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Highlights • A new hexagonal prisms CoO was assembled on reduced graphene oxide. • CoO in the composite is pure purity. • The composite performed high capacity as anode materials of lithium ion batteries. Abstract In this research, we use a modified sol-gel method to obtain a pure phase new hexagonal CoO on reduced graphene oxide by leading of polar solvent. In the electrochemical test, the CoO/rGO composite shows a remarkable performance of capacity as an anode of a lithium ion battery. The electrochemistry performance shows that the capacity of the composite can remain at 1300 mAh/g in 100 cycles without damping. The pure phase of CoO and its hexagonal morphology have been characterized by XRD, SEM and TEM. [ABSTRACT FROM AUTHOR]

A low-cost and scalable ultrasonic synthetic method to produce copper metal current collector with uniform nanopores on the surface is achieved for the first time. A layer of silicon active material was sputtered on the surface of as-prepared metal current collector (vs. metal lithium) as an innovative current collecting material for lithium ion battery. The assembled battery with this current collector showed an areal capacity of 2.2 mAh/cm 2 , comparable to that of commercially available lithium ion batteries. Due to the nano-porous structure of current collector, the silicon active material electrochemical capacity retention and cycling stability also improved significantly. [ABSTRACT FROM AUTHOR]

To improve the electrochemical performance of silicon-based anode material, the silicon/carbonized polydopamine/graphene (Si/PDAC/rGo) was prepared via pre-coating process in which graphene oxide was added and subsequent annealing process. The silicon particles with polydopamine (PDA) layer was encapsulated by graphene sheets due to interaction between the amine groups on PDA and the oxygen-containing groups on graphene oxide (GO), so the aggregation of silicon particles was hindered. The X-ray photoelectron spectroscopy (XPS) results present that most of the oxygen-containing groups were removed and the carbon layer contained nitrogen element. The initial coulombic efficiencies of Si/PDAC/rGo were 83.8%, 84.3%, 83.1% at 0.1, 0.3, 0.5 A g −1 , respectively. The cycle and rate performance of Si/PDAC/rGo was also enhanced ascribed to the synergistic buffer effects of carbonized polydopamine layer and graphene sheets. [ABSTRACT FROM AUTHOR]

In this study, we report a facile and novel method for preparing the porous Sb 2 S 3 /Sb composite. When the as-synthesized electrode is applied as an anode for lithium ion battery, it exhibits good cycling stability and rate capability. The capacity of the Sb 2 S 3 /Sb composite at a current density of 1.0 A g −1 for the 200th cycle is 387 mAh g −1 . Even when the current density is 10 A g −1 , the electrode still keeps a capacity of 250 mAh g −1 . To the best of our knowledge, the attractive electrochemical properties are much more distinguished than the Sb 2 S 3 -based anodes for li-ion batteries published to date. In addition, the simple synthesis method is applicable to the fabrication of a variety of chalcogenide electrode materials for batteries. [ABSTRACT FROM AUTHOR]

A novel facile strategy was developed to prepare the Fe 3 O 4 @graphene aerogel (Fe 3 O 4 @GA) composites. Fe 3 O 4 nanoparticles were uniformly dispersed into the 3D network of graphene aerogel and the resultant hybrid composites contained meso- and macro-scale pores with high specific surface area (276.9 m 2 g −1 ) and large pore volume (0.3230 cm 3 g –1 ). The electrochemical performance revealed that the Fe 3 O 4 @GA anode exhibited high reversible capacity (~941.5 mAh g −1 at a current density of 100 mA g −1 ), stable cycling performance, and excellent rate capability. [ABSTRACT FROM AUTHOR]

