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Cathode material for Li-ion batteries can be synthesised by r.f. magnetron sputtering of LiCoO 2 targets in a pure Ar plasma. This technique is suitable for large-scale implementation in foil coating set-ups. By choosing the process parameters and by employing post heat treatment nanocrystalline, stoichiometrical LiCoO 2 films can be fabricated which exhibit the desired high temperature phase. The determination of the elementary composition is possible by optical emission spectroscopy including plasma stimulation and carrier gas temperature extraction. The proof of crystal structure is carried out by X-ray diffraction and Raman spectroscopy. Heat treatment can be conventionally realised in a furnace or by laser impact. With regard to increasing the power density, the surface of the cathode material can be enhanced six-fold by laser-assisted surface patterning.

Nanosized crystalline Fe3O4 (with an average particle size of 16 nm) was successfully synthesized on a carbon matrix surface. The prepared sample was heat-treated in the temperature range 300 degrees C - 750 degrees C to remove residual impurities and to obtain a final product with a 77:23 ratio between magnetite and the carbon support. The sample was subjected to physicochemical and electrochemical tests. The purity of the phase and the particles size was determined by X-ray diffraction analysis and confirmed by field emission scanning electron micrographs. The specific surface area of the sample measured by the B.E.T method was 120 m2 g(-1). A series of electrochemical tests including EIS, CV and long-term constant current cycling have been performed. The obtained reversible capacity within 15 cycles was in the range 400-550 mA h x g(-1). The electrochemical behavior of the test sample and its possible practical use as an anode material in lithium secondary batteries are discussed.

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