This work demonstrates the low-temperature operation of solid-state lithium metal batteries (LMBs) through the development of a fluorinated and plastic-crystal-embedded elastomeric electrolyte (F-PCEE). The F-PCEE is formed via polymerization-induced phase separation between the polymer matrix and plastic crystal phase, offering a high mechanical strain (≈300%) and ionic conductivity (≈0.23 mS cm⁻¹) at −10 °C. Notably, strong phase separation between two phases leads to the selective distribution of lithium (Li) salts within the plastic crystal phase, enabling superior elasticity and high ionic conductivity at low temperatures. The F-PCEE in a Li/LiNi_0.8Co_0.1Mn_0.1O₂ full cell maintains 74.4% and 42.5% of discharge capacity at −10 °C and −20 °C, respectively, compared to that at 25 °C. Furthermore, the full cell exhibits 85.3% capacity retention after 150 cycles at −10 °C and a high cut-off voltage of 4.5 V, representing one of the highest cycling performances among the reported solid polymer electrolytes for low-temperature LMBs. This work attributes the prolonged cycling lifetime of F-PCEE at −10 °C to the great mechanical robustness to suppress the Li-dendrite growth and ability to form superior LiF-rich interphases. This study establishes the design strategies of elastomeric electrolytes for developing solid-state LMBs operating at low temperatures and high voltages.

中文翻译：

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低温高电压固态锂金属电池氟化弹性电解质的设计

我们通过开发氟化塑料晶体嵌入弹性体电解质（F-PCEE）展示了固态锂金属电池（LMB）的低温运行。 F-PCEE是通过聚合物基体和塑料晶相之间聚合诱导的相分离形成的，具有高机械应变（~300%）和离子电导率（~0.23 mS cm）−1）在‐10°C。值得注意的是，两相之间的强烈相分离导致锂（Li）盐在塑料晶相内选择性分布，从而在低温下实现优异的弹性和高离子电导率。 Li/LiNi 中的 F-PCEE0.8钴0.1锰0.1氧2与 25 °C 时相比，全电池在 ‐10 和 ‐20 °C 下分别保持 74.4% 和 42.5% 的放电容量。此外，在‐10°C和4.5V的高截止电压下循环150次后，全电池表现出85.3%的容量保持率，代表了已报道的低温LMB固体聚合物电解质中最高的循环性能之一。我们将 F-PCEE 在 ‐10 °C 下的循环寿命延长归因于抑制锂枝晶生长的出色机械鲁棒性以及形成优异的富 LiF 界面的能力。这项研究建立了弹性体电解质的设计策略，用于开发在低温和高电压下工作的固态LMB。本文受版权保护。版权所有