Lithium ion battery high-end membrane technology is a core threshold

Lithium ion battery separator technology is a core threshold. The lithium ion battery end diaphragm technology deeply reflects the characteristics of current diaphragm technology. It is reported that the membrane is currently a high value-added material in the technical barrier of lithium battery materials, accounting for about 15% of the cost of lithium ion batteries. Its technical difficulties lie in the engineering technology of pore formation, substrate materials, and manufacturing equipment. Due to its technical complexity, the impact on power lithium ion batteries is even greater.

Lithium ion battery separator technology is a core threshold

Lithium ion battery separator technology is currently a pain point in China's power battery industry. Among lithium battery materials, positive and negative electrode materials and electrolytes have basically been localized, while separators have started relatively late and domestic enterprises have not achieved high technological maturity. Although the localization rate of lithium-ion battery separators in China has been continuously increasing in recent years, it mainly occupies the low-end 3C battery separator market, and the localization rate of separators is still very low. 3C batteries and separators for power batteries still rely heavily on imports.

Currently, the common problems of domestic membranes are poor consistency, mainly due to irregular defects, substandard porosity, and uneven thickness, pore distribution, and pore size distribution. Membrane technology has a fairly high threshold, requiring not only a huge investment, but also a strong research and development and processing team, skilled process technology, and high-level processing lines, which can be broken in a short time.

The research on basic materials for lithium ion batteries in China still lags behind the world level, especially as battery separator materials still rely on imports. From an industry perspective, the United States still has original innovation and core material research and development for lithium ion batteries; As a major manufacturer of battery materials, Japan has strict processing standards and is able to manufacture new finished batteries; As the second tier, China and South Korea are in a follow-up state. Compared to Japan and South Korea, China's low-end lithium ion battery products have more advantages, but there are still significant gaps in some products, especially in core materials and manufacturing processes related to battery safety.

Fortunately, domestic enterprises such as Zhongke Technology and Xingyuan Materials have made significant breakthroughs in lithium-ion battery separator technology. I believe that in the near future, China's power lithium-ion battery industry will be able to break foreign technological monopolies and take the initiative in its own hands.

Domestic technology of lithium ion battery separator has been broken through

The new type of membrane is a ceramic functional membrane, which uses substrate membrane surface solution technology and inorganic ceramic powder dispersion technology to optimize the coating effect of ceramic powder, establish a dose effect relationship between coating thickness, ceramic type, particle size, surface characteristics, and battery performance, and summarize the variation rules of technical parameters of the ceramic membrane. The developed membrane has both current cutoff characteristics and high heat resistance performance, and its technical indicators have reached the world's advanced level. Not only for ordinary lithium batteries, but also for monomer polymer lithium ion batteries, the requirements for high consistency can be met. The polyethylene membrane coated with aluminum oxide with a thickness of 3 microns has a thermal shrinkage of less than 2% for 2 hours at 150 ℃, and its performance is superior to similar foreign products.

AVIC Lithium Battery Diaphragm Project has completed an experimental line with an annual output of 3 million square meters of ceramic functional diaphragms. On this basis, it has completed the development of curing, sizing, coating, and cutting processes to form processing capabilities. It has also conducted the design, trial production, and detection of ceramic membrane batteries, which is crucial to improving the safety of the processing and use of lithium ion power batteries. Given the high price of crude oil and the serious atmospheric pollution caused by exhaust emissions in China, the promotion and use of new energy vehicles is undoubtedly positive energy.