二氧化锰电池

Although alkaline zinc-manganese dioxide batteries have dominated the primary battery applications, it is challenging to make them rechargeable. Here we report a high-performance rechargeable zinc-manganese dioxide system with an aqueous mild-acidic zinc triflate electrolyte. We demonstrate that the tunnel structured manganese dioxide polymorphs undergo a phase transition to layered zinc-buserite on first discharging, thus allowing subsequent intercalation of zinc cations in the latter structure. Based on this electrode mechanism, we formulate an aqueous zinc/manganese triflate electrolyte that enables the formation of a protective porous manganese oxide layer. The cathode exhibits a high reversible capacity of 225 mAh g−1 and long-term cyclability with 94% capacity retention over 2000 cycles. Remarkably, the pouch zinc-manganese dioxide battery delivers a total energy density of 75.2 Wh kg−1. As a result of the superior battery performance, the high safety of aqueous electrolyte, the facile cell assembly and the cost benefit of the source materials, this zinc-manganese dioxide system is believed to be promising for large-scale energy storage applications. The development of rechargeable aqueous zinc batteries are challenging but promising for energy storage applications. With a mild-acidic triflate electrolyte, here the authors show a high-performance Zn-MnO2 battery in which the MnO2 cathode undergoes Zn2+ (de)intercalation.

The development of advanced cathode materials for zinc-ion batteries (ZIBs) is a critical step in building large-scale green energy conversion and storage systems in the future. Manganese dioxide is one of the most well-studied cathode materials for zinc-ion batteries due to its wide range of crystal forms, cost-effectiveness, and well-established synthesis processes. This review describes the recent research progress of manganese dioxide-based ZIBs, and the reaction mechanism, electrochemical performance, and challenges of manganese dioxide-based ZIBs materials are systematically introduced. Optimization strategies for high-performance manganese dioxide-based materials for ZIBs with different crystal forms, nanostructures, morphologies, and compositions are discussed. Finally, the current challenges and future research directions of manganese dioxide-based cathodes in ZIBs are envisaged.

In this paper, we propose the design of a family of hydrogel electrolytes that featuring freezing resistance, flexibility, safety, superior ionic conductivity and long-term stability to realize anti-freezing flexible aqueous batteries.

As the world moves towards sustainable and renewable energy sources, there is a need for reliable energy storage systems. A good candidate for such an application could be to improve secondary aqueous zinc–manganese dioxide (Zn-MnO2) batteries. For this reason, different aqueous Zn-MnO2 battery technologies are discussed in this short review, focusing on how electrolytes with different pH affect the battery. Improvements and achievements in alkaline aqueous Zn-MnO2 batteries the recent years have been briefly reviewed. Additionally, mild to acidic aqueous electrolyte employment in Zn-MnO2 batteries has been described, acknowledging their potential success, as such a battery design can increase the potential by up to 2 V. However, we have also recognized a novel battery electrolyte type that could increase even more scientific interest in aqueous Zn-MnO2 batteries. Consisting of an alkaline electrolyte in the anode compartment and an acidic electrolyte in the cathode compartment, this dual (amphoteric) electrolyte system permits the extension of the battery cell potential above 2 V without water decomposition. In addition, papers describing pH immobilization in aqueous zinc–manganese compound batteries and the achieved results are reported and discussed.

Aqueous zinc‐ion batteries (AZIBs) are regarded as promising electrochemical energy storage devices owing to its low cost, intrinsic safety, abundant zinc reserves, and ideal specific capacity. Compared with other cathode materials, manganese dioxide with high voltage, environmental protection, and high theoretical specific capacity receives considerable attention. However, the problems of structural instability, manganese dissolution, and poor electrical conductivity make the exploration of high‐performance manganese dioxide still a great challenge and impede its practical applications. Besides, zinc storage mechanisms involved are complex and somewhat controversial. To address these issues, tremendous efforts, such as surface engineering, heteroatoms doping, defect engineering, electrolyte modification, and some advanced characterization technologies, have been devoted to improving its electrochemical performance and illustrating zinc storage mechanism. In this review, we particularly focus on the classification of manganese dioxide based on crystal structures, zinc ions storage mechanisms, the existing challenges, and corresponding optimization strategies as well as structure–performance relationship. In the final section, the application perspectives of manganese oxide cathode materials in AZIBs are prospected.

