Paper Title
Effects of Air Electrode and Aprotic Solvent on Lithium-Oxygen Battery Performance

Abstract
Lithium-oxygen battery has a high power density and has good potential for commercial energy storage device. In the rechargeable lithium-air battery, electrolyte and electrode play important roles to supply ion transport paths, to maintain sufficient conductivity, and to enable electrochemical reactions. The objective of this research is to investigate various designs of lithium air battery: including the use of microporous hydrophobic layer and different aprotic solvent. The effects of these constituents on the capacity and cycle life of lithium-oxygen batteries using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/tetraethylene glycol dimethyl ether (tetraglyme) or diethylene glycol dimethyl ether electrolyte are investigated. The aged electrodes after discharge/charge cycles were examined for morphology and elemental composition. The best performance was resulted from applying catalyst on carbon cloth containing microporous hydrophobic layer and employing tetraglyme solvent. A capacity of 2000 mAh/g-Pt for 15 cycles (300 h) at current density of 0.05 mA/cm2 were obtained. Lithium carbonate deposits were observed after cycling test, especially on the surface toward oxygen inlet.These carbonate deposits may lead to battery failure. Therefore catalyst on the surface toward air inlet is recommend for future study Index Terms - Lithium-oxygen battery, Organic electrolyte, Electrode structure, Battery aging.