METHOD OF FORMING A FILM MADE OF A FLUOROPOLYMER OF THE POLYVINYLIDENE FLUORIDE TYPE THAT CAN BE USED AS A SEPARATOR FOR A LITHIUM BATTERY

摘要

A film made of a fluorinated polymer of the polyvinylidene fluoride type having suitable properties for use as a lithium storage battery separator is produced using a phase inversion technique in which a solution containing the fluorinated polymer is brought into the presence of an atmosphere laden with water vapor to precipitate the fluorinated polymer. The fluorinated polymer can be precipitated by placing the support on which the solution is deposited, in which the fluorinated polymer has been previously dissolved, in an enclosure containing an atmosphere laden with water vapor and thermostatically regulated to a temperature comprised between 30° C. and 70° C. The relative humidity content during precipitation of the fluorinated polymer is advantageously between about 60% and about 98%.