A novel carbon-coated LiCoO2 as cathode material for lithium ion battery

MoS2 Hollow Multishelled Nanospheres Doped Fe Single Atoms Capable of Fast Phase Transformation for Fast-charging Na-ion Batteries

Low Na+ and electron diffusion kinetics severely restrain the rate capability of MoS2 as anode for sodium-ion batteries (SIBs). Slow phase transitions between 2H and 1T, and from NaxMoS2 to Mo and Na2S as well as the volume change during cycling, induce a poor cycling stability. Herein, an original Fe single atom doped MoS2 hollow multishelled structure (HoMS) is designed for the first time to address the above challenges. The Fe single atom in MoS2 promotes the electron transfer, companying with shortened charge diffusion path from unique HoMS, thereby achieving excellent rate capability. The strong adsorption with Na+ and self-catalysis of Fe single atom facilitates the reversible conversion between 2H and 1T, and from NaxMoS2 to Mo and Na2S. Moreover, the buffering effect of HoMS on volume change during cycling improves the cyclic stability. Consequently, the Fe single atom doped MoS2 quadruple-shelled sphere exhibits a high specific capacity of 213.3 mAh g-1 at an ultrahigh current density of 30 A g-1, which is superior to previously-reported results. Even at 5 A g-1, 259.4 mAh g-1 (83.68 %) was reserved after 500 cycles. Such elaborate catalytic site decorated HoMS is also promising to realize other "fast-charging" high-energy-density rechargeable batteries.

Carbon supported ternary layered double hydroxide nanocomposite for Fluoxetine removal and subsequent utilization of spent adsorbent as antidepressant

Fluoxetine (FLX) is one of the most persistent pharmaceuticals found in wastewater due to increased use of antidepressant drugs in recent decades. In this study, a nanocomposite of ternary ZnCoAl layered double hydroxide supported on activated carbon (LAC) was used as an adsorbent for FLX in wastewater effluents. The nanocomposite was characterized using Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and surface area analysis (BET). The adsorption investigations showed that the maximum removal capacity was achieved at pH 10, with a 0.1 g/L adsorbent dose, 50 mL volume of solution, and at a temperature of 25 °C. The FLX adsorption process followed the Langmuir-Freundlich model with a maximum adsorption capacity of 450.92 mg/g at FLX concentration of 50 µg/mL. Density functional theory (DFT) computations were used to study the adsorption mechanism of FLX and its protonated species. The safety and toxicity of the nanocomposite formed from the adsorption of FLX onto LAC (FLX-LAC) was investigated in male albino rats. Acute toxicity was evaluated using probit analysis after 2, 6, and 24 h to determine LD50 and LD100 values in a rat model. The FLX-LAC (20 mg/kg) significantly increased and lengthened the sleep time of the rats, which is important, especially with commonly used antidepressants, compared to the pure standard FLX (7 mg/kg), regular thiopental sodium medicine (30 mg/kg), and LAC alone (9 mg/kg). This study demonstrated the safety and longer sleeping duration in insomniac patients after single-dose therapy with FLX-LAC. Selective serotonin reuptake inhibitors (SSRIs) like FLX were found to have decreased side effects and were considered the first-line mood disorder therapies.

Dual Strategies with Anion/Cation Co-Doping and Lithium Carbonate Coating to Enhance the Electrochemical Performance of Lithium-Rich Layered Oxides

Lithium-rich layered oxides (LLOs, Li1.2 Mn0.54 Ni0.13 Co0.13 O2 ) are widely used as cathode materials for lithium-ion batteries due to its high specific capacity, high operating voltage and low cost. However, the LLOs are faced with rapid decay of charge/discharge capacity and voltage, as well as interface side reactions, which limit its electrochemical performance. Herein, the dual strategies of sulfite/sodium ion co-doping and lithium carbonate coating were used to improve it. It founds that modified LLOs achieve 88.74 % initial coulomb efficiency, 295.3 mAh g-1 first turn discharge capacity, in addition to 216.9 mAh g-1 at 1 C, and 87.23 % capacity retention after 100 cycles. Mechanism research indicated that the excellent electrochemical performance benefits from the doping of both Na+ and SO3 2- , and it could significantly reduce the migration energy barrier of Li+ and promote Li+ migration. Meanwhile, anion and cation are co-doped greatly reduces the band gap of LLOs and increase its electrical conductivity, and its binding effect on Li+ is weakened, making it easier for Li+ to shuttle through the material. In addition, the lithium carbonate coating significantly inhibits the occurrence of interfacial side reactions of LLOs. This work provides a theoretical basis and practical guidance for the further development of LLOs with higher electrochemical performance.

