Water-Stable Lithium Anode with the Three-Layer Construction for Aqueous Lithium-Air Secondary Batteries

摘要

A water-stable multilayer Li-metal electrode consisting of a lithium metal, a PEO18LiN(SO2CF3)(2)-BaTiO3 composite polymer, and a lithium-conducting glass ceramic Li1.35Ti1.75Al0.25P0.9Si0.1O12 (LTAP) was proposed as the lithium anode for aqueous lithium-air secondary batteries. The addition of finely dispersed nanosize BaTiO3 in the polymer electrolyte greatly reduced the interfacial resistance between the Li anode and the polymer electrolyte. A Li/PEO18LiN(SO2CF3)(2)-10 wt % BaTiO3/LTAP electrode showed a total resistance of 175 Omega cm(2) in a 1 M aqueous LiCl solution at 60 degrees C, with no change in the electrode resistance over a month. The Li/PEO18LiN(SO2CF3)(2)-10 wt % BaTiO3/LTAP/aqueous 1 M LiCl/Pt air cell had a stable open-circuit voltage of 3.80 V, which was equivalent to that calculated from the cell reaction of 2Li+1/2O(2)+H2O=2LiOH. The cell exhibited a stable and reversible discharge/charge performance of 0.5 mA cm(-2) at 60 degrees C, suggesting excellent reversibility of the lithium oxidation reduction reaction for the Li/PEO18LiN(SO2CF3)(2)-10 wt % BaTiO3/LTAP electrode.