IN-SITU SCANNING VIBRATING ELECTRODE TECHNIQUE FOR LITHIUM METAL ANODES

The effect of the inorganic additives to electrolytes, aluminum iodide (AlI3) and tin(II) iodide, on the charge/discharge coulombic efficien cy of a lithium (Li) metal anode has been investigated in binary solve nt systems, i.e., propylene carbonate (PC) mixed with 2-methyltetrahyd rofuran (2Me-THF) containing lithium perchlorate (:LiClO4), PC + 2Me-T HF/LiClO4,, and PC mixed with 1,2-dimethoxyethane (DME) containing LiC lO4,, PC + DME/LiClO4,,. AlI3 improved the coulombic efficiency of the Li metal anode in both the binary solvent systems. Two-dimensional Li ionic currents at the interface of the Li metal anode were monitored by using in situ scanning vibrating electrode technique (SVET) in the representative binary system, PC + 2Me-THF/LiClO4,, in;he absence and presence of the additives. The relationship between the coulombic effi ciency and the Li ionic current distribution on the anode was discusse d. (C) 1997 Published by Elsevier Science S.A.