Flexible Zinc-Manganese Dioxide Alkaline Batteries Based on Kelp Electrolytes

Flexible energy-storage devices play a critical role in the development of portable, flexible and wearable electronics. In addition, biological materials including plants or plant-based materials are known for their safety, biodegradability, biocompatibility, environmental benignancy, and low cost. With respect to these advances, a flexible alkaline zinc-manganese dioxide (Zn-MnO2) battery is fabricated with a kelp-based electrolyte in this study. To the best of our knowledge, pure kelp is utilized as a semi-solid electrolyte for flexible Zn-MnO2 alkaline batteries for the first time, with which the as-assembled battery exhibited a specific capacity of 60 mA·h and could discharge for 120 h. Furthermore, the as-assembled Zn-MnO2 battery can be bent into a ring-shape and power a light-emitting diode screen, showing promising potential for the practical application in the future flexible, portable and biodegradable electronic devices.

Recent advances in flexible alkaline zinc-based batteries:Materials,structures,and perspectives

The development of wearable electronic systems has generated increasing demand for flexible power sources.Alkaline zinc(Zn)-based batteries,as one of the most mature energy storage technologies,have been considered as a promising power source owing to their exceptional safety,low costs,and outstanding electrochemical performance.However,the conventional alkaline Zn-based battery systems face many challenges associated with electrodes and electrolytes,causing low capacity,poor cycle life,and inferior mechanical performance.Recent advances in materials and structure design have enabled the revisitation of the alkaline Zn-based battery technology for applications in flexible electronics.Herein,we summarize the up-to-date works in flexible alkaline Zn-based batteries and analyze the strategies employed to improve battery performance.Firstly,we introduce the three most reported cathode materials(including Ag-based,Ni-based,and Co-based materials)for flexible alkaline Zn-based batteries.Then,challenges and modifications in battery anodes are investigated.Thirdly,the recently advanced gel electrolytes are introduced from their properties,functions as well as advanced fabrications.Finally,recent works and the advantages of sandwich-type,fiber-type and thin film-type flexible batteries are summarized and compared.This review provides insights and guidance for the design of high-performance flexible Zn-based batteries for next-generation electronics.

Design strategy and comprehensive performance assessment towards Zn anode for alkaline rechargeable batteries

Alkaline Zn-based primary batteries have been commercialized in the past decades.However,their success has not been extended to secondary batteries due to the poor cycle reversibility of Zn anodes.Although some research has been conducted on alkaline Zn anodes,their performance is still far from commercial requirements.A variety of degradation mechanisms,including passivation,dendrites,morphological changes,and hydrogen precipitation,are claimed responsible for the failure of alkaline Zn metal anodes.What’s worse,these constraints always interact with each other,which leads to a single strategy being unable to suppress all the issues.Therefore,a comprehensive evaluation of the positive and negative effects of various strategies on performance is important to promote the commercialization of alkaline Zn batteries.Herein,the recent progress and performance of improvement strategies for Zn anode in alkaline conditions are reviewed systematically.First,the principles and challenges of alkaline Zn anodes are briefly analyzed.Then,various design strategies for alkaline Zn anodes from the perspectives of ion and electron regulation are highlighted.Last,through a comprehensive summary of various performance parameters,the advantages and disadvantages of different strategies are compared and evaluated.On the basis of this assessment,we aim to provide more insights into the anode design of high-performance alkaline rechargeable Zn batteries.

