Introduction to the differences and characteristics of wet and dry separators for lithium-ion batteries

The difference between dry and wet lithium-ion battery separators. Comparison of the difference between wet and dry lithium-ion battery separators. Diaphragm is the core of lithium-ion battery preparation. Lithium-ion battery diaphragms are generally divided into dry process and wet process according to the process. Therefore, diaphragm products are also divided into dry process and wet process. The many characteristics that lithium-ion battery separators must have, put forward special requirements for their production process, and the production process includes raw material formula and rapid formula adjustment, micropore preparation technology, and independent design of complete equipment. a. Because the process is simple, the investment in fixed assets is smaller than that of the wet method; however, it is difficult to control the temperature and other indicators of the processing technology, and the wet method is simpler; b. The dry method can be used for three-layer film, and the wet method can only do Single-layer film; (The advantage of three-layer film is that the thermal shutdown temperature is 135 degrees, but the thermal stability temperature is 160 degrees, which can prevent thermal inertia, and has a space of 25 degrees, which is safer) c, dry and wet methods in addition to processing technology Different, the raw materials used are also different. The raw materials used in the dry method have good fluidity and low molecular weight, so the high temperature can only reach 135 degrees, and it will shrink when exposed to heat. The safety is not suitable for high-power and high-capacity batteries; the wet method uses non-flowing, high-molecular-weight raw materials. The thermal shutdown temperature can reach 180 degrees, which can ensure the safety of high-power lithium-ion batteries; d. The dry method has advantages in the production of general lithium-ion batteries, with low cost, less pollution and more uniform holes; high-power batteries are wet The law has advantages, the important thing is safety and low heat shrinkage. Advantages of Lithium-ion battery wet-process separators and dry-process separators Lithium-ion battery wet separators are light, thin and not easy to tear, but the melting point of PE is 135℃, which is less safe than dry separators. In addition to the different raw materials and production processes, the overall cost is higher Dry process separator: The dry process separator product has a high melting point, better heat resistance, high pressure resistance, and oxidation resistance, but it is related to the thicker wet process separator and easy vertical tearing, which requires higher process requirements for battery companies. Diaphragm is the link with the highest technical barrier in lithium-ion battery materials, and its performance is very important to the lightweight and safety of lithium-ion batteries. Wet-process diaphragms have certain advantages over dry-process diaphragms in terms of mechanical properties, air permeability, and physical and chemical properties. After coating, the thermal stability of wet-process diaphragms can be greatly improved. In general, wet-coated diaphragms have obvious performance advantages. Most high-end consumer batteries use wet-process separators. With the increase in energy density requirements of power lithium batteries, especially the wide application of ternary batteries, the penetration rate of wet-process separators in power lithium batteries will gradually increase. 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: What is a polymer lithium ion battery?