Influence of polyaniline on electrode materials

Polyaniline (PANI) has been used for modification of the electrochemical behaviour of a carbon fluoride ((CFx)n) cathode in a lithium cell. PANI and (CFx)n powders were carefully mixed and the electrochemical properties and kinetic parameters of the composite (CFx)n–PANI cathode were evaluated by galvanostatic and potentiodynamic techniques. An increase in exchange current has been found for electrodes with addition of polyaniline in the form of emeraldine base (EB). During the reduction process of carbon fluoride using 1 M lithium perchlorate solution in organic solvent, the ternary intercalation compound CLixF is formed and then irreversibly decomposed into carbon and lithium fluoride. The insertion of lithium cations into the (CFx)n layered structure is diffusionally controlled, hence improvement in electronic properties of this fluoride material by the presence of conducting PANI chains and enhancement of discharge performance were found for 25% addition of PANI. Copyright © 1998 John Wiley & Sons, Ltd.