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Unstable Zn interface with serious detrimental parasitic side‐reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc‐ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn‐ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn‐ions and guide the Zn‐ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc‐ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc‐ion distribution by using its positively charged −NR4+ groups. While the negatively charged −SO3− groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn‐ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side‐reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm−2, 0.25 mAh cm−2). Additionally, based on this strategy, the NH4V4O10||Zn pouch‐cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch‐cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles. [ABSTRACT FROM AUTHOR]

With the large-scale application of lithium-ion batteries, the recycling of retired LIBs has been a crucial problem to address. Among the spent LIBs, LiFePO4 (LFP) recycling is urgently needed as it is one of the most extensively utilized cathodes in the sustainable development of LIBs. However, traditional pyro-/hydro-metallurgical recycling methods are normally complicated and uneconomical. Here, we exhibit an efficient and green method with a simple route to regenerate a degraded LiFePO4 cathode, through which the cathode sheets are directly broken down into aluminum foil, high-purity FePO4 and lithium-containing solution by the introduction of hydrogen peroxide as a leaching reagent. The leaching efficiency of Li exceeds 96.3% with scarce Al and Fe, and the regenerated LiFePO4 from recovered FePO4 displays excellent rate capability and long-term cycling stability. This research greatly reduces the processing steps and chemical consumption, which is conducive to the sustainable industrial development of spent lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The ever‐increasing energy density requirements in electric vehicles (EVs) have boosted the development of Ni‐rich layered oxide cathodes for state‐of‐the‐art lithium‐ion batteries. Nevertheless, the commercialization of polycrystalline Ni‐rich cathodes (PCNCs) is hindered by the severe performance degradation and safety concerns that are tightly related to its particle cracking during cycling. Single‐crystalline Ni‐rich cathodes (SCNCs) with eliminated grain boundaries and high mechanical strength have recently attracted extensive attention owing to their superior structural and cycling stability, which present high crack resistance during electrochemical operation. Various articles have focused on the trial‐and‐error synthesis and modifications of SCNCs, as well as the comparison of performances and mechanisms with PCNCs. However, there has been much less effort in systematic analysis and summary to reveal their key challenges, controversies, and the corresponding primary causes. In this review, the advantages and debates in structural and electrochemical properties of SCNCs over PCNCs are summarized to provide fundamental understanding of SCNCs. Then the current practical issues and challenges are comprehensively discussed from the viewpoints of both academia and industry, as well as the proposed modification strategies and underlying mechanisms for SCNCs. The outlook and perspectives are further given to facilitate the commercial applications of SCNCs in high‐performance EVs. [ABSTRACT FROM AUTHOR]

Highlights: The chemical process of local oxidation–partial reduction–deep coupling for stibnite reduction of carbon dots (CDs) is revealed by in-situ high-temperature X-ray diffraction. Sb2S3@xCDs anode delivers high initial coulombic efficiency in lithium ion batteries (85.2%) and sodium ion batteries (82.9%), respectively. C–S bond influenced by oxygen-rich carbon matrix can restrain the conversion of sulfur to sulfite, well confirmed by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations. CDs-induced Sb–O–C bond is proved to effectively regulate the interfacial electronic structure. The application of Sb2S3 with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency (ICE). In this work, natural stibnite modified by carbon dots (Sb2S3@xCDs) is elaborately designed with high ICE. Greatly, chemical processes of local oxidation–partial reduction–deep coupling for stibnite reduction of CDs are clearly demonstrated, confirmed with in situ high-temperature X-ray diffraction. More impressively, the ICE for lithium-ion batteries (LIBs) is enhanced to 85%, through the effect of oxygen-rich carbon matrix on C–S bonds which inhibit the conversion of sulfur to sulfite, well supported by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations. Not than less, it is found that Sb–O–C bonds existed in the interface effectively promote the electronic conductivity and expedite ion transmission by reducing the bandgap and restraining the slip of the dislocation. As a result, the optimal sample delivers a tremendous reversible capacity of 660 mAh g−1 in LIBs at a high current rate of 5 A g−1. This work provides a new methodology for enhancing the electrochemical energy storage performance of metal sulfides, especially for improving the ICE. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) are considered as excellent structural regulator for metal oxides (MOs) due to their abundant functional groups, superior dispersibility, and ultrasmall size (<10 nm). Herein, a new approach is proposed to construct porous pomegranate‐like MOs/CDs composite based on the CDs‐induced in situ growth mechanism of ion adsorption–multipoint surface nucleation–crosslinking agglomeration. The proposed methodology is successfully applied to prepare SnO2/CDs, Cu2O/CDs, and Fe2O3/CDs composites, respectively, demonstrating its universality to metal oxides. Taking SnO2/CDs composite as a case study for anode material in lithium‐ion batteries, it exhibits high lithium storage capacity, excellent cycling stability, and a special feature of capacity increase upon cycling. This study provides a new idea for the design of metal oxides materials tuned by CDs and broadens the application of CDs in the field of material synthesis. [ABSTRACT FROM AUTHOR]

The recycling of spent lithium-ion batteries (LIBs) is a crucial issue that has engaged extensive attention worldwide, along with the rapidly increasing usage of lithium-ion batteries. State-of-art recycling approaches, in terms of chemical leaching, have imperfections such as excessive chemical consumption, tedious recycling procedure and aggravated secondary pollution. In this research, a green and closed-loop route for the recycling of spent LiFePO4 involving oxidation leaching is demonstrated. By properly adjusting or controlling the leaching parameters, the leaching efficiency of lithium is up to 97.6% with the introduction of hydrogen peroxide, which is facilitated to achieve the transformed high-purity lithium carbonate and iron phosphate. The oxidation reaction mechanisms are clarified through thermodynamic and kinetic analyses, which identified that the oxidation leaching reaction is co-controlled by the internal diffusion and chemical reaction. Consequently, LiFePO4 cathode materials are regenerated by utilizing the obtained raw materials, as expected, which deliver superior cycling stability with less than 1% of capacity loss after 300 cycles and excellent rate performances. This research embodies the possibility of efficient recycling of LiFePO4 from spent lithium-ion batteries based on the principles of green chemistry that is possibly committed to the sustainability of the lithium-ion battery industry. [ABSTRACT FROM AUTHOR]