Aqueous Cold Sintering of Li-Based Compounds

Aqueous cold sintering of two lithium-based compounds, the electrolyte Li_6.25La₃Zr₂Al_0.25O₁₂ (LLZAO) and cathode material LiCoO₂ (LCO), is reported. For LLZAO, a relative density of ∼87% was achieved, whereas LCO was sintered to ∼95% with 20 wt % LLZAO as a flux/binder. As-cold sintered LLZAO exhibited a low total conductivity (10^-8 S/cm) attributed to an insulating grain boundary blocking layer of Li₂CO₃. The blocking layer was reduced with a post-annealing process or, more effectively, by replacing deionized water with 5 M LiCl during cold sintering to achieve a total conductivity of ∼3 × 10^-5 S/cm (similar to the bulk conductivity). For LCO-LLZAO composites, scanning electron microscopy and X-ray computer tomography indicated a continuous LCO matrix with the LLZAO phase evenly distributed but isolated throughout the ceramics. [001] texturing during cold sintering resulted in an order of magnitude difference in electronic conductivity between directions perpendicular and parallel to the c-axis at room temperature. The electronic conductivity (∼10^-2 S/cm) of cold sintered LCO-LLZAO ceramics at room temperature was comparable to that of single crystals and higher than those synthesized via either conventional sintering or hot pressing.

Quantum view of Li-ion high mobility at carbon-coated cathode interfaces

Lithium-ion batteries (LIBs) are among the most promising power sources for electric vehicles, portable electronics and smart grids. In LIBs, the cathode is a major bottleneck, with a particular reference to its low electrical conductivity and Li-ion diffusivity. The coating with carbon layers is generally employed to enhance the electrical conductivity and to protect the active material from degradation during operation. Here, we demonstrate that this layer has a primary role in the lithium diffusivity into the cathode nanoparticles. Positron is a useful quantum probe at the electroactive materials/carbon interface to sense the mobility of Li-ion. Broadband electrical spectroscopy demonstrates that only a small number of Li-ions are moving, and that their diffusion strongly depends on the type of carbon additive. Positron annihilation and broadband electrical spectroscopies are crucial complementary tools to investigate the electronic effect of the carbon phase on the cathode performance and Li-ion dynamics in electroactive materials.

Carbon-Coatings Improve Performance of Li-Ion Battery

The development of lithium-ion batteries largely relies on the cathode and anode materials. In particular, the optimization of cathode materials plays an extremely important role in improving the performance of lithium-ion batteries, such as specific capacity or cycling stability. Carbon coating modifying the surface of cathode materials is regarded as an effective strategy that meets the demand of Lithium-ion battery cathodes. This work mainly reviews the modification mechanism and method of carbon coating, and summarizes the recent progress of carbon coating on some typical cathode materials (LiFePO₄, LiMn₂O₄, LiCoO₂, NCA (LiNiCoAlO₂) and NCM (LiNiMnCoO₂)). In addition, the limitations of the carbon coating on the cathode are also introduced. Suggestions on improving the effectiveness of carbon coating for future study are also presented.

Interfacial Design for a 4.6 V High-Voltage Single-Crystalline LiCoO2 Cathode

Single-crystalline cathode materials have attracted intensive interest in offering greater capacity retention than their polycrystalline counterparts by reducing material surfaces and phase boundaries. However, the single-crystalline LiCoO₂ suffers severe structural instability and capacity fading when charged to high voltages (4.6 V) due to Co element dissolution and O loss, crack formation, and subsequent electrolyte penetration. Herein, by forming a robust cathode electrolyte interphase (CEI) in an all-fluorinated electrolyte, reversible planar gliding along the (003) plane in a single-crystalline LiCoO₂ cathode is protected due to the prevention of element dissolution and electrolyte penetration. The robust CEI effectively controls the performance fading issue of the single-crystalline cathode at a high operating voltage of 4.6 V, providing new insights for improved electrolyte design of high-energy-density battery cathode materials.

