环糊精改性聚丙烯膜及其在锂硫电池中的应用  

Cyclodextrin Modified Polypropylene Separator and Its Application in Lithium Sulfur Battery

作　　者：姚莹梅 武双林 余彦婷 黄锋林[1] Yingmei Yao;Shuanglin Wu;Yanting Yu;Fenglin Huang(KeyLaboratory of Eco-Textile,Ministry of Education,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学生态纺织教育部重点实验室,江苏无锡214122

出　　处：《高分子材料科学与工程》2022年第1期153-158,共6页Polymer Materials Science & Engineering

基　　金：江苏省重点研发项目(BE2017060);博士后特别资助项目(169483)。

摘　　要：以聚丙烯(PP)为基底膜,利用常温等离子体对其进行亲水性改性,环糊精作为分子筛涂层对其进行修饰,以其作为锂硫电池隔膜,可实现对多硫化物的有效阻碍,提高锂硫电池比容量及循环稳定性。对修饰隔膜的表观形貌、孔隙率、电解液亲和性、对多硫化物扩散的抑制效果,以及在锂硫电池中的电化学性能等进行了表征。结果显示,修饰隔膜的孔隙率达53.79%,高于商业隔膜58.02%。多硫化物扩散实验进一步表明,环糊精分子筛涂层修饰的隔膜可以有效抑制多硫化物的穿梭效应。改性隔膜在0.2C电流密度时,初始放电比容量达1275.89 mAh/g,200次循环后放电比容量达916.69mAh/g,显示出优异的电化学性能。Polypropylene(PP),which was used as substrate membrane,was modified by plasma at room temperature to improve its hydrophilicity.Then cyclodextrin was used as molecular sieve coating on the membrane,as separator of lithium-sulfur battery,the cyclodextrin acted as physical barrier to hamper the movement of polysulfides between the cathode and anode,which could enhance the specific capacity and cycle stability of lithium-sulfur batteries.The morphology,porosity,affinity of electrolyte,diffusion inhibition effect of polysulfides and electrochemical performance of the modified membrane in lithium-sulfur batteries were characterized and studied.The results show that the porosity of modified membrane is 53.79%,which is 58.02% higher than that of commercial PP membrane.Polysulfides diffusion experiments further prove that the membrane modified with cyclodextrin molecular sieve could effectively inhibit the shuttle effect of polysulfides.The initial discharge specific capacity of the modified separator battery is 1275.89 mAh/g at the current density of 0.2 C.And discharge specific capacity is 916.69 mAh/g after 200 cycles.The battery with the cyclodextrin modified PP separator shows excellent electrochemical performance,which provides the possibilities for the development of high-performance lithium-sulfur batteries.

关 键 词：环糊精分子筛 聚丙烯 锂硫电池隔膜 多硫化物 

分 类 号：TM912[电气工程—电力电子与电力传动]