Silicene, as a two‐dimensional (2D) nanostructure of silicon with many active sites for charge distribution, suitable space to control the volumetric strain, and an adjustable bandgap has attracted more attention as an anode for lithium‐ion batteries. Nitrogen, with a small radius and high electronegativity, is pretty good to form an n‐type configuration of silicene. Herein, single‐crystal silicene with adjusting nitrogen atoms at pyrrolic and graphitic sites in the graphene layer is identified by XRD, XPS, and Raman analyses for nitrogen‐doped graphene/silicene (NG/SNS) composite. Electrochemical performance of silicene exhibits the first intercalation/deintercalation capacity of 1030/768 mAh/g with 74 % Columbic efficiency (CE) at a current density of 10 mA/g, whereas NG3‐SNS with 0.3 g NG precursor shows the first intercalation/deintercalation capacity of 795/600 mAh/g with 75.4 % CE. Interestingly, NG3‐SNS indicates a stable specific capacity of ∼600 mAh/g at 200th cycle with 100 % CE and a second volumetric capacity of 3352 mAh/cm3 with 80 % retention after 200 cycles at a current density of 100 mA/g. Subsequently, the high electronegativity of nitrogen results in lone pair in both hybridized configurations of graphitic‐NG and pyrrolic‐NG; which may cause effortless adsorption/desorption of Li+‐ion at the nitrogen sites, as well as, pyrrolic sites help to develop diffusion of Li+‐ion and graphitic sites help to accelerate the kinetics and surface‐controlled contributions. [ABSTRACT FROM AUTHOR]

As a high-capacity cathode material with a considerable cycle life, lithium metal orthosilicates have attracted much attention. In this paper, Li2FeSiO4, Li2FeSiO4−xClx and Li2FeSiO4−xFx are successfully synthesized via solid-state method. Li2FeSiO4−xFx is also composited with reduced graphene oxide (rGO). The X-ray diffraction patterns show 0.2% expansion in the lattice volume of Li2FeSiO4−xFx and 0.7% shrinkage for Li2FeSiO4−xClx due to the doping effect. Fourier-transform infrared spectroscopy also indicates a frequency shift for [SiO4]4− and [LiO4] functional groups due to ion doping. The SEM images confirm that rGO surrounded Li2FeSiO4−xFx microparticles. The electrochemical performance illustrates a reversible ox/red reaction of Fe2+/Fe3+ couple at the potential of 3/2.6 V for Li2FeSiO4, 3.5/2.9 V for Li2FeSiO4−xFx, and 3.3/2.3 V for Li2FeSiO4−xClx. Lithiation curves at 0.05C rate show the first specific capacity of 168 mAh g−1 for Li2FeSiO4 with 84% retention after 25th cycles, 190 mAh g−1 for Li2FeSiO4−xFx with 100% retention, and 120 mAh g−1 for Li2FeSiO4−xClx with 73% retention. Li2FeSiO4−xFx/rGO cathode delivers 265 mAh g−1 with 88% retention after 25th cycles. [ABSTRACT FROM AUTHOR]

Given the inherent features of open tunnel‐like pyrochlore crystal frameworks and pentavalent antimony species, polyantimonic acid (PAA) is an appealing conversion/alloying‐type anode material with fast solid‐phase ionic diffusion and multielectron reactions for lithium‐ion batteries. Yet, enhancing the electronic conductivity and structural stability are two key issues in exploiting high‐rate and long‐life PAA‐based electrodes. Herein, these challenges are addressed by engineering a novel multidimensional integrated architecture, which consists of 0D Mn‐substituted PAA nanocrystals embedded in 1D tubular graphene scrolls that are co‐assembled with 2D N‐doped graphene sheets. The integrated advantages of each subunit synergistically establish a robust and conductive 3D electrode framework with omnidirectional electron/ion transport network. Computational simulations combined with experiments reveal that the partial‐substitution of H3O+ by Mn2+ into the tunnel sites of PAA can regulate its electronic structure to narrow the bandgap with increased intrinsic electronic conductivity and reduce the Li+ diffusion barrier. All above merits enable improved reaction kinetics, adaptive volume expansion, and relieved dissolution of active Mn2+/Sb5+ species in the electrode materials, thus exhibiting ultrahigh rate capacity (238 mAh g−1 at 30.0 A g−1), superfast‐charging capability (fully charged with 56% initial capacity for ≈17 s at 80.0 A g−1) and durable cycling performance (over 1000 cycles). [ABSTRACT FROM AUTHOR]

Fabrication of Bi/C composites is a common approach to alleviate the severe volume expansion of Bi alloy‐based anodes with a high theoretical capacity of 3800 mAh cm−3 for lithium ion batteries (LIBs). However, the complicated and tedious synthetic routes restrict its large‐scale preparation and practical applications. Herein, a spongiform porous Bi/C composite (marked as Bi@PC) through the carbothermal reduction (CTR) method is constructed. Bi nanodots are in situ confined in a porous carbon substrate activated by the gases produced from the decomposition of the sodium phytate precursor, indicating the feasibility and simplicity of this route. In charge/discharge processes, Bi nanodots embedded in carbon matrix are effective enough to accommodate the strain change and shorten the migration distance. In addition, the porous carbon forms an efficient conductive network for electron shutting. When utilized for lithium storage, a superb capacity of 520 mAh g−1 at 0.2 A g−1 after 100 cycles and a satisfying long cyclic stability of 380 mAh g−1 at 0.5 A g−1 after 500 cycles are achieved. The excellent Li‐storage performance and this handy preparation method jointly make this Bi/C composite a potential anode for LIBs, and could inspire the preparation of other alloy‐type anodes. [ABSTRACT FROM AUTHOR]

High‐working potential layered oxides as cathode materials have been considered as an effective way to improve the energy density of Na‐ion batteries (NIBs) to enhance their competitiveness as a promising alternative for lithium ion batteries in large‐scale energy storage applications. However, they generally suffer irreversible phase transition, large volume change and electrolyte corrosion when charged to high voltage (>4.2 V), resulting in poor cyclic stability. In this work, a P2@tunnel heterostructure cathode material is designed and obtained by wet chemistry combined with solid‐state reaction method. Moreover, partly of the Ti4+ ions which are designed for the tunnel structure is also doped into the P2 phase under high temperature annealing process, resulting in expanded crystal parameters and smooth charge‐discharge profiles. The stable tunnel structure layer can effectively protect the layered P2 type cathode material from corrosion by electrolyte upon high voltage and alleviate the crack propagated from the particle surface. Therefore, the P2@tunnel heterostructure cathode can still maintain a discharge capacity of 146.3 mAh g−1 while the discharge capacity of pristine P2 type cathode is only 114.4 mAh g−1 after 100 cycles at 0.25 C, it also reveals superior cyclic stability and rate performance compared to the pristine P2 type cathode. [ABSTRACT FROM AUTHOR]

