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Metal Oxides for Rechargeable Batteries Energy Applications

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Abstract

Nearly three decades of significant academic and commercialization progress, appreciations have to be credited for Li+ ion-based rechargeable secondary batteries, which conquered the entire world. The Li+ ion batteries dictate the consumer battery market and are considered crucial for the practical realization of plug-in hybrid electric vehicles (PHEVs), hybrid electric vehicles (HEVs), and electric vehicles (EVs). Recently, post-lithium–ion batteries, particularly Na, K, Mg, and Zn, and Al–ion batteries have also been intensively explored for various energy storage tenders due to their natural abundance, low cost, and environmental safety of these materials. The utilization of metal oxides in battery application is tremendous and, an example, the first commercial lithium ion batteries by Sony Co. with LiCoO2 as a cathode. Recently, Ni-rich layered oxide-based lithium ion batteries are on an edge of commercialization. The focus on battery research had increased drastically from 2010, and still metal oxide-based cathodes/anodes are researched exclusively due to their significant physicochemical properties. This chapter emphasizes electrochemical properties of various metal oxide-based electrode materials for various secondary rechargeable energy storage applications including sodium ion batteries (SIBs), potassium ion batteries (PIBs), and zinc ion batteries (ZIBs).

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Due to massively growing demand arising from energy storage systems, sodium ion batteries (SIBs) have been recognized as the most attractive alternative to the current commercialized lithium ion batteries (LIBs) owing to the wide availability and accessibility of sodium. Unfortunately, the low energy density, inferior power density and poor cycle life are still the main issues for SIBs in the current drive to push the entire technology forward to meet the benchmark requirements for commercialization. Over the past few years, tremendous efforts have been devoted to improving the performance of SIBs, in terms of higher energy density and longer cycling lifespans, by optimizing the electrode structure or the electrolyte composition. In particular, among the established anode systems, those materials, such as metals/alloys, phosphorus/phosphides, and metal oxides/sulfides/selenides, that typically deliver high theoretical sodium-storage capacities have received growing interest and achieved significant progress. Although some review articles on electrodes for SIBs have been published already, many new reports on these anode materials are constantly emerging, with more promising electrochemical performance achieved via novel structural design, surface modification, electrochemical performance testing techniques, etc. So, we herein summarize the most recent developments on these high-performance anode materials for SIBs in this review. Furthermore, the different reaction mechanisms, the challenges associated with these materials, and effective approaches to enhance performance are discussed. The prospects for future high-energy anodes in SIBs are also discussed.
Article
Due to the abundance of sodium sources and relatively high safety, sodium-ion batteries (SIBs) are considered as a promising candidate for next-generation large-scale energy storage systems. However, currently the lack of suitable anode materials is limiting the development of SIBs. Metal oxides (MOs) which have the advantage of rich material sources and high theoretical capacity have attracted lots of attention as anode for SIBs in scientific community. Nevertheless, due to the low conductivity, large volumetric change during charge/discharge process of SIBs, the material often demonstrates unsatisfactory cycling stability and capacity rate. Construction of material composites through incorporation of graphene to MOs with tailored nanostructure and composition has demonstrated promising performance in SIBs. In this review, we attempt to provide a comprehensive summary of the research development on the low-cost metal oxides/graphene composites (MOs/G) as anode materials for SIBs. The characteristics of different morphology, composition, crystal phases of MOs/G composites and their electrochemical properties in SIBs are demonstrated. The correlation of the morphological and structural properties of the MOs materials with their performance in SIBs is discussed. This timely review sheds light on the path towards achieving cost effective, safe SIBs with high energy density and long cycling life using MOs/G as anode materials.
Article
Stoichiometric LiMnO2 and NaMnO2 with a cation-disordered rocksalt-type structure as metastable polymorphs are successfully prepared by mechanical milling. Although cation-disordered rosksalt phases with a stoichiometric composition (Li:Mn molar ratio = 1:1), are expected to be electrochemically less active, both samples show superior performance as electrode materials when compared with thermodynamically stable layered phases in Li/Na cells. Both metastable samples deliver large reversible capacities, which correspond to >80% of theoretical capacities with relatively small polarization on the basis of reversible Mn3+/Mn4+ redox. Moreover, for rocksalt LiMnO2, phase transition into a spinel phase is effectively suppressed compared with a thermodynamically stable phase. Electrode reversibility of NaMnO2 is also drastically improved by the use of the metastable phase with good capacity retention. Metastable phases with unique nanostructures open a new path to design the advanced electrode materials with high energy density, and thus broad impact is anticipated for rechargeable Li/Na battery applications.
