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Abstract: A series of Li x CoPO4 (x =0.90, 0.95, 1, 1.05) compounds with different lithium content in the starting compositions were prepared by the sol–gel method. The phase identification was carried out by X-ray diffraction and neutron diffraction. The structure, atom positions, and occupancies were characterized by neutron diffraction. The morphology of Li x CoPO4 (x =0.90, 0.95, 1, 1.05) was examined by field emission scanning electron microscopy. Electrochemical analysis indicated that Li0.95CoPO4 presented the highest discharge capacity at various current densities among all the different x value compounds. The Li0.95CoPO4 showed better cycling stability and coulombic efficiency in the room temperature ionic liquid electrolyte ([C3mpyr][NTf2] containing 1M LiNTf2) at various current densities in the voltage range of 3.5–5.0V than in the conventional electrolyte (1M LiPF6 in ethylene carbonate:diethyl carbonate). [Copyright &y& Elsevier]

Abstract: Carbon-coated SnO2 nanoparticles were prepared by a novel facile route using commercial SnO2 nanoparticles treated with concentrated sulfuric acid in the presence of sucrose at room temperature and ambient pressure. The key features of this method are the simple procedure, low energy consumption, and inexpensive and non-toxic source materials. As-prepared core/shell nanoparticles were characterized by X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The electrochemical measurements showed that the carbon-coated SnO2 nanoparticles with 10% carbon and using carboxymethyl cellulose (CMC) as a binder displayed the best electrochemical performance with the highest specific capacity of 502mAhg−1 after 50 cycles at a current density of 100mAg−1. In addition, owing to the water solvability of CMC, the usage of CMC as binder makes the whole electrode fabrication process cheaper and more environmental friendly. [Copyright &y& Elsevier]

Highlights: [•] A model of TiO2 nanotube arrays growing on Ti mesh was proposed. [•] The TiO2/Ti mesh was used for the anode without current collector or binder required. [•] The capacity of the TiO2/Ti-600min mesh electrode is 1745.5μAhcm−2 over 100 cycles. [•] The TiO2/Ti mesh electrode still maintains its 3D nanostructure after 100 cycles. [Copyright &y& Elsevier]

Abstract: A conducting α-LiFeO2-polypyrrole (α-LiFeO2-PPy) nanocomposite material was prepared by the chemical polymerization method as a cathode material for lithium-ion batteries. The porous α-LiFeO2 was prepared via the microwave hydrothermal method and a post-annealing. The X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy measurements showed that the α-LiFeO2 nanoparticles were coated with PPy. The polypyrrole coating improves the reversible capacity and cycling stability (104mAhg−1 at 0.1C after 100 cycles) for lithium-ion batteries. Even at the high rate of 10C, the electrode showed more than 40% of the capacity at low rate (0.1C). [Copyright &y& Elsevier]

In this study, LiNi0.5Mn1.5O4 (LNMO) nanoparticles were prepared as a 5V cathode material via a rheological phase method and annealed at different temperatures: 680°C, 750°C, and 820°C. The sample annealed at 750°C shows the best performance. A room temperature ionic liquid (RTIL) containing 1M lithium bis(trifluoromethanesulfonyl) imide (LiNTf2) in N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl) imide (C4mpyrNTf2) was used as novel electrolyte in conjunction with the LNMO cathodes and their electrochemical properties have been investigated. The results show that the LNMO using RTIL as electrolyte has better coulombic efficiency and comparable discharge capacities to those of the cells assembled with standard liquid electrolyte (1M LiPF6 in ethylene carbonate/diethyl carbonate). Electrochemical impedance spectroscopy shows that the RTIL is much more stable as the electrolyte for LiNi0.5Mn1.5O4 than the conventional electrolyte. [ABSTRACT FROM AUTHOR]

Abstract: SnO2-coated multiwall carbon nanotube (MWCNT) nanocomposites were synthesized by a facile hydrothermal method. The as-prepared nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The SnO2/MWCNT composites, when combined with carboxymethyl cellulose (CMC) as a binder, show excellent cyclic retention, with the high specific capacity of 473mAhg−1 beyond 100 cycles, much greater than that of the bare SnO2 which was also prepared by the hydrothermal method in the absence of MWCNTs. The enhanced capacity retention could be mainly attributed to good dispersion of the tin dioxide particles in the matrix of MWCNTs, which protected the particles from agglomeration during the cycling process. Furthermore, the usage of CMC as a binder is responsible for the low cost and environmental friendliness of the whole electrode fabrication process. [Copyright &y& Elsevier]