A combined experimental and theoretical study of surface film formation: Effect of oxygen on the reduction mechanism of propylene carbonate

详细信息    查看全文

• 作者：Atetegeb Meazah Haregewoin ; Ermias Girma Leggesse ; Jyh-Chiang Jiang ; Fu-Ming Wang ; Bing-Joe Hwang ; Shawn D. Lin
• 关键词：Lithium-ion battery ; Propylene carbonate ; Reductive decomposition ; Solid electrolyte interphase
• 刊名：Journal of Power Sources
• 出版年：2013
• 出版时间：15 December, 2013
• 年：2013
• 卷：244
• 期：Complete
• 页码：318-327
• 全文大小：1820 K

文摘

Combining experimental and computational techniques can provide a better understanding of surface film formation processes that occur in the lithium-ion battery. In this paper, we show that this joint approach can provide a mechanistic understanding of the effect of oxygen in the reduction of propylene carbonate (PC). We perform FTIR analysis, inside a glove box, after conducting linear sweep voltammetry (LSV) from an open-circuit voltage (OCV) to selected potential regions; subtraction between two successive IR spectra has been made to identify the reduction products formed within each potential range. FTIR analysis in the potential range from OCV to ?0.1?V, in conjunction with density functional theory (DFT) calculations, confirm the formation of solvated Li₂CO₃ and (PC)₂LiOC(O)OCH(CH₃)CH₂OLi(PC) due to PC reduction. Our experimental results and DFT calculations suggest that in the potential range from OCV to 1.6?V, PC, in the presence of O₂, can easily decompose by the superoxide ion through a nucleophilic attack at the ethereal carbon atom.