基于Polymer-S-C/SiO_2多层结构大孔电极锂硫离子电池的制备与性能  

Preparation and performance of lithium-sulfur batteries based on multilayer structure in Polymer-S-C/SiO_2 macroporous electrodes

作　　者：陈宗宗[1] 张瑞丰[1] 

机构地区：[1]宁波大学材料科学与化学工程学院,宁波315211

出　　处：《复合材料学报》2014年第2期525-531,共7页Acta Materiae Compositae Sinica

基　　金：国家"973"计划前期专项(2010CB635116);国家自然科学基金(20674041);宁波大学王宽诚基金

摘　　要：以新型SiO2大孔材料为模板,采用原位聚合及真空热解的方法制备出大孔C/SiO2复合电极,并先后在孔道表面负载单质硫及聚合物膜后得到具有Polymer-S-C/SiO2多层结构的复合大孔电极。用SEM对电极结构进行表征,并测定了比表面积和负载物的平均厚度;用EIS和充放电测试对电极的电化学性能进行了研究。结果表明:聚合物膜厚度的增加可使电极的交流阻抗迅速增大,同时能明显改善锂硫离子电池的逆循环性,说明聚合物膜的存在能够有效抑制多硫化物中间产物的流失。改变单体的用量可以调控聚合物膜的厚度,当聚合物膜平均厚度为8.0nm时,锂离子电池的循环性能达到最佳,其首次放电比容量达792mA·h/g,经过50个循环后,可逆容量仍达到635mA·h/g。The macroporous conducting C/SiO2 composite electrode was prepared in-situ polymerization and vacuum pyrolysis in a novel SiO2 macroporous template,followed by loading the elemental sulfur and the polymer film on the channel surface to obtain the Polymer-S-C/SiO2 composite macroporous electrode with multilayer structure.The structures of Polymer-S-C/SiO2 electrodes were characterized by SEM,and the specific surface area and average thickness of loads were also measured.The electrochemical performances were studied by electrochemical chargedischarge experiments and impedance spectroscopy.The results show that the alternating current impedance of electrode increases rapidly and the reverse cycle performance of lithium ion batteries are improved obviously when the thickness of the polymer film increases,which shows that the existence of the polymer film can effectively inhibit the loss of polysulfide intermediate.The thickness of the polymer film can be adjusted by changing the dosage of the monomer.When the average thickness of the polymer film is 8.0nm,the lithium ion battery exhibits the first discharge specific capacity of 792mA·h/g,and it remains 635mA·h/g after 50cycles,which shows the best effects.

关 键 词：SiO2大孔材料 C/SiO2复合电极 单质硫 聚合物膜 锂硫离子电池 

分 类 号：TB332[一般工业技术—材料科学与工程]