Advanced materials with various micro‐/nanostructures have attracted plenty of attention in energy storage field over the past decades. Metallic reduction reactions (MRRs) possess the merits of low energy consumption, flexibility, convenience, and scalability, which have been considered as potential methods to acquire diverse micro‐/nanostructured materials. In this review, the latest progress of MRRs is systematically summed up, featuring the usage of metallic reductants (e.g., magnesium, aluminum, zinc, lithium) on synthesizing of advanced micro‐/nanostructured materials and their applications in various energy storage systems. The as‐obtained materials (e.g., carbon‐, silicon‐, germanium‐, antimony‐, and titanium‐based materials) can deliver various architectures, including solid spherical structures, hollow porous structures, core–shell structures, yolk–shell structures, core–satellite structures, and many kinds of 1D, 2D, 3D micro‐/nanostructures. Besides, the defect properties of materials can be well tuned via MRRs. The application progress of these materials as active electrodes, host materials, or functional interlayers for lithium ion batteries, lithium sulfur batteries, sodium ion batteries, or supercapacitors is reviewed. In the end, the strengths and insufficiencies of MRRs are discussed and the probable future research directions of MRRs are proposed. [ABSTRACT FROM AUTHOR]

Demand for energy in day to day life is increasing exponentially. However, existing energy storage technologies like lithium ion batteries cannot stand alone to fulfill future needs. In this regard, potassium ion batteries (KIBs) that utilize K ions in their charge storage mechanism have attracted considerable attention due to their unique properties and are therefore established as one of the future battery systems of interest among the scientific community. Nevertheless, the development and identification of appropriate electrode materials is very essential for practical applications. This review features the current development in KIBs electrode and electrolyte materials, the present challenges facing this technology (in the commercial aspect), and future aspects to develop fully functional KIBs. The potassium storage mechanisms, evolution of the KIBs, and the advantages and disadvantages of each category of materials are included. Additionally, various approaches to enhance the electrochemical performances of KIBs are also discussed. This review is not only an amalgamation of different viewpoints in literature, but also contains concise perspectives and strategies. Moreover, the potential emergence of a novel class of K‐based dual ion batteries is also analyzed for the first time. [ABSTRACT FROM AUTHOR]

Considering serious pollution from the traditional chemical synthesis process, the resource-rich, clean electrode materials are greatly desired. Conventional electrochemical performance improvement methods, such as quantum dot or coating, are complicated and costly. In this study, CuFeS2 with an enhanced cycle performance is prepared from natural ore chalcopyrite through simple flotation and acid leaching. We obtain micro-sized CuFeS2 with high yield and purity. Electrochemical measurement shows that the natural chalcopyrite with an EDD-S electrolyte displays a high initial charge capacity (992 mAh·g−1 at the initial discharge current density of 0.2 C), an excellent rate performance, and good cycle property. The discharge capacities are approximately 870, 850, 830, 800, 750, and 680 mAh·g−1 at current densities of 0.1, 0.2, 0.3, 0.5, 1, and 2 C, respectively. When the current density is reduced back to 0.1 C, the reversible capacity can recover to 860 mAh·g−1, the cyclability is impressive (initial capacity of 700 mAh·g−1 and 660 mAh·g−1 maintained for 1000 cycles at a high current density of 2 C, corresponding to an excellent capacity retention of 94% after 1000 cycles). [ABSTRACT FROM AUTHOR]

Herein, we report the fabrication and application of Li‐ion anodes for utilisation within Li‐ion batteries, which are fabricated via additive manufacturing/3D printing (fused deposition modelling) using a bespoke graphene/polylactic acid (PLA) filament, where the graphene content can be readily tailored and controlled over the range 1–40 wt. %. We demonstrate that a graphene content of 20 wt. % exhibits sufficient conductivity and critically, effective 3D printability for the rapid manufacturing of 3D printed freestanding anodes (3DAs); simplifying the components of the Li‐ion battery negating the need for a copper current collector. The 3DAs are physicochemically and electrochemically characterised and possess sufficient conductivity for electrochemical studies. Critically, it is found that if the 3DAs are used in Li‐ion batteries the specific capacity is very poor but can be significantly improved through the use of a chemical pre‐treatment. Such treatment induces an increased porosity, which results in a 200‐fold increase (after anode stabilisation) of the specific capacity (ca. 500 mAh g−1 at a current density of 40 mA g−1). This work significantly enhances the field of additive manufacturing/3D printed graphene based energy storage devices demonstrating that useful 3D printable batteries can be realised. [ABSTRACT FROM AUTHOR]

Attributed to the high theoretical capacity and abundant reserve, Cu3Mo2O9 has been considered as a potential anode material for lithium‐ion batteries. Nevertheless, the severe capacity fading caused by structure collapse and particle aggregation seriously hinders its practical application. In this work, Cu3Mo2O9 coated with homogeneous polyaniline layer is obtained through oxidative polymerization of aniline on the surface of Cu3Mo2O9. The lithium storage performance is investigated systematically. As a result, a high reversible specific capacity of 800.2 mA h g−1 at a current density of 100 mA g−1 is delivered in Cu3Mo2O9@PANI anode even after 200 cycles, which is much higher than that of pristine Cu3Mo2O9 anode (373.8 mA h g−1). Furthermore, a high capacity of 675 mA h g−1 at a high current density of 1 A g−1 is achieved even after 700 cycles. This result evidences that the introduction of a polyaniline protective layer is an effective way to improve the structural stability of the Cu3Mo2O9 anode and further enhance cycling durability. This strategy is a starting point for the preparation and stabilization of other binary metal oxide composite materials for applications in lithium‐ion batteries. Icing on the cake: Cu3Mo2O9@PANI composites are designed as anode material for lithium‐ion batteries (LIB). The prepared electrode exhibits excellent lithium storage performance. An especially good cyclic stability is found, with a delivered stable reversible capacity of 675 mA h g−1 even after 700 cycles at a high current density of 1 A g−1. [ABSTRACT FROM AUTHOR]

Recently, the carbonization of metal organic frameworks (MOFs) has become an efficient method to prepare metal‐oxide materials on carbon support, which can provide advantages toward conversion‐type reactions of lithium ion batteries as the size and shape of the materials can be tuned by adjusting the MOF ligands. Formic acid is widely used in MOFs with diverse coordination models, which can further regulate morphologies of the carbonized metal oxides. However, less work is reported on the fabrication of metal oxides with formic acid ligands and their application as electrode materials. Herein, utilizing the self‐assembled MOFs [NH2(CH3)2][FeIIIFeII(HCOO)6] with formic acid ligands as the precursor, a carbon decorated Fe3O4 is successfully prepared, consisting of Fe3O4 nanoparticles with diameters of 40–60 nm and the coated carbon that is stemmed from the organic precursor of formic acid. When used as the electrode materials for lithium‐ion batteries, this composite exhibits good rate capability and stabilized reversible capacity of 1041 mAh g−1 after 50 cycles at 100 mA g−1. These superior properties can be attributed to the synergetic effect of the unique nano/micro structure and uniform dispersion of the conductive carbon provided by this new MOF precursor. Enter the (carbon) matrix: carbon decorated Fe3O4 nanoparticles are successfully designed and synthesized using a MOF precursor. The composite material is applied as anodes in lithium‐ion batteries. The electrodes exhibited good rate capability and stable reversible capacity of 1041 mAh g−1 after 50 cycles at a current density of 100 mA g−1. [ABSTRACT FROM AUTHOR]

