Our lithium battery research and development status quo of the diaphragm

Source: 2020 - 03 - Hits: 23 struck time our lithium battery research and development status quo of the diaphragm in the interview, battery materials experts told reporters that the diaphragm is one of the important part of lithium batteries, the main material of the diaphragm is porous polymer film, including polyethylene and polypropylene. Lithium battery diaphragm on security, permeability, porosity and thickness have strict requirements. 'in lithium-ion batteries, charged ions move continuously formed between the positive and negative current, the electrodes and the diaphragm between the positive and negative electrode of battery, which not only can prevent the direct contact between the positive and negative electrodes, and ensure smooth through the electrolyte ions'. Zhou zhen vividly explained, battery electrolyte is like a river, the river trekking ship such as lithium ion diaphragm is based on the waist of the dam, a diaphragm gate hole like a dam, under normal circumstances, ion continuous flow in positive and negative poles of the end of the cycle of charging and discharging. High-end diaphragm usually adopt ceramic material. If the electrolyte temperature is too high, the material will swell, stomatal would like door closed, and block of ion exchange, so as to prevent the battery due to high temperature burst. 'Zhou Zhen said, the diaphragm is lithium battery money speculation to the highest technical barriers of a material, its technical difficulty lies in the hole of engineering technology, matrix materials and manufacturing equipment. 'technical requirement is high, so the price is high, accounting for more than 10% of the