Oxygen Loss in Layered Oxide Cathodes for Li-Ion Batteries: Mechanisms, Effects, and Mitigation

Layered lithium transition metal oxides derived from LiMO₂ (M = Co, Ni, Mn, etc.) have been widely adopted as the cathodes of Li-ion batteries for portable electronics, electric vehicles, and energy storage. Oxygen loss in the layered oxides is one of the major factors leading to cycling-induced structural degradation and its associated fade in electrochemical performance. Herein, we review recent progress in understanding the phenomena of oxygen loss and the resulting structural degradation in layered oxide cathodes. We first present the major driving forces leading to the oxygen loss and then describe the associated structural degradation resulting from the oxygen loss. We follow this analysis with a discussion of the kinetic pathways that enable oxygen loss, and then we address the resulting electrochemical fade. Finally, we review the possible approaches toward mitigating oxygen loss and the associated electrochemical fade as well as detail novel analytical methods for probing the oxygen loss.

Nanoporous Co and N-Codoped Carbon Composite Derived from ZIF-67 for High-Performance Lithium-Sulfur Batteries

Lithium-sulfur (Li-S) batteries have nice prospects because of their excellent energy density and theoretical specific capacity. However, the dissolution of lithium polysulfides and shuttle effects lead to a low coulombic efficiency and cycle performance of Li-S batteries. Therefore, designing electrode materials that can suppress the shuttle effect and adsorb polysulfides is of great significance. In this work, a Co and N-codoped carbon composite via heating a type of Co-etched zeolitic imidazolate framework-67 (ZIF-67), nanocube precursor, in inert gas is reported as a cathode sulfur carrier material for Li-S batteries. The experimental results show that high-temperature carbonization results in mesoporous structures inside the material which not only provide ion channels for the reaction but also improve the adsorption capacity of polysulfides. Furthermore, the exposed metal Co sites and N atoms can also inhibit the shuttle effect. When the annealing temperature is 600 °C, the sulfur composite exhibits a good cycling stability and rate performance. The cathode showed an improved initial specific capability of 1042 and still maintained 477 mAh g⁻¹ at the rate of 1 C (1 C = 1672 mA g⁻¹). Furthermore, at 5 C, a stable specific discharge capacity of 608 mAh g⁻¹ was obtained.

Recent Advances in Silicon-Based Electrodes: From Fundamental Research toward Practical Applications

The increasing demand for higher-energy-density batteries driven by advancements in electric vehicles, hybrid electric vehicles, and portable electronic devices necessitates the development of alternative anode materials with a specific capacity beyond that of traditional graphite anodes. Here, the state-of-the-art developments made in the rational design of Si-based electrodes and their progression toward practical application are presented. First, a comprehensive overview of fundamental electrochemistry and selected critical challenges is given, including their large volume expansion, unstable solid electrolyte interface (SEI) growth, low initial Coulombic efficiency, low areal capacity, and safety issues. Second, the principles of potential solutions including nanoarchitectured construction, surface/interface engineering, novel binder and electrolyte design, and designing the whole electrode for stability are discussed in detail. Third, applications for Si-based anodes beyond LIBs are highlighted, specifically noting their promise in configurations of Li-S batteries and all-solid-state batteries. Fourth, the electrochemical reaction process, structural evolution, and degradation mechanisms are systematically investigated by advanced in situ and operando characterizations. Finally, the future trends and perspectives with an emphasis on commercialization of Si-based electrodes are provided. Si-based anode materials will be key in helping keep up with the demands for higher energy density in the coming decades.

Coprecipitation Temperature Effects of Morphology-Controlled Nickel Hexacyanoferrate on the Electrochemical Performance in Aqueous Sodium-Ion Batteries

Coprecipitation effortlessly fabricated nickel hexacyanoferrate (NiHCF) with outstanding rate capability and stability for aqueous batteries. Citrate-aided coprecipitation decelerated the crystallization, assembling cubic-shaped powder based on separation between nucleation and growth. This study revealed that coprecipitation temperature determined the electrochemical performance. With lower temperatures, smaller particles with more water were formed by predominant nucleation, resulting in low crystallinity and capacity of 58 mAh g^-1 . Expanded surface area reduced electrode/electrolyte interface charge-transfer resistance and showed excellent rate capability (79 % of initial capacity at 100 C-rate). However, poor cyclability was obtained. At elevated temperatures, nuclei growth and dehydration occurred, and thus highly crystalline large particles were formed. In turn, NiHCF delivered excellent capacity of 76 mAh g^-1 at 1 C-rate but exhibited inferior rate performance because of longer diffusional path. Meanwhile, normal coprecipitation at 70 °C induced irregular-shaped tiny particles, presenting 93 % retention of initial capacity at 100 C-rate.

