A Thermally Conductive Separator for Safe Lithium Metal Batteries

作者：Tao Wang, Zezhong Shi, Bo Xu, Yechao Qin, Feng Jiang, Huchong Yao, Xiaosong Xiong, Zhenhua Gao, Qiqi Jiang, Bangyue Mou, Yuan Ma, Xin-Bing Cheng, Yuping Wu · 发表于：ACS Energy Letters · 年份：2026 · DOI：10.1021/acsenergylett.6c00276 · 被引用次数：3 · 研究领域：Advanced Battery Materials and Technologies、Extraction and Separation Processes、Advanced Battery Technologies Research

Lithium metal batteries (LMBs) have demonstrated potential for energy storage but face significant thermal safety concerns. Here, we report a thermally conductive trifunctional separator, composed of hexagonal boron nitride and poly(vinylidene fluoride)-hexafluoropropylene (BN/PH), as a dendrite suppression layer, temperature regulation layer, and thermal protection layer to enhance the thermal safety and electrochemical performance of LMBs. The customized BN/PH separator shows a Li + transference number (0.55) and promotes uniform lithium deposition, resulting in 1800 h cycles in the Li/Li symmetric cell with low overpotential (14 mV). Importantly, it demonstrates a thermal conductivity of 117.76 W m –1 K –1 in the XY -plane for rapid heat dissipation and prevents short circuits at elevated temperature (>180 °C), significantly increasing the thermal runaway onset temperature from 119.3 to 196.7 °C in cycled pouch cells. This work underscores the critical role of thermally conductive separators in ensuring the thermal safety of LMBs.