Functional lithiophilic polymer modified separator for dendrite-free and pulverization-free lithium metal batteries  

作　　者：Lingdi Shen Xin Liu Jing Dong Yuting Zhang Chunxian Xu Chao Lai Shanqing Zhang 

机构地区：[1]School of Chemistry and Materials Science,Jiangsu Normal University,Xuzhou 221116,Jiangsu,China [2]Center for Clean Environment and energy,School of Environment and Science,Griffith University,Queensland 4222,Australia

出　　处：《Journal of Energy Chemistry》2021年第1期262-268,I0009,共8页能源化学（英文版）

基　　金：supported by the Natural Science Foundation of Jiangsu Province (BK20170237);National Natural Science Foundation of China (21808094 and 51871113);Key Research and Development Program of Xuzhou (KC17004);Startup Funding for Introduced Talents of Jiangsu Normal University (16XLR015)。

摘　　要：Severe performance drop and fire risk due to the uneven lithium(Li) dendrite formation and growth during charge/discharge process has been considered as the major obstacle to the practical application of Li metal batteries.So inhibiting dendrite growth and producing a stable and robust solid electrolyte interface(SEI) layer are essential to enable the use of Li metal anodes.In this work,a functional lithiophilic polymer composed of chitosan(CTS),polyethylene oxide(PEO),and poly(triethylene glycol dimethacrylate)(PTEGDMA),was homogeneously deposited on a commercial Celgard separator by combining electrospraying and polymer photopolymerization techniques.The lithiophilic environment offered by the CTS-PEO-PTEGDMA layer enables uniform Li deposition and facilitates the formation of a robust homogeneous SEI layer,thus prevent the formation and growth of Li dendrites.As a result,both Li/Li symmetric cells and LiFePO4/Li full cells deliver significantly enhanced electrochemical performance and cycle life.Even after 1000 cycles,the specific capacity of the modified full cell could be maintained at65.8 mAh g^(-1), twice which of the unmodified cell(32.8 mAh g^(-1)).The long-term cycling stability in Li/Li symmetric cells,dendrite-free anodes in SEM images and XPS analysis suggest that the pulverization of the Li anode was effectively suppressed by the lithiophilic polymer layer.

关 键 词：Lithium metal batteries Functional separators Anode protection Solid electrolyte interface Long cycling life 

分 类 号：TM912[电气工程—电力电子与电力传动] TB383.2[一般工业技术—材料科学与工程]