Rechargeable aqueous Zn–MnO 2 technology combines one of the oldest battery chemistries with favourable sustainability characteristics, including safety, cost and environmental …

Aqueous rechargeable zinc–manganese dioxide batteries show great promise for large‐scale energy storage due to their use of environmentally friendly, abundant, and rechargeable Zn metal anodes and MnO2 cathodes. In the literature various intercalation and conversion reaction mechanisms in MnO2 have been reported, but it is not clear how these mechanisms can be simultaneously manipulated to improve the charge storage and transport properties. A systematical study to understand the charge storage mechanisms in a layered δ‐MnO2 cathode is reported. An electrolyte‐dependent reaction mechanism in δ‐MnO2 is identified. Nondiffusion controlled Zn2+ intercalation in bulky δ‐MnO2 and control of H+ conversion reaction pathways over a wide C‐rate charge–discharge range facilitate high rate performance of the δ‐MnO2 cathode without sacrificing the energy density in optimal electrolytes. The Zn‐δ‐MnO2 system delivers a discharge capacity of 136.9 mAh g−1 at 20 C and capacity retention of 93% over 4000 cycles with this joint charge storage mechanism. This study opens a new gateway for the design of high‐rate electrode materials by manipulating the effective redox reactions in electrode materials for rechargeable batteries.

… -activated battery [1… manganese dioxide as an environmentally friendly alternative to CuCl, to determine the differences between the batteries and to develop an optimized MnO2 battery. …

Rechargeable zinc–manganese dioxide batteries that use mild aqueous electrolytes are attracting extensive attention due to high energy density and environmental friendliness. Unfortunately, manganese dioxide suffers from substantial phase changes (e.g., from initial α-, β-, or γ-phase to a layered structure and subsequent structural collapse) during cycling, leading to very poor stability at high charge/discharge depth. Herein, cyclability is improved by the design of a polyaniline-intercalated layered manganese dioxide, in which the polymer-strengthened layered structure and nanoscale size of manganese dioxide serves to eliminate phase changes and facilitate charge storage. Accordingly, an unprecedented stability of 200 cycles with at a high capacity of 280 mA h g−1 (i.e., 90% utilization of the theoretical capacity of manganese dioxide) is achieved, as well as a long-term stability of 5000 cycles at a utilization of 40%. The encouraging performance sheds light on the design of advanced cathodes for aqueous zinc-ion batteries. Zn-MnO2 batteries offer high energy density, but phase changes that lead to poor cathode stability hinder development of rechargeable versions. Here the authors report structurally reinforced polyaniline-intercalated MnO2 nanolayers that boost performance by eliminating phase transformation.

Abstract Aqueous rechargeable zinc-manganese dioxide batteries have attracted extensive attention due to their high energy density, low cost, and environmental friendliness. However, the crystalline MnO2 polymorphs suffer from substantial phase changes upon cycling, leading to structural collapse and poor long-term cycling performance. Here, a highly reversible amorphous manganese dioxide with structural defects is reported as the cathode for aqueous rechargeable zinc-ion batteries (ARZIBs). Because of the existence of the abundant structural defects and intrinsic isotropic nature, the A-MnO2-δ exhibits significant pseudocapacitive contribution and facilitated reaction kinetics. As expected, the A-MnO2-δ delivers a high specific capacity of 301 mAh g−1 at 100 mA g−1 and long cycle-life with a capacity retention of 78% over 1000 cycles at 1 A g−1, which is better than its crystalline counterparts. In addition, a reversible H+ and Zn2+ two-step insertion storage mechanism of the A-MnO2-δ electrode is demonstrated. This study not only suggests that amorphous manganese dioxide can serve as a stable cathode for ARZIBs but also provides significant guidance to realize other high-capacity and long-lifespan aqueous batteries by using the amorphous materials.

