Rechargeable Zn-ion Batteries Research Articles

High capacity and inexpensive multivalent cathode materials for aqueous rechargeable Zn-ion battery fabricated via in situ electrochemical oxidation of VO2 nanorods

For large-scale energy storage, aqueous rechargeable zinc-ion batteries are one of the most promising battery systems to replace lithium-ion batteries. In this study, a facile and scalable hydrothermal method is used to prepare VO2 nanorods, which are ball-milled with carbon black to prepare VO2@C nanoparticles. Characterizations using several advanced techniques confirm the successful synthesis of pure VO2 nanorods. Prior to electrochemical measurements, the VO2@C nanostructured cathode materials are transformed into V2O5·nH2O via an in situ electrochemical oxidation technique. The VO2@C/Zn aqueous zinc-ion full cell exhibits a reversible capacity of 300 mA h g−1 and a retention capacity of 85% after 1000 cycles at a current density of 5 A g−1 with a 2 M ZnSO4 electrolyte. The full cell also retains a remarkable capacity of 159 mA h g−1, even after 4000 galvanostatic charge–discharge cycles at 5 A g−1. The cell also shows excellent rate capabilities at a wide range of current densities from 0.1 to 20 A g−1, with a reversible discharge capacity and Coulombic efficiency of 100 mA h g−1 and 99%, respectively, at 20 A g−1. The remarkable performance is attributed to the nanoscale size of the prepared nanorods and the in situ electrochemical transformation.

Zn anode sustaining high rate and high loading in organic electrolyte for rechargeable batteries

Rechargeable aqueous Zn battery, the promising candidate for future energy storage devices still suffers from multiple disadvantages of low reversibility, uncontrolled dendrite growth, and limited electrochemical potential window. Alternatively, organic electrolytes can theoretically resolve the thermodynamic instability of Zn anode, but at the expense of high-rate capability due to their inferior ionic conductivity. Here we report N, N-dimethyl formamide (DMF) based non-aqueous electrolyte containing Cu2+ ions as an additive (Cu2+-DMF). The combined effect of high thermodynamic stability of Zn anode in DMF electrolyte and in-vitro Cu-Zn alloy interphase can surpass both aqueous and non-aqueous electrolyte performance. High-rate capability, low overpotential of ∼50 mV at 20.0 mA cm−2/20.0 mAh cm−2, supreme stability over 1400 h at 5.0 mA cm−2/5.0 mAh cm−2, high Coulombic efficiency (CE, ∼99.60 %) and wide electrochemical stability window (∼2.45 V vs. Zn/Zn2+) is observed for Cu2+-DMF electrolyte. As a proof-of-concept, Zn||δ-MnO2 battery configuration in DMF electrolyte exhibits stable cycling, high-rate capability, and excellent reversibility. For deep understanding, the electrochemical kinetics and storage mechanism are also validated through multiple characterization techniques. This work is a substantial step towards the cost-effective construction of rechargeable non-aqueous Zn ion batteries.

A dendrite-free anode for stable aqueous rechargeable zinc-ion batteries

Due to its low cost, high specific co, and environmental friendliness, zinc is considered a potential anode material for aqueous rechargeable Zn-ion batteries. However, practical applications remain a challenge due to uncontrolled dendrite formation. Herein, we have utilized a strategy where a microporous nanofiber layer of polyacrylonitrile (PAN) is electrospun onto Cu foil and used as the current collector for the anode to inhibit dendrite generation. The polar nitrile groups on the nanofibers expedite the uniform transport of Zn2+ and allow homogenous Zn deposition, which ultimately inhibits dendrite growth. The symmetrical cell equipped with this new fabricated electrode shows over 270 stable cycles without a short circuit. The full cell formed with MnO2 as the cathode exhibits improved cycle stability up to 300 cycles at a current density of 0.5 A g−1.

The charge density of intercalants inside layered birnessite manganese oxide nanosheets determining Zn-ion storage capability towards rechargeable Zn-ion batteries

Rechargeable aqueous Zn–MnO2 batteries have been considered as one of the promising alternative energy technologies due to their high abundance, environmental friendliness, and safety of both Zn–metal anodes and manganese oxide cathodes.

Synthesis, characterisation, and feasibility studies on the use of vanadium tellurate(vi) as a cathode material for aqueous rechargeable Zn-ion batteries.