Flower-like NiO/ZnO hybrid coated with N-doped carbon layer derived from metal-organic hybrid frameworks as novel anode material for high performance sodium-ion batteries

Metal-organic hybrid frameworks are considered as the promising precursor to prepare high performance anode materials for sodium-ion batteries (SIBs). In the present work, flower-like NiO/ZnO@NC with hollow and porous structure was prepared via a facile solvothermal and calcination process. The hollow and porous structure not only improve the electron transport capability, and but also inhibits the aggregation and accommodates the volume change of NiO/ZnO@NC. Meanwhile, the coated amorphous carbon layer could also increase the electron conductivity and buffer the huge volume expansion of active material NiO/ZnO. When used as anode for SIBs, NiO/ZnO@NC demonstrates a high specific capacity of 300 mAh g^-1 with good cycling stability for 150 cycles, fast charge and discharge capability (154 mAh g^-1 at 2500 mA g^-1) and superior long cycling life at high current density for 2500 cycles. The strategy in this work should provide a new insight into fabrication novel structural anode materials for high performance SIBs.

Crystal reconstruction of binary oxide hexagonal nanoplates: monocrystalline formation mechanism and high rate lithium-ion battery applications

Structural design and/or carbon modification are the most important strategies to improve the performance of materials in many applications, where metal (oxide)-based anode design attracts great attention in metal ion batteries due to their high capacities. However, achieving these two goals within one-step remains challenging due to the lower cost and higher efficiency needed to satisfy the demand in practical application. Herein, we report a new approach for the crystal reconstruction of metal oxides by acetylene treatment, in which a hierarchical binary oxide decorated with carbon (i.e., Mn2Mo3O8@C) is introduced. The mechanism of constructing unique monocrystalline hexagonal nanoplates and uniform carbon coating is discussed in detail. Benefiting from the uniqueness of structure and composition, the Mn2Mo3O8@C demonstrates an extremely high lithium storage capacity of 890 mA h g-1 and good rate capacities at 20 A g-1 over 1000 cycles. In addition, the high rate capabilities and long cycle lifespan are further confirmed when the Mn2Mo3O8@C anode is matched with the nickel-rich layered oxide cathode. This study not only introduces a new binary oxide anode with high performances in lithium (ion) batteries but also presents a convenient methodology to design more advanced functional materials.

Applications of Lithium-Ion Batteries in Grid-Scale Energy Storage Systems

In the electrical energy transformation process, the grid-level energy storage system plays an essential role in balancing power generation and utilization. Batteries have considerable potential for application to grid-level energy storage systems because of their rapid response, modularization, and flexible installation. Among several battery technologies, lithium-ion batteries (LIBs) exhibit high energy efficiency, long cycle life, and relatively high energy density. In this perspective, the properties of LIBs, including their operation mechanism, battery design and construction, and advantages and disadvantages, have been analyzed in detail. Moreover, the performance of LIBs applied to grid-level energy storage systems is analyzed in terms of the following grid services: (1) frequency regulation; (2) peak shifting; (3) integration with renewable energy sources; and (4) power management. In addition, the challenges encountered in the application of LIBs are discussed and possible research directions aimed at overcoming these challenges are proposed to provide insight into the development of grid-level energy storage systems.

Revisiting Electrochemical Techniques to Characterize the Solid-State Diffusion Mechanism in Lithium-Ion Batteries

