Li-Mn-O thin films were deposited by pulsed laser deposition (PLD) onto stainless steel substrates using targets containing different concentrations of added Li 2 O. The influence of the target composition on the stoichiometry of the resulting thin films, the surface morphology and the electrochemical properties was studied. The application of the target with added 7.5 mol% Li 2 O results in an almost ideal lithium content, while all films were still oxygen deficient. The thin films were applied as electrodes in Li//Li 1+x Mn 2 O 4−δ cells (i.e. model cells for a rechargeable Li-ion battery) and characterized by cyclic voltammetry and galvanostatic charge/discharge experiments. The electrochemical measurements of the thin films confirmed that the thin films can serve as good model systems and that they show a sufficient cyclability.

The formation of a solid electrolyte interphase (SEI)-type layer on Li1.05Mn2normalO3.96 films prepared by pulsed laser deposition on Pt coated p-doped silicon and cycled in 1 M LiClO4 in propylene carbonate is reported. The formation of the SEI was studied as a function of the voltammetric charging/discharging sweep rate at 40°C in the potential range of 3.5–4.4 V vs Li/Li+ using high resolution scanning electron microscopy and energy-dispersive X-ray spectroscopy. By applying an asymmetric charging/discharging cycle, it is possible to enhance the SEI layer formation. The observed cycling dependence of the SEI is indicative of a continuous formation and degradation process of the SEI depending on the cycling direction and the sweep rate.

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