Rechargeable Zn-ion Batteries Research Articles

α-MnO2@In2O3 Nanotubes as Cathode Material for Aqueous Rechargeable Zn-Ion Battery with High Electrochemical Performance

Rechargeable aqueous zinc-manganese batteries have been receiving inclusive attention due to their high energy density, low cost and environmental friendliness. However, the development of manganese dioxide as the cathode for aqueous Zn-ion batteries (ZIBs) is restricted by the speedy capacity attenuation and low rate performance. Herein, a new cathode material α-MnO2@In2O3 is proposed. After a uniform coating of In2O3 on the α-MnO2 nanotubes, the cycling stability and rate performance have all got great improvement due to the enhancement of the electrical conductivity according to the electrochemical kinetical investigation result. α-MnO2@In2O3 exhibits a high capacity of 425 mA h g−1 after 100 cycles at 100 mA g−1, and it can still maintain 115 mA h g−1 at a high current density of 2000 mA g−1 after a long-term cycling of 1300 cycles. Besides, a specific capacity of 75 mA h g−1 is attained at 3000 mA g−1 for 3000 cycles without significant decay. The overall electrochemical performance are superior to most other reported cathode materials so far. This study brings a new coating strategy of using In2O3 to the improvement of the intrinsic poor conductivity of cathode materials other than carbon coating.

Forming bubble-encapsulated double-shelled hollow spheres towards fast kinetics and superior high rate performance for aqueous rechargeable Zn-ion batteries

“Bubble-encapsulated double-shelled” hollow spheres significantly promote the fast kinetics and superior rate capability of the zinc vanadate oxide for Zn-ion batteries.

A MOF-based single-ion Zn2+ solid electrolyte leading to dendrite-free rechargeable Zn batteries

Rechargeable Zn ion battery is a promising alternative for the current portable and mobile energy storage technologies because of its good safety, low cost, and material abundance. Poor deposition reversibility with dendrite formation of Zn metal anode in aqueous electrolytes, which brings the risk of short-circuit and capacity loss (dead Zn), is one of the critical issues that plague its practical applications. To improve the performances of Zn ion batteries, a crystalline single-ion Zn2+ solid-state electrolyte (SSE) is designed based on a post-synthetic modified metal–organic framework. The SSE possesses many advantages such as high ionic conductivity of 2.1 × 10−4 S cm−1 at 30 °C, minor activation energy of 0.12 eV, high Zn2+ transference number of 0.93, along with the good mechanical and electrochemical stability. Due to the restricted and guided Zn deposition through the nanowetted Zn/SSE interface at which Zn(H2O)62+ ions are confined, excellent compatibility between Zn metal anode and the SSE is revealed, which is confirmed firmly by the stable Zn plating/stripping performance, giving rise to a homogeneous, compact, and smooth Zn deposition layer. The good properties of the SSE are further verified in VS2/Zn batteries, which deliver a reversible capacity of 125 mAh g−1 over 250 cycles at 0.2 A g−1 and a reasonable rate capability with ~40% capacity retention (vs. 0.1 A g−1) at 2 A g−1.

RETRACTED: MoS2 nanosheets with expanded interlayer spacing for rechargeable aqueous Zn-ion batteries

Abstract Recently, rechargeable Zn-ion batteries (ZIBs) have attracted incremental attention as prospective energy storage devices for grid-scale applications and flexible devices, due to their low cost, environmental benignity, high safety and unique properties of the Zn metal. However, the sustained development of high-performance ZIBs is hindered by the limited availability of cathode materials. Here, for the first time, we demonstrate MoS2 with expanded inter-layer spacing (E-MoS2) can be a promising cathode candidate for rechargeable and flexible ZIBs. By X-ray diffraction (XRD) and Raman studies, a reversible Zn2+ ion intercalation/deintercalation mechanism was revealed. The E-MoS2 electrode delivers a specific capacity of 202.6 mA h g−1 at 0.1 A g−1, a desirable energy density of 148.2 Wh kg−1 and good cycle stability with a capacity retention ratio of 98.6% over 600 cycles. By using the newly-developed starch/ polyacrylamide (PAM) based polymer electrolyte with high zinc ion conductivity, a quasi-solid Zn/E-MoS2 battery was developed, which exhibits decent electrochemical performance even under various heavy deformations, holding great potential for applications in future flexible and wearable devices.

Toward Tailorable Zn-Ion Textile Batteries with High Energy Density and Ultrafast Capability: Building High-Performance Textile Electrode in 3D Hierarchical Branched Design.

