Preparation method of lithium battery diaphragm

• Main Authors: FANG TAN, ZHU YONGQIAN, GUO CHAO, QIU XINGFU, CHEN LIXIN
• Format: Patent
• Language: Chinese; English
• Published: 01.10.2021
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention discloses a preparation method of a lithium battery diaphragm. The preparation method comprises the following steps: (1) adding an organic polymer base material, which is polyolefin, into an organic solvent, and conducting stirring to fully mix the organic polymer base material in the organic solvent so as to obtain a first colloidal solution; (2) adding an inorganic material, which is one or a mixture of more than two selected from aluminum oxide, aluminum nitride, aluminum silicate, sodium silicate and boehmite, into the first colloidal solution, and carrying out uniform mixing, stirring and ball-milling to obtain a mixture; (3) heating the mixture to a fluid state, pouring and casting the fluid-state mixture onto a stainless steel substrate, and carrying out cooling to form a diaphragm; (4) carrying out heat treatment on the diaphragm; (5) longitudinally and transversely stretching the diaphragm having been subjected to heat treatment, and locally breaking the joint of an organic polymer and