We report the first successful preparation of thin films of Y-Ba-Cu-O superconductors using pulsed excimer laser evaporation of a single bulk material target in vacuum. Rutherford backscattering spectrometry showed the composition of these films to be close to that of the bulk material. Growth rates were typically 0.1 nm per laser shot. After an annealing treatment in oxygen the films exhibited superconductivity with an onset at 95 K and zero resistance at 85 and 75 K on SrTiO3 and Al2O3 substrates, respectively. This new deposition method is relatively simple, very versatile, and does not require the use of ultrahigh vacuum techniques.

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We describe synchroton based X-ray diffraction techniques and issues related to in situ studies of intercalation processes in battery electrodes. We then demonstrate the utility of this technique, through a study of two batches of LiMn2O4 cathode materials. The structural evolution of these spinel materials was monitored in situ during the initial charge of these electrodes in actual battery cells. Significant differences were observed in the two batches, particularly in the intercalation range of x = 0.45 to 0.20. The first-order structural transitions in this region indicated coexistence of two cubic phases in the batch 2 material, whereas the batch 1 material showed suppressed two-phase coexistence. Batch 2 cells also indicated structural evolution in the low-potential region below 3.0 V in contrast to the batch 1 material. Differences in structural evolution between batches of LiMn2O, could have important ramifications in their cycle life and stability characteristics. 466 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.48.29.181 Downloaded on 2014-11-03 to IP 10 x-ray photon energy (keY) 100 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.48.29.181 Downloaded on 2014-11-03 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.48.29.181 Downloaded on 2014-11-03 to IP ABSTRACTChemical reactions taking place at elevated temperatures in a polymer-bonded lithiated carbon anode were studied by differential scanning calorimetry. The influences of parameters such as degree of intercalation, number of cycles, specific surface area, and chemical nature of the binder were elucidated. It was clearly established that the first reaction taking place at ca. 120-140 °C was the transformation of the passivation layer products into lithium carbonate, and that lithiated carbon reacted with the molten binder via dehydrofluorination only at T> 300 °C. Both reactions strongly depend on the specific surface area of the electrodes and the degree of lithiation.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.48.29.181 Downloaded on 2014-11-03 to IP