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The demand of improvement in lithium-ion battery technology in terms of specific capacity and safety has stimulated the search for anode materials alternative to graphite. Among them, tin-based materials have been widely studied because tin can intercalate lithium up to atomic ratio Li/Sn of 4.4 to deliver a impressive specific capacity of 993 mAhg−1 (while graphite gives 372 mAhg−1). Unfortunately the high volume change of about 300%, which is related to the insertion/removal of lithium, causes the alloy pulverization and loss of electric contact that causes a poor cycle life. The synthesis of nanometric materials, intermetallic compounds and carbon composites are strategies that have been pursued to reduce this drawback. In the present study, nanowires of SnCo amorphous alloy grown inside the channels of polycarbonate membrane by potentiostatic deposition were tested as anode for lithium-ion batteries with galvanostatic charge/discharge cycles, demonstrating a capacity corresponding to tin theoretical one stable for over 30 cycles. Even results of nanowires of the same alloy grown on alumina membrane are reported as comparison1. Reference 1. G. Ferrara, C. Arbizzani, L. Damen, R. Inguanta, S. Piazza, C. Sunseri, M. Mastragostino, Nanostructured anode and cathode materials for Li-ion batteries, CIMTEC 2010 5th Forum on New Materials, Montecatini, Italy, June 13-18, 2010

Salt doped poly ethylene oxide (PEO) mixtures were investigated by means of both small angle neutron scattering and QENS techniques aiming to characterize morphological and dynamical features in the melt state. These experimental evidences provide support to the proposed heterogeneous scenario for polymer electrolytes. In particular, the existence of PEO-cation complexes is proposed to play a major role in intramolecular cooperation and intermolecular transient crosslinks. which affects the mixture properties. (C) 2002 Elsevier Science B. V. All rights reserved.

Conjugated polymers with narrow band gap are promising candidates for symmetric electrochemical devices, such as electrochromics and redox supercapacitors, which involve the p- and n-doped state of the polymer. Polydithienothiophene materials which are prepared from isomer monomers show this characteristic. The copolymerisation of two dithienothiophene isomers leads to materials whose electronic properties depend on the monomer ratio. Optical and electrochemical characterizations of different copolymers are reported and discussed.