Nanoparticles of SnO were synthesized sonochemically in mildly basic SnCl2 solutions. The amorphous product thus obtained could be transformed to a nanocrystalline phase by heating to 200 °C. Composite electrodes comprised (by weight) of 80% SnO, 10% graphite flakes (conductive additive), and 10% polymeric binder (an optimal composition) were tested as anodes for rechargeable Li batteries. The nanocrystalline SnO was found to be much more effective as an active material for electrodes than the initial amorphous phase. These electrodes could reach nearly their theoretical capacity (≃790 mAh/g, SnO) in electrochemical lithiation−delithiation processes versus a Li counter electrode in nonaqueous Li salt solutions. However, there is still a long way to go to the possible use of SnO as an anode material in practical batteries. This is due to its high irreversible capacity (Li2O formation and surface film precipitation due to reactions of lithium−tin compounds with solution species) and gradual capacity decrease during repeated charge−discharge cycling. Possible reasons for this capacity fading are discussed. The tools for this study included electron microscopy (both TEM and SEM), thermal analysis (DSC), XRD, FTIR and impedance spectroscopies, and standard electrochemical techniques.

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Carbon powders were prepared by milling graphite particles in different atmospheres including air, highly pure argon, nitrogen, and CO 2 . Part of the samples was further exposed to air after milling. The carbonaceous materials thus obtained were tested as Li-insertion anodes in nonaqueous Li salt solutions. It was found that the atmosphere in which the active mass was prepared had a pronounced impact on the specific surface area of the particles obtained, probably due to the effect of surface groups on the carbons developed in the milling process. It was also found that the atmosphere to which the powders were exposed had a remarkable impact on the electrochemical behavior of the carbon electrodes in Li-insertion processes. The milling of the graphite produces highly reactive carbon surface sites, which react readily with active gases such as oxygen and CO 2 . The surface groups thus formed influence the surface chemistry developed on these electrodes in solutions. Since the electrochemical behavior of Li-C insertion electrodes depends strongly on the nature of the passivation films developed on these electrodes at low potentials, the milling atmosphere strongly influences their electrochemical behavior. The electrochemical processes were studied by chronopotentiometry, cyclic voltammetry, and impedance spectroscopy, the electrodes' structure and morphology were explored by X-ray diffraction and scanning electron microscopy, and the carbons' surface chemistry was studied by Fourier transform infrared and X-ray photoelectron spectroscopy.

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