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Abstract: Nanosized pure SnSb and SnSb with excess ductile Sn (referred to as Sn/SnSb) powders have been synthesised by careful reductive co-precipitation in NaBH4. Crystallite sizes for both powders measure in the 50–100nm range with particles agglomerating up to a few micrometers in pure SnSb powder and several tens of micrometers in the Sn/SnSb composite. Pristine powders were mixed separately with carbon black in order to improve dispersion and electronic conduction. Electrodes were constructed using the powders and tested as Li-ion half cell in order to measure the electrochemical performance. The energy storage capacity of electrodes improved in excess of 50% by increasing quantity of carbon black from 20wt.% to 50wt.%. Capacity fade over repeated charge and discharge cycles still remains a challenge to practical application of SnSb and Sn/SnSb alloy electrodes. [Copyright &y& Elsevier]

Orthorhombic LiMnO2 with small grain size was successfully synthesised using a one-step middle-temperature solid-state reaction (OSSS). Compared with the methods other researchers used, the OSSS method is much simpler. It is a one-step method without intermediate regrinding or other treatments. The o-LiMnO2 obtained showed a high initial capacity 180 mAh/g when cycled at a current density of 0.5 mA/cm2 at room temperature, and the rate capability was improved due to the smaller particle size. Therefore, the one-step middle temperature solid-state reaction could be a promising method for o-LiMnO2 compound synthesis. [Copyright &y& Elsevier]

Nanosize cobalt oxides (Co3O4) were synthesised by chemical decomposition of cobalt octacarbonyl in toluene at low temperature. Electrochemical properties of as-prepared Co3O4 as anodes in Li-ion cells were tested. The nanosized Co3O4 electrode demonstrate a stable reversible lithium storage capacity of 360 mAh/g within 30 cycles. The reactivity of as-prepared Co3O4 in Li-ion cells could be attributed to nanosize particles of Co3O4 and its lithiation products. [Copyright &y& Elsevier]

A series of compounds LiMn0.7M0.3O2 (M=Ti, V, Zn, Mg, Mo, Co, Cr) with different doping elements were synthesized. It was found that the ionic size of the doping elements is not a discriminating factor in the structure of LiMn0.7M0.3O2 compounds. The LiMn0.7M0.3O2 (M=Cr, Zn, Mg, V) forms in the hexagonal structure, while the LiMn0.7M0.3O2 (M=Co, Ti, Mo) shows an orthorhombic structure. The LiMn0.7M0.3O2 compounds have less crystal distortion compared with o(orthorhombic)-LiMnO2. All substituted materials cycled between 4.4 and 2 V in Li cells show higher stability of capacity compared with the standard o-LiMnO2. AC impedance analysis results show that the charge transfer process and lithium ion diffusion process for doped LiMnO2 compounds are better than that for un-substituted compounds. [Copyright &y& Elsevier]

Abstract: A series of LiMn x Fe1−x PO4 (x =0, 0.1, 0.3, 0.5, 0.7, 0.9, 1) compounds were synthesised by a sol–gel preparation route. X-ray diffraction and Rietveld structure refinement revealed that the lattice parameters (a, b and c) of orthorhombic LiMn x Fe1−x PO4 increase with increasing Mn content. Magnetic susceptibility measurements show antiferromagnetic behaviour for LiMn x Fe1−x PO4 samples. The electrochemical properties of LiMn x Fe1−x PO4 as cathodes in lithium-ion cells were tested via cyclic voltammetry and galvanostatic charge/discharge measurements. The electrochemical performance of LiMn x Fe1−x PO4 degrades with increasing Mn content. [Copyright &y& Elsevier]