IMPROVING THE PROPERTIES OF HDPE BASED SEPARATORS FOR LITHIUM ION BATTERIES BY BLENDING BLOCK WITH COPOLYMER PE-b-PEG

作     者：Jun-li Shi Hao Li Li-feng Fang Zhi-ying Liang 朱宝库 

作者机构：Department of Polymer Science and Engineering ERC of Membrane and Water Treatment Technology Key Laboratory of Macromolecular Synthesis and Functionalization MOE Zhejiang University 

出 版 物：《Chinese Journal of Polymer Science》 (高分子科学（英文版）)

年 卷 期：2013年第31卷第2期

页      面：309-317页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 20974094  U1134002) 

主　　题：Polyethylene Poly（ethylene-block-ethylene glycol） copolymer Blend porous separator Thermally inducedphase separation Lithium ion battery separator. 

摘      要：To improve the performances of HDPE-based separators, polyether chains were incorporated into HDPE membranes by blending with poly（ethylene-block-ethylene glycol） （PE-b-PEG） via thermally induced phase separation （TIPS） process. By measuring the composition, morphology, crystallinity, ion conductivity, etc, the influence of PE-b-PEG on structures and properties of the blend separator were investigated. It was found that the incorporated PEG chains yielded higher surface energy for HDPE separator and improved affinity to liquid electrolyte. Thus, the stability of liquid electrolyte trapped in separator was increased while the interfacial resistance between separator and electrode was reduced effectively. The ionic conductivity of liquid electrolyte soaked separator could reach 1.28 ×10^-3 ***^-1 at 25℃, and the electrochemical stability window was up to 4.5 V （versus Li^＋/Li）. These results revealed that blending PE-b-PEG into porous HDPE membranes could efficiently improve the performances of PE separators for lithium batteries.