writer：Panpan Dong, Shangzhang Yu, Xuemeng Gan, Qilin He, Xiaojie Zheng, He Lin, Xiaoping Wang, Qiao Lin, Liangjie Gu, Qingsong Zhang, Weiqing Yang
keywords：Lithium magnesium silicate，Poly(ethylene) oxide，Ion transport，Thermal stability，Solid-state lithium metal batteries
source：期刊
Issue time：2026年

Poly(ethylene) oxide (PEO)-based electrolytes have been widely studied for solid-state lithium batteries due to their good flexibility and compatibility with lithium metal, while their ionic conductivity and thermal stability still need to be further improved. Herein, we report a PEO-based composite electrolyte (denoted as PTLL) reinforced with thermoplastic polyurethane and two-dimensional lithium magnesium silicate (LMS, Li2Mg2 Si3O9) for solid-state lithium metal batteries. The incorporation of LMS and the polymer blend effectively reduces the crystallinity of PEO matrix while significantly enhancing the mechanical strength of PTLL electrolyte. Additionally, the PTLL exhibits a high ionic conductivity (2.48 × 10-4 S cm-1 at 30 ?C), enhanced thermal stability (150 ?C), and a higher onset oxidative voltage (>4.2 V) when compared to conventional PEO electro lytes (1.06 × 10-5 S cm-1 at 30 ?C; onset oxidative voltage at 3.83 V). Furthermore, symmetrical lithium cell with the robust PTLL electrolyte demonstrates good cycling stability up to 800 h with a stable polarization voltage, indicating good compatibility of PTLL with lithium metal. As a result, Li/LiFePO4 cell with PTLL electrolyte exhibits a much higher specific capacity of 165.5 mAh g-1 at 0.1 C and better reversibility at 0.5 C with a high average Coulombic efficiency > 99.8 % at 60 ?C than those of conventional PEO electrolyte. Moreover, the PTLL-based Li/NCM811 cell enables a high specific capacity of 155.4 mAh g-1 at 0.1 C. This work also provides a promising strategy for designing advanced composite electrolytes toward high-performance solid-state lithium metal batteries