Stabilizing LiCoO2 (LCO) cathode at high voltages is still challenging in lithium‐ion batteries (LIBs). Although fluorinated solvents are utilized in high‐voltage systems for their superior oxidation resistance, linear fluorinated carbonates still undergo elimination reactions at high voltages, producing corrosive substances that compromise electrode materials. This study addresses the elimination reaction of methyl trifluoroethyl carbonate (FEMC) by incorporating tris(trimethylsilyl)‐based additives, thereby constructing a homogeneous and robust polymer‐rich cathode‐electrolyte interphase (CEI). With the incorporation of tris(trimethylsilyl)phosphite in the optimized electrolyte, the capacity of the coin cell with LCO as the cathode can maintain 95% after 500 cycles with a high cut‐off voltage of 4.6 V. This study establishes a foundational framework for employing linear fluorocarbonates in high‐voltage systems and provides innovative insights into CEI design and construction.

中文翻译：

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利用线性氟化碳酸酯的消除反应将 LiCoO2 阴极稳定在 4.6 V 以下


在锂离子电池 （LIB） 中，在高电压下稳定 LiCoO2 （LCO） 阴极仍然具有挑战性。尽管氟化溶剂因其卓越的抗氧化性而被用于高压系统，但线性氟化碳酸盐在高压下仍会发生消除反应，产生腐蚀物质，从而损害电极材料。本研究通过掺入基于三（三甲基硅烷基）的添加剂来解决碳酸三氟乙酯 （FEMC） 的消除反应，从而构建均匀且坚固的富含聚合物的阴极电解质界面 （CEI）。通过在优化的电解液中掺入亚磷酸三（三甲基硅烷基）电池，以 LCO 为阴极的纽扣电池在 4.6 V 的高截止电压下，经过 500 次循环后，其容量可以保持 95%。本研究为在高压系统中使用线性碳氟碳酸盐建立了基础框架，并为 CEI 设计和施工提供了创新见解。