A surfactant-modified composite separator for high safe lithium ion battery  

作　　者：Botao Yuan Niandong He Yifang Liang Liwei Dong Jipeng Liu Jiecai Han Weidong He Yuanpeng Liu 

机构地区：[1]National Key Laboratory of Science and Technology on Advanced Composites in Special Environments,Center for Composite Materials and Structures,Harbin Institute of Technology,Harbin 150080,Heilongjiang,China [2]MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage,School of Chemistry and Chemical Engineering,Harbin Institute of Technology,Harbin 150080,Heilongjiang,China [3]Chongqing Research Institute,Harbin Institute of Technology,Chongqing 401151,China

出　　处：《Journal of Energy Chemistry》2023年第1期398-403,I0010,共7页能源化学（英文版）

基　　金：supported by the Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments;the National Natural Science Foundation of China(12002109);the China Postdoctoral Science Foundation(2020M670898);the Heilongjiang Postdoctoral Fund(LBH-Z20060)。

摘　　要：Separators have been gaining increasing attention to improve the performance of lithium ion batteries(LIBs),especially for high safe and long cycle life.However,commercial polyolefin separators still face the problems of rapid capacity decay and safety issues due to the poor wettability with electrolytes and low thermal stability.Herein,a novel composite separator is proposed by introducing a surfactant of sodium dodecyl thiosulfate(SDS)into the polytetrafluoroethylene(PTFE)substrate with the binder of polyacrylic acid(PAA)through the suction filtration method.The introduction of PAA/SDS enhances the adsorption energy between PTFE substrate and electrolyte through density functional theory calculations,which improves wettability and electrolyte uptake of the separator significantly.The asachieved composite separator enables the LIBs to own high Li^(+)conductivity(0.64×10^(-3)S cm^(-1))and Li^(+)transference number(0.63),further leading to a high capacity retention of 93.50%after 500 cycles at 1 C.In addition,the uniform and smooth surface morphology of Li metal employed the composite separator after cycling indicates that the lithium dendrites can be successfully inhibited.This work indicates a promising route for the preparation of a novel composite separator for high safe LIBs.

关 键 词：Composite separator PTFE SURFACTANT High safe Lithium ion batteries 

分 类 号：TM912[电气工程—电力电子与电力传动]