Aqueous rechargeable zinc-ion batteries (AZIBs) have drawn enormous attention in stationary applications due to their high safety and low cost. However, the search for new positive electrode materials with satisfactory electrochemical performance for practical applications remains a challenge. In this work, we report a comprehensive study on the use of the vanadium tellurate (NH4)4{(VO2)2[Te2O8(OH)2]}·2H2O, which is tested for the first time as a cathode material in AZIBs.

RGO/Manganese Silicate/MOF-derived carbon Double-Sandwich-Like structure as the cathode material for aqueous rechargeable Zn-ion batteries

Aqueous rechargeable Zn-ion batteries (ARZIBs) have been attracting a great deal of attention due to their immense potential in large-scale power grid applications. It is of great significance to explore cathode material with novel designed structure and first-class performances for ARZIBs. Herein, we successfully construct a double-sandwich-like structure, MOF-derived carbon/manganese silicate/reduced graphene oxide/manganese silicate/MOF-derived carbon (denoted as rGO/MnSi/MOF-C), as the cathode material for ARZIBs. Among the double-sandwich-like structure, manganese silicate (Mn2SiO4, denoted as MnSi) is in the middle of internal reduced graphene oxide (rGO) and external MOF-8 derived carbon (MOF-C). This integrated rGO/MnSi/MOF-C with double-sandwich-like structure can not only avert the sluggish electronic conduction progress caused by the conventional three-phase mixture system of rGO, MnSi and MOF-C, but also display promising Zn2+ storing capability. As expected, in mild aqueous 2 M (mol L−1) ZnSO4 + 0.2 M MnSO4 electrolyte, the initial discharge capacity of rGO/MnSi/MOF-C cathode reaches to 246 mAh·g−1, and the peak discharge capacity reaches to 462 mAh·g−1 at 0.1 A·g−1. This work not only involves the novel MnSi-based cathode for ARZIBs, but also first demonstrates our assumption of constructing the double-sandwich-like structure to improve Zn2+ storage. Moreover, the concept “double-sandwich-like structure” provides an idea for synthesizing the integrated carbon/transition metal silicates (TMSs)/carbon structure to boost the electrochemical properties of TMSs for energy-storing devices.

Electrochemical Activation to Unlock the Potential of Manganese Sulfide As High-Performance Cathodes for Rechargeable Aqueous Zn-Ion Batteries

The broad implementation of review energy to the electrical grid requires the development of highly safe and low-cost batteries. The rechargeable aqueous Zn/MnO2 batteries have been considered a promising candidate for large-scale energy storage devices. However, MnO2 cathode suffers from poor capacity and cyclability due to the inferior utilization of electrochemically active surface area and manganese dissolution during cycling. Herein, we report a compelling manganese oxide cathode for aqueous rechargeable Zn ion batteries, which was derived from MnS precursor through in situ electrochemical activation process. Such electrochemical activation approach induces abundant defects and active sites to unlock the electrochemical reactivity of MnS derived oxide cathode (MnS-EDO). Benefiting from the large electrochemically active areas and fast ion diffusion kinetics, MnS-EDO exhibits high capacity utilization and outstanding long-term cyclability. At 300 mA g-1, a high specific capacity of 335 mAh g-1 can be achieved after 100 cycles. At 3000 mA g-1, an exceptional cycling performance can be maintained over 4000 cycles without obvious capacity loss. Moreover, the underlying electrochemical mechanisms are systematically investigated. This work opens a new approach for the future development of high-performance manganese oxide-based cathodes.

Mn3O4@MnS composite nanoparticles as cathode materials for aqueous rechargeable Zn ion batteries

Exploring high-capacity and stable cathode materials for aqueous rechargeable Zn ion batteries (ZIBs) is highly attractive but challenging. Herein, we present a kind of Mn3O4@MnS heterostructured nanoparticle as a robust ZIB cathode. These Mn3O4@MnS nanoparticles are facilely synthesized by in-situ transformation of MnO2 under sulfidation thermal treatment. Owing to the heterostructured architecture and improved electrical conductivity, the as-obtained Mn3O4@MnS nanoparticles afford a stable capacity of 128.3 mA h g[Formula: see text] at 2 mA cm[Formula: see text] and good stability of more than 65% capacity retention after 1000 cycles. Additionally, a remarkably energy density of 184.72 Wh kg[Formula: see text] is also achieved by the assembled Zn//Mn3O4@MnS battery. This work paves the way for constructing Mn-based heterostructures as high-performance cathodes in aqueous ZIBs.

Flexible solid-state Zn-polymer batteries with practical functions

The skyrocketing progress of wearable electronics has urged the development of advanced batteries that can adapt to various conditions in practical applications, such as mechanical impact, bending, cutting, or freezing. Herein, solid-state rechargeable Zn-ion batteries (ZIBs) based on the poly(4,4′-oxydiphenol)-modified nanoporous carbon cathode is presented. By using an anti-freeze gelled electrolyte, the sandwich-structured flat cell exhibits stable electrochemical performance under mechanical impact and good working condition after being partially cropped. Also, the device being cut into halves can be re-connected to resume its powering function, showing a self-healable behaviour. Our temperature-dependent tests from 25 to –20 °C reveal that the operating voltage window of the solid-state ZIB can be widened at low temperatures, thus increasing the capacity despite of the reduced redox activity of the polymer electrode. Even the device capacity at –25 °C is a bit higher than that at room temperature. In addition, the ZIB delivers a flat discharge plateau around 1.15 V, higher than those of most other Zn-organic cells ever reported. To understand the charge storage mechanism, the H+ and Zn2+ co-insertion mechanism is investigated by combing theory with experiment.

Polyaniline-expanded the interlayer spacing of hydrated vanadium pentoxide by the interface-intercalation for aqueous rechargeable Zn-ion batteries

The metal ions or conductive macromolecules intercalated hydrated vanadium oxides for aqueous Zn-ion batteries (AZIBs) have received increasing attention in recent years. The strategy for the preparation of the intercalated hydrated vanadium oxides has been achieved great advances but is still a huge challenge. In this contribution, we develop an interface-intercalation method to synthesize the polyaniline-intercalated hydrated vanadium pentoxide (V2O5·nH2O), denoted as PANI-VOH, as the cathode materials for AZIBs. The prepared PANI-VOH exhibits a 3D sponge-like morphology and the surface area of 190 m2·g−1. The interlayer spacing of VOH is expanded to be 14.1 Å, which provides a lot of channels for the rapidly reversible (de)intercalation of Zn2+ ions. The coin-typed Zn//PANI-VOH battery shows the specific discharge capacity of 363 mAh·g−1 at 0.1 A·g−1 and stable cycling performance. Furthermore, the specific capacity remains 131 mAh·g−1 after 2000 cycles at 5 A·g−1, and the energy density is calculated to be 275 Wh·kg−1 at 78 W·kg−1 on the mass of PANI-VOH. The achieved values are comparable to or even much higher than that of the most state-of-the-art V-based cathode materials for AZIBs. The PANI intercalation can shorten the pathways and facilitate the transports for the migration of ions and electrons. Our finding guides a novel strategy for the intercalation of PANI into the layered materials to adjust their interlayer spacing, which exhibits super ions migration efficiency, as the cathode materials for AZIBs and even other multivalent ions batteries.

Synthesis, Characterization and Electrochemical Evaluation of Layered Vanadium Phosphates as Cathode Material for Aqueous Rechargeable Zn-ion Batteries

The potential application of rechargeable multivalent ion batteries in portable devices and renewable energy grid integration have gained substantial research interest in aqueous Zn-ion batteries (ZIBs). Compared to Li-based batteries, ZIBs offer lower costs, higher energy density, and safety that make them more attractive for energy storage in grid integration applications. Currently, more research is required to find a suitable cathode material for ZIBs with high capacity and structural stability during charge/discharge cycling. Vanadium phosphate (VOP) compounds as cathode material for ZIBs have been of particular interest, owing to vanadium’s diverse oxidation states. In this present work, two VOP compounds, [H0.6(VO)3(PO4)3(H2O)3].4H2O and VOPO4.2H2O, were synthesized from phosphoric acid and different sources of vanadium via a simple hydrothermal method. Various characterization techniques were carried out, revealing the layered structure of both products and high purity of [H0.6(VO)3(PO4)3(H2O)3].4H2O. Zn/VOP batteries were prepared using Zn metal as counter and reference electrode and 3 M ZnSO4.7H2O as electrolyte. Electrochemical tests were conducted to evaluate the cycling performance of VOPs as cathode material for aqueous Zn-ion batteries. Based on the results, both compounds have shown highly reversible Zn-ion intercalation and deintercalation. VOPO4.2H2O achieved a higher specific capacity of up to 85 mAh/g during discharging, as opposed to 65 mAh/g for the hydrated VOP complex. However, [H0.6(VO)3(PO4)3(H2O)3].4H2O is more stable with higher reproducibility than VOPO4.2H2O during cycling. Nevertheless, more research is still required to enhance the specific capacity and improve the cycling performance of VOP-based cathodes for their prospective use in aqueous ZIBs.

Defect modulation of ZnMn2O4 nanotube arrays as high-rate and durable cathode for flexible quasi-solid-state zinc ion battery

• A novel N-ZMO NTAs is developed as advanced cathode for ZIBs. • The N-ZMO NTAs have high electrical conductivity and stable architecture. • The flexible quasi-solid-state ZIBs show decent energy/power density with long-term stability. The exploration of a stable and high-rate cathode is very important for rechargeable Zn ion batteries (ZIBs). With unique merits of rich abundance, low price, and environmental friendliness, spinel ZnMn 2 O 4 (ZMO) hold great promise as a cathode material for ZIBs. However, its inherent low electronic conductivity and large volume variation in the process of charge/discharge severely restrict the rate capability and durability. Herein, the novel N-doping coupled oxygen vacancies modulated ZMO nanotube arrays (NTAs) (N-ZMO NTAs) are fabricated as high-performance cathode for rechargeable ZIBs. Taking advantages of high electrical conductivity, fast ion diffusion, high surface area, sufficient active sites, and stable hollow nanotubular architecture, the N-ZMO NTAs show an admirable capacity (223 mA h g −1 at 0.1 A g −1 ), decent rate capability (133.3 mA h g −1 at 4 A g −1 ) and distinguished long-term durability (92.1% after 1500 cycles). Furthermore, a flexible quasi-solid-state ZIBs is fabricated with N-ZMO NTAs cathode, which achieves favorable energy density (214.6 W h kg −1 ), superb power density (4 kW kg −1 ), and impressive long-term stability (88.6% after 1500 cycles), outperforming most state-of-the-art ZIBs. This study may shed light on designing advanced cathodes for advanced ZIBs.

Enhanced and stabilized charge transport boosting by Fe-doping effect of V2O5 nanorod for rechargeable Zn-ion battery

As a result of prices of fossil fuels and the increased energy demand, reasonable utilization of renewable energy sources has become a global topic, rechargeable aqueous zinc-ion batteries (ZIBs) are considered as the large-scale energy storage because there is an abundant zinc source, and ZIBs provide reliable safety, eco-friendliness, and high specific capacity. Nevertheless, the limited electroactive sites and low electrical conductivity of vanadium oxide (V2O5)-based cathode for ZIBs inevitably destabilizes the energy storing reactions, impeding the diffusion of zinc ion and electron movement. Here, to lower the insertion energetics and diffusion barriers of zinc ion, we reported iron (Fe)-doped V2O5 with the nanorod architecture by utilization of electrospun polyacrylonitrile fiber templates; these exhibited a high energy density of 540 W h kg−1 at a power density of 600 W kg−1, and a good capacity retention of 85% after up to 160 cycles. The Fe-doping effects in V2O5 matrix with the nanorod architecture provides abundant contact with electrolyte, an increased electrical conductivity, and shortened ionic diffusion distance during electrochemical processes, facilitating overall energy-storing performance. This work provides a necessary strategy for designing next-generation high-performance energy storage devices.

MnO2@V2O5 microspheres as cathode materials for high performance aqueous rechargeable Zn-ion battery

The development of manganese dioxide (MnO2) as cathode materials in rechargeable aqueous zinc-ion batteries (ZIBs) is tremendously restricted by the dissolution of MnO2 during charge/discharge process. Herein, vanadium pentoxide (V2O5)-coated MnO2 as cathode is proposed via a facile thermal decomposition method. The V2O5 nanoparticles are coated on the MnO2 microsphere with an average diameter of 1 μ m, enhancing ion insertion/extraction kinetics and suppressing the dissolution of the cathode material during cycling. The MnO2@V2O5 microspheres exhibit a high specific capacity of 381.4 mA h g−1 at 100 mA g−1, excellent rate capability of 160.7 mAh g−1 at 1600 mA g−1 and good long-term cycling stability with 73% capacity retention after 3000 cycles at 2000 mA g−1. This study highlights the potential of Zn-ion conductor oxide coating as a strategy of improving the electrochemical performance of MnO2 in aqueous ZIBs.

New Insights into the Electrochemistry of Carbonyl- and Amino-Containing Polymers for Rechargeable Zinc–Organic Batteries

Organic electrode materials have a large variety of types and could be a replacement for metal compounds in building high-performance rechargeable Zn-ion batteries. Polymers with redox activity can...

In-situ tuning the NH4+ extraction in (NH4)2V4O9 nanosheets towards high performance aqueous zinc ion batteries

Aqueous rechargeable Zn ion batteries (ARZIBs) are investigated as a capable alternative battery technology for a large-scale energy storage system. Exploring and understanding the Zn ions storage mechanism is a significant method to adjust the Zn ion storage behavior of electrode materials. Herein, we demonstrate a phase transition of the (NH4)2V4O9 cathode material at the voltage of above 1.3 V. After the initial Zn2+ insertion/extraction process, bilayer V2O5·nH2O is observed and the interlayer spacing is enlarged, boosting the electrochemical performance of the electrode. The cathode materials show an enhanced capacity of 508 mAh g−1 at 100 mA g−1 and stable cycling performance (259 mAh g−1 after 1000 cycles at 10 A g−1, with 98.2% capacity retention). Moreover, the (NH4)2V4O9 nanosheets exhibited a remarkable specific energy density of 373.2 Wh kg−1 at a power density of 74.6 W kg−1, suggesting its potential application for the high-performance ARZIBs.

Boosting the Zn-ion transfer kinetics to stabilize the Zn metal interface for high-performance rechargeable Zn-ion batteries

An artificial SEI film based on Zn-intercalated montmorillonite was designed to tune the deposition behaviour of Zn2+ ions on the surface of Zn anode.

Redox-active zinc thiolates for low-cost aqueous rechargeable Zn-ion batteries.

Aqueous zinc-ion batteries (AZIBs) are promising candidates for large-scale electrical energy storage due to the inexpensive, safe, and non-toxic nature of zinc. One key area that requires further development is electrode materials that store Zn2+ ions with high reversibility and fast kinetics. To determine the viability of low-cost organosulfur compounds as OEMs for AZIBs, we investigate how structural modification affects electrochemical performance in Zn-thiolate complexes 1 and 2. Remarkably, modification of one thiolate in 1 to sulfide in 2 reduces the voltage hysteresis from 1.04 V to 0.15 V. While 1 exhibits negligible specific capacity due to the formation of insulating DMcT polymers, 2 delivers a capacity of 107 mA h g−1 with a primary discharge plateau at 1.1 V vs. Zn2+/Zn. Spectroscopic studies of 2 suggest a Zn2+ and H+ co-insertion mechanism with Zn2+ as the predominant charge carrier. Capacity fading in Zn-2 cells likely results from the formation of (i) soluble H+ insertion products and (ii) non-redox-active side products. Increasing electrolyte concentration and using a Nafion membrane significantly enhances the stability of 2 by suppressing H+ insertion. Our findings provide insight into the molecular design strategies to reduce the polarization potential and improve the cycling stability of the thiolate/disulfide redox couple in aqueous battery systems.

Tuning the Electrochemical Stability of Zinc Hexacyanoferrate through Manganese Substitution for Aqueous Zinc-Ion Batteries

Aqueous rechargeable Zn-ion batteries (ARZIBs) attract intensive attention as an alternative battery technology for large-scale electrochemical energy storage applications because of their low cost...

Vanadium hexacyanoferrate with two redox active sites as cathode material for aqueous Zn-ion batteries

Aqueous rechargeable Zn-ion batteries (ARZIBs) are attractive due to their low cost, high safety and environmental friendliness. However, the development of ARZIBs still faces many challenges. One of the biggest challenges is to find suitable cathode materials for reversible Zn2+ ions insertion/extraction. In this work, we synthesize a Prussian blue analogue (PBA) with a new chemical composition, vanadium hexacyanoferrate (VHCF), via a simple co-precipitation method and study its performance as a cathode material for an aqueous rechargeable Zn-ion battery. The VHCF with two electrochemical redox active sites, V and Fe, delivers a three-electron redox reaction with a capacity of 187 mA h g−1 at current density of 0.5 A g−1. Even at a current rate of 5 A g−1, VHCF can still deliver a large capacity of 122 mA h g−1. The Zn//VHCF battery also exhibits a long cycle life of 1000 cycles with excellent capacity retention of 87.8% and a high Coulombic efficiency close to 100%. During the first charging process, the cubic structure of VHCF changes to a rhombohedral phase, a structure where the Zn2+ ions can be reversibly inserted into and extracted from in subsequent cycles. The promising performances make VHCF an attractive candidate as cathode material for ARZIBs system.