that contains two hydroxyl groups that act as active centers. The oxidative coupling process is employed to synthesize BINOL and so obtained product was characterized by using FT-IR, 1H-NMR and MASS techniques. The electrochemical investigations were carried out using sat. Li2SO4 electrolytic medium at three-electrode cell system. The Cyclic voltammetry (CV) has provided information on the anodic behavior of the material and its stability studied at different scan rates. The battery performance of the cell BINOL | Sat. Li2SO4 | LiMn2O4 by galvanostatic charge-discharge potential limit (GCPL) shows 197/171mAhg−1 specific capacity and 90% columbic efficiency. The electrochemical kinetic obtained by potentiostatic electrochemical impedance spectroscopy (PEIS) shows a semi-infinite diffusion process.

High-rate aqueous magnesium ion battery enabled by Li/Mg hybrid superconcentrated electrolyte

Rechargeable aqueous magnesium ion batteries (AMIBs) are considered a promising energy storage system due to the relatively high energy density, excellent rate performance and reversibility, and absence of dendrite formation during cycling. However, the high surface charge density of Mg2+ ions results in slow diffusion kinetics, and high voltage leads to excessive electrolyte decomposition at the electrode/aqueous electrolyte interface, thereby limiting the development of high-energy–density MIBs. In this work, we extend the electrochemical stability window of the aqueous electrolyte to 2.1 V by using a hybrid ion superconcentrated electrolyte at concentrations not achievable with Mg2+ electrolytes alone. The AMIB with a water-in-salt (WIS) electrolyte delivers discharge capacities of up to 200.6 and 84.4 mAh g−1, and energy densities of 170.1 and 68.1 Wh Kg−1 at 0.5 and 20 A g−1, respectively, representing excellent rate performance, while retaining 85 % of the specific capacity after 2000 cycles. Additionally, we explore the corresponding electrochemical reaction mechanism, revealing the synergistic effect of Mg2+ and Li+ ions in the charge/discharge process, which supports the excellent electrochemical performance of AMIB.

Dynamic Molecular Interphases Regulated by Trace Dual Electrolyte Additives for Ultralong-Lifespan and Dendrite-Free Zinc Metal Anode.

Metallic zinc is a promising anode material for rechargeable aqueous multivalent metal-ion batteries due to its high capacity and low cost. However, the practical use is always beset by severe dendrite growth and parasitic side reactions occurring at anode/electrolyte interface. Here we demonstrate dynamic molecular interphases caused by trace dual electrolyte additives of D-mannose and sodium lignosulfonate for ultralong-lifespan and dendrite-free zinc anode. Triggered by plating and stripping electric fields, the D-mannose and lignosulfonate species are alternately and reversibly (de-)adsorbed on Zn metal, respectively, to accelerate Zn2+ transportation for uniform Zn nucleation and deposition and inhibit side reactions for high Coulombic efficiency. As a result, Zn anode in such dual-additive electrolyte exhibits highly reversible and dendrite-free Zn stripping/plating behaviors for >6400 hours at 1 mA cm-2, which enables long-term cycling stability of Zn||ZnxMnO2 full cell for more than 2000 cycles.

Nutrient for Inhibiting the Activity of H2O and Optimizing Interfacial Chemistry for Aqueous Rechargeable Zn-Ion Batteries

Nutrient for Inhibiting the Activity of H₂O and Optimizing Interfacial Chemistry for Aqueous Rechargeable Zn-Ion Batteries