树枝状磺化聚醚砜纤维基复合固态电解质的制备及其性能  

Preparation and application properties of dendritic sulfonated polyethersulfone fiber based composite solid electrolyte

作　　者：杨琪[1,2] 邓南平[1,2] 程博闻[2] 康卫民[1,2] YANG Qi;DENG Nanping;CHENG Bowen;KANG Weimin(School of Textile Science and Engineering,Tiangong University,Tianjin 300387,China;State Key Laboratory of Separation Membranes and Membrane Processes,Tiangong University,Tianjin 300387,China)

机构地区：[1]天津工业大学纺织科学与工程学院,天津300387 [2]天津工业大学分离膜与膜过程国家重点实验室,天津300387

出　　处：《纺织学报》2024年第3期1-10,共10页Journal of Textile Research

基　　金：国家自然科学基金项目(51973157);天津市科技计划项目(19PTSYJC00010)。

摘　　要：为解决应用于全固态锂金属电池中固态有机电解质离子电导率较低和力学性能较弱的问题,采用静电纺丝技术制备了树枝状磺化聚醚砜(SPES)纳米纤维膜,将其与聚氧化乙烯(PEO)结合制备复合固态电解质,并应用于全固态锂金属电池中。探讨了纺丝工艺对纳米纤维形貌的影响,在最佳的静电纺丝工艺参数下,研究了SPES纳米纤维膜对复合固态电解质结晶度、离子电导率、力学性能以及电化学性能的影响。结果表明:在四丁基六氟磷酸铵质量分数为2%,静电纺丝电压为30 kV,接收距离为15 cm时,制备的树枝状SPES纳米纤维膜具有最好的形貌,将PEO浇筑在该纳米纤维膜上获得的复合固态电解质其离子电导率为8.13×10^(-5)S/cm(30℃),断裂强度为5.1 MPa,且可使对称电池在0.1 mA·h/cm^(2)下稳定循环198 h,使LiFePO_(4)/Li电池在循环400圈后仍保持着128.6 mA·h/g的放电比容量;SPES纳米纤维膜因破坏PEO的结晶区且能构成三维离子传输路径,不仅提高了复合固态电解质的离子电导率,还使复合固态电解质具有优异的力学强度,可满足高性能全固态锂金属电池的应用需求。Objective The conventional liquid electrolyte is easy to leak and flammable,which brings potential safety risks to the actual application of lithium metal batteries.Replacing liquid electrolyte with all-solid-state electrolyte has become one of the most feasible methods.However,solid polymer electrolytes are limited by low ionic conductivity and poor mechanical strength.For solving the two problems of solid polymer electrolyte at the same time,nanofiber membranes with high strength are used for modification.Method Dendritic sulfonated polyethersulfone nanofibers(SPES)were prepared by electrospinning technology.They were introduced into polyethylene oxide(PEO)to prepare composite solid electrolytes and applied in high-performance all-solid-state lithium metal batteries.The influences of spinning solution concentration,salt addition,electrospinning voltage and receiving distance on fiber morphologies were explored and analyzed.Moreover,the influences of SPES nanofiber membrane on the crystallinity,ionic conductivity,mechanical properties,and electrochemical properties of composite solid electrolyte were also studied under the optimal spinning process.Results When the spinning solution concentration was 23%,the electrospinning voltage was 30 kV and the receiving distance was 15 cm,the obtained SPES nanofibers had the best morphology among them.Based on obtaining the optimal spinning solution concentration of ordinary SPES nanofibers at 23%,the influence of ammonium tetrabutyl hexafluorophosphate on fiber morphologies were investigated.It was found that the optimum parameters for preparing dendritic SPES nanofibers were salt dosage of 2%,electrospinning voltage of 30 kV and receiving distance of 15 cm.After the nanofibers and PEO were constructed into the composite electrolytes,both the ordinary SPES nanofibers and the dendritic SPES nanofibers caused the crystallization peak of PEO in the composite electrolyte be smaller than that of pure PEO electrolyte,indicating that the interlaced nanofibers were conducive to de

关 键 词：复合固态电解质 锂金属电池 静电纺丝 磺化聚醚砜纤维 聚氧化乙烯 纳米纤维 

分 类 号：TM911[电气工程—电力电子与电力传动] O646[理学—物理化学] TQ152[理学—化学]