Article
Mesoporous orthorhombic LiMnO2 has been directly fabricated by a one-step flux method in this work. Benefiting from the unique mesoporous structure, the orthorhombic LiMnO2 prepared through calcinating the mixture of flux LiOH H2O and Mn2O3 with various Li/Mn molar ratios shows enhanced lithium storage properties. When used as the cathode for lithium ion battery, the mesoporous orthorhombic LiMnO2 has been found to exhibit a maximum discharge capacity of 191.5 mAh g⁻¹ and a high reversible capacity of 162.6 mAh g⁻¹ (84.9% retention) after 50 cycles at a current density of 0.1 C rate. These results demonstrate its potential application in high performance lithium-ion batteries.
Article
The electrochemical storage of sodium ions from aqueous electrolytes in transition metal oxides is of interest for energy and sustainability applications. These include low-cost and safe energy storage and energy-efficient water desalination. The strong interactions between water and transition metal oxide surfaces, as well as those between water and sodium ions, dictate the stability and electrochemical energy storage mechanisms in these materials. This review summarizes the implications of water as an electrolyte solvent for transition metal oxide electrodes, and sodium ion intercalation from neutral pH electrolytes into a diverse set of transition metal oxides. Increased control of the aqueous electrolyte/transition metal oxide interface is likely to lead to improvements in stability and capacity, which are critical breakthroughs for the implementation of transition metal oxides in aqueous sodium ion energy storage technologies.
Article
Transformational changes in battery technologies are critically needed to enable the effective use of renewable energy sources, such as solar and wind, and to allow for the expansion of the electrification of vehicles. Developing high-performance batteries is critical to meet these requirements, which certainly relies on material breakthroughs. This review article presents the recent progresses and challenges in discovery of high-performance anode materials for Li-ion batteries related to their applications in future electrical vehicles and grid energy storage. The advantages and disadvantages of a series of anode materials are highlighted.
Article
Sodium ion batteries (NIBs) are one of the versatile technologies for low-cost rechargeable batteries. O3-type layered sodium transition metal oxides (NaMO2, M = transition metal ions) are one of the most promising positive electrode materials considering their capacity. However, the use of O3 phases is limited due to their low redox voltage and associated multiple phase transitions which are detrimental for long cycling. Herein, a simple strategy is proposed to successfully combat these issues. It consists of the introduction of a larger, nontransition metal ion Sn⁴⁺ in NaMO2 to prepare a series of NaNi0.5Mn0.5− ySn yO2 (y = 0–0.5) compositions with attractive electrochemical performances, namely for y = 0.5, which shows a single-phase transition from O3 ⇔ P3 at the very end of the oxidation process. Na-ion NaNi0.5Sn0.5O2/C coin cells are shown to deliver an average cell voltage of 3.1 V with an excellent capacity retention as compared to an average stepwise voltage of ≈2.8 V and limited capacity retention for the pure NaNi0.5Mn0.5O2 phase. This study potentially shows the way to manipulate the O3 NaMO2 for facilitating their practical use in NIBs.
Article
Transition metal vanadates have attracted much attention for high capacity anodes of lithium ion batteries (LIBs). However, they have obvious drawbacks (short cycle-lives and low rate performance) because of the intrinsically low electronic conductivity and serious volume variation during Li-ion desorption and insertion. In particular, pure Co3V2O8 micro-pencils (pCVO MPs) have a stable and regular crystal structure, large tap density and uniform grain size, but, unfortunately, they have not exhibited expected electrochemical performance. Herein, we report the successful preparation of reduced graphene oxide coated Co3V2O8 micro-pencils (rGO@CVO MPs) through a facile approach combining hydrothermal synthesis with thermal reduction. When tested as anodes for LIBs, rGO@CVO MPs exhibit superior electrochemical performance compared to that of pure Co3V2O8 micro-pencils (pCVO MPs). The anodes of rGO@CVO MPs show a high reversible capacity of 760 mA h g⁻¹ over 200 cycles at 200 mA g⁻¹, and 500 mA h g⁻¹ can remain after 500 cycles at 1000 mA g⁻¹, with an increase in 200 mA h g⁻¹ in contrast to the pCVO MPs. It is consequently demonstrated that the composite material (rGO@CVO MPs) is a promising anode material for LIBs.
Article
A novel layered ternary material K0.67Ni0.17Co0.17Mn0.66O2 has been fabricated via a co-precipitation assisted solid-phase method and further evaluated as a cathode for potassium-ion batteries for the first time. Highly reversible K⁺ intercalation/deintercalation is demonstrated in this material. It delivers a reversible capacity of 76.5 mAh/g with average voltage of 3.1 V and shows good cycling performance with capacity retention of 87% after 100 cycles at 20 mA/g. This work may give a new insight into developing cathode materials for potassium-ion batteries.