… batteries have relatively low operating voltage, resulting in low energy density. Second, most aqueous batteries … Alkaline zinc–manganese batteries have long been commercialized, but …

… Manganese has an added advantage in that it can support … Manganese dioxide is also used as the positive active (cathode) material in Leclanche and alkaline manganese batteries [5], …

Summary Rechargeable aqueous Zn/manganese dioxide (Zn/MnO2) batteries are attractive energy storage technology owing to their merits of low cost, high safety, and environmental friendliness. However, the β-MnO2 cathode is still plagued by the sluggish ion insertion kinetics due to the relatively narrow tunneled pathway. Furthermore, the energy storage mechanism is under debate as well. Here, β-MnO2 cathode with enhanced ion insertion kinetics is introduced by the efficient oxygen defect engineering strategy. Density functional theory computations show that the β-MnO2 host structure is more likely for H+ insertion rather than Zn2+, and the introduction of oxygen defects will facilitate the insertion of H+ into β-MnO2. This theoretical conjecture is confirmed by the capacity of 302 mA h g−1 and capacity retention of 94% after 300 cycles in the assembled aqueous Zn/β-MnO2 cell. These results highlight the potentials of defect engineering as a strategy of improving the electrochemical performance of β-MnO2 in aqueous rechargeable batteries.

… cell only the first electron of the manganese dioxide is allowed to be discharged. The … proton-insertion path and fourvalent manganese dioxide is formally reduced to Mn01,5, ie: …

Although there are many studies on the preparation and electrochemical properties of the different crystal forms of manganese dioxide, there are few studies on their preparation by a liquid phase method and the influence of their physical and chemical properties on their electrochemical performance. In this paper, five crystal forms of manganese dioxide were prepared by using manganese sulfate as a manganese source and the difference of their physical and chemical properties was studied by phase morphology, specific surface area, pore size, pore volume, particle size and surface structure. The different crystal forms of manganese dioxide were prepared as electrode materials, and their specific capacitance composition was obtained by performing CV and EIS in a three-electrode system, introducing kinetic calculation and analyzing the principle of electrolyte ions in the electrode reaction process. The results show that δ-MnO2 has the largest specific capacitance due to its layered crystal structure, large specific surface area, abundant structural oxygen vacancies and interlayer bound water, and its capacity is mainly controlled by capacitance. Although the tunnel of the γ-MnO2 crystal structure is small, its large specific surface area, large pore volume and small particle size make it have a specific capacitance that is only inferior to δ-MnO2, and the diffusion contribution in the capacity accounts for nearly half, indicating it also has the characteristics of battery materials. α-MnO2 has a larger crystal tunnel structure, but its capacity is lower due to the smaller specific surface area and less structural oxygen vacancies. ε-MnO2 has a lower specific capacitance is not only the same disadvantage as α-MnO2, but also the disorder of its crystal structure. The tunnel size of β-MnO2 is not conducive to the interpenetration of electrolyte ions, but its high oxygen vacancy concentration makes its contribution of capacitance control obvious. EIS data shows that δ-MnO2 has the smallest charge transfer impedance and bulk diffusion impedance, while the two impedances of γ-MnO2 were the largest, which shows that its capacity performance has great potential for improvement. Combined with the calculation of electrode reaction kinetics and the performance test of five crystal capacitors and batteries, it is shown that δ-MnO2 is more suitable for capacitors and γ-MnO2 is more suitable for batteries.

