Diaphragm, preparation method thereof and battery

• Main Authors: ZHUANG ZHI, SHAN HUAJING, CHENG YUE, CAO DAWEI, CHEN YONGLE, JIN YING, WANG QI, NING CHAOZONG, SUN MINQIANG
• Format: Patent
• Language: Chinese; English
• Published: 08.08.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention provides a diaphragm, a preparation method thereof and a battery, and belongs to the field of battery diaphragms. The separator comprises a porous substrate and a porous coating layer on at least one surface of the porous substrate, the porous coating layer comprises inorganic particles and a binder polymer, and the binder polymer comprises a first type of polymer and a second type of polymer. The softening points of the first polymer and the second polymer in the diaphragm are different, the first polymer contains a polymer with the softening point of 80-140 DEG C, and the second polymer contains a polymer with the softening point of 40-80 DEG C. In the diaphragm, the first polymer is a fluorine polymer, the second polymer is a non-fluorine polymer, and the non-fluorine polymer is a copolymer containing two or more structural units. In the porous coating of the diaphragm, the inorganic particles can provide good heat resistance for the diaphragm, and the porous coating has good bonding performa