Graphitic Carbon Quantum Dots Modified Nickel Cobalt Sulfide as Cathode Materials for Alkaline Aqueous Batteries

Carbon quantum dots(CQDs)as a new class of emerging materials have gradually drawn researchers’concern in recent years.In this work,the graphitic CQDs are prepared through a scalable approach,achieving a high yield with more than 50%.The obtained CQDs are further used as structure-directing and conductive agents to synthesize novel N,S-CQDs/NiCo2S4 composite cathode materials,manifesting the enhanced electrochemical properties resulted from the synergistic effect of highly conductive N,S-codoped CQDs offering fast electronic transport and unique micro-/nanostructured NiCo2S4 microspheres with Faradaic redox characteristic contributing large capacity.Moreover,the nitrogen-doped reduced graphene oxide(N-rGO)/Fe2O3 composite anode materials exhibit ultrahigh specific capacity as well as significantly improved rate property and cycle performance originating from the high-capacity prism-like Fe2O3 hexahedrons tightly wrapped by highly conductive N-rGO.A novel alkaline aqueous battery assembled by these materials displays a specific energy(50.2 Wh kg^−1),ultrahigh specific power(9.7 kW kg^−1)and excellent cycling performance with 91.5%of capacity retention at 3 A g^−1 for 5000 cycles.The present research offers a valuable guidance for the exploitation of advanced energy storage devices by the rational design and selection of battery/capacitive composite materials.

Manganese Dioxide with High Specific Surface Area for Alkaline Battery

The authors reported a facile method for the synthesis of manganese dioxide without any template and catalyst at a low-temperature. The prepared sample was characterized with X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Brunauer-Emmett-Teller（BET） surface analysis, Fourier transform infrared（FTIR） spectrometry, cyclic voltammetry, alternative current（AC） impedance test and battery discharge test. It is found that the prepared sample belongs to α-MnO2 and has a microsphere morphology and a large BET surface area. The electrochemical characterization indicates that the prepared sample displays a larger electrochemical capacitance than the commercial electrolytic manganese dioxides（EMD） in Na2SO4 solution, and exhibits larger discharge capacity than EMD, especially at a high rate discharge condition when it is used as cathode of alkaline Zn/MnO2 battery.

ZnO Additive Boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn Batteries

Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish deposition reaction kinetics of manganese oxide during the charge process and short cycle life. We show that, incorporating ZnO electrolyte additive can form a neutral and highly viscous gel-like electrolyte and render a new form of electrolytic Zn–Mn batteries with significantly improved charging capabilities. Specifically, the ZnO gel-like electrolyte activates the zinc sulfate hydroxide hydrate assisted Mn^(2+) deposition reaction and induces phase and structure change of the deposited manganese oxide(Zn_(2)Mn_(3)O_8·H_(2)O nanorods array), resulting in a significant enhancement of the charge capability and discharge efficiency. The charge capacity increases to 2.5 mAh cm^(-2) after 1 h constant-voltage charging at 2.0 V vs. Zn/Zn^(2+), and the capacity can retain for up to 2000 cycles with negligible attenuation. This research lays the foundation for the advancement of electrolytic Zn–Mn batteries with enhanced charging capability.

Reductive atmospheric acid leaching of spent alkaline batteries in H_2SO_4/Na_2SO_3 solutions

This work studies the optimum reductive leaching process for manganese and zinc recovery from spent alkaline battery paste. The effects of reducing agents, acid concentration, pulp density, reaction temperature, and leaching time on the dissolution of manganese and zinc were investigated in detail. Manganese dissolution by reductive acidic media is an intermediate-controlled process with an activation energy of 12.28 kJ＇mo1-1. After being leached, manganese and zinc were selectively precipitated with sodium hydroxide. The zinc was entirely con- verted into zincate （Zn（OH）42-） ions and thus did not co-precipitate with manganese hydroxide during this treatment （2.0 M NaOH, 90 min, 200 r/rain, pH 〉 13）. After the manganese was removed from the solution, the Zn（OH）4^2- was precipitated as zinc sulfate in the presence of sulfuric acid. The results indicated that this process could be effective in recovering manganese and zinc from alkaline batteries.

Effect of magnesium on the aluminothermic reduction rate of zinc oxide obtained from spent alkaline battery anodes for the preparation of Al–Zn–Mg alloys

The aluminothermic reduction of zinc oxide（ZnO） from alkaline battery anodes using molten Al may be a good option for the elaboration of secondary 7000-series alloys. This process is affected by the initial content of Mg within molten Al, which decreases the surface tension of the molten metal and conversely increases the wettability of ZnO particles. The effect of initial Mg concentration on the aluminothermic reduction rate of ZnO was analyzed at the following values： 0.90wt%, 1.20wt%, 4.00t%, 4.25wt%, and 4.40wt%. The ZnO particles were incorporated by mechanical agitation using a graphite paddle inside a bath of molten Al maintained at a constant temperature of 1123 K and at a constant agitation speed of 250 r/min, the treatment time was 240 min and the ZnO particle size was 450？500 mesh. The results show an increase in Zn concentration in the prepared alloys up to 5.43wt% for the highest initial concentration of Mg. The reaction products obtained were characterized by scanning electron microscopy and X-ray diffraction, and the efficiency of the reaction was measured on the basis of the different concentrations of Mg studied.

Dendritic Nanostructured Waste Copper Wires for High-Energy Alkaline Battery

Rechargeable alkaline batteries(RABs)have received remarkable attention in the past decade for their high energy,low cost,safe operation,facile manufacture,and ecofriendly nature.To date,expensive electrode materials and current collectors were predominantly applied for RABs,which have limited their real-world efficacy.In the present work,we propose a scalable process to utilize electronic waste(e-waste)Cu wires as a cost-effective current collector for high-energy wire-type RABs.Initially,the vertically aligned CuO nanowires were prepared over the waste Cu wires via in situ alkaline corrosion.Then,both atomiclayer-deposited NiO and NiCo-hydroxide were applied to the CuO nanowires to form a uniform dendritic-structured NiCo-hydroxide/NiO/CuO/Cu electrode.When the prepared dendritic-structured electrode was applied to the RAB,it showed excellent electrochemical features,namely high-energy-density(82.42 Wh kg−1),excellent specific capacity(219 mAh g−1),and long-term cycling stability(94%capacity retention over 5000 cycles).The presented approach and material meet the requirements of a cost-effective,abundant,and highly efficient electrode for advanced eco-friendly RABs.More importantly,the present method provides an efficient path to recycle e-waste for value-added energy storage applications.

Bismuth Oxide Selenium/Graphene Oxide Composites:Toward High-Performance Electrodes for Aqueous Alkaline Battery

Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.

Determination of the density of zinc powders for alkaline battery

The density of zinc powder for alkaline battery was determined using a pyknometer.The results showed that powders made before the end of 2003 could reach relative densities above 99% of the theoretical density.Investigating the relative volume swelling of electrolysed gels of zinc powders,no evident relation between swelling and pyknometer density was found.

LR6,LR03 Alkaline Hige Energy Zinc and Manganese Battery

TheNanfuBatteryCo.Ltd.inNanpingFuiian,isChina'sbiggestproducerandexporterofairlinezincandmanganesebatteries.NanfubrandandChaolibrandLR6andLR03alkalinehighenergyzinceandmanganesebatterieshavealargevolume,bigcurrent,longlife,andareleakproofandsafe,andc...

Perspective of alkaline zinc-based flow batteries

Energy storage technologies have been identified as the key in constructing new electric power systems and achieving carbon neutrality,as they can absorb and smooth the renewables-generated electricity.Alkaline zinc-based flow batteries are well suitable for stationary energy storage applications,since they feature the advantages of high safety,high cell voltage and low cost.Currently,many alkaline zinc-based flow batteries have been proposed and developed,e.g.,the alkaline zinc–iron flow battery and alkaline zinc–nickel flow battery.Their development and application are closely related to advanced materials and battery configurations.In this perspective,we will first provide a brief introduction and discussion of alkaline zinc-based flow batteries.Then we focus on these batteries from the perspective of their current status,challenges and prospects.The bottlenecks for these batteries are briefly analyzed.Combined with the practical requirements and development trends of alkaline zinc-based flow battery technologies,their future development and research direction will be summarized.