… methods, battery “chemistry” resembles to day as before a black art. This is more true for manganese dioxide batteries than for … Modem manganese dioxide chemistry takes its beginning …

Aqueous rechargeable Zinc (Zn) batteries incorporating MnO2 cathodes possess favorable sustainability properties and are being considered for low‐cost, high‐safety energy storage. However, unstable electrode structures and unclear charge storage mechanisms limit their development. Here, advanced transmission electron microscopy, electrochemical analysis, and theoretical calculations are utilized to study the working mechanisms of a Zn/MnO2 battery with a Co2+‐stabilized, tunnel‐structured α‐MnO2 cathode (CoxMnO2). It is shown that Co2+ can be pre‐intercalated into α‐MnO2 and occupy the (2 × 2) tunnel structure, which improves the structural stability of MnO2, facilitates the proton diffusion and Zn2+ adsorption on the MnO2 surface upon battery cycling. It is further revealed that for the MnO2 cathode, the charge storage reaction proceeds mainly by proton intercalation with the formation of α‐HyCoxMnO2, and that the anode design (with or without Zn metal) affects the surface adsorption of by‐product Zn4SO4(OH)6·nH2O on MnO2 surface. This work advances the fundamental understanding of rechargeable Zn batteries and also sheds light on efficient electrode modifications toward performance enhancement.

… Batteries based on manganese dioxide (MnO 2 ) cathodes … Zn–MnO 2 cells, if cycled at reduced depth of discharge (DOD), have been found to achieve substantial cycle life with battery …

… more zinc manganese dioxide (Zn–Mn) batteries are … Zn–Mn batteries have been produced annually after 2002 in China. After their lifespan, the same amount of spent Zn–Mn batteries (…

… production and transport is most significant for PbA and MnO 2 /Zn batteries. This is … battery was found to be most sensitive to changes in battery service life and efficiency. For MnO 2 /Zn …

… for a number of different size Leclanché cells produced by various manufacturers. The … positive manganese dioxide electrode for all Leclanché cells assuming ideal behavior for each …

… the cell on test, and the potential variation across the cell … internal resistance of the Leclanché cells. The internal resistance … resistance of D‐size Leclanché cells, both undischarged and …

This paper deals with the equilibrium reactions in dry cells of the Leclanché type and the products formed as a result of discharge. X‐ray diffraction methods and the petrographic …

… There are several possible processes by which a voltaic cell might … cell reaction to the opposite electrode system is a theoretical possibility for any cell, the reactants of the Leclanch6 cell …

… investigation was to alternately charge and discharge the Leclanche cells (circuits 2, 3, and 4 … The comparison between cells so treated and other cells (circuit 1, Fig. 2) which were not …

… cells has been investigated using the impedance technique over an extensive frequency range. The frequency responses of Leclanché cells in … The component factors of the whole-cell …

A liquid-to-gel based Leclanché cell has been designed, constructed and characterized for use in implantable medical devices and other applications where battery access is limited. This well-established chemistry will provide reliable electrochemical potential over a wide range of applications and the novel construction provides a solution for the re-charging of electrodes in hard to access areas such as an internal pacemaker. The traditional Leclanché cell, comprised of zinc (anode) and manganese dioxide (cathode), conductive carbon powder (acetylene black or graphite), and aqueous electrolyte (NH4Cl and ZnCl2), has been suspended in an agar hydrogel to simplify construction while maintaining electrochemical performance. Agar hydrogel, saturated with electrolyte, serves as the cell support and separator allowing for the discharged battery suspension to be easily replaced once exhausted. Different amounts of active anode/cathode material have been tested and discharge characteristics have been plotted. It has been found that for the same amount of active material, acetylene black batteries have higher energy density compared to graphite batteries. Graphite batteries also discharge faster compared to acetylene black batteries. The results support further development of liquid batteries that can be replaced and refilled upon depletion.

