Full Dissolution of the Whole Lithium Sulfide Family (Li2S8to Li2S) in a Safe Eutectic Solvent for Rechargeable Lithium–Sulfur Batteries

作     者：Qian Cheng Weiheng Xu Shiyi Qin Subhabrata Das Tianwei Jin Aijun Li Alex Ceng Li Boyu Qie Pengcheng Yao Haowei Zhai Changmin Shi Xin Yong Yuan Yang 

作者机构：Program of Materials Science and Engineering Department of Applied Physics and Applied Mathematics Columbia University 500 W 120th St New York NY 10027 USA Department of Mechanical Engineering The State University of New York Binghamton 85 Murray Hill Rd. Suite 1300 Rm#1320 Binghamton NY 13902 USA Langmuir Center of Colloids and Interfaces Columbia University 500 W 120th St New York NY 10027 USA 

出 版 物：《Angewandte Chemie》 

年 卷 期：2019年第131卷第17期

学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 

主　　题：Elektrolyte Eutektische Lösungsmittel Feuerschutzmittel Lithium-Schwefel-Batterien Sicherheit 

摘      要：The lithium–sulfur battery is an attractive option for next‐generation energy storage owing to its much higher theoretical energy density than state‐of‐the‐art lithium‐ion batteries. However, the massive volume changes of the sulfur cathode and the uncontrollable deposition of Li 2 S 2 /Li 2 S significantly deteriorate cycling life and increase voltage polarization. To address these challenges, we develop an ϵ‐caprolactam/acetamide based eutectic‐solvent electrolyte, which can dissolve all lithium polysulfides and lithium sulfide (Li 2 S 8 –Li 2 S). With this new electrolyte, high specific capacity (1360 mAh g −1 ) and reasonable cycling stability are achieved. Moreover, in contrast to conventional ether electrolyte with a low flash point (ca. 2 °C), such low‐cost eutectic‐solvent‐based electrolyte is difficult to ignite, and thus can dramatically enhance battery safety. This research provides a new approach to improving lithium–sulfur batteries in aspects of both safety and performance.