Lithium battery diaphragm production process

Lithium battery diaphragm production process
The production process of lithium battery separator is mainly divided into dry stretching and wet stretching. The many characteristics that lithium battery separators need to possess put forward special requirements for its production process, and the winning production process includes raw material formula and rapid formula adjustment, microporous preparation technology, independent design of complete sets of equipment and other processes.
Lithium battery dry diaphragm technology is the most commonly used method in the diaphragm preparation process. This process is to mix high molecular polymers, additives and other raw materials to form a uniform melt, and form a lamellar structure under tensile stress during extrusion. Heat treatment sheet Crystal structure to obtain a hard and elastic polymer film, then stretched at a certain temperature to form slit-shaped micropores, and then heat-set to obtain a microporous film. At present, the dry process mainly includes two processes of dry uniaxial stretching and biaxial stretching.
Wet production process, also known as phase separation method or thermal phase separation method, wet process mixes liquid hydrocarbons or some small molecular substances with polyolefin resin, heats and melts to form a uniform mixture, and then cools down for phase separation, pressing The membrane is obtained, and then the membrane is heated to a temperature close to the melting point, and the molecular chain is oriented by two-way stretching, and finally kept for a certain period of time, and the residual solvent is eluted with volatile substances, and the interpenetrating microporous membrane material can be prepared.