THE ELECTROCHEMISTRY OF NOBLE-METAL ELECTRODES IN APROTIC ORGANIC-SOLVENTS CONTAINING LITHIUM-SALTS

The electrochemical behavior of various non-aqueous organic electrolyte systems has been investigated using inert metal electrodes. The systems studied included propylene carbonate, dimethoxyethane and tetrahydrofuran solutions of LiClO4, LiAsF6, LiSO3CF3 and Bu4NClO4. The electrode metals included polycrystalline gold and silver. Various techniques including cyclic voltammetry, FTIR and XPS were used to characterize the main electrochemical reactions that occur in these systems. Several separate film forming processes have been identified, including reduction of solvent, the salt, and traces of oxygen and water. The surface films formed in these processes lead to the apparent stability of these systems at low potentials. Li UPD was also examined and was found to be controlled by the nature of the surface films through which lithium is deposited.