Rechargeable Zn-ion batteries are promising candidates for wearable energy storage devices. However, their performance is severely restricted by the low conductivity and inferior mass loading. Herein, a new type of the textile based electrodes with 3D hierarchical branched design is reported. Both Ni nanoparticles and carbon nanotubes are used to build conductive coatings on the textiles. The 3D hierarchical nanostructures, consisting of the vertical-aligned nanosheets and the fluffy-like small flakes, grow on the conductive textiles to form the self-supported electrodes. It ensures fast electron/ion transport and high mass loading, and maintains the structure stability during cycling. Two textile electrodes with the NiCo hydroxide and MnO2 self-branched nanostructures are constructed. Their faster kinetics, higher capacity and better rate capability than the solitary nanosheets based counterpart demonstrate the superiority of the hierarchical architecture. Moreover, the solid-state Zn-MnO2 and Zn-NiCo batteries are fabricated based on the textile electrodes and the polymer electrolytes. The high energy density, superior power density and good long-term cycling stability confirm their excellent energy storage ability and fast charge/discharge capability. Particularly, the high safety under various conditions enable them promising candidates for wearable electronics.

Graphene-Boosted, High-Performance Aqueous Zn-Ion Battery.

Given their low cost and eco-friendliness, rechargeable Zn-ion batteries (ZIBs) have received increasing attention as a device with great potential for large-scale energy storage. However, the development of ZIBs with high capacities and long lifespans is challenging because of the dendritic growth of Zn and the absence of suitable cathode materials. Herein, we report a novel rechargeable aqueous Zn-ion battery (AZIB) that consist of Zn coated with reduced graphene oxide as the anode and V3O7·H2O/rGO composite as the cathode. The new AZIB exhibits excellent cycle stability with a high capacity retention of 79% after 1000 cycles. Moreover, it can deliver a high power density of 8400 W kg-1 at 77 W h kg-1 and a high energy density of 186 W h kg-1 at 216 W kg-1, and the former is higher than those of previously reported AZIBs. Our work provides a new perspective in developing rechargeable ZIBs and would greatly accelerate the practical applications of rechargeable ZIBs.

Oxygen-Vacancy and Surface Modulation of Ultrathin Nickel Cobaltite Nanosheets as a High-Energy Cathode for Advanced Zn-Ion Batteries.

The development of high-capacity, Earth-abundant, and stable cathode materials for robust aqueous Zn-ion batteries is an ongoing challenge. Herein, ultrathin nickel cobaltite (NiCo2 O4 ) nanosheets with enriched oxygen vacancies and surface phosphate ions (P-NiCo2 O4-x ) are reported as a new high-energy-density cathode material for rechargeable Zn-ion batteries. The oxygen-vacancy and surface phosphate-ion modulation are achieved by annealing the pristine NiCo2 O4 nanosheets using a simple phosphating process. Benefiting from the merits of substantially improved electrical conductivity and increased concentration of active sites, the optimized P-NiCo2 O4-x nanosheet electrode delivers remarkable capacity (309.2 mAh g-1 at 6.0 A g-1 ) and extraordinary rate performance (64% capacity retention at 60.4 A g-1 ). Moreover, based on the P-NiCo2 O4-x cathode, our fabricated P-NiCo2 O4-x //Zn battery presents an impressive specific capacity of 361.3 mAh g-1 at the high current density of 3.0 A g-1 in an alkaline electrolyte. Furthermore, extremely high energy density (616.5 Wh kg-1 ) and power density (30.2 kW kg-1 ) are also achieved, which outperforms most of the previously reported aqueous Zn-ion batteries. This ultrafast and high-energy aqueous Zn-ion battery is promising for widespread application to electric vehicles and intelligent devices.

Reaction Mechanisms for Long Life and Ultra-High Power Rechargeable Zn Ion Batteries

Rechargeable aqueous Zn-ion batteries (ZIBs) are very promising for large-scale grid energy storage applications owing to their low cost, environmentally benign constituent elements, excellent safety, and relatively high-energy density. Their usage, however, is largely hampered by their fast capacity fade. The cycle stability seems to be highly rate-dependent, which poses an additional challenge, but can also play a pivotal role in uncovering the reaction mechanisms. The complexity of the reactions in this electrochmical system has resulted in long-standing ambiguity of the chemical pathways of Zn/MnO2 rechargable battery system, and has led to many controversies with regard to their nature. In this talk, we present a combined experimental and theoretical study of Zn/MnO2 cells. We found that both H+/Zn2+ intercalation and conversion reactions occur at different voltages, and that the rapid capacity fading can clearly be ascribed to the rate-limiting and irreversible conversion reactions at a lower voltage. By avoiding the irreversible conversion reactions at ~ 1.26 V, we successfully demonstrate ultra-high power and long-life Zn/MnO2 cells which, after 1000 cycles, maintain an energy density of ~ 231 Wh kg-1 and 105 Wh kg-1 at a power density of ~ 4 kW kg-1 (9C, ~ 3.1 A g-1) and ~ 15 kW kg-1 (30 C, ~ 10.3 A g-1), respectively. The excellent cycle stability and power capability are superior to most reported ZIBs or even some lithium-ion batteries. The results establish accurate electrochemical reaction mechanisms and kinetics for Zn/MnO2, and identify the interplay of the voltage window and rate determining factors for achieving excellent cycle life.

Na2V6O16·3H2O Barnesite Nanorod: An Open Door to Display a Stable and High Energy for Aqueous Rechargeable Zn-Ion Batteries as Cathodes.