Long-lifespan aqueous alkaline and acidic batteries enabled by redox conjugated covalent organic polymer anodes

Herein,we introduce a redox conjugated covalent organic polymer(p-HATN,HATN=hexaazatrinaphthylene)anode bearing HATN species for long-lifespan aqueous alkaline and acidic batteries.The p-HATN features intriguing superhydrophilicity and unique wide pH adaptability,while the conjugated network and amorphous cross-linked structure further endow p-HATN with improved electron transport,facile ion diffusion and superior acid-alkali tolerability.As a result,p-HATN exhibits fast surface-controlled redox activity and superior stability for K^(+)and H^(+)ions storage with remarkable capacity retentions in three-electrode cells(88%capacity retention in 13 M KOH over 30000 cycles;nearly 100%capacity retention in 0.5 M H_(2)SO_(4)over 54000 cycles).Moreover,the assembled p-HATN//Ni(OH)_(2)cell with 13 M KOH and p-HATN//PbO_(2)cell with 0.5 M H_(2)SO_(4)also achieve ca-pacity retentions of 83%retention over 55000 cycles and 92%over 15000 cycles,respectively,outperforming most similar systems.This work sheds light on the rational design of advanced polymer anodes for long-lifespan alkaline and acidic batteries.

Alkaline zinc-based flow battery: chemical stability, morphological evolution, and performance of zinc electrode with ionic liquid

Zinc-based flow battery is an energy storage technology with good application prospects because of its advantages of abundant raw materials,low cost,and environmental friendliness.The chemical stability of zinc electrodes exposed to electrolyte is a very important issue for zinc-based batteries.This paper reports on details of chemical stability of the zinc metal exposed to a series of solutions,as well as the relationship between the morphological evolution of zinc electrodes and their properties in an alkaline medium.Chemical corrosion of zinc electrodes by the electrolyte will change their surface morphology.However,we observed that chemical corrosion is not the main contributor to the evolution of zinc electrode surface morphology,but the main contributor is the Zn/Zn^(2+)electrode process.The morphological evolution of zinc electrodes was controlled by using ionic liquids,1-ethyl-3-methylimidazolium acetate(EMIA),and 1-propylsulfonic-3-methylimidazolium tosylate(PSMIT),and the electrode performance was recorded during the morphological evolution process.It was observed that the reversible change of zinc electrode morphology was accompanied by better electrode performance.

Comparison of Alkaline Treatment of Lead Contaminated Wastewater Using Lime and Sodium Hydroxide

A lead-acid storage battery manufacturing industry in India produces several thousand liters of lead con-taminated acidic wastewater on a daily basis and uses hydrated lime to render the lead-contaminated acidic wastewater alkaline (pH = 8.0). Alkaline treatment of the acidic wastewater with lime though a cost-effective method, generates copious amount of lead-contaminated gypsum sludge. Other alkali agents such as sodium hydroxide, sodium carbonate and dolomite are also used for alkali treatment of the acid wastewaters. The present paper compares the relative efficiency of hydrated lime and 0.05 M to 1 M NaOH solutions with re-spect to 1) amounts of sludge produced, 2) immobilization of the soluble lead in the acidic wastewater (AWW) and 3) increase in TDS (total dissolved solids) levels upon treatment of AWW with NaOH solutions and lime. The study also performs equilibrium speciation upon alkaline treatment of AWW with lime and NaOH (sodium hydroxide) solutions using the Visual MINTEQ program to understand the chemical reac-tions occurring during treatment process.

