The stand or fall of lithium battery diaphragm different production process

Since the advent of lithium ion battery, popular, now in the scope of its application gradually expanded, familiar with lithium battery structure principle of the person all know, the merits of the diaphragm for performance of lithium battery has played a vital role, but the battery diaphragm production process there are many and very complex, dry method and wet method, which technology is more mature? What kind of technology more has the potential to contribute to the future development of lithium battery? The lithium ion battery diaphragm industry in China white paper ( 2015). 'In detailed study the global and Chinese industries and enterprises on the basis of diaphragm, points out the future of diaphragm industry competition will focus on the wet diaphragm product competition. In the field of wet membrane, the current domestic is still in the early of import substitution, the paper from the enterprise overall level of scale, product and technology ability and growth potential, team and channel construction and so on several dimensions of domestic production enterprises mainly wet diaphragm ranked, eventually becoming the diaphragm to comprehensive score 3. Eight points and ranked first in its products and technology level, the ability of team and channel construction such as single indicators rank, is considered to be the most potential for China's future enterprise wet diaphragm. White paper in the field of dry diaphragm, think the current basic dry diaphragm is relatively mature, is the competition is more intense than the level of wet method, and can completely replace the imported diaphragm, facing downward pressure on prices. Also, from the overall size of enterprises, product and technology level, the white paper, team and channel construction ability and growth potential and so on several dimensions of domestic main dry diaphragm enterprises ranked, star source material with composite scores 4 finally. Eight points and ranked first in its products and technology level, the ability of team and channel construction such as single indicators rank, is considered to be the most potential for China's future dry diaphragm enterprises. White paper also points out that the current domestic most dry diaphragm enterprises are also actively invest in the construction of wet membrane production line, and some businesses such as star source material with dry process and wet process production line. Lithium battery diaphragm production process including wet process and dry process, at the same time can be divided into the uniaxial tensile process and dry process two-way tensile process. Wet wet process diaphragm liquid hydrocarbon or small molecular substances mixed with polyolefin resin, after melting, heating to form homogeneous mixture, then cooling phase separation, the suppression of diaphragm, then heated to near melting point temperature of diaphragm, and two-way stretch molecule chain orientation, the heat preservation time, elution residue solvent with volatile substances, each other can be prepared through the microporous membrane material. Japan agms, Japan east, South Korea SK, adopt this technology. Application: apply to high performance lithium ion battery, etc. Dry dry diaphragm can be subdivided into uniaxial tensile process and bidirectional tensile process. Dry uniaxial tensile process is through the production of hard elastic fiber, the method of preparation of the low degree of crystallinity of polypropylene or polyethylene film high orientation, high temperature annealing obtain high crystallinity, orientation film again. The film stretch forming micro defects in low temperature first, then make the defect in the heat, forming pores. The United States, Japan celgard ube XingChan etc. Adopting this technology. Dry two-way stretch technology institute of chemistry, Chinese Academy of Sciences in the early 1990 s is developed with independent intellectual property rights technology. By joining in the polypropylene has nucleation effect of beta crystal improver, using polypropylene density differences between different phase, in the process of drawing forming microporous crystal shape changes, for the production of single PP membrane. China is now more than one-third capacity use dry dual pull technology, products in the low-end market occupy larger proportion. Application: apply to large lithium ion power battery ( Electric cars, electric motorcycles, electric tools, large-scale energy storage equipment, military industry with large batteries) Battery diaphragm technology is already mature, both dry and wet manufacturing battery diaphragm, lam jan 400 - shenzhen 6666 - 322 can well meet the needs of different field products.