144 / 2018-08-25 14:15:15

Study on the Energy Storage Perfomance of Amorphous-Al2O3 /PVDF Nanocomposite Film Based on Sol Blending Doping Strategy

PVDF, composite films, interfacial polarization, energy storage

In this study, a doping strategy of directly blending inorganic sol with organosol has been proposed for solving the bottleneck problem caused by uneven distribution of inorganic filled phase in the matrix. In this study, inorganic alumina (Al2O3) sol and polyvinylidene fluoride (PVDF) sol were solution-solved by sol-gel method, and then flexible amorphous-Al2O3/PVDF nanocomposite film was prepared by solution casting process. It can be found that the dielectric constant of Al2O3/PVDF nanocomposite film (the dielectric constant of the nanocomposite film is 14 when the mass fraction of Al2O3 is 10 wt.%) is higher than that of pure PVDF composite film (~11). At the same time, the discharge energy density of the Al2O3/PVDF nanocomposite film also shows improvement with the increase of the mass fraction. For example, when the mass fraction of Al2O3 is 7.5wt.%, the discharge energy density of the nanocomposite film is up to 14 J/cm3 at an electric field strength of 470 kV/mm, which is higher than that of a pure PVDF nanocomposite film (the maximum energy density is 5 J/cm3 at an electric field strength of 260 kV/mm). The results in this study indicate that the sol blending doping strategy may be expected to an effective way for improving the structural characteristics and electrical performances of the polymer-based energy storage dielectrics.