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Lithium-ion batteries employing graphite as the anode material are now widely used in powering electronic gadgets like, mobile phones, laptops, electronic watches and calculators and also to provide required power to run engine of electric vehicles. However, storage capacity, open circuit voltage, energy density and battery life are the major considerations on which researchers are trying different alternatives to achieve better performance of the battery. In this research, Beryllium-doped and defective graphenes have been investigated by employing the ab initio DFT method. It has been found that graphene with a defect and Be–doped graphene with defects can serve as an efficient materials for anode in Li-ion batteries.

The severe capacity loss of tin-based anodes restricts their use in lithium batteries (LIBs). To enhance tin anode cycle stability, tin-antimony double-discharge anodes were designed. Additionally, by ball milling, tin-antimony oxide, and flake graphite cycling-stable composites were created. The stacked flake graphite buffers tin volume rise and enhances electrical conductivity, cyclic specific capacity, and rate performance. After 400 cycles, the tin-antimony oxide-graphite anode shows good cycling specific capacity (480mAhg${}^{-1}$). Ball milling double-discharge anode material and graphite will inspire novel carbon composite anode materials.

Yolk–shell structured Sn@C materials are promising candidates of anode materials for lithium-ion batteries due to their high structural stability along cycling. However, their synthesis usually suffers from complicated procedures, low efficiency and uncontrolled morphology and size. In this study, a novel yolk–shell structured composite of phenolic-resin-based Sn@hollow carbon (C) composite was effectively synthesized using tributyl(ethenyl)stannane as the tin source and hexadecyltrimethylammonium bromide as the structure-directing agent. Small Sn particles, with diameters of 10–20nm, were discovered to be encapsulated within hollow carbon spheres of about 100nm and exhibited high dispersion. Benefiting from this excellent structural design, the specific lithium-storage capacity of this composite can still retain a value of 640mAh g${}^{-1}$ after 150 cycles at 0.1A g${}^{-1}$. An excellent rate performance of 280mAh g${}^{-1}$ was achieved at a high current density of 1A g${}^{-1}$, without decay after 600 cycles. The present study highlights the superiority of yolk–shell structure and provides a viable option for synthesizing advanced Sn-based anode materials of lithium-ion batteries.

Silicon-based anode materials in recent years has gained tremendous interest due to high theoretical specific capacity for next generation lithium ion battery. Some biomass, such as rice husks (RHs), has contained a lot of inorganic silicon, which are abundant in all the countryside and farmland. Considering that RHs are mainly composed of organic lignin, cellulose, hemicellulose, and inorganic Si compound, they could be used to prepare low-cost electrode materials, such as carbonaceous and silicon-based anode materials. In this work, we will present the synthesis of various anode materials from RHs with prominent performance for lithium ion battery application, such as porous C/SiO${}_x$ composites and Al-doped porous carbonized RHs husks composites.

The chemical plating methods were used to prepare nanoshell Si/Cu composites. The methods delivered a high initial discharge and charge capacity of 1312.1 and 1008.8 mAh/g, respectively. The electrochemical properties of the composites retained about 662.6 mAh/g after 100 cycles. The Cu coating improved the electrical conductivity but hindered the direct contact of the Si particles and the electrolyte, which suppressed the SEI growth.

The present work emphasizes on the synthesis of Ni (10, 20 and 30 mol%) added tetragonal (t) ZrO₂ nanopowders and Ni/NiO:t-ZrO₂ (50:50 mol%) nanocomposites through precipitation route using hydrazine hydrate (N₂H₅OH) as a precipitating reagent. In this work, the precipitation route is optimized using different ways. Phase development, particle morphology and phase distributions were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM) and back scattered mode-scanning electron microscopy (SEM), respectively. Structural analysis revealed that the constant pH way is effective in synthesizing Ni:t-ZrO₂ nanopowders up to moderate temperatures as compared to direct or reverse way. The minimum concentrations of Ni for stabilization of t-ZrO₂ (due to incorporation of Ni²⁺ in the ZrO₂ lattice) at 700°C and 800°C are 10 mol% and 20 mol%, respectively. Uniform distribution of Ni/NiO phases in ZrO₂ matrix with 35–42% porosity was observed in 50 mol% Ni added t-ZrO₂ nanocomposite pellets, calcined in air and H₂ atmosphere. The precipitation method using N₂H₅OH for preparing Ni/NiO:t-ZrO₂ nanocomposite powders, is attractive and could be useful in synthesizing anode material for intermediate temperature solid oxide fuel cell application.