The ever-increasing demand of lithium-ion batteries (LIBs) caused by the rapid development of various electronics and electric vehicles will be hindered by the limited lithium resource. Thus sodium-ion batteries (SIBs) have been considered as a promising potential alternative for LIBs owing to the abundant sodium resource and similar electrochemical performances. In recent years, significant achievements regarding anode materials which restricted the development of SIBs in the past decades have been attained. Significantly, the sodium storage feasibility of carbon materials with abundant resource, low cost, nontoxicity and high safety has been confirmed, and extensive investigation have demonstrated that the carbonaceous materials can become promising electrode candidates for SIBs. In this review, the recent progress of the sodium storage performances of carbonaceous materials, including graphite, amorphous carbon, heteroatom-doped carbon, and biomass derived carbon, are presented and the related sodium storage mechanism is also summarized. Additionally, the critical issues, challenges and perspectives are provided to further understand the carbonaceous anode materials. [ABSTRACT FROM AUTHOR]

Dark-colored rutile TiO2 nanorods doped by electroconducting Ti3+ have been obtained uniformly with an average diameter of ≈7 nm, and have been first utilized as anodes in lithium-ion batteries. They deliver a high reversible specific capacity of 185.7 mAh g-1 at 0.2 C (33.6 mA g-1) and maintain 92.1 mAh g-1 after 1000 cycles at an extremely high rate 50 C with an outstanding retention of 98.4%. Notably, the coulombic efficiency of Ti3+–TiO2 has been improved by approximately 10% compared with that of pristine rutile TiO2, which can be mainly attributed to its prompt electron transfer because of the introduction of Ti3+. Again the synergetic merits are noticed when the promoted electronic conductivity is combined with a shortened Li+ diffusion length resulting from the ultrafine nanorod structure, giving rise to the remarkable rate capabilities and extraordinary cycling stabilities for applications in fast and durable charge/discharge batteries. It is of great significance to incorporate Ti3+ into rutile TiO2 to exhibit particular electrochemical characteristics triggering an effective way to improve the energy storage properties. [ABSTRACT FROM AUTHOR]

Nonoxidative cathodically induced graphene (CIG) here incorporates conductive agents for Li4Ti5O12 (LTO) anode materials. The tailored LTO/CIG composite is fabricated by controlled hydrolysis of tetrabutyl titanate in the presence of nonoxidative defect-free cathodically induced graphene (CIG) and oxalic acid in a mixed solvent of ethanol and water, followed by hydrothermal reaction and a calcination treatment. Due to the introduction of defect-free graphene, the resulting LTO/CIG composite shows an excellent electrical conductivity (1.2 × 10−4 S cm−1) and Li+ diffusion coefficient (1.61 × 10−12 cm2 s−1). As a result, the tuned LTO/CIG composite exhibits outstanding electrochemical performance, including excellent cycling stability (the capacity retention ratios after 500 cycles at 0.5 C is 96.2%) and a remarkable rate capability (162 mAh g−1 at 10C, 126 mAh g−1 at 100 C). A specific energy of 272 Wh kg−1 at power of 136 W kg−1 is observed when cycling against Li-foil. Even during 36 s of charge/discharge, the specific energy of LTO/CIG composite remains at 166 Wh kg−1. [ABSTRACT FROM AUTHOR]

Abstract: NASICON-type Na3V2(PO4)2F3 is employed as a promising cathode for sodium-ion batteries in order to explore the ion-migration mechanism and diffusion capability. Two kinds of Na sites, namely Na(1) site and Na(2) site exist in the crystal structure per formula unit to accommodate a total of three sodium ions. The ion at Na(2) site with half occupation extracts first and inserts the last due to its high chemical potential, while the whole extraction/insertion of two ions between 1.6 and 4.6 V vs. Na+/Na can produce three plateaus in charge/discharge processes because of the reorganization of ions. The first discharge capacity of 111.6 mAh g−1 with retention of 97.6% after 50 cycles could be obtained by electrochemical testing at 0.091C. Electrochemical activation and/or structural reorganization of the system by cycling could improve the diffusion coefficient of sodium with a comparatively large magnitude of 10−12 cm2 s−1, though many influences on the resistance factors also can be attributed to the cycling process. Such work is of fundamental importance to the progression of sodium-based batteries to be fully realized and be implemented over existing Li-ion based batteries. [Copyright &y& Elsevier]

Ni-rich layered transition metal oxide is one of the most promising cathode materials for the next generation lithium-based automotive batteries due to its excellent electrochemical performances. Nevertheless, its further applications are capped by the structural/interfacial instability during the prolonged charging/discharging, leading to severe performance fading and serious safety concerns. Here, we provide a comprehensive review about challenges and solutions to modify Ni-rich layered cathodes specifically for microcrack failure. Firstly, the mechanism of microcrack formation and evolution are concluded thoroughly. Secondly, recent advances in stabilizing the structure/interface of Ni-rich cathodes are summarized such as surface coating, cation/anion doping, composition tailoring, morphology engineering and electrolytes optimization. Furthermore, strategies to mitigate the microcrack and then boost the electrochemical performance of Ni-rich cathodes at the chemical & mechanical engineering level are presented. More importantly, outlook and perspectives to facilitate the practical application of Ni-rich layered cathodes toward electrical vehicle application are provided as well. The information compiled herein can promote the understanding of the microcracks of Ni-rich cathode materials, including its fundamental science, characterization method, and strategies for designing crack-free Ni-rich cathode materials. Furthermore, we provide a new idea for material modification, which is perspective strategy from crystallographic, structural mechanics and chemistry under the guidance of "chemical-mechanical" effect. [Display omitted] • The mechanism of microcrack formation and evolution are concluded. • Recent advances in stabilizing the structure/interface of Ni-rich cathodes are summarized. • Strategies to mitigate the microcrack and then boost the electrochemical performance of Ni-rich cathodes are presented. • Main challenges and the future horizons are outlooked. [ABSTRACT FROM AUTHOR]