Lithium-ion batteries (LiBs) have gained a worldwide position as energy storage devices due to their high energy density, power density and cycle life. Nevertheless, these performance parameters are yet insufficient for current and future demands diversifying their range of applications, and competitiveness against other power sources. In line with the materials science, the optimization of LiBs, first, requires an in-depth characterization and understanding of their determining steps regarding transport phenomena and electrode kinetics occurring within these devices. Experimental and theoretical studies have identified the solid-state diffusion of Li+into the composite cathode material as one of the transport mechanisms limiting the performance of LiBs, in particular at high charge and discharge rates (C-rates). Nowadays, there is however ambivalence to characterize this mass transport mechanism using the diffusion coefficient calculated either by electrochemical techniques orab initioquantum chemistry methods.  This contribution revisits conventional electrochemical methodologies employed in literature to estimate mass transport diffusivity of LiBs, in particular using LiFePO4in the cathode, and their suitability and reliability are comprehensively discussed. These experimental and theoretical methods include Galvanostatic and Potentiostatic Intermittent Titration Technique (GITT and PITT), Electrochemical Impedance Spectroscopy (EIS), Cyclic Voltammetry (CV) andab initioquantum chemistry methods. On the one hand, experimental methods seem not to isolate the diffusion mechanism in the solid phase; thus, obtaining an unreliable apparent diffusion coefficient (ranging from 10–10to 10–16 cm2 s−1), which only serves as a criterion to discard among a set of LiBs. On the other hand, atomistic approaches based onab initio, density functional theory (DFT), cannot yet capture the complexity of the local environments involved at this scale; in consequence, these approaches have predicted inadequate diffusion coefficients for LiFePO4(ranging from 10–6to 10–7 cm2 s−1) which strongly differ from experimental values. This contribution, at long last, remarks the factors influencing diffusion mechanisms and addresses the uncertainties to characterize this transport mechanism in the cathode, stressing the needs to establish methods to determine the diffusion coefficient accurately, coupling electrochemical techniques,ab initiomethods, and engineering approaches based on modeling.

δ-MnO2 nanoflower/graphite cathode for rechargeable aqueous zinc ion batteries

Manganese oxide (MnO2) is one of the most promising intercalation cathode materials for zinc ion batteries (ZIBs). Specifically, a layered type delta manganese dioxide (δ-MnO2) allows reversible insertion/extraction of Zn2+ ions and exhibits high storage capacity of Zn2+ ions. However, a poor conductivity of δ-MnO2, as well as other crystallographic forms, limits its potential applications. This study focuses on δ-MnO2 with nanoflower structure supported on graphite flake, namely MNG, for use as an intercalation host material of rechargeable aqueous ZIBs. Pristine δ-MnO2 nanoflowers and MNG were synthesized and examined using X-ray diffraction, electron spectroscopy, and electrochemical techniques. Also, performances of the batteries with the pristine δ-MnO2 nanoflowers and MNG cathodes were studied in CR2032 coin cells. MNG exhibits a fast insertion/extraction of Zn2+ ions with diffusion scheme and pseudocapacitive behavior. The battery using MNG cathode exhibited a high initial discharge capacity of 235 mAh/g at 200 mA/g specific current density compared to 130 mAh/g which is displayed by the pristine δ-MnO2 cathode at the same specific current density. MNG demonstrated superior electrical conductivity compared to the pristine δ-MnO2. The results obtained pave the way for improving the electrical conductivity of MnO2 by using graphite flake support. The graphite flake support significantly improved performances of ZIBs and made them attractive for use in a wide variety of energy applications.

An all manganese-based oxide nanocrystal cathode and anode for high performance lithium-ion full cells

Manganese oxide nanocrystals are of great interest for producing advanced high-performance lithium ion batteries owing to the shortened lithium ion diffusion length and accelerated interfacial charge transfer rate. Here we have developed a well-controlled generic method to synthesize monodisperse MnO nanocrystals, and present a comparative study regarding the effect of crystallite size on electrochemical stability. Nanocrystalline MnO with a size of about 10 nm shows the optimal lithium-storage performance. Notably, Mn-based nanocrystals retain their stable cyclability and excellent high-rate performance as both the anode and cathode. The all-nanocrystal MnO/C//LMO Li-ion full cells not only significantly improve the electrochemical properties of Mn-based materials but also open up avenues for the future development of various energy devices.

ZIF-67-Derived N-Doped Co/C Nanocubes as High-Performance Anode Materials for Lithium-Ion Batteries

Co nanoparticles embedded in nitrogen-doped carbon nanocubes (Co/NCs) for applications as anode materials in rechargeable lithium-ion batteries were synthesized by calcining Co-based metal-organic framework. Sizes of Co nanoparticles were ∼15 nm according to X-ray diffraction (XRD) and transmission electron microscopy. Electrochemical performances of the as-prepared anode nanocube composite at 700 °C showed a high initial capacity of 1375.1 mAh g^-1 in the voltage range of 0.01-3.0 V at the current rate of 0.1 A g^-1. After 100 cycles, capacity remained at 688.6 mAh g^-1. Thereinto, the role of Co nanoparticles in electrochemical reaction was also elucidated by in situ XRD experiment. Capacity increase of Co/NCs at the high currents was observed, which are potentially caused by the activation of electrode and pseudocapacitance during cycling. High surface area and abundant mesopores contributed to the improved electrochemical performances of the anode, providing numerous pathways and sites for Li⁺ transfer and storage and accordingly contributing to pseudocapacitance capacity.