Highly ordered mesoporous antimony-doped tin oxide (ATO) materials, containing different amount of antimony in the range of 0–50mol%, are prepared via a nanoreplication method using a mesoporous silica template. The mesoporous ATO materials thus obtained exhibit high electrical conductivity, high reversible capacity, superior cycle stability and good rate capability as anode materials for lithium-ion batteries, compared to those of pure mesoporous tin oxide. Amongst the ATO materials in this work, the mesoporous ATO material with 10mol% of antimony has highest discharge capacity of 1940mAhg^-1 (charge capacity of 1049) at the 1st cycle, best cycle performance (716mAhg^-1 at 100th cycle) and excellent rate capability, which are probably due to the enhanced electrical conductivity as well as reduced crystalline size.

Li₄Ti₅O₁₂–rutile TiO₂ (LTO–RTO) dual-phase nanocomposite anode materials show excellent electrochemical performance. However, the effects of molar ratio of Li/Ti and thermal treatment on electrochemical properties of the LTO–RTO composite have been rarely reported. In this work, LTO–RTO nanocomposites were prepared by sol-hydrothermal method with different Li/Ti molar ratios in raw materials and following calcinations at 600${}^{\circ }$C, 650${}^{\circ }$C and 700${}^{\circ }$C for the different holding time. The results indicate that with the decrease of Li/Ti molar ratio, the discharge capacity of the LTO–RTO nanocomposite increases at first and then decreases, and the optimal Li/Ti molar ratio is 4:4.77, which was obtained with calcination at 600${}^{\circ }$C for 10h. The effects of calcination temperature and holding time were further investigated. The result demonstrates that the thermal treatment has an obvious influence on the electrochemical performance due to the morphology change in the nanocomposite. The LTO–RTO nanocomposite calcinated at 650${}^{\circ }$C for 2h with a Li/Ti molar ratio of 4:4.77 in raw materials delivers excellent rate capability: the initial discharge capacity is 175.9, 176.3, 170.4, 167.5, 163.3 and 155.6mA h g${}^{-1}$ at the rate of 0.5, 1, 3, 5, 10 and 20${}^{\circ }$C (1 C$=$175 mA h g${}^{-1}$), respectively.

Co₃O₄ nanocrystals have been synthesized via an ordinary one-step calcination of a cobalt-based 2D coordination polymer [Co(tfbdc)(4,4${}^{\prime }$-bpy)(H₂O)₂]. As an anode material for lithium-ion batteries, the obtained Co₃O₄ nanocrystals exhibit high reversible capacity, excellent cyclic stability and better rate capability. The reversible capacity of the Co₃O₄ nanocrystals maintains 713mAhg${}^{-1}$ after 50 cycles at a current density of 50mAg${}^{-1}$. Our results confirm that searching for metal oxides nanomaterials used as anode materials of lithium ion batteries via the calcinations of 2D coordination polymer is a new route.

For lithium-ion batteries (LIBs) with high energy density, it is critical to develop reliable and high-capacity anode materials. In this work, d-Ti₃C₂T_x/h-BN hybrid layered nanocomposites with uniform distribution are synthesized using a simple liquid phase blending method and investigated as an anode material for LIBs. The results reveal that the uniformly dispersed h-BN anchored on the d-Ti₃C₂T_x nanosheets can effectively prevent the d-Ti₃C₂T_x nanosheets from restacking during charging and discharging processes, as well as improve the electronic conductivity. The studies show that the electrochemical performance, such as the capacity and cyclic stability, of d-Ti₃C₂T_x/h-BN electrode is better than that of pure d-Ti₃C₂T_x materials.

