Concentrated dual-salt electrolytes for improving the cycling stability of lithium metal anodes

• 作者: 刘品 周志彬 方铮 李泓 胡勇胜 陈立泉 马强 马洁 黄学杰
• 来源期刊: 中国物理B（英文版）
• 关键词: lithium metal rechargeable batteries dual-salt electrolyte concentrated electrolytes
• 年，卷（期）: 2016,（7）
• 页码范围: 078203-1-078203-6
• 页数: 1页
• 语种: 英文
• DOI: 10.1088/1674-1056/25/7/078203

摘要

Lithium (Li) metal is an ideal anode material for rechargeable Li batteries, due to its high theoretical specific ca-pacity (3860 mAh/g), low density (0.534 g/cm3), and low negative electrochemical potential (?3.040 V vs. standard hydrogen electrode). In this work, the concentrated electrolytes with dual salts, composed of Li[N(SO2F)2] (LiFSI) and Li[N(SO2CF3)2] (LiTFSI) were studied. In this dual-salt system, the capacity retention can even be maintained at 95.7%after 100 cycles in Li|LiFePO4 cells. A Li|Li cell can be cycled at 0.5 mA/cm2 for more than 600 h, and a Li|Cu cell can be cycled at 0.5 mA/cm2 for more than 200 cycles with a high average Coulombi efficiency of 99%. These results show that the concentrated dual-salt electrolytes exhibit superior electrochemical performance and would be a promising candidate for application in rechargeable Li batteries.