Molecular Engineering Enabled Stable Deep Eutectic Amide-Based Electrolyte for High-Temperature Lithium–Metal Batteries
Yuanxin Gao, Lingyu Zhu, Bingning Wang, Yuanjian Xu, Jingchao Chai, Aiping Fu, Hao Li, Jiangpeng Li, Peng Yu, Yun Zheng, Yingying Wang, Jin Yong Lee, Dong Lv, Zhihong Liu
Abstract
High Resolution Image Download MS PowerPoint Slide The development of advanced lithium–metal batteries (LMBs), such as high-temperature LMBs and high-energy-density LMBs, has critical requirements for electrolytes. However, conventional electrolytes suffer from thermal instability and insufficient electrolyte/Li interfacial compatibility, severely limiting their utilization in high-temperature LMBs. Herein, we design a high-temperature N -methylacetamide (NMAc)-based deep eutectic electrolyte (DEE) by molecular engineering on a solvation structure via a sacrificial additive of vinyl ethylene carbonate (VEC). Specifically, VEC interacts with the Li prior to NMAc, facilitating the formation of a solid electrolyte interphase to inhibit the reaction between Li and NMAc. The stable VEC-DEE effectively suppresses the growth of lithium dendrites and ensures the battery a cycling stability of 550 cycles at 80 °C. Additionally, we also demonstrate the application of VEC-DEE in high-energy-density LMBs with a high mass loading of 2.5 mAh/cm 2 . This research opens a new avenue for the rational design of advanced high-temperature electrolytes.