Michel Armand

Electrochemical method for characterization of graphite-aluminium chloride intercalation compounds

Abstract The electrochemical behaviour of different graphites in molten lithium chloroaluminate electrolyte was studied using the potentiodynamic method. The oxidation currents observed at potentials below chlorine evolution are related to the oxidation of graphite during aluminium chloride intercalation.

Electrochemical Doping of Polycyanoacetylene, A New Conducting Polymer

Abstract Polycyanoacetylene was prepared by dehydrochlorination of poly-α-chloroacrylonitrile at low temperature. Thin films were simply obtained by spreading a DMF solution onto a stainless steel substrate. Transmission electron microscopy revealed a highly crystalline structure. Two different morphologies were observed : large isolated single crystals and numerous small crystals dispersed in the precursor matrix. The electrochemical behaviour of polycyanoacetylene was studied using a (-CH=C(CN)-) /(PEO)8LICIO4/Li cell. Cyclic voltammetry indicated a very reversible behaviour. Lithium intercalation/deintercalation occurred at ca 2.6 V vs Li/Li+. This high value compared to polyacetylene may be attributed to the electron withdrawing effect of the cyano- group. These properties make polycyanoacetylene suitable for use as a positive electrode in batteries.