Article
Novel and low-cost batteries are of considerable interest for application in large-scale energy storage systems, for which the cost per cycle becomes critical. Here, this study proposes K0.5MnO2 as a potential cathode material for K-ion batteries as an alternative to Li technology. K0.5MnO2 has a P3-type layered structure and delivers a reversible specific capacity of ≈100 mAh g−1 with good capacity retention. In situ X-ray diffraction analysis reveals that the material undergoes a reversible phase transition upon K extraction and insertion. In addition, first-principles calculations indicate that this phase transition is driven by the relative phase stability of different oxygen stackings with respect to the K content.
Article
Zn3V2O8 (ZVO) with sheet-like morphology is synthesized by a simple green precipitation technique via a metal-organic framework (MOF) intermediate for use as an anode in high energy lithium-ion batteries (LIBs). This sheet-like morphology, enriched with highly porous features, is evident from transmission electron microscopy (TEM) and surface area measurements. When tested as a lithium half-cell electrode, the ZVO porous sheets delivered a reversible specific capacity of 1228 mA h g⁻¹ at a current density of 0.3 A g⁻¹ for 200 cycles. Interestingly, on applying two different high current densities of 1 and 3 A g⁻¹, this porous ZVO material registered high capacities of 665 and 510 mA h g⁻¹, initially for 30 and 50 cycles, respectively. On reducing the current density to 0.5 and 1 A g⁻¹ for the two instances, both sustained stable capacities of 906 and 687 mA h g⁻¹ in the 160th and 600th cycles, respectively. The fact that these porous sheets maintained a stable capacity as high as 370 mA h g⁻¹ at the high applied current density of 5 A g⁻¹ after 2000 discharge/charge cycles reveals the structural stability of the ZVO prepared by a simple green precipitation technique.
Article
We report a study of the structural evolution of P2-Na0.67[Mn0.66Fe0.20Cu0.14]O2 positive electrode for Na-ion batteries during (NIBs) charge and discharge. Operando X-ray diffraction (XRD) analysis revealed two phase transitions over the first cycle (1.5 - 4.3 V). Ex-situ pair distribution function (PDF) analysis was used to characterize the local structure of the high voltage phase observed in many Fe-containing layered P2-struture oxide materials. The high voltage phase is disordered along the c-axis and is derived by the migration of a fraction of iron ions into the interlayer space. Operando X-ray absorption spectroscopy (XAS) was employed to monitor the local structure evolution of the transition metals, showing the existence of Mn3+/4+ redox below ~ 3.4 V, followed by the redox activity of Cu and Fe ions at higher voltages. No evident change was observed in the K-edge X-ray absorption near edge structure (XANES) of the transition metals at voltages above 4.1 V, where the growth of the high voltage phase is initiated. These results imply the reversible contribution of oxide ions in the redox process. This process results in voltage fading over cycling, similar to Li2MnO3-based positive electrode materials in Li-ion batteries.
Article
Transition metal oxides (TMOs), based on conversion reaction, are attractive candidate anode materials for lithium-ion batteries (LIBs) because of their high theoretical capacity and safety characteristics. In this review, we will summarize recent progress on the rational design and efficient synthesis of TMOs with controlled morphologies, composition, and micro-/nanostructures, along with their Li storage behaviors. Single metal oxides of manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), ruthenium (Ru), chromium (Cr), molybdenum (Mo), and tungsten (W), and their common binary metal oxides are covered in this review. Finally, the ignored merits of conversion reaction is put forward, and the design of metal oxides electrode by making full use of the merits is proposed.
Article
P2-type layered Na2/3Ni1/4Mn3/4O2 has been synthesized by a solid-state method and its electrochemical behavior has been investigated as a potential cathode material in aqueous hybrid sodium/lithium ion electrolyte by adopting activated carbon as the counter electrode. The results indicate that the Na⁺/Li⁺ ratio in aqueous electrolyte has a strong influence on the capacity and cyclic stability of the Na2/3Ni1/4Mn3/4O2 electrode. Increase on the Li⁺ content leads to a shift of the redox potential towards a high value, which is favorable for the improvement of the working voltage of the layered material as cathode. It is found that the coexistence of Na⁺ and Li⁺ in aqueous electrolyte can improve the cyclic stability for the Na2/3Ni1/4Mn3/4O2 electrode. A reversible capacity of 54 mAh g⁻¹ was obtained with a high cyclability as the Na⁺/Li⁺ ratio was 2:2. Furthermore, an aqueous hybrid ion cell was assembled with the as-proposed Na2/3Ni1/4Mn3/4O2 as cathode and NaTi2(PO4)3/graphite synthesized in this work as anode in 1 M Na2SO4/Li2SO4 (mole ratio as 2:2) mixed electrolyte. The cell shows an average discharge voltage at 1.2 V, delivering an energy density of 36 Wh kg⁻¹ at a power density of 16 W kg⁻¹ based on the total mass of the active materials.
