Localized high-concentration electrolytes (LHCEs) have been proposed for lithium metal batteries (LMBs) to control the solvation structure of the lithium ions and consequently the solid–electrolyte-interphase (SEI) composition. Although this approach extends the cycle life effectively, the fluorinated diluents in LHCEs severely corrode metallic Li via spontaneous chemical decomposition, which shortens the calendar life. Here, we introduce an LHCE containing hexafluoroisopropyl methyl ether (HFME) as the diluent to which n-hexane has been added. n-Hexane serves as a kinetic barrier in the “swollen” SEI to suppress the Li corrosion by HFME. A galvanostatically cycled full-cell that includes n-hexane, with an 8-hour rest period inserted at the end of each charge, has a markedly improved calendar life compared to its hexane-free counterpart (80.8% retention after 160 cycles vs. 6.0% retention after 46 cycles). This study reveals the usefulness of introducing an inert hydrocarbon to enhance both the cycle life and calendar life of LHCE-based LMBs.

中文翻译：

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防腐蚀电解液设计，延长锂金属电池的日历寿命


已提出将局部高浓度电解质（LHCE）用于锂金属电池（LMB），以控制锂离子的溶剂化结构，从而控制固体电解质界面（SEI）的组成。尽管这种方法有效地延长了循环寿命，但LHCE中的氟化稀释剂通过自发化学分解严重腐蚀金属锂，从而缩短了日历寿命。在此，我们介绍一种以六氟异丙基甲基醚（HFME）为稀释剂并添加了正己烷的LHCE。正己烷作为“膨胀”SEI 中的动力学屏障，抑制 HFME 引起的锂腐蚀。包含正己烷的恒电流循环全电池，在每次充电结束时插入 8 小时休息期，与不含己烷的同类产品相比，日历寿命显着延长（160 次循环后保留率为 80.8%，循环后保留率为 6.0%）。 46 个循环后的保留百分比）。这项研究揭示了引入惰性碳氢化合物对于提高基于 LHCE 的 LMB 的循环寿命和日历寿命的有用性。