Safe and Stable Lithium Metal Batteries Enabled by an Amide?Based Electrolyte

• 作者: Wanbao Wu Yiyang Bo Deping Li Yihong Liang Jichuan Zhang Miaomiao Cao Ruitian Guo Zhenye Zhu Lijie Ci Mingyu Li Jiaheng Zhang
• 来源期刊: 纳微快报（英文版）
• 年，卷（期）: 2022,（3）
• 页码范围: 120-133
• 页数: 14页
• 语种: 英文

摘要

The formation of lithium dendrites and the safety hazards arising from flammable liquid electrolytes have seri-ously hindered the development of high-energy-density lithium metal batteries. Herein, an emerging amide-based electrolyte is proposed, containing LiTFSI and butyrolactam in different molar ratios. 1,1,2,2-Tetrafluoroethyl-2,2,3,3-tetrafluoropropylether and fluoroethylene carbonate are introduced into the amide-based elec-trolyte as counter solvent and additives. The well-designed amide-based electrolyte possesses nonflammability, high ionic conductiv-ity, high thermal stability and electrochemical stability (> 4.7 V). Besides, an inorganic/organic-rich solid electrolyte interphase with an abundance of LiF, -Li3N and Li–N–C is in situ formed, leading to spherical lithium deposition. The formation mechanism and solvation chemistry of amide-based electrolyte are further inves-tigated by molecular dynamics simulations and density functional theory. When applied in Li metal batteries with -LiFePO4 and -LiMn2O4 cathode, the amide-based electrolyte can enable stable cycling performance at room temperature and 60 ℃. This study provides a new insight into the development of amide-based electrolytes for lithium metal batteries.