Efficient catalytic removal of airborne ozone under ambient conditions over manganese oxides immobilized on carbon nanotubes

MnO_x–CNT nanocomposites are efficient towards ozone decomposition owing to the electron transfer from the CNTs to MnO_x that facilitates the activation of ozone.

LiCrO2 Under Pressure: In-Situ Structural and Vibrational Studies

The high-pressure behaviour of LiCrO2, a compound isostructural to the battery compound LiCoO2, has been investigated by synchrotron-based angle-dispersive X-ray powder diffraction, Raman spectroscopy, and resistance measurements up to 41, 30, and 10 Gpa, respectively. The stability of the layered structured compound on a triangular lattice with R-3m space group is confirmed in all three measurements up to the highest pressure reached. The dependence of lattice parameters and unit-cell volume with pressure has been determined from the structural refinements of X-ray diffraction patterns that are used to extract the axial compressibilities and bulk modulus by means of Birch–Murnaghan equation-of-state fits. The pressure coefficients for the two Raman-active modes, A1g and Eg, and their mode-Grüneisen parameters are reported. The electrical resistance measurements indicate that pressure has little influence in the resistivity up to 10 GPa. The obtained results for the vibrational and structural properties of LiCrO2 under pressure are in line with the published results of the similar studies on the related compounds. Research work reported in this article contributes significantly to enhance the understanding on the structural and mechanical properties of LiCrO2 and related lithium compounds.

A Review: Carbon Additives in LiMnPO4- and LiCoO2-Based Cathode Composites for Lithium Ion Batteries

Carbon plays a critical role in improving the electronic conductivity of cathodes in lithium ion batteries. Particularly, the characteristics of carbon and its composite with electrode material strongly affect battery properties, governed by electron as well as Li+ ion transport. We have reviewed here various types of carbon materials and organic carbon sources in the production of conductive composites of nano-LiMnPO4 and LiCoO2. Various processes of making these composites with carbon or organic carbon sources and their characterization have been reviewed. Finally, the type and amount of carbon and the preparation methods of composites are summarized along with their battery performances and cathode materials. Among the different processes of making a composite, ball milling provided the benefit of dense and homogeneous nanostructured composites, leading to higher tap-density and thus increasing the volumetric energy densities of cathodes.

A Tunable Molten-Salt Route for Scalable Synthesis of Ultrathin Amorphous Carbon Nanosheets as High-Performance Anode Materials for Lithium-Ion Batteries

Amorphous carbon is regarded as a promising alternative to commercial graphite as the lithium-ion battery anode due to its capability to reversibly store more lithium ions. However, the structural disorder with a large number of defects can lead to low electrical conductivity of the amorphous carbon, thus limiting its application for high power output. Herein, ultrathin amorphous carbon nanosheets were prepared from petroleum asphalt through tuning the carbonization temperature in a molten-salt medium. The amorphous nanostructure with expanded carbon interlayer spacing can provide substantial active sites for lithium storage, while the two-dimensional (2D) morphology can facilitate fast electrical conductivity. As a result, the electrodes deliver a high reversible capacity, outstanding rate capability, and superior cycling performance (579 and 396 mAh g^-1 at 2 and 5 A g^-1 after 900 cycles). Furthermore, full cells consisting of the carbon anodes coupled with LiMn₂O₄ cathodes exhibit high specific capacity (608 mAh g^-1 at 50 mA g^-1) and impressive cycling stability with slow capacity loss (0.16% per cycle at 200 mA g^-1). The present study not only paves the way for industrial-scale synthesis of advanced carbon materials for lithium-ion batteries but also deepens the fundamental understanding of the intrinsic mechanism of the molten-salt method.

A versatile single molecular precursor for the synthesis of layered oxide cathode materials for Li-ion batteries

A versatile single molecular precursor, LiTM(acac)₃, featuring a 1D chain structure, was developed to achieve the layered oxides LiTMO₂(TM = Ni/Mn/Co, NMC) for Li-ion batteries.

Reviving lithium cobalt oxide-based lithium secondary batteries-toward a higher energy density

This review summarizes the key challenges, effective modification strategies and perspectives regarding reviving lithium cobalt oxide-based lithium secondary batteries-toward a higher energy density.