Three main iron oxides, FeO, Fe₂O₃, and Fe₃O₄, have attracted much attention as anode materials for lithium-ion batteries (LIBs) for their high theoretical capacity, low cost, large-scale reserves, and environmental benignity. However, the poor cycling life and rate capability limit their commercial application on a large scale. Glaring strategies have been adopted to improve the performance of lithium storage. In this review, the electrochemical performances of FeO, Fe₂O₃, and Fe₃O₄ anode materials could be improved by the decrease in particle size, regulation and control of the nanomicrostructures, the improvement of electrical conductivity, and the design of composites. Their effects on the electrochemical performance of the anode materials are discussed in detail. Furthermore, the development prospect of iron oxide-basedanode material has been prospected.

The microstructure and electrochemical property of Cu–Al–Si alloy anode material are studied in this paper. The research shows that the alloy particle has a basic circular outline, and two copper-rich phases with different silicon contents are detected in the particle, and both phases with nanostructure are observed in its surface layer. The nano-silicon alloy negative electrode material needs to be used in a certain proportion with graphite, binder and conductive agent, and the stirring process also has an important influence on its electrochemical performance. Multiple mixing can achieve a better cycle retention compared to direct mixing. The first-cycle coulombic efficiency of the electrode material is improved up to about 90%, and the specific capacity is still higher than 500mAhg${}^{-1}$ after 100 cycles. The battery manufacturing process is similar to the graphite negative electrode, so it is easy to be applied.

Li₃VO₄ has gained significant attention as a promising anode material for lithium-ion batteries owing to its high specific capacity, low cost and safe working potential. Unfortunately, its disappointing electronic conductivity limits its rate performance. To address this problem, a series of Cr${}^{3+}$-doped Li₃VO₄ compounds are synthesized by solid-state reaction. The obtained Li${}_{3-x}$Cr${}_{2x}$V${}_{1-x}$O₄ compounds ($x=0,0.01$ and 0.02) have the same orthorhombic crystal structure (Pnm2₁ space group), suggesting the successful Cr${}^{3+}$ doping in Li₃VO₄. Compared with Li₃VO₄, Li${}_{2.98}$Cr${}_{0.04}$V${}_{0.98}$O₄ exhibits a two orders of magnitude larger electronic conductivity. Additional benefits of the Cr${}^{3+}$ doping include the increase of the Li${}^{+}$ diffusion coefficient and the decrease of the particle size. Consequently, Li${}_{2.98}$Cr${}_{0.04}$V${}_{0.98}$O₄ displays not only a large reversible capacity (363mAh g${}^{-1}$ at 60mA g${}^{-1})$ and superior cyclic stability (86.6% capacity retention after 1000 cycles at 1200mA g${}^{-1})$ but also decent rate performance (147mAh g${}^{-1}$ at 1200mA g${}^{-1})$.

Despite its high theoretical specific capacity, direct application of SiO${}_x$ is challenging particularly in terms of alleviating volume effect and improving electronic conductivity to enhance the battery performance. SiO${}_x$/CNTs/Sn composite with high cyclability and rate performance was proposed by a modified Stöber liquid phase method, CNTs and metallic tin were employed during the subsequent mechanical ball milling process to investigate their effects on the resulting physicochemical property and electrochemical performance. The structure of /CNTs/Sn composite was designed, and the multi-structure not only alleviates the volume effect of SiO${}_x$ to a certain extent but also provides additional diffusion pathways for lithium ions, electrons, and flexible substrate. From electrochemical characterization, the half-cell battery integrating SiO${}_x$/CNTs/Sn anode exhibits a capacity of 880.83 mAh g${}^{-1}$ with 6.3% capacity fading after 100 cycles at 0.1 A g${}^{-1}$ and excellent rate performance. The simple and ingenious synthesis method could provide new development and application ideas for SiO${}_x$-based anode materials.