Secondary charge batteries have captured numerous attentions, owing to their abundant raw, portability, and high energy density. As the main ions‐storage carrier, the electrode materials serve vital roles on the properties of whole battery system. Currently, MoSe2 is regarded as rising star of transition metal dichalcogenides, displaying unique layered structure, high electronic conductivity, as well as narrow energy band. These advantages enable their widely application on hydrogen evolution reactions and solar cells. Recently, a plenty of researching activities on MoSe2/carbon are triggered due to large interplanar spacing and high ions/e− migration rate. In this review, the recent achievements of diverse MoSe2/carbon on great energy‐storage domains are solidly summarized from bonding types (surface‐loading, internal‐wrapped) and dimensional controlling (1D nanotubes/nanofibers, 2D graphene/nanosheets, 3D carbon framework/sphere). Meanwhile, the related Li/Na ions‐storage mechanisms are also concluded. Furthermore, for MoSe2/carbon with better electrochemical properties, the opportunities and perspectives in the future are also suggested. This review throws light on the systematic developments of advanced MoSe2/carbon, and confirms its exploring potential on lithium‐ion batteries/sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) are currently drawing increased attention as a promising alternative to lithium‐ion batteries (LIBs) owing to the abundant resource and low cost of potassium. However, due to the large ionic radius size of K+, electrode material that can stably maintain K+ insertion/deintercalation is still extremely inadequate, especially for anode material with a satisfactory reversible capacity. As an attempt, nitrogen/carbon dual‐doped hierarchical NiS2 is introduced as the electrode material in PIBs for the first time. Considering that the introduction of the carbon layer effectively alleviates the volume expansion of the material itself, further improves the electronic conductivity, and finally accelerates the charge transfer of K+, not surprisingly, NiS2 decorated with the bifunctional carbon (NiS2@C@C) material electrode shows excellent potassium storage performances. When utilized as a PIB anode, it delivers a high reversible capacity of 302.7 mAh g−1 at 50 mA g−1 after 100 cycles. The first coulombic efficiency is 78.6% and rate performance is 151.2 mAh g−1 at 1.6 A g−1 of the NiS2@C@C, which are also notable. Given such remarkable electrochemical properties, this work is expected to provide more possibilities for the reasonable design of advanced electrode materials for metal sulfide potassium ion batteries. [ABSTRACT FROM AUTHOR]

Lithium metal is the most ideal anode for next‐generation lithium‐ion batteries. However, the formation of lithium dendrites and the continuous consumption of electrolyte during cycling lead to a serious safety problems. Developing stable lithium metal anode with uniform lithium deposition is highly desirable. Herein, a nitrogen plasma strengthening strategy is proposed for copper oxide nanosheet–decorated Cu foil as an advanced current collector, and deep insights into the plasma regulating mechanism are elaborated. The plasma‐treated electrode can maintain a high coulombic efficiency of 99.6% for 500 cycles. The symmetric cell using the lithium‐plated electrode can be cycled for more than 600 h with a low‐voltage hysteresis (23.1 mV), which is much better than those of electrodes without plasma treatment. It is well confirmed that this plasma‐induced nitrogen doping method can provide sufficient active sites for lithium nucleation to enhance the stability of lithium deposition on copper oxide nanosheets decorated on Cu foil and improve the electrical conductivity to greatly reduce the overpotential of the lithium nucleation, which can be extended to other modified current collectors for stable lithium metal anode. [ABSTRACT FROM AUTHOR]

Layered lithium transition‐metal oxides are considered as promising cathodes for new‐generation lithium‐ion batteries due to their high capacity and excellent rate capability. Nevertheless, the approach of preparing precursors is generally restricted to the utilization of wet‐chemical methods. Herein, for the first time, an electrochemical strategy is introduced to prepare Ni1/3Mn1/3Co1/3(OH)2 precursor with the mixing at the atomic level by electrochemically anodized Ni–Mn–Co alloy anode, demonstrating the superiorities of high yield without the process of the extreme alkaline environment and complicated process. Furthermore, the layered LiNi1/3Mn1/3Co1/3O2 cathode is obtained through calcining the mixture of precursors and Li sources under a certain calcined temperature. As anticipated, the initial discharge specific capacities of 183.9 mAh g−1 at 0.1 C with a capacity retention of 79.66% after 120 loops are delivered for LiNi1/3Mn1/3Co1/3O2 cathode with calcining at 930 °C, and it also exhibits superior rate capability with specific capacities of 151.1 and 116.5 mAh g−1 at 1 and 10 C, respectively. Therefore, this innovative approach can be readily extended to prepare other types of lithiated transition metal oxide precursors. [ABSTRACT FROM AUTHOR]

Lithium‐ion hybrid supercapacitors (LICs) are considered as a promising candidate in energy storage systems. Taking the factor of sluggish kinetics behavior, battery‐type anode plays a significant role in improving the performance of LICs. Here, onion‐shaped graphene‐like derivatives are synthesized via carbonization of metalorganic quantum dots (MQDs) accompanied with in situ catalytic graphitization by reduced metal. Notably MQDs, exhibiting water‐soluble character and ultrafine particles (2.5–5.5 nm) morphology, are prepared by the amidation reaction. The carbonized sample exhibits highly graphitic tendency with graphitization degree up to 95.6%, and shows graphene‐like porous structure, appropriate amorphous carbon decoration characteristic, as well as N‐doping and defective nature. When employed as anode material in LICs, it shows high energy density of 83.7 Wh kg–1 and high power density of 6527 W kg–1 when the mass ratio of cathode to anode is 1:1 and the operating voltage ranges from 2.0 to 4.0 V. It also possesses the long cyclic stability with the energy density retention maintains at 97.3% after 10 000 cycles at 5.0 A g–1. In addition, the energy density is further increased by altering cathode/anode mass ratio and extending working voltage. This work provides a novel strategy to develop unique carbon materials for energy storage. Water‐soluble metalorganic quantum dots are synthesized and their derivative porous graphitic carbons (PGCs) are achieved accompanied with in situ catalytic graphitization process. The obtained PGCs exhibit high plateau capacity and superior rate capability, making them very promising anode materials for lithium‐ion capacitors, benefiting from the high graphitization degree, graphene‐like porous shape, appropriate amorphous carbon decoration, and N‐doping and defect‐rich natures. [ABSTRACT FROM AUTHOR]

Recycling of spent lithium-ion batteries (LIBs) has emerged as an inevitable trend in promoting environmental sustainability and resource conservation. Lithium iron phosphate (LiFePO 4 or LFP) battery, renowned for its unique stability and favorable price, has been the predominant focus for lithium-ion battery manufacturers, consequently resulting in a surge in the number of spent LIBs. In view of the failure mechanism, the direct regeneration technology presents a potential strategy for the closed-loop recycling of LFP. The aim is to retain the high added value and revitalize optimal state of the spent cathode materials through a non-destructive process that maximizes efficiency and ensures desirable profits. Hence, the existing technical challenges and recent progress in the separation pretreatment are reviewed and summarized. Subsequently, the current direct regeneration methods and advanced upcycling techniques for spent LFP cathode are outlined, along with an appraisal of their respective advantages and disadvantage. Specifically, a comprehensive analysis of environmental and economic benefits derived from three presentative examples is highlighted compared to traditional metallurgy process. The review also aims to provide an overview on direct regeneration of spent LFP cathode, making it favorable for further industry adoption. • Potential strategy for low-value LFP via direct regeneration is presented. • Challenges and recent progress in separation pretreatment are discussed. • Recent advancements and advanced upcycling for spent LFP cathode are summarized. • The merits and drawbacks of each approach are assessed. • The comprehensive analysis of environmental and economic benefits is emphasized. [ABSTRACT FROM AUTHOR]