The reduction products formed at various stages of discharge of gamma MnO 2 in solutions of NH 4 Cl, KCl, MnCl 2 , and AlCl 3 have been studied by means of thermogravimetry, …

… Data obtained on Leclanche cells using this technique are presented, … of cells, but met with only limited success. These authors further found the internal resistance of Leclanche cells to …

R20 sized Leclanché cells containing EMD and traditional or ZnCl 2 electrolyte have been discharged through 4 Ω for 15, 30 and 60 min/day. Measurement of recuperated zinc …

The cathodic reaction in the Leclanché dry cell has been described previously as consisting of two steps. The first of these steps is the electrochemical reduction Mn IV to Mn II . The …

… In summary, discharge of a traditional Leclanche cell occurs by a sequence of overall reactions which are shown as stages 0 and 1 in the Introduction and as stages 2 (modified), 3 (…

… It was pointed out by Kozawa(9) that polarization of Mn02 evaluated in KOH solution is useful to evaluate polarization of Mn02 in Leclanche cells. The cathode mix of dry cells is a …

… and chemical constituents of Leclanché cells. Using the same specified materials for preparing the cells, he has determined the output of these cells when operating under widely …

… cells show that these cells undergo greater instantaneous voltage fluctuation than the conventional Leclanch6 cells… for measuring internal resistances of dry cells described in this paper …

… CONCLUSIONS Despite the tremendous variability that is apparent in the Leclanche cells in this study, as evidenced by the GVs in Tables 7 and 8 and the capacity loss rates in Tables 9…

… I am glad to note that they have altered their opinion and I think Europe Storage of Leclanche Cells in Various Environments 245 will do the same, but I think we thought of it first. Now …

… their use in primary alkaline Zn batteries, and some niche secondary batteries, there is an … The alkaline Zn||MnO 2 system has seen great commercial success as a primary battery, …

… an alkaline … alkaline zinc–manganese dioxide (Zn–MnO 2 ) batteries made with powders in anode gels are assembled and tested. The electrochemical characteristics of the batteries …

… of rechargeable manganese dioxide−zinc (MnO 2 −Zn) batteries under both alkaline and … −Zn system from Leclanché cell to alkaline primary batteries and from primary to secondary …

… Alkaline Manganese Dioxide Zinc (RAM™) cells was not caused by the EMD cathode, but by the gelled zinc … mainly controlled the fade of RAM battery capacity, while rechargeability of …

… Zn–MnO 2 alkaline batteries have been the dominant primary … alkaline batteries is limited by the Zn anode mass, one possible pathway to enhance the energy density is to modify the Zn …

… of the rechargeable alkaline system to compete in secondary battery markets, based on … Since zinc is a high-power electrode, as is apparent from its use in silver-zinc batteries, the …

… We know that an alkaline battery comprises a zinc anode and a magnesium oxide cathode. … manganese dioxide for use in rechargeable alkaline zinc/manganese dioxide batteries. J. …

… The cathodic discharge/charge reactions involved in the present cell system proceed via a … In the discharge reaction, the MnO 2 powders loaded in the composite cathodes are …

… This study emphasizes the significance of in situ techniques to investigate the reaction mechanism of MnO 2 cathodes in aqueous batteries. The reversible Raman peak shift of the Mn–…

… 4) in the discharge of a manganese dioxide cathode constructed with powdered electrolytic … -generating mechanism of MnO2 presented in this paper, the potential of pure MnO2 has …

… mechanism of charge storage still remains ambiguous owing to the complexity of side reactions in aqueous electrolytes. This report explored the fundamental reaction mechanism of Zn/…

Abstract Rechargeable Zn/MnO2 battery chemistry in mildly acidic aqueous electrolytes has attracted extensive attention because of its properties as safe, inexpensiveness, and high theoretical specific capacity of cathode/zinc anode. However, the major limitation of MnO2 cathode is its unclear energy storage mechanism. Herein, the reaction mechanism in ZnSO4+MnSO4 electrolyte is investigated by various electrochemical and structural analysis based on two different structure manganese dioxide (α-MnO2 and δ-MnO2) and Zn4SO4(OH)6·4H2O (ZHS) prepared on purpose. We find that the Zn/MnO2 battery is dominated by the Dissolution-Deposition reaction mechanism, while the classical cations (H+, Zn2+) Intercalation/De-intercalation mechanism contributes little capacity in energy storage process. The major limitations of reaction kinetics, such as ZHS and active H2O, are explored in this work. We believe that the systematic research on the Dissolution/Deposition mechanism is useful for researchers to understand the energy storage mechanism of Zn/MnO2 battery.

