Je-Nam Lee, Gi-Beom Han, Myung-Hyun Ryou
May 30, 2011
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Influential Citations
61
Citations
Journal
Electrochimica Acta
Abstract
Abstract We report N-(triphenylphosphoranylidene) aniline (TPPA) as a new electrolyte additive for high performance lithium cobalt oxide (LiCoO2) electrodes during high voltage operations. When cycled in the voltage range of 3.0–4.4 V, graphite-LiCoO2 full cells with 0.2 wt% TPPA exhibited 10% increased discharge capacities after 200 cycles compared to those of control cells with no such additive. The enhanced cycling performance is attributed to the additive effect toward the modified surface films on LiCoO2 electrodes that suppress the decomposition of both solvent and salt in the electrolyte. This additive effect was characterized by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS).