PEO基固态聚合物电解质膜的静电纺丝制备及性能

Preparation and properties of solid polymer electrolyte membranes based on PEO by electrospinning

PEO基固态聚合物电解质被认为是目前固态锂电池领域极具产业化前景的固态电解质。为适应工业化生产,采用静电纺丝技术制备PEO/LiClO_(4)固态聚合物电解质(SPE),研究纺丝电压、纺丝液质量浓度和锂盐含量对SPE纤维膜形貌和直径的影响。通过扫描电子显微镜观察SPE中纤维的形貌,利用Image J软件分析SPE纤维的直径。通过DSC,XRD,FTIR-ATR和拉伸测试等手段对静电纺丝制备的SPE纤维膜的组成、结构、性能等进行研究。结果表明:当纺丝电压为15 kV、PEO/LiClO_(4)纺丝液质量浓度为6%、[EO]∶[Li^(+)]=10∶1(摩尔比)时,静电纺丝方法制备的PEO/LiClO_(4) SPE纤维膜具有较好的纤维形貌,平均直径为557 nm,分布均一;当[EO]∶[Li^(+)]=10∶1时,SPE纤维膜中PEO的熔点仅为53.8℃,结晶度低至18.9%;电解质在30℃时的离子电导率达到5.16×10^(-5)S·cm^(-1),同时具备良好的电化学稳定性和界面稳定性。

PEO-based solid polymer electrolytes are considered as a promising solid electrolyte in the field of solid-state lithium batteries.PEO/LiClO_(4) solid polymer electrolyte(SPE)was prepared through electrostatic spinning technology,in order to meet the demand of industrial production.The effects of spinning voltage,spinning solution concentration and lithium salt content on the morphology and diameter of the fiber were studied.The morphology of SPE fiber was observed by scanning electron microscope and the diameter of SPE fiber was analysed by Image J.Furthermore,the composition,structure and properties of solid polymer electrolyte fiber membranes prepared by electrospinning were studied by DSC,XRD,FTIR-ATR and tensile testing.The results show that the PEO/LiClO_(4) solid polymer electrolyte membrane prepared by electrostatic spinning method has good fiber morphology,when the spinning voltage is 15 kV,and the concentration of PEO/LiClO_(4) spinning solution is 6%,and the molar ratio([EO]∶[Li^(+)])is 10∶1.Meanwhile,the average diameter of the fibers is 557 nm,giving relatively uniform distribution.When[EO]∶[Li^(+)]=10∶1,the melting point of PEO in the SPE fiber membrane is only 53.8℃,with the crystallinity as low as 18.9%.And the ionic conductivity of the prepared SPE exhibits as high as 5.16×10^(-5)S·cm^(-1)at 30℃.Moreover,the prepared electrospun SPE has good electrochemical stability and interfacial stability.