Lithium iron phosphate battery separator materials and their development status and prospects

What is the separator material for lithium iron phosphate batteries? The separators of lithium iron phosphate batteries can be divided into different types according to the structure and composition. There are three common and important ones on the market now, namely porous polymer membranes, non-woven membranes and Inorganic composite membrane. 1. Porous polymer membrane refers to a lithium iron phosphate battery separator with uniform pore distribution prepared by mechanical methods, thermally induced phase separation methods, immersion precipitation methods and other methods. 2. The non-woven fabric separator is composed of oriented or random fibers, and is usually compounded with organic matter or ceramic gel to obtain a lithium battery separator with better chemical and physical properties. 3. Inorganic composite membranes are mostly lithium iron phosphate battery separators that are composited with inorganic nanoparticles and high polymers. Polyolefin materials have excellent mechanical properties, chemical stability and relatively inexpensive characteristics. Therefore, polyolefin microporous membranes such as polyethylene and polypropylene have been used as lithium battery separators in the early stage of lithium battery pack research and development. Although in recent years there have been studies using other materials to prepare lithium battery separators, such as the phase inversion method using polyvinylidene fluoride (PVDF) as the bulk polymer to prepare lithium battery separators, and the study of cellulose composite membranes as lithium battery separator materials. However, so far commercial lithium iron phosphate battery separator materials still mainly use polyethylene and polypropylene microporous membranes. The processing technology of lithium iron phosphate battery diaphragm is complicated and the technical barriers are high. High-performance lithium batteries require the separator to have thickness uniformity and excellent mechanical properties (including tensile strength and puncture resistance), air permeability, and physical and chemical properties (including wettability, chemical stability, thermal stability, and safety). The superiority of the separator directly affects the capacity, cycle capacity and safety performance of lithium batteries. Generally speaking, due to the high unit cost of positive and negative materials in the ternary lithium battery pack, the cost of the separator accounts for less than 10%, and the unit cost of the positive and negative materials in the lithium iron phosphate battery is relatively low, and the cost of the separator accounts for 15%. about. Among lithium battery materials, diaphragm technology barriers and gross profit margins are relatively high, and it is also the last material to achieve localization. The development status and prospects of lithium iron phosphate battery diaphragm materials. my country’s lithium iron phosphate battery diaphragm industry is in a stage of rapid development. Wet diaphragms have gradually become the mainstream technical route. At the same time, the overall technical level of domestic diaphragms and the technical level of international first-line companies are still relatively large. gap. At present, the lithium battery separator market in my country in 2019 can be said to be very bad. One is that the output is severely surplus due to the early state investment policy; the other is the national new energy industry policy, the state subsidies for power vehicles have fallen, and the subsidy requirements have increased. Lithium battery manufacturers have major problems in the capital chain, and lithium battery manufacturers have also put forward new requirements for diaphragm suppliers in terms of price, quality, and billing period. The future direction of the lithium iron phosphate battery separator industry is broad and the development potential is huge. At present, the low-end products of the industry have entered a competitive stage, the company's profits are becoming more and more equal, and the industry integration and market segmentation are about to be completed. In the future, the overall product price of the lithium iron phosphate battery separator industry will further decline, and more product innovations will meet the different needs of downstream industries. 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: How to distinguish between good and bad electric vehicle batteries