Bipolar Polymeric Protective Layer for Dendrite‐Free and Corrosion‐Resistant Lithium Metal Anode in Ethylene Carbonate Electrolyte

作者：Chenglong Deng, Binbin Yang, Yaohui Liang, Yi Zhao, Boshun Gui, Chuanyu Hou, Yanxin Shang, Jinxiang Zhang, Tinglu Song, Xuzhong Gong, Nan Chen, Feng Wu, Renjie Chen · 发表于：Angewandte Chemie International Edition · 年份：2024 · DOI：10.1002/anie.202400619 · 被引用次数：32 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Advanced Battery Technologies Research

Abstract The unstable interface between Li metal and ethylene carbonate (EC)‐based electrolytes triggers continuous side reactions and uncontrolled dendrite growth, significantly impacting the lifespan of Li metal batteries (LMBs). Herein, a bipolar polymeric protective layer (BPPL) is developed using cyanoethyl (−CH 2 CH 2 C≡N) and hydroxyl (−OH) polar groups, aiming to prevent EC‐induced corrosion and facilitating rapid, uniform Li + ion transport. Hydrogen‐bonding interactions between −OH and EC facilitates the Li + desolvation process and effectively traps free EC molecules, thereby eliminating parasitic reactions. Meanwhile, the −CH 2 CH 2 C≡N group anchors TFSI − anions through ion‐dipole interactions, enhancing Li + transport and eliminating concentration polarization, ultimately suppressing the growth of Li dendrite. This BPPL enabling Li|Li cell stable cycling over 750 cycles at 10 mA cm −2 for 2 mAh cm −2 . The Li|LiNi 0.8 Mn 0.1 Co 0.1 O 2 and Li|LiFePO 4 full cells display superior electrochemical performance. The BPPL provides a practical strategy to enhanced stability and performance in LMBs application.