Structure, porosity and conductivity of PVdF films for polymer electrolytes

Semicrystalline porous films of poly(vinylidenefluoride) (PVdF) were prepared by a phase-inversion method. The microstructure of the films depends on the preparation conditions, and can be classified in two categories: sponge-like and finger-like. Porosities higher than 75% can be reached with finger-like texture, and all the pore structure is accessible to the electrolyte solution. Conductivity higher than 2 mS/cm is easily obtained by soaking the films into standard electrolyte solutions.