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Spinel LiMn 2 O 4 and LiM 0.02 Mn 1.98 O 4 (where M is Zn, Co, Ni and In) were produced via facile sol–gel method and Cu/LiMn 2 O 4 , Cu/LiM 0.02 Mn 1.98 O 4 , Ag/LiMn 2 O 4 and Ag/LiM 0.02 Mn 1.98 O 4 binary composite electrode materials were produced via electroless coating techniques as a positive electrode material for Li-ion batteries. The phase composition, morphology and electrochemical properties of the synthesized materials were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), cyclic voltammometry (CV), galvanostatic charge–discharge tests and electrochemical impedance spectroscopy (EIS). The synthesized cathode active materials are characterized as single phase spinel LiMn 2 O 4 with degree of crystallization and uniform particle size distribution. Best results were obtained with electrodes substituted with In and an initial discharge capacity of 134 mAhg −1 after 50 cycles. The improvement in the cycling performance may be attributed to stabilization of spinel structure by smaller lattice constant when manganese ion was partially substituted with In 3+ ions. EIS analysis also confirms that the obvious improvement in Ag coating is mainly attributed to the accelerated phase transformation from layered phase to spinel phase and highly stable electrolyte/electrode interface due to the suppression of electrolyte decomposition. [ABSTRACT FROM AUTHOR]

Sn–Co alloy films for Li-ion batteries were prepared by pulse electrodeposition on the copper foils as current collectors. Nanocrystalline Sn–Co alloy electrodes produced by using a solution containing cobalt chloride and tin chloride at constant electrodeposition conditions (pulse on-time t on at 5 ms and pulse off-time t off at 5 ms) with varying peak current densities, Jp have been investigated. The structures of the electroplated Sn–Co alloy thin films were studied to reveal film morphology current density relationships and the effect of the current density parameters on the electrochemical properties. X-Ray Diffractometer (XRD), Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area analyzer and Energy-Dispersive X-ray Spectroscopy (EDS) facilities were used for determination the relationships between structure and experimental parameters. Cyclic voltammetry (CV) tests were carried out to reveal reversible reactions between cobalt–tin and lithium. Galvanostatic charge/discharge (GC) measurements were performed in the cells formed by using anode composite materials produced by pulse electro co-deposition. The discharge capacities of these cells were cyclically tested by a battery tester at a constant current in the different voltage ranges between 0.02 V–1.5 V. The results have shown that Sn–Co alloy yielded promising reversible discharge capacities with a satisfactory cycle life for an alternative anode material to apply for the Li-ion batteries. [ABSTRACT FROM AUTHOR]