• The cycle performance of poly(ethylene oxide) (PEO)-based all-solid-state lithium batteries with LiCoO₂ cathode was greatly improved via coating LiCoO₂ with high-voltage stable Li₃AlF₆.

• At the upper cutoff voltage of 4.2 V, the poor electrochemical performance is mainly originated from the structure collapse of LiCoO₂ at the surface instead of the decomposition of PEO.

• When the voltage reaches 4.5 V or even higher potentials, the intensive electrochemical decomposition of PEO-based solid polymer electrolyte accelerated interfacial degradation.

中文翻译：

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洞察高压全固态锂电池的界面退化

• _{以LiCoO 2}为正极的聚环氧乙烷(PEO)基全固态锂电池的循环性能通过在LiCoO ₂上包覆耐高压的Li ₃ AlF ₆得到了极大的改善。

• 在4.2 V的上限截止电压下，较差的电化学性能主要源于表面LiCoO ₂的结构坍塌，而不是PEO的分解。

• 当电压达到 4.5 V 甚至更高的电位时，PEO 基固体聚合物电解质的强烈电化学分解加速了界面降解。