Aqueous Zn/α-MnO2 batteries have attracted immense interest owing to their high energy density, low cost, and safety, making them desirable for future large-scale energy application. Despite these merits, the comprehensive understanding of their reaction mechanism has been elusive due to the limitations of standard bulk characterization. Here, via transmission electron microscopy, the dissolution-mediated reaction mechanism of a Zn/α-MnO2 system is discovered and explored in full scope to involve reversible formation of Zn4 SO4 (OH)6 ·xH2 O and "birnessite-like" Zn-MnOx phase upon cycling. Overall, α-MnO2 acts primarily as a source for cell activation through dissolution and thus is not directly involved in the Zn redox chemistry. This microscopic study offers a unique knowledge on the unconventional reaction chemistry of Zn/α-MnO2 batteries.

Abstract Manganese dioxide, MnO2, is one of the most promising electrode reactants in metal-ion batteries because of the high specific capacity and comparable voltage. The storage ability for various metal ions is thought to be modulated by the crystal structures of MnO2 and solvent metal ions. Hence, through combing the relationship of the performance (capacity and voltage) with the polymorphs of the MnO2 and metal ions in different solvents (organic and aqueous), three main energy storage mechanisms were found to be responsible for the different electrochemical processes. Furthermore, this review summarizes the main challenge and gives a direction for profound study in the future.

… the electrochemical activity of manganese dioxide at a battery set. Chemical manganese dioxide, CMD, and electrolytic manganese dioxide, EMD, which have been destroyed after …

… , which can improve the conductivity of the MnO 2 @N cathode. Also, there is Mn-N bond in … 2 @N cathode. In addition, the electrochemical mechanism of MnO 2 @N cathode has been …

Rechargeable aqueous Zn-MnO2 batteries are a promising candidate for large-scale energy storage systems thanks to their unparalleled features such as high safety, low cost, and environmental friendliness. Considering the controversies surrounding the mechanism of this battery containing a mildly acidic electrolyte, the electrochemical behavior of this type of battery using β-MnO2 as the cathode is systematically investigated. The results indicate that the reversible intercalation of Zn2+ ions into MnO2 is not likely to take place in the aqueous system. We conclude that it is the existence of water molecule and its participation in the electrochemical reactions, for instance, the reversible insertion of proton into MnO2 and the electrolysis of water that makes the mechanism of aqueous Zn-MnO2 batteries complicated. Besides, the capacity fading of this mildly acidic Zn-MnO2 battery is assigned to the generation of the inert layer of Zn4SO4(OH)6nH2O and the ZnMn2O4 on the cathode via electrochemical conversion reactions, the dissolution of the active material during discharging, and the release of gases. When Mn2+ ions are available in the electrolyte, they will be electrodeposited on the cathode during charging process and the kinetics of the electrochemical reactions of the electrode are improved, leading to the higher electrochemical performance of the battery.

Abstract Poor cycling stability and mechanistic controversies have hindered the wider application of rechargeable aqueous Zn–MnO2 batteries. Herein, direct evidence was provided of the importance of Mn2+ in this type of battery by using a bespoke cell. Without pre‐addition of Mn2+, the cell exhibited an abnormal discharge–charge profile, meaning it functioned as a primary battery. By adjusting the Mn2+ content in the electrolyte, the cell recovered its charging ability through electrodeposition of MnO2. Additionally, a dynamic pH variation was observed during the discharge–charge process, with a precipitation of Zn4(OH)6(SO4)⋅5H2O buffering the pH of the electrolyte. Contrary to the conventional Zn2+ intercalation mechanism, MnO2 was first converted into MnOOH, which reverted to MnO2 through disproportionation, resulting in the dissolution of Mn2+. The charging process occurred by the electrodeposition of MnO2, thus improving the reversibility through the availability of Mn2+ ions in the solution.