An Ab Initio and Kinetic Monte Carlo Simulation Study of Lithium Ion Diffusion on Graphene

The Li⁺ diffusion coefficients in Li⁺-adsorbed graphene systems were determined by combining first-principle calculations based on density functional theory with Kinetic Monte Carlo simulations. The calculated results indicate that the interactions between Li ions have a very important influence on lithium diffusion. Based on energy barriers directly obtained from first-principle calculations for single-Li⁺ and two-Li⁺ adsorbed systems, a new equation predicting energy barriers with more than two Li ions was deduced. Furthermore, it is found that the temperature dependence of Li⁺ diffusion coefficients fits well to the Arrhenius equation, rather than meeting the equation from electrochemical impedance spectroscopy applied to estimate experimental diffusion coefficients. Moreover, the calculated results also reveal that Li⁺ concentration dependence of diffusion coefficients roughly fits to the equation from electrochemical impedance spectroscopy in a low concentration region; however, it seriously deviates from the equation in a high concentration region. So, the equation from electrochemical impedance spectroscopy technique could not be simply used to estimate the Li⁺ diffusion coefficient for all Li⁺-adsorbed graphene systems with various Li⁺ concentrations. Our work suggests that interactions between Li ions, and among Li ion and host atoms will influence the Li⁺ diffusion, which determines that the Li⁺ intercalation dependence of Li⁺ diffusion coefficient should be changed and complex.

Li1.17Mn0.50Ni0.16Co0.17O2 assembled microspheres as a high-rate and long-life cathode of Li-ion batteries

Li_1.17Mn_0.50Ni_0.16Co_0.17O₂ assembled microspheres deliver excellent electrochemical performances due to the fast Li-ion movement during the sintering process.

An in situ recovery method to prepare carbon-coated Zn–Al–hydrotalcite as the anode material for nickel–zinc secondary batteries

Carbon-coated Zn–Al–hydrotalcite (Zn–Al–LDH) is firstly synthesized by an in situ recovery method and applied as a novel anode material for Ni/Zn secondary batteries.

Development of a novel carbon-coating strategy for producing core–shell structured carbon coated LiFePO4 for an improved Li-ion battery performance

A unique process for producing core–shell structured carbon coated LiFePO₄ has successfully developed.

Enabling a High Performance of Mesoporous α-Fe2O3 Anodes by Building a Conformal Coating of Cyclized-PAN Network

The mesoporous α-Fe2O3/cyclized-polyacrylonitrile (C-PAN) composite was synthesized by a rapid and facile two-step method. The electrode was fabricated without conductive carbon addictive and employed as anode for lithium-ion batteries. Results demonstrate that building a conformal coating of a C-PAN network can provide a strong adhesion with active materials and contribute excellent electronic conductivity to the electrode, which can relieve the huge volume changes during a lithiation/delithiation process and accelerate the charge transfer rate. The material exhibited high reversible capacity of ca. 996 mAh g(-1) after 100 cycles at 0.2C, 773 mAh g(-1) at 1C and 655 mAh g(-1) at 2C, respectively, showing well-enhanced cycling performance and superior rate capacity, and also exhibiting significantly improved power density and energy density compared to the traditional graphite materials. Our results provide a facile and efficient way to enhance the performance of α-Fe2O3 anode material, which also can be applied for other oxide anode materials.

Electrode materials with tailored facets for electrochemical energy storage

In recent years, the design and morphological control of crystals with tailored facets have become hot spots in the field of electrochemical energy storage devices. For electrode materials, morphologies play important roles in their activities because their shapes determine how many facets of specific orientation are exposed and therefore available for surface reactions. This review focuses on the strategies for crystal facet control and the unusual electrochemical properties of electrode materials bound by tailored facets. Here, electrode materials with tailored facets include transition metal oxides such as SnO₂, Co₃O₄, NiO, Cu₂O, and MnO₂, elementary substances such as Si and Au, and intercalation compounds such as Li₄Ti₅O₁₂, LiCoO₂, LiMn₂O₄, LiFePO₄, and Na_0.7MnO₂ for various applications of Li-ion batteries, aqueous rechargeable lithium batteries, Na-ion batteries, Li-O₂ batteries and supercapacitors. How these electrode materials with tailored facets affect their electrochemical properties is discussed. Finally, research opportunities as well as the challenges in this emerging research frontier are highlighted.