Tian Kaixin, Wang Mingshan, Hu Rui, Li Xinpeng, He Yike, Song Jialin, Zhao Bo, Luo Pan, Li Xing, Cao Guozhong
School of New Energy and Materials, Southwest Petroleum University, Chengdu, Sichuan 610500, P. R. China.
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, P. R. China.
ACS Nano. 2025 Aug 5;19(30):27768-27781. doi: 10.1021/acsnano.5c07967. Epub 2025 Jul 22.
The advancement of quasi-solid lithium metal batteries strongly hinges on attaining fast Li transport, stable electrode/electrolyte interphases, and high safety. The present study reports a high-continuous Li coordination polymer electrolyte composed of a poly(1,3,5-trioxane) (PTXE) skeleton and mixed solvent of triethyl phosphate (TEP) and fluoroethylene carbonate (FEC). The continuous ether chains (-[C-O]-) in PTXE coordinated with binary solvents and anions of dual lithium salt (TFSI and DFOB) optimize the solvent structure and establish rapid Li migration, achieving high Li conductivity (1.87 mS cm at 25 °C) and Li transference number (0.64) prior to the liquid electrolyte. Simultaneously, via the synergistic induction and regulation exerted by polymer chain segments on the coordination of solvents and anions around Li, phosphorus- and fluorine-rich cathodic and anodic electrolyte interphases are formed. Furthermore, flame-retardant TEP significantly improves the thermal stability at high temperature (60 °C) as well as under harsh mechanical testing. The assembly of a lithium metal battery with high loading mass of LiNiCoMnO (10 mg cm) and ultrathin Li (50 μm) exhibits a high capacity retention rate of 87.1% with 120 cycles. Furthermore, a large-capacity pouch cell (7 Ah) with Li||LiNiCoMnO (40 mg cm) achieves high reversible capacity (6.58 Ah) with a high energy density of 505 Wh kg.
准固态锂金属电池的发展很大程度上取决于实现快速的锂传输、稳定的电极/电解质界面以及高安全性。本研究报道了一种由聚（1,3,5-三氧杂环己烷）（PTXE）骨架以及磷酸三乙酯（TEP）和氟代碳酸乙烯酯（FEC）的混合溶剂组成的高连续性锂配位聚合物电解质。PTXE中的连续醚链（-[C-O]-）与二元溶剂以及双锂盐（TFSI和DFOB）的阴离子配位，优化了溶剂结构并建立了快速的锂迁移，在液态电解质之前实现了高锂电导率（25℃下为1.87 mS cm）和锂迁移数（0.64）。同时，通过聚合物链段对锂周围溶剂和阴离子配位的协同诱导和调节，形成了富含磷和氟的阴极和阳极电解质界面。此外，阻燃性的TEP显著提高了在高温（60℃）以及苛刻机械测试条件下的热稳定性。组装具有高负载质量的LiNiCoMnO（10 mg cm）和超薄锂（50μm）的锂金属电池，在120次循环后表现出87.1%的高容量保持率。此外，具有Li||LiNiCoMnO（40 mg cm）的大容量软包电池（7 Ah）实现了6.58 Ah的高可逆容量，能量密度高达505 Wh kg。