… For the discharge of MnO2 in alkaline electrolytes, the mechanism proposed by … -step mechanism for the reduction of 7-MnO2 in alkaline solution. The first step is reduction from MnO2 to …

… stable manganese dioxide samples via a dissolution-precipitation mechanism that involves disproportionation of a soluble Mn(III) intermediate. The resultant manganese dioxide …

… Most commercially produced primary alkaline Zn/MnO 2 batteries use γ-MnO 2 in the form of electrolytic manganese dioxide (EMD) as the active cathode material because of its …

Aqueous zinc-ion batteries (ZIBs) have attracted extensive attention in recent years because of its high volumetric energy density, the abundance of zinc resources, and safety. However, ZIBs still suffer from poor reversibility and sluggish kinetics derived from the unstable cathodic structure and the strong electrostatic interactions between bivalent Zn2+ and cathodes. Herein, magnesium doping into layered manganese dioxide (Mg-MnO2 ) via a simple hydrothermal method as cathode materials for ZIBs is proposed. The interconnected nanoflakes of Mg-MnO2 possess a larger specific surface area compared to pristine δ-MnO2 , providing more electroactive sites and boosting the capacity of batteries. The ion diffusion coefficients of Mg-MnO2 can be enhanced due to the improved electrical conductivity by doped cations and oxygen vacancies in MnO2 lattices. The assembled Zn//Mg-MnO2 battery delivers a high specific capacity of 370 mAh g-1 at a current density of 0.6 A g-1 . Furthermore, the reaction mechanism confirms that Zn2+ insertion occurred after a few cycles of activation reactions. Most important, the reversible redox reaction between Zn2+ and MnOOH is found after several charge-discharge processes, promoting capacity and stability. It believes that this systematic research enlightens the design of high-performance of ZIBs and facilitates the practical application of Zn//MnO2 batteries.

… to the Zn−PEO system enables solid battery performance to approach that of the liquid counterpart under low drain conditions. Flexible, conducting, and high surface area carbon …

… carbon rods, in the form of consistent, rather thick, highly porous, and low‐resistance layers. The battery … The performance of the battery has been studied, and it shows characteristics …

… for carbon conductive additives. Zinc-carbon batteries assembled using these carbon materials show advantages in electrode conductivity, specific capacity, rate performance, …

… -type zinc–carbon battery with high performance. The fiber battery comprises two carbon fiber based … The fiber battery does not exhibit any loss in the capacity during the bending tests, …

… The superior performance of raw … Performance data of different cells are listed in Table 2, which shows that increasing the concentration of CNTs enhanced battery performance. The …

Abstract The morphology of Zinc (Zn) deposits was investigated as anode for aqueous batteries. The Zn was deposited from zinc sulfate solution in direct current conditions on a copper surface at different current densities. The morphology characterization of Zn deposits was performed via field emission scanning electron microscopy. The Zn deposits transformed from a dense and compact structure to dendritic form with increasing current density. The electrodeposition of Zn with a current density of 0.02 A cm−2 exhibited good morphology with a high charge efficiency that reached up to 95.2%. The Zn deposits were applied as the anode in zinc–air and zinc–carbon batteries, which gave specific discharge capacities of 460 and 300 mA h g−1, respectively.

"Chemically modified" manganese oxide materials as Bi and Pb birnessites, prepared by ion exchange and coprecipitation methods, are shown to have no inherent limitations to their cycle life even under the condition of deep discharge reaching 80‐95% of their theoretical two‐electron capacity in each cycle.

… optimization of the manganese dioxide electrodeposition process. The electrochemical properties of electrodeposited MnO 2 on Au electrode have been investigated using rotating disc …

… 5 wt%) of Bi 2 O 3 in to chemically modified, physically modified manganese dioxide and also γ-manganese dioxide showing the importance of bismuth in the rechargeability of EMD. Fig…

In this study MnO 2 preparation by chemical methods is investigated for possible applications in dry cell batteries of chemical manganese dioxide (CMD) instead of electrolytic …