ANODIC-OXIDATION MECHANISM OF PROPYLENE C ARBONATE PLUS 1,2-DIMETHOXYETHANE ELECTROLYTIC SOLUTIONS

Electrochemical stability of propylene carbonate (PC)+1,2-dimethoxyeth ane (DME), PC and ethylene carbonate (EC)+DME containing LiPF6 under a nodic polarization of Pt electrodes was investigated by means of cycli c voltammetry, chronoamperometry and nuclear magnetic resonance (NMR) spectroscopy. Anodic oxidation current densities of these solvents at potentials lower than 5.0 V vs. Li/Li+ increased in the following orde r: PC<EC<DME. The NMR measurement shows that anodic oxidation of DME w as predominant in LiPF6-containing PC+DME solutions up to 5.0 V vs. Li /Li+ because of a less electrochemical stability of DME than LiPF6 and PC. DME molecules underwent the non-electrochemical polymerization yi elding the products containing -OCH3 and -OCH2-groups.