What is the basic process flow of lithium battery dry separator?

The current dry process mainly includes two processes: dry uniaxial stretching and biaxial stretching. The dry single drawing process is as follows: 1. Feeding: raw materials such as PE or PP and additives are pretreated according to the formula and then transported to the extrusion system. 2. Casting: The pretreated raw material is melted and plasticized in the extrusion system, and then the melt is extruded from the die, and the melt is cast to form a base film with a specific crystalline structure. 3. Heat treatment: the base film is heat treated to obtain a hard elastic film. 4. Stretching: Cold stretch and hot stretch the hard elastic film to form a nanoporous film. 5. Slitting: Cut the nano-microporous membrane into finished membranes according to customer specifications. Feeding: raw materials such as PP and pore former are pretreated according to the formula and then transported to the extrusion system. Casting: A PP cast sheet with high β crystal content and good β crystal morphology uniformity is obtained. Longitudinal stretching: The cast piece is stretched longitudinally at a certain temperature, and the β crystal is easy to form pores under tensile stress to create pores. Lateral stretch: the sample is stretched laterally at a higher temperature to expand the pores and at the same time improve the uniformity of the pore size distribution. Shaping and rewinding: Heat treatment of the diaphragm at high temperature to reduce its thermal shrinkage and improve dimensional stability. The dry process of lithium battery diaphragm is the most commonly used method in the process of diaphragm preparation. The process is to mix high molecular polymers, additives and other raw materials to form a uniform melt, and form a lamella structure under tensile stress during extrusion. The crystalline structure obtains a hard and elastic polymer film, which is then stretched at a certain temperature to form slit-like micropores, and after heat setting, a microporous film is prepared. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: What types and uses are there for lithium batteries?