• H 2 NNS is effective for regeneration of lithium-ion electrode materials. • The leaching condition for simultaneous recovery of valuable metals are optimized. • Electrode materials with microstructure show excellent electrochemical properties. • The principle is potential for recycle of spent battery materials. The resource exhaustion and environmental assessment driven by sustainable development make recycle of spent LIBs urgent to be achieved. However, the conventional recycling processes are quite complicated in terms of the tedious steps and secondary contamination. In this paper, hydrosoluble naphthalenedisulfonic acid is firstly proposed to selectively extract valuable metals (Co and Li) for the regeneration of battery materials. Lithium is selectively recovered as lithium enriched solution with a high yield of 99%, while 96.6% cobalt remains in a complex-precipitate benefited from the high acidity and coordination role of naphthalenedisulfonic acid. The leaching of Li fits well with the logarithmic rate law model with an activation energy of 32.42 kJ/mol. Additionally, the regenerated lithium-ion battery active materials (Co 3 O 4 anode and LiCoO 2 cathode) prepared from the cobalt complex-precipitate and lithium-enriched solution exhibit excellent discharged-charged performances and rate capability. This feasible strategy assisted by multifunctional naphthalenedisulfonic acid may offer an alternative option for the simultaneous recovery of Li and Co and the rational resource utilization of spent lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The transformation of energy structure is deemed as a paramount strategy in accomplishing the ambition of carbon neutrality. Lithium-ion batteries (LIBs), as one of the most exceptional energy storage and conversion devices available, play a pivotal role in this energy revolution. However, due to the extensive production and limited lifespan of LIBs, the retirements of LIBs are set to boom in the coming years. The proper and timely recycling of these batteries are of paramount importance, from both environmental and economic perspectives. Direct cathode regeneration technology is the most promising solution for the treatment of these waste cathodes, as it enables the healing of spent cathodes with minimal energy and chemical consumption, without compromising the original structure of the cathode. Herein, we analyzed the degraded mechanisms of spent LIBs and found that relithiation and defect reparation are crucial steps for the regeneration of spent cathode materials. Various direct regeneration methods previously reported have been summarized, and their respective advantages and limitations as well as technical challenges when implemented into practical industrial applications are discussed. In addition, possible solutions to these problems are proposed, which guide the future direction for the sustainable development of the battery recycling industry. • The degraded mechanisms of spent lithium-ion batteries are summarized. • Current status on direct regeneration of spent cathodes is presented. • The advantages and limitations of direct regeneration approaches are identified. • The future directions of direct regeneration strategies were proposed. [ABSTRACT FROM AUTHOR]

The booming development of the lithium-ion battery market has aroused the transformation of people's consumption and life style. As a significant branch of lithium-ion batteries, LiFePO 4 (LFP)-type batteries has been widely employed in electric vehicles and energy storage devices due to its high safety and decent charge-discharge stability. Nevertheless, the resulted massive scrap of LFP batteries will greatly pose environmental threats and waste of resources if appropriate technical means are not adopted. The advanced recycling methods of spent LFP cathode have long been constantly explored in recent years but have not been systematically discussed. Hence, this review comprehensively summarizes the recovery technologies of spent LiFePO 4 cathode in the current status, including traditional pyro-/hydro-metallurgical processes, direct regeneration and other innovative methods, etc. Furthermore, the pretreatment process is also covered to promote all-sided understanding of the development of LFP cathode recovery approaches. Based on the systematic analysis of spent LFP cathode recycling, the future outlook of efficient recycling methods is proposed to promote the sustainable development of spent lithium-ion batteries. Schematic illustration of strategies and characteristics towards spent LFP cathode recycling. [Display omitted] • A comprehensive summary and prospect of spent LFP cathode recycling. • Pretreatment is introduced to ensure deep understanding of recycling implication. • Mainstream recycling technologies of spent LFP battery are reviewed. • Up-to-date novel recycling methods for spent LFP cathode are summarized. • Future challenges and perspectives are proposed to promote efficient recycling. [ABSTRACT FROM AUTHOR]

Na-ion batteries have gained significant attention as a cost-effective and efficient energy storage option for large scale applications, serving as an alternative to the Li-ion batteries. However, commercialization of these batteries is still many steps away since most cathode materials suffer from significant capacity loss and more full-cell studies are required. In this work, we report the electrochemical properties of half- and full-cells of P2-type Na 0.67 Mn 0.85 Cu 0.15 O 2 synthesized by solid state technique. X-ray diffraction, FT-IR, and Raman spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy techniques are used to determine the structural properties. Surface properties are studied by X-ray photoelectron spectroscopy and Brunauer–Emmett–Teller techniques. Half cells and full cells were constructed with Na-metal and hard carbon, respectively. Na-ion diffusion kinetics at 10 °C, room temperature, and 50 °C were determined experimentally. Galvanostatic cycling tests on half-cells show capacity values of 165/124 mAh/g for the 1./100. cycles with 24.8 % capacity fade. Operando x-ray absorption spectroscopy measurements were utilized to study local structural modification around transition metal ions during charge/discharge. In the full-cell studies, electrode mass ratio (p/n) and parameters for presodiation of hard carbon were optimized. Using 30 mA/g current density, the unprocessed and the pre-sodiated full-cells reach capacity values of 48 mAh/g (p/ n = 2.5) and 150 mAh/g (p/ n = 0.75 and 1.15), respectively. [ABSTRACT FROM AUTHOR]

• Propose a strategy of synergetic modulation on electrolyte and electrode interface. • Synergistically accelerate the interfacial reaction kinetics at low temperature. • Niobium oxide with high intercalation potential inhibit the generation of Li plating at low temperature. • Promising rate and cycle performance of T-Nb 2 O 5 @C||LFP at ultra-low temperature. The performance of rechargeable lithium-ion batteries (LIBs) in cold environments remains a challenge due to the insufficient ionic conductivity of electrolyte and lithium plating at graphite anodes. Herein, we demonstrate that the synergistic effect of ether-based electrolyte and niobium oxide with high intercalation potential can significantly improve the low-temperature charging/discharging performance of LIBs. Theoretical calculations and in-situ characterizations prove that the weak desolvation energy of electrolyte and the strong binding energy Li+-O bridging coordination synergistically accelerate the interfacial reaction kinetics. The full cells by coupling the niobium oxide anode with LiFePO 4 cathode show 95.6% of the initial capacity after 500 cycles at −30 °C, and exhibit excellent rechargeability at −50 °C. This work verifies that the synergism of solvating power of solvent and Li+ intercalation behavior is crucial in low-temperature LIBs. [ABSTRACT FROM AUTHOR]

