Block copolymer electrolyte with adjustable functional units for solid polymer lithium metal battery  

作　　者：Zhiyuan Lin Xianwei Guo Yubo Yang Mingxue Tang Qi Wei Haijun Yu 

机构地区：[1]College of Materials Sciences and Engineering,Key Laboratory of Advanced Functional Materials,Education Ministry of China,Beijing University of Technology,Beijing 100124,China [2]Center for High Pressure Science&Technology Advanced Research,Beijing 100094,China

出　　处：《Journal of Energy Chemistry》2021年第1期67-74,I0003,共9页能源化学（英文版）

基　　金：supported financially by the National Key R&D Program of China (Grant No. 2018YFB0104300);Beijing Natural Science Foundation (JQ19003, KZ201910005002 and L182009);National Natural Science Foundation of China (Grants 21875007, 51622202, and 21974007);the Project of Youth Talent Plan of Beijing Municipal Education Commission (CIT&TCD201804013)。

摘　　要：Solid polymer electrolytes have been considered as the promising candidates to improve the safety and stability of high-energy lithium metal batteries.However,the practical applications of solid polymer electrolytes are still limited by the low ionic conductivity,poor interfacial contact with electrodes,narrow electrochemical window and weak mechanical strength.Here,a series of novel block copolymer electrolytes with three-dimensional networks are designed by cross-linked copolymerization of the polyethylene glycol soft segments and hexamethylene diisocyanate trimer hard segments.Their ionic migration performances and interface compatibilities with Li metal anode have been optimized delicately by tailoring the ratio of these functional units.The optimized block copolymer electrolyte has shown an amorphous crystalline structure,a high ionic conductivity of ~5.7×10^(-4)S cm^(-1),high lithium ion transference number(~0.49),wide electrochemical window up to ~4.65 V(vs.Li+/Li) and favorable mechanical strength at 55℃.Furthermore,the enhanced interface compatibility can well support the normal operations of lithium metal batteries using both LiFePO4 and LiNi0.8Co0.15Al0.05O2 cathodes.This study not only paves a new way to develop solid polymer electrolyte with optimizing functional units,but also provides a polymer electrolyte design strategy for the application demand of lithium metal battery.

关 键 词：Block copolymer electrolyte Functional units Ionic migration performance Interface compatibility Lithium metal battery 

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]