poly (vinylidene fluoride) (PVDF) and vinylidene fluoride ( VDF ) / trifluoroethylene ( TrFE) copolymers are of considerable current interest for their great ferroelectric and piezoelectric properties. Recently

modified by physical or chemical process

PVDF based fluoro polymer exhibits excellent dielectric and energy storage properties

which is highly expected to be applied in the field of high energy density discharge capacitors. The fluoro polymer with optimized composition treated by the extrusion and subsequent stretching methods possess high dielectric constant ( 12 ~ 60) and very high breakdown electric field. The highest energy storage density is more than 25J/cm

3

( 600 ~ 700MV/m) at room temperature

which is significantly improved of energy density over traditional capacitor dielectric film materials. The recent development of these high performance polymers as dielectric and energy storage materials is summarized in this article.