Abstract Structural fabrication and modification are the effective approaches to regulate the electrochemical performances of anatase TiO 2. Herein, the template-annealing-etching processes are carried out to synthesize inverse opal TiO 2 with N-doped carbon layer and oxygen vacancies surface as an anode material for advanced lithium ion batteries and sodium ion batteries. These structural features not only shorten the diffusion paths and enhance the electronic conductivity, but also induce the dominant pseudocapacitive contribution. As a result, the as-prepared electrode exhibits the excellent Li+/Na+ storage performances, including a high capacity retention (462 mAh g−1 after 300 cycles at 0.5 A g−1) and a fast cycling capability (180 mAh g−1 after 3500 cycles under 10 A g−1) for lithium storage; a reversible capacity of 140 mAh g−1 after 400 cycles under 1 A g−1 for sodium storage. Revealed by cyclic voltammetry, the pseudocapacitive contribution is as high as 74.49% and 73.38% at 1 mV s−1 for lithium ion batteries and sodium ion batteries, respectively. This work may promise a general approach to synthesize metal oxides anode materials for advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pure lithium carbonate was recycled from spent graphite. • Graphite was regenerated by a two-stage calcination and acid leaching. • Regenerated graphite has impressive electrochemical performances. Abstract Recycling lithium and graphite from spent lithium-ion battery plays a significant role in mitigation of lithium resources shortage, comprehensive utilization of spent anode graphite and environmental protection. In this study, spent graphite was firstly collected by a two-stage calcination. Secondly, under the optimal conditions of 1.5 M HCI, 60 min and solid-liquid ratio (S/L) of 100 g·L−1, the collected graphite suffers simple acid leaching to make almost 100% lithium, copper and aluminum in it into leach liquor. Thirdly, 99.9% aluminum and 99.9% copper were removed from leach liquor by adjusting pH first to 7 and then to 9, and thenthe lithium was recovered by adding sodium carbonate in leach liquor to form lithium carbonate with high purity (>99%). The regenerated graphite is found to have high initial specific capacity at the rate of 37.2 mA·g−1 (591 mAh·g−1), 74.4 mA·g−1 (510 mAh·g−1) and 186 mA·g−1 (335 mAh·g−1), and with the high retention ratio of 97.9% after 100 cycles, it also displays excellent cycle performance at high rate of 372 mA·g−1. By this process, copper and lithium can be recovered and graphite can be regenerated, serving as a sustainable approach for the comprehensive utilization of anode material from spent lithium-ion battery. [ABSTRACT FROM AUTHOR]

By reason of rich sodium resources, sodium-ion batteries have excited enormous consideration for adhibition in the developing energy-storage stations. And not surprisingly, the exploration of cost-effective anode materials for SIBs have been a conspicuous topic. Herein, iron trioxide embedded in the nitrogen-doped carbon matrix with strong oxygen-bridge bonds is synthesized by using the iron based metal organic framework as template. The obtained composite delivers excellent electrochemical properties, such as specific capacity of 473.7 mAh g −1 at the current density of 100 mA g −1 after 100 cycles. Besides, the reversible capacity still remains at 155.3 mAh g −1 at the high density of 4000 mA g −1 . This remarkable sodium-ion storage capability could be attributed to the incorporation of nitrogen atoms into carbon matrix and the strong chemical bonds between iron trioxide and carbon matrix, which can restrain electrode pulverization and also retain an interparticle connection even after long cycling that could offer a good electronic conductive pathway. This engineer strategy for preparing iron trioxide possess strong interfacial interaction with nitrogen-doped carbon matrix can be applied to other metal phosphides and metal oxide materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • C 6 H 12 O 6 as a reagent resulted in LiCoO 2 reduction at low temperature (<550 °C). • LiCoO 2 reduction mechanisms have been determined by thermodynamic calculations. • 97% of Li can be selective leached out by using water as the only leaching reagent. • The recovered Li 2 CO 3 and Co 3 O 4 could be directly used for cathode regeneration. • The proposed closed-loop process mitigates energy consumption, pollution and costs. Due to the mounting pressure to mitigate environmental pollution and guarantee the sustainability of the battery metals, the recycling of spent lithium-ion batteries (LIBs) has become a crucial issue in recent years. Numerous studies have focused on utilizing high temperatures or strong acid/alkali to reduce the spent active cathode material to a low valence state, which exacerbates recycling and post-treatment costs. Herein, a low-temperature roasting process followed by a water leaching strategy is developed to recycle and regenerate LiCoO 2 cathode material from spent LiCoO 2 batteries. The spent LiCoO 2 is roasted with glucose (C 6 H 12 O 6) as a reagent to attain reduction of the cathode material into water-soluble Li salt (Li 2 O and Li 2 CO 3) and water-insoluble (Co and CoO). The proposed method utilizes moderate roasting temperature and water as the only leaching reagent, which effectively reduces energy and chemical consumption. Li and Co recovery rates are 97 % and 99 %, respectively, under the optimal conditions of 1 h roasting at 550 °C followed by 30 min water leaching using a solid–liquid ratio of 50 g/L. The recovered Li-rich solution and Co-rich residue can be easily converted to Li 2 CO 3 and Co 3 O 4 , respectively, which are the precursors for regenerating the LiCoO 2 cathode material. The regenerated LiCoO 2 exhibits superior cycling stability with 87 % capacity retention after 800 cycles at 4.4 V. This developed closed-loop recycling process has lower recycling costs, is eco-friendly and efficient, and thus could potentially promote the sustainable long-run development of the LIBs industry. [ABSTRACT FROM AUTHOR]

Different sulfide species of both iron and cobalt metals (FeS 2 , FeS, CoS, and FeCoS 2) are composed together in N-doped porous carbon (NPC) for the synthesis of composite anode materials (labeled as Fe/Co/S@NPC-T hereafter, T = 700, 800, 900) by sulfurization and pyrolysis of Fe/Co-based zeolitic imidazolate framework (ZIF-12). Their structural properties are investigated by XRD, FTIR, SEM, TEM, BET and XPS analysis, and Fe/Co/S@NPC-T composite materials, heat treated at different temperatures, are used as anode materials in rechargeable lithium-ion batteries. According to XRD results, the heat treatment of the Fe/Co@ZIF-12/S heat treated at 900 °C leads to the formation of the FeCoS 2 phase (66 %) along with CoS (33 %) phase impurity. The heat treatment of the Fe/Co@ZIF-12/S heat treated at 800 °C causes the formation of the main phase of FeCoS 2 with minor impurity phases of CoS and FeS 2. However, pyrolysis of the Fe/Co@ZIF-12/S heat treated at 700 °C leads to the formation of the FeCoS 2 , CoS, FeS, and FeS 2 phases. Among the samples, the highest BET surface area is 53.4 m2/g for the Fe/Co/S@NPC-900 sample. The CV analysis of the battery cell shows anodic and cathodic redox peaks, which belong to the redox reaction of CoS, FeS 2, and FeS. The first discharge capacities of the cells for Fe/Co/S@NPC-700, Fe/Co/S@NPC-800 and Fe/Co/S@NPC-900 are 395, 963, 574 mA h/g at 300 mA/g, and 229, 835 and 1024 mA h/g at 1000 mA/g, respectively. [Display omitted] • Fe/Co/S/@ZIF-12-C-T composite structures were used as anode material on Li-ion battery cells. • The electrochemical properties of Fe/Co/S/@C-T show high performance as ana anode materials. • It was achieved the capacity of 1024 mA h/g at 1000 mA/g which is promising results for the commercial applications. [ABSTRACT FROM AUTHOR]

