High-performance localized high-concentration electrolytes by diluent design for long-cycling lithium metal batteries  

作　　者：Zhe Wang Li-Peng Hou Qian-Kui Zhang Nan Yao Aibing Chen Jia-Qi Huang Xue-Qiang Zhang 

机构地区：[1]College of Chemical and Pharmaceutical Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China [2]Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology,Department of Chemical Engineering,Tsinghua University,Beijing 100084,China [3]Advanced Research Institute of Multidisciplinary Science,Beijing Institute of Technology,Beijing 100081,China [4]School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China

出　　处：《Chinese Chemical Letters》2024年第4期244-247,共4页中国化学快报（英文版）

基　　金：supported by National Key Research and Development Program (Nos.2021YFB2500300 and 2021YFB2400300);Beijing Natural Science Foundation (No.JQ20004);S&T Program of Hebei (No.22344402D);National Natural Science Foundation of China (Nos.22209010 and 22109007);China Postdoctoral Science Foundation (No.2021M700404);Beijing Institute of Technology Research Fund Program for Young Scholars。

摘　　要：Electrolyte design is essential for stabilizing lithium metal anodes and localized high-concentration electrolyte(LHCE) is a promising one. However, the state-of-the-art LHCE remains insufficient to ensure long-cycling lithium metal anodes. Herein, regulating the solvation structure of lithium ions in LHCE by weakening the solvating power of diluents is proposed for improving LHCE performance. A diluent,1,1,2,2,3,3,4,4-octafluoro-5-(1,1,2,2-tetrafluoroethoxy) pentane(OFE), with weaker solvating power is introduced to increase the proportion of aggregates(an anion interacts with more than two lithium ions,AGG-n) in electrolyte compared with the commonly used 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether(TTE). The decomposition of AGG-n in OFE-based LHCE intensifies the formation of anion-derived solid electrolyte interphase and improves the uniformity of lithium deposition. Lithium metal batteries with OFE-based LHCE deliver a superior lifespan of 190 cycles compared with 90 cycles of TTE-based LHCE under demanding conditions. Furthermore, a pouch cell with OFE-based LHCE delivers a specific energy of 417 Wh/kg and undergoes 49 cycles. This work provides guidance for designing high-performance electrolytes for lithium metal batteries.

关 键 词：Lithium metal anodes ELECTROLYTE DILUENTS Solid electrolyte interphase Pouch cells 

分 类 号：O646[理学—物理化学] TM912[理学—化学]