Safety-enhanced Polymer Electrolytes with High Ambient-temperature Lithium-ion Conductivity Based on ABA Triblock Copolymers  

作　　者：Dong Liu Fan Wu Zhi-Hao Shen Xing-He Fan 

机构地区：[1]Beijing National Laboratory for Molecular Sciences,Key Laboratory of Polymer Chemistry and Physics of Ministry of Education,Center for Soft Matter Science and Engineering,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China

出　　处：《Chinese Journal of Polymer Science》2022年第1期21-28,共8页高分子科学（英文版）

基　　金：financially supported by the National Key R&D Program of China(No.2018YFB0703702);the National Natural Science Foundation of China(Nos.21774001,51725301 and 51921002)。

摘　　要：Liquid electrolytes used in lithium-ion batteries suffer from leakage,flammability,and lithium dendrites,making polymer electrolyte a potential alternative.Herein,a series of ABA triblock copolymers(ABA-x)containing a mesogen-jacketed liquid crystalline polymer(MJLCP)with a polynorbornene backbone as segment A and a second polynorbornene-based polymer having poly(ethylene oxide)(PEO)side chains as segment B were synthesized through tandem ring-opening metathesis polymerizations.The block copolymers can self-assemble into ordered morphologies at 200℃.After doping of lithium salts and ionic liquid(IL),ABA-x self-assembles into cylindrical structures.The MJLCP segments with a high glass transition temperature and a stable liquid crystalline phase serve as physical crosslinking points,which significantly improve the mechanical performance of the polymer electrolytes.The ionic conductivity of ABA-x/lithium salt/IL is as high as 10-3 S·cm-1 at ambient temperature owing to the high IL uptake and the continuous phase of conducting PEO domains.The relationship between ionic conductivity and temperature fits the Vogel-Tamman-Fulcher(VTF)equation.In addition,the electrolyte films are flame retardant owing to the addition of IL.The polymer electrolytes with good safety and high ambient-temperature ionic conductivity developed in this work are potentially useful in solid lithium-ion batteries.

关 键 词：ABA triblock copolymer Polymer electrolyte Ionic conductivity Inflammability Cylindrical structure 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ317[化学工程—高聚物工业]