The Li4Ti5O12/G/CNTs hybrid material was synthesized via a facile rheological phase reaction route. For comparison, the Li4Ti5O12/G hybrid material was also prepared using the similar rheological phase method. The results showed that the Li4Ti5O12/G/CNTs had better rate capability and cycling performance than that of the Li4Ti5O12/G. At 0.2 C, the initial discharge capacity of the Li4Ti5O12/G/CNTs was 172 mA h/g, and even at the high rate of 5.0 C and 10.0 C, it could still remain at 150 mA h/g and 144 mA h/g, respectively. Moreover, only less than 6% discharge capacity loss over 100 cycles at 10.0 C was observed. The outstanding electrochemical performances make it a promising anode material for high rate lithium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Zn2V2O7 nanorods were successfully synthesized by a hydrothermal route for the application in the Lithium ion batteries. The effects of the reacting time on the Zn2V2O7 nanorods as well as the corresponding electrochemical properties were investigated. Results show that the obtained sample under the optimum condition possesses high crystallinity; the width and the thickness are in the range of 40–60nm and 20–40nm, respectively. Based on the observations, a possible growth mechanism of Zn2V2O7 nanorods could be described as a reacting–exfoliating–splitting process. Besides, the Zn2V2O7 nanorods used as anode materials in rechargeable lithium-ion battery can exhibit a highly reversible discharge/charge capacity and excellent rate property at a current density as high as 0.1Ag−1. This might be attributed to the intrinsic characteristics of the layered structure of Zn2V2O7 nanorods. [Copyright &y& Elsevier]

Abstract: Li2MnSiO4 cathode materials doped with various cationic ions, Ga3+, Al3+, and Mg2+, are synthesized and their microstructure and electrochemical properties are investigated. The samples doped with trivalent ions, especially Ga3+, lead to a higher charge/discharge capacity and initial efficiency with well-dispersed nanoparticle formation. We can realize that the enhanced electrochemical performance of the specific ion doped Li2MnSiO4 cathodes originated from the uniformly distributed nanoparticles rather than the additional lithium insertion/extraction of the given cathode materials induced by the charge compensation. [Copyright &y& Elsevier]

Abstract: Li4Ti5O12 and Ru-doped Li4Ti5O12 with the formulation of Li4Ti4.99Ru0.01O12 were prepared by a modified solid-state method. The structure and electrochemical properties of the as-prepared powders were systematically investigated. Li4Ti4.99Ru0.01O12 exhibited an excellent rate capability with a discharge capacity of 146mAhg−1 at 1C, 126mAhg−1 at 5C, 119mAhg−1 at 10C and even 107mAhg−1 at 20C. Electrochemical impedance spectra (EIS) reveal that the Li4Ti4.99Ru0.01O12 exhibited the improved electronic conductivity and higher lithium-ion diffusivity than that of Li4Ti5O12. The novel Li4Ti4.99Ru0.01O12 material stands as a promising potentially high rate anode material for the lithium ion batteries. [Copyright &y& Elsevier]

Abstract: SnO2/graphene nanocomposite was prepared via an in situ chemical synthesis method. The nanocomposite was characterized by X-ray diffraction, filed emission scanning electron microscope and transmission electron microscope, which revealed that tiny SnO2 nanoparticles could be homogeneously distributed on the graphene matrix. The electrochemical performance of the SnO2/graphene nanocomposite as anode material was measured by galvanostatic charge/discharge cycling. The SnO2/graphene nanocomposite showed a reversible capacity of 665mAh/g after 50cycles and an excellent cycling performance for lithium ion battery, which was ascribed to the three-dimensional architecture of SnO2/graphene nanocomposite. These results suggest that SnO2/graphene nanocomposite would be a promising anode material for lithium ion battery. [ABSTRACT FROM AUTHOR]

Layered cathode materials with the nominal compositions of 0.6LiNi0.5Mn0.5O2·xLi2MnO3·yLiCoO2 (x+y=0.4) were synthesized by conventional solid-state reaction. Their XRD patterns indicated the formation of solid solutions. The content of Li2MnO3 in the solid solutions presented important effects on structure and electrochemistry. The end member, 0.6LiNi0.5Mn0.5O2·0.4LiCoO2, was isostructural to LiCoO2, but increasing Li2MnO3 content in solid solution materials brought about partial cation ordering. Electrochemical results demonstrated that the increasing of Li2MnO3 content in materials improved cycleability. The samples with 0.2≤x≤0.4 delivered the initial discharge capacity of around 190 mA h/g with good cycling performance and are the promising cathode materials in view of capacity and cycleability. [Copyright &y& Elsevier]