Hetero-interfacial nickel nitride/vanadium oxynitride porous nanosheets as trifunctional electrodes for HER,OER and sodium ion batteries

The development of single electrode with multifunctional purposes for electrochemical devices remains a symbolic challenge in recent technology.This work explores interfacially-rich transition metal nitride hybrid that consist of nickel nitride and vanadium oxynitride(VO_(0.26)N_(0.52))on robust carbon fiber(denoted CF/Ni_(3)N/VON)as trifunctional electrode for hydrogen evolution reaction(HER),oxygen evolution reaction(OER),and sodium ion batteries(SIBs).The as-prepared CF/Ni_(3)N/VON exhibits low HER overpotential of 48 m V@10 m A cm^(-2),OER overpotential of 287 m V@10 m A cm^(-2),and sodium-ion anode storage reversible capacity of 555 m A h g^(-1)@0.2 C.Theoretical analyses reveal that the Ni_(3)N effectively facilitates hydrogen desorption for HER,increases the electrical conductivity for OER,and promotes the Na-ion storage intercalation process,while the VON substantially elevates the water dissociation kinetics for HER,accelerates the adsorption of OH*intermediate for OER and enhances the Na-ion surface adsorption storage process.Owing to the excellent HER and OER performances of the CF/Ni_(3)N/VON electrode,an overall water splitting device denoted as CF/Ni_(3)N/VON//CF/Ni_(3)N/VON was not only assembled showing an operating voltage of 1.63 V at current density of 10 m A cm^(-2)but was also successfully self-powered by the assembled CF/Ni_(3)N/VON//CF/Na_(3)V_(2)(PO_(4))_(3) flexible sodium ion battery.This work will contribute to the development of efficient and cost-effective flexible integrated electrochemical energy devices.

基于活性炭‖Na_(0.44)MnO_(2)的低成本、高倍率和长寿命碱性钠离子电池电容器

水系钠离子电池电容器具有成本低、功率大、安全性好等优点,是下一代大规模储能系统的理想选择之一。本文采用Na_(0.44)MnO_(2)正极、活性炭(AC)负极、6mol·L^(-1)NaOH电解液和廉价的不锈钢集流体构建了可充电碱性钠离子电池电容器。由于Na_(0.44)MnO_(2)正极在碱性电解液中具有较高的过充耐受性,通过首次充电时的原位过充预活化过程可以解决半钠化Na_(0.44)MnO_(2)正极和AC负极初始库伦效率低的缺点。因此,AC‖Na_(0.44)MnO_(2)可充电碱性钠离子电池电容器具有优异的电化学性能,在功率密度为85 W·kg^(-1)时,能量密度达26.6 Wh·kg^(-1),循环10000次后容量保持率为89%。同时,在50℃的高温和-20℃的低温也具有良好的电化学性能。这些结果表明AC‖Na_(0.44)MnO_(2)可充电碱性钠离子电池电容器具备应用于大规模储能的潜力。

强力磁铁在碱性锌锰电池生产线上的应用

利用钢壳是磁性材料的特性,将强力磁铁应用于高速自动化LR6碱性锌锰(碱锰)电池生产线,以解决钢壳在运输过程中变形的问题。以LR12电池集流体插入机改造为例,比较真空吸取集流体和强力磁铁吸取集流体两种方式的优劣。实践证明,使用强力磁铁吸取集流体,不仅提高了5%的设备运转率和2%的产品合格率,而且节省了维修费用。

锰正极在二次锌锰电池中的研究进展及前景

可充电锌基电池具有成本低、安全性好和比能量高等特点。MnO_(2)及其复合物由于成本低、无毒环保,且具有多晶型、结构可控、高孔隙率等特性,被广泛应用于二次锌锰电池的正极。使用传统碱性电解液的电池,循环寿命短,难以实现多次循环。近年来,含锌离子、锰离子的中性电解液的使用,提高了锌锰电池的可充性能。在介绍二次锌锰电池原理的基础上,阐述碱性电解液和中性电解液体系对电池的影响,对锰正极添加剂、纳米材料的开发、电解液、高导电碳基复合材料应用等方面开展总结和讨论。探讨抑制不可逆相的生成和促进反应向生成可逆相的途径,提出合理的思路,为高性能可充电锌基电池研究提供指导。