Article
A spherical stoichiometric LiNiO2 particle, which was composed of compactly packed nanosized primary particles, was prepared and cycled at different cutoff voltages to explicitly demonstrate the effect of phase transitions during Li deintercalation/intercalation on the Li-ion intercalation stability of LiNiO2. The capacity retention was greatly improved by suppressing the H2 → H3 phase transition at 4.1 V, such that 95% of the initial capacity (164 mAh g–1) was retained after 100 cycles when cycled at 4.1 V. At 4.2 and 4.3 V, continuous capacity loss (81% of 191 mAh g–1 at 4.2 V and 75% of 232 mAh g–1 at 4.3 V after 100 cycles) was observed during cycling, and these electrodes incurred extensive structural damages (micro-, hairline and nanoscale cracks observed by transmission electron microscopy) from the repeated lattice contraction and expansion accompanying the H2 → H3 transition, in agreement with the cycling data.
Article
Layered metal oxides have attracted increasing attention as cathode materials for sodium-ion batteries (SIBs). However, the application of such cathode materials is still hindered by their poor rate capability and cycling stability. Here, a facile self-templated strategy is developed to synthesize uniform P2-Na0.7 CoO2 microspheres. Due to the unique microsphere structure, the contact area of the active material with electrolyte is minimized. As expected, the P2-Na0.7 CoO2 microspheres exhibit enhanced electrochemical performance for sodium storage in terms of high reversible capacity (125 mAh g(-1) at 5 mA g(-1) ), superior rate capability and long cycle life (86 % capacity retention over 300 cycles). Importantly, the synthesis method can be easily extended to synthesize other layered metal oxide (P2-Na0.7 MnO2 and O3-NaFeO2 ) microspheres.
Article
Large-scale electric energy storage is fundamental to the use of renewable energy. Recently, research and development efforts on room-temperature sodium-ion batteries (NIBs) have been revitalized, as NIBs are considered promising, low-cost alternatives to the current Li-ion battery technology for large-scale applications. Herein, we introduce a novel layered oxide cathode material, Na0.78Ni0.23Mn0.69O2. This new compound provides a high reversible capacity of 138 mAh g-1 and an average potential of 3.25 V vs. Na+/Na with a single smooth voltage profile. Its remarkable rate and cycling performances are attributed to the elimination of the P2-O2 phase transition upon cycling to 4.5 V. The first charge process yields an abnormally excess capacity which has yet to be observed in other P2 layered oxides. Metal K-edge XANES results show that the major charge compensation at the metal site during Na-ion deintercalation is achieved via the oxidation of nickel (Ni2+) ions, whereas, to a large extent, manganese (Mn) ions remain in their Mn4+ state. Interestingly, Electron Energy Loss Spectroscopy (EELS) and soft X-ray Absorption Spectroscopy (sXAS) results reveal differences in electronic structures in the bulk and at the surface of electrochemically-cycled particles. At the surface, transition metal ions (TM ions) are in a lower valence state than in the bulk, and the O K-edge pre-peak disappears. Based on previous reports on related Li-excess LIB cathodes, it is proposed that part of the charge compensation mechanism during the first cycle takes place at the lattice oxygen site, resulting in a surface to bulk transition metal gradient. We believe that by optimizing and controlling oxygen activity, Na layered oxide materials with higher capacities can be designed.
Article
K-ion battery (KIB) is a new-type energy storage device which possesses potential advantages of low-cost and abundant resource of K precursor materials. However, the main challenge lies on the lack of stable materials to accommodate the intercalation of large-size K-ions. Here we designed and constructed a novel earth abundant Fe/Mn-based layered oxide interconnected nanowires as a cathode in KIBs for the first time, which exhibits both high capacity and good cycling stability. On the basis of advanced in situ X-ray diffraction (XRD) analysis and electrochemical characterization, we confirm that interconnected K0.7Fe0.5Mn0.5O2 nanowires can provide stable framework structure, fast K-ion diffusion channels and three-dimensional electron transport network during the depotassiation/potassiation processes. As a result, a considerable initial discharge capacity of 178 mAh g-1 is achieved when measured for KIBs. Besides, K-ion full batteries based on interconnected K0.7Fe0.5Mn0.5O2 nanowires/soft carbon are assembled, manifesting over 250 cycles with a capacity retention of ~76%. This work may open up the investigation of high-performance K-ion intercalated earth abundant layered cathodes and will push the development of energy storage systems.