Lithium battery separator dry production process

Lithium battery separator dry production process
Dry single drawing process:
1) Feeding: PE or PP and additives and other raw materials are pretreated according to the formula, and then sent to the extrusion system.
2) Casting: The pretreated raw materials are melted and plasticized in the extrusion system, and the melt is extruded from the die, and the melt is cast to form a base film with a specific crystal structure.
3) heat treatment: the base film is heat-treated to obtain a hard elastic film.
4) Stretching: The hard elastic film is subjected to cold stretching and hot stretching to form a nano-microporous film.
5) Slitting: Cut the nano-microporous membrane into finished membranes according to customer specifications.
Dry double drawing process:
1) Feeding: PP and pore forming agent and other raw materials are pretreated according to the formula and then sent to the extrusion system.
2) Casting: to obtain PP casting sheets with high crystal content and good uniformity of β crystal morphology.
3) Longitudinal stretching: Longitudinal stretching is carried out on the cast sheet at a certain temperature, and holes are formed by using the characteristics that crystals are easy to form holes under tensile stress.
4) Transverse stretching: Transverse stretching is performed on the sample at a higher temperature to expand the pores while improving the uniformity of the pore size distribution.