倒相法制备PVDF-HFP基复合微孔聚合物电解质

PVDF-HFP matrix complex micro-porous polymer electrolyte prepared by phase inversion method

摘要:

为改善纳米粒子在聚合物电解质中的分散效果,采用倒相制膜法,以纳米SiO₂为填料,以OP-10为分散剂,制备复合微孔聚偏氟乙烯-六氟丙烯基电解质PVDF-HFP-SiO₂(OP-10)．用SEM、XRD、交流阻抗法等测试手段对电解质的微观形貌、内部结构和电化学相关性能等进行表征,结果表明:SiO₂的加入降低了聚合物电解质膜的结晶度,增强了电解质的拉伸强度,提高了PVDF-HFP-SiO₂(OP-10)聚合物电解质的电导率,在20 ℃时,可达到490×10-3 S·cm-1,电化学稳定窗口为53 V,电解质的离子迁移数为083．分散剂OP-10的加入改善了纳米SiO₂与基质的界面相容性,改善了SiO₂在基质中的分散度．

Abstract:

To improve the distribution properties of nanoparticles in the polymer electrolyte, micro-porous polymer electrolyte PVDF-HFP-SiO₂(OP-10) was prepared with phase inversion method by adopting nano-sized SiO₂ as the inorganic filler and OP-10 as dispersant. The morphology, crystal structure and electrochemical properties of the electrolyte were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), electrochemical impedance spectra (EIS). The results showed that the addition of nano-SiO₂ suppressed the crystallinity of polymer electrolyte and enhanced the tensile intensity. The ionic conductivity was improved, the highest ionic conductivity (20 ℃） of the PVDF-HFP-SiO₂(OP-10) polymer electrolyte was 490×10-3S·cm-1,with a high electrochemical stability window of 53 V, and the corresponding cation transference number was 083. The distribution of SiO₂ and interfacial compatibility of nanometer particles were improved by the addition of OP-10.