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Abstract: LiFePO4, doped LiM x Fe1−x PO4, and Li1−x M x FePO4 compounds have been prepared via a sol–gel synthesis method. The physical properties of the as-prepared lithium iron phosphates were characterised by X-ray diffraction, X-ray absorption near-edge spectroscopy (XANES), and magnetic susceptibility. The electrochemical properties lithium iron phosphates were tested by a variety of electrochemical techniques. Lithium iron phosphate electrodes demonstrated a stable discharge capacity of 160–165mAhg−1, almost approaching the theoretical capacity. The good electronic conductivity and nanocrystalline could contribute to the unique performance of lithium iron phosphate electrodes. Lithium iron phosphates have a significant potential to be used as a new cathode materials in Li-ion batteries. [Copyright &y& Elsevier]

Abstract: A series of polypyrrole-LiFePO4 (PPy-LiFePO4) composites were synthesised by polymerising pyrrole monomers on the surface of LiFePO4 particles. AC impedance measurements show that the coating of polypyrrole significantly decreases the charge-transfer resistance of LiFePO4 electrodes. The electrochemical reactivity of polypyrrole and PPy-LiFePO4 composites for lithium insertion and extraction was examined by charge/discharge testing. The PPy-LiFePO4 composite electrodes demonstrated an increased reversible capacity and better cyclability, compared to the bare LiFePO4 electrode. [Copyright &y& Elsevier]

Abstract: Carbon coated lithium iron phosphates were prepared by a carbon aerogel synthesis process, through which LiFePO4 particles were embedded in amorphous carbon. The carbon coating effect can significantly enhance the electronic conductivity of LiFePO4. The electrochemical properties of the as-prepared LiFePO4 cathode materials were systematically characterised. The carbon coated LiFePO4 cathode demonstrated a high capacity and stable cyclability. [Copyright &y& Elsevier]

Abstract: Stoichiometric and non-stoichiometric Mg-doped lithium iron phosphates were synthesised via spray-pyrolysis, followed by sintering at high temperature for crystallization. The spray pyrolysis process allows the homogeneous mixing of the ingredient reactants at atomic level. The electronic conductivities of the Mg-doped lithium iron phosphates have been drastically improved by 4 orders of magnitude, comparing to the undoped LiFePO4. The electrochemical properties of as-prepared lithium iron phosphates were systematically measured by cyclic voltammetry and constant current charge/discharge cycling tests. [Copyright &y& Elsevier]

Nanostructured Si–C composite materials were prepared by dispersing nanocrystalline Si in carbon aerogel and subsequent carbonization. Through this process, nanosize Si was homogeneously distributed in a carbon matrix. The Si–C composites exhibit a reversible lithium storage capacity of 1450 mA h/g when used as anodes in lithium-ion cells. The nanostructured Si–C composite electrodes demonstrated good cyclability. The Si–C composites could provide a novel anode material for lithium-ion batteries. [Copyright &y& Elsevier]

The synthesis and electrochemical characteristics of LiCoxMnyNi1−x−yO2 as cathode materials for rechargeable lithium-ion batteries were investigated. The precursor CoxMnyNi1−x−y(OH)2 was obtained by the chemical co-precipitation method. LiCoxMnyNi1−x−yO2 (0≤x≤0.3, and y=0.2) was prepared by heating a mixture of CoxMnyNi1−x−y(OH)2 and Li2CO3 at 850–900 °C for 24 h in air. The X-ray diffraction (XRD) patterns indicated that pure phase LiCoxMnyNi1−x−yO2 was obtained. The scanning electron micrographs (SEMs) show that the synthesized LiCoxMnyNi1−x−yO2 compounds have good micro-morphology and uniform particle size. The electrochemical properties of these materials such as the galvanostatic charge–discharge performance and cyclic voltammetry were systematically measured. [Copyright &y& Elsevier]

Tin, tin oxide and NiSn-based nanocomposites with Al2O3 dispersion were prepared by ball milling to see their electrochemical properties as a new anode material for lithium-ion batteries. Electrochemical tests demonstrated that the initial charge–discharge capacities are very high for these materials. However, the capacity faded rapidly after the first cycle due to irreversible reactions. This is thought to be caused by the separation of the active materials from the inert oxide particles. The initial cycling efficiency was markedly improved by subsequent annealing of the ball-milled electrode. [Copyright &y& Elsevier]