Effect on properties of PVDF-HFP based composite polymer electrolyte doped with nano-SiO2

作者：Li, Yan; Li, Xinhai^*; Guo, Huajun; Wang, Zhixing; Li, Tao

来源：Iranian Polymer Journal, 2014, 23(6): 487-494.

DOI：10.1007/s13726-014-0244-9

• PVDF-HFP
• Composite polymer electrolyte
• Nano-SiO2
• Lithium ion battery

Various kinds of nano-SiO2 using different catalysts were obtained and characterized by scanning electron microscope (SEM) technique. The results showed that the nano-SiO2 using NH3 center dot H2O as catalyst presented the best morphology. Poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) based composite polymer electrolyte (CPE) membranes doped with different contents of nano-SiO2 were prepared by phase inversion method. The as-prepared CPE membranes were immersed into 1.0 M LiPF6-EC/DMC/EMC electrolytes for 0.5 h to be activated. The physicochemical and electrochemical properties of the CPEs were characterized by SEM, X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV) techniques. The results indicate that the CPEs doped with 10 % nano-SiO2 exhibit the best performance. SEM micrographs showed that the CPE membranes have uniform surface with abundant interconnected micro-pores, and the uptake ratio was up to 104.4 wt%. EIS and LSV analysis also showed that the ionic conductivity at room temperature and electrochemical stability window of the modified membrane can reach 3.372 mS cm(-1) and 4.7 V, respectively. The interfacial resistance R-i was 670 Omega cm(-2) in the first day, then increased to a stable value of about 850 Omega cm(-2) in 10 days storage at room temperature. The Li/As-fabricated CPEs/LiCoO2 cell also showed good charge-discharge performance, which suggested that the prepared CPE membranes can be used as potential electrolytes for lithium ion batteries.

• 出版日期2014-6
• 单位中南大学