To improve lithium storage performances of tin-based oxide electrodes, i.e. SnO₂ microspheres reinforced by Al₂O₃ and CNTs (SnO₂-Al₂O₃/CNT) are constructed using a convenient microwave-assisted method. The findings indicate that the SnO₂-Al₂O₃/CNT composite predominantly consisted of the rutile structure phase, with a minor presence of the orthorhombic phase. SnO₂-Al₂O₃/CNT electrodes demonstrate greater capacity, significantly enhanced cyclability and improved rate performance when compared to the electrodes based on SnO₂-Al₂O₃ and SnO₂. Specifically, a sable specific capacity of 745.34 mAh/g can be maintained at 1.0 A/g, while a large specific capacity of 617.36 mAh/g can still be demonstrated at a high current density of 4.0 A/g after 100 cycles. The improved Li-storage performances may be attributed to by the significant synergistic effect among SnO₂, Al₂O₃, CNTs, and the morphology as well.

MXene is one kind of a promising anode material due to its graphene-like structure, excellent electrochemical characteristics and low lithium ion diffusion barrier. But the lower specific capacity couldn’t meet the demands in practical application. Here, we have constructed coconut-derived carbon anchored within the MXene layers, which improves the conductivity to prompt the kinetics upon redox reactions, in the meantime, shorts the transfer distance and buffers volume changes, synergistically improving the electrochemical reversibility during charge and discharge processes. Naturally, the MXene/C hybrid anode delivers a high initial discharge specific capacity of 1951.7 mAh g${}^{-1}$ at 0.1 A g${}^{-1}$. Additionally, it maintains a stable cycle with a reversible capacity of 511.7 mAh g${}^{-1}$ after 500 cycles at 0.5 A g${}^{-1}$. This work paves a straightforward avenue to developing a versatile MXene-based anode for high performance LIBs.

In this paper, SnO₂ nanospheres have been synthesized via a surfactant-free solvothermal reaction followed by a heat treatment. CV results demonstrate that the formation of Li₂O is partially reversible. Moreover, electrochemical measurements indicate the preferable electrochemical properties of SnO₂ nanospheres.

In this paper, we report an interesting approach for efficient synthesis of uniform sub-micrometer carbon supported Fe₃O₄ hollow spheres. Fe₃O₄ precursor was first coated on the surface of sulfonated polystyrene hollow microspheres. Then, the precursor and sulfonated polystyrene hollow microspheres were converted into Fe₃O₄ and carbon hollow spheres when heated at 550°C in N₂ atmosphere. The obtained Fe₃O₄ @ carbon hollow microspheres exhibit enhanced lithium storage properties compared with Fe₂O₃ hollow spheres as anode materials, delivering a reversible capacity of 612 mA hg⁻¹ after 50 cycles at a high current density of 400 mA g⁻¹.

This paper is concerning to prepare modified natural graphite which is low-cost and advanced materials used as lithium ion battery anode using the way of cladding natural graphite with epoxy resin. The results shows that the specific capacity and circular performance of the modified natural graphite, which is prepared in the range of 600°C and 1000°C, have been apparently improved compare with the not-modified natural graphite. The first reversible capacity of the modified natural graphite is 338mAh/g and maintain more than 330mAh/g after 20 charge/discharge circles.

The anode materials Li₄Ti₅O₁₂ was successfully prepared through solid-state reaction using Li₂CO₃ and TiO₂. The phase purity and microstructure of the synthesized powders were studied by X-ray diffraction, scanning electron microscopy (SEM). The particles are well dispersed with diameters distributed in the range of 200–250 nm. Li₄Ti₅O₁₂ was doped with different mole fractions of Mg\Zr to improve the electrochemical performance of the sample at a high current rate. The better charge and discharge capacities, 123mAh/g and 130mAh/g, were obtained when the current density was 1C. The rate performance of Li₄Ti₅O₁₂ could also be enhanced by doping Mg\Zr.