Three-dimensional copper oxide structures composed of single crystal nanosheets have been successfully prepared by a green electrochemical alternating voltage approach. This special structure of copper oxide grown along the [0 1 0] direction can be effective to accommodate the volume expansion during charge–discharge cycles. The obtained product as anode materials in lithium-ion batteries displays outstanding electrochemical performances with a high reversible capacity of 635.2 mA h g −1 after 50 cycles at 100 mA g −1 close to the theoretical capacity of copper oxide (674 mA h g −1 ). [ABSTRACT FROM AUTHOR]

Cathodic corrosion, a green electrochemical method, has been employed to obtain Sb nanomaterials utilized as anode material for lithium-ion batteries and sodium-ion batteries. Interestingly, two different corrosion mechanisms are found, coming from the impact of electrolyte, resulting in the formation of hexagonal and amorphous Sb in aqueous and organic solution, respectively. With the help of water-soluble carboxymethyl cellulose binder and the electrolyte additive fluoroethylene carbonate, both hexagonal and amorphous Sb electrodes exhibit good cycling stability when utilized as anode materials for lithium-ion batteries and sodium-ion batteries. Additionally, both the hexagonal and amorphous Sb electrodes show very good rate capability in lithium-ion batteries. Even at high current density (2000 mA g −1 ), the hexagonal and amorphous Sb give reversible capacities of 422 and 379 mA h g −1 , respectively. Surprisingly, when used as anode materials for sodium-ion batteries, the hexagonal Sb electrode exhibits a good rate performance of 632, 625, 569, 515 and 426 mA h g −1 at a current density of 100, 200, 500, 1000, and 2000 mA g −1 , respectively. However, limited rate performance is observed from the amorphous Sb electrode in case of sodium-ion battery due to the large impedance. [ABSTRACT FROM AUTHOR]

A novel and facile in-situ methodology has been developed to prepare well carbon-coated anatase titanium dioxide (TiO 2 ) nanoparticles. The hydrolysis of tetrabutyl titanate has been effectively controlled in a collosol of N-methyl-2-pyrrolidone dissolved with polyvinylidene fluoride. The as-resulted carbon-dispersed TiO 2 nanoparticles distributed in ranges from 20 to 30 nm in diameter have been obtained with a carbon content of 11.7 wt%. This nanocomposite utilized as anode materials in lithium-ion battery can deliver a high reversible specific capacity of 218 mAh g −1 at the current density of 0.2 C (33.5 mA g −1 ), and still exhibit 100 mAh g −1 at 10 C (1.68 A g −1 ), illustrating notable high-rate performances for the potential application in fast charge/discharge batteries. [ABSTRACT FROM AUTHOR]

Mn 3 O 4 /graphite powder (Mn 3 O 4 /GhP) composite was successfully obtained utilizing an alternating voltage induced electrochemical method. It was found that Mn 3 O 4 particles (∼20 nm) resulted from Mn electrodes were well dispersed on the surface of GhP. The electrochemical performances of Mn 3 O 4 /GhP material as anode for lithium-ion batteries were investigated, demonstrating high specific capacity and excellent cycling stability with a high charge-discharge capacity of 1007.4 mAh g −1 after 50 cycles at a current density of 100 mA g −1 . [ABSTRACT FROM AUTHOR]

NASICON Na 3 V 2 (PO 4 ) 3 and Na 3 V 2 (PO 4 ) 2 F 3 have restarted to be investigated electrochemically as promising cathode materials for sodium-ion batteries. Fluorine insertion by replacing partial phosphate groups in Na 3 V 2 (PO 4 ) 3 allows for new family of host lattice structure, Na 3 V 2 (PO 4 ) 2 F 3 . Greatly, fluorine is capable to participate in structural construction to change the ions configuration which involves ions occupation, the species and amount of diverse Na sites, leading to distinct modalities for ions extraction. The inductive effects of (PO 4 ) 3− polyanion by changing electronic cloud density upon compositional atoms could be enhanced under the effects of the formed F-V bond due to its strong ionicity, which can moderate the energetics of the transition metal redox couple to generate relatively high operating potentials. The substitution of fluorine for negative-charge polyanion or anion could be effective to improve the electrochemical properties, particularly for the purpose to increase performed voltages by changing atomic environments. [ABSTRACT FROM AUTHOR]

An electrochemical collision method focusing on individual particles is applied to investigate the LiNi 0.8 Mn 0.1 Co 0.1 O 2 for direct and accurate information about the ions migration process. For the first time, two types of unique current signals including trapezoid-like signals and wider-wave signals are observed with the increase of particle sizes, except for the acquainted spike-like signals with a sharp rise and a slow decay. The trapezoid-like signals started with a slow rise following by a steady platform and a slow decay, revealing an out-of-sync reaction at the beginning and a subsequent interface traversing and internal ion diffusion jointly controlled ions migration process in the particle. The wider-wave signals with a slower rise and a much slower decay are acquired from particles with the largest size, showing the slowest kinetics during the whole reaction process in the particle. [Display omitted] • The de-insertion process of Li+ in single LiNi 0.8 Mn 0.1 Co 0.1 O 2 is studied. • Ion diffusion process changes with particle size. • Current signals with specific feature is found for the first time. • Ion diffusion inside the particle/cross the interface determine the rate capability. [ABSTRACT FROM AUTHOR]

ZnS has high theoretical capacity (962.3 mAh·g−1) and low discharge platform. However, it has poor electrical conductivity and cycling performance for lithium-ion batteries (LIBs). In this study, a natural mineral of ZnS doped with iron called marmatite was discovered. Results indicated that this natural marmatite has a structure similar to that of the ZnS of the Td2-F4-3m space group and also has low discharge platform (<1 V). Compared with pristine, the natural marmatite has superior electrochemical stability (After 1000 cycles at a current density of 2000 mA g−1, a capacity of 651 mAh·g−1 with a reversible capacity retention rate of 94% remained.) and higher capacity (1009 mAh·g−1 at a current density of 200 mA g−1). These results indicated that the natural marmatite exhibits high capacity and excellent cycle performance, demonstrating unique potential for next-generation LIBs. Image 1010 [ABSTRACT FROM AUTHOR]