Owing to their safety and low cost, aqueous rechargeable Zn-ion batteries (ARZIBs) are currently more feasible for grid-scale applications, as compared to their alkali counterparts such as lithium- and sodium-ion batteries (LIBs and SIBs), for both aqueous and nonaqueous systems. However, the materials used in ARZIBs have a poor rate capability and inadequate cycle lifespan, serving as a major handicap for long-term storage applications. Here, we report vanadium-based Na2V6O16·3H2O nanorods employed as a positive electrode for ARZIBs, which display superior electrochemical Zn storage properties. A reversible Zn2+-ion (de)intercalation reaction describing the storage mechanism is revealed using the in situ synchrotron X-ray diffraction technique. This cathode material delivers a very high rate capability and high capacity retention of more than 80% over 1000 cycles, at a current rate of 40C (1C = 361 mA g-1). The battery offers a specific energy of 90 W h kg-1 at a specific power of 15.8 KW kg-1, enlightening the material advantages for an eco-friendly atmosphere.

An adaptive and stable bio-electrolyte for rechargeable Zn-ion batteries

An adaptive and stable gum bio-electrolyte was developed, which enabled Zn-ion batteries that have very competitive performances in terms of capacity, energy density, power density, rate capability and cyclability.

Aqueous rechargeable Zn-ion batteries: an imperishable and high-energy Zn2V2O7 nanowire cathode through intercalation regulation

α-Zn2V2O7 nanowire is utilized as cathode for aqueous Zn-ions energy storage application. This cathode is sustained a high reversible capacity of 138 mA h g−1 after 1000 cycles and displays a high specific energy, added advantage for aqueous battery system.

A flexible rechargeable zinc-ion wire-shaped battery with shape memory function

A flexible wire-shaped rechargeable Zn-ion battery with shape memory function was fabricated, delivering decent performances and good recoverability to mechanical deformation.

K2V6O16·2.7H2O nanorod cathode: an advanced intercalation system for high energy aqueous rechargeable Zn-ion batteries

Layered K2V6O16·2.7H2O nanorod cathode, utilized for aqueous rechargeable Zn-ion batteries, displays high reversible capacities, exceptional rate capabilities and long cycle-span of 700 (altering three different current densities) and 500 (~82% capacity retention at 6 A g−1) cycles.

Combining Battery-like and Pseudocapacitive Charge Storage in 3D MnOx–Carbon Electrode Architectures for Zinc-Ion Cells

The ability of manganese oxides to exhibit charge-storage behavior characteristic of either batteries or electrochemical capacitors (ECs) offers an intriguing opportunity to design electrode materials that innately deliver both high power and high capacity. We previously demonstrated that lamellar birnessite-type MnOx, when expressed in carbon nanofoam–based electrode architectures (MnOx@CNF), amplifies charge storage by pseudocapacitance in aqueous electrolytes (e.g., Na2SO4; Li2SO4). Herein, we extend the functionality of these established electrode materials by varying the ionic composition of the electrolyte in which they are cycled. For example, cycling MnOx/C nanofoam electrodes in aqueous 1 M ZnSO4 yields battery-like voltammetric features reminiscent of those previously reported for “rechargeable Zn-ion batteries.” When cycling in mixed Na2SO4:ZnSO4 electrolytes, we retain Zn2+ redox peaks, but now superimposed on a pseudocapacitive background arising from the presence of Na2SO4. The Zn2+ redox provides high capacity (up to 230 mAh g–1 normalized to MnOx) at low rates (<5 mV s–1), while pseudocapacitance mechanisms take over at high rates to mitigate the effects of slow kinetics for Zn2+ insertion. Fundamental electrochemical properties are established using a three-electrode half-cell configuration. We apply peak-current kinetic analyses (for CV data) and AC impedance to deconvolve the complex mechanisms that give rise to battery-like and pseudocapacitive charge-storage features. On the basis of three-electrode studies, we down-select electrolyte compositions for testing MnOx@CNF, paired against Zn metal, in two-electrode Swagelok cells that are subjected to galvanostatic cycling at challenging C-rates (1C–20C).

Highly Reversible Zinc-Ion Intercalation into Chevrel Phase Mo6S8 Nanocubes and Applications for Advanced Zinc-Ion Batteries.

This work describes the synthesis of Chevrel phase Mo6S8 nanocubes and its application as the anode material for rechargeable Zn-ion batteries. Mo6S8 can host Zn(2+) ions reversibly in both aqueous and nonaqueous electrolytes with specific capacities around 90 mAh/g, and exhibited remarkable intercalation kinetics and cyclic stability. In addition, we assembled full cells by integrating Mo6S8 anodes with zinc-polyiodide (I(-)/I3(-))-based catholytes, and demonstrated that such full cells were also able to deliver outstanding rate performance and cyclic stability. This first demonstration of a zinc-intercalating anode could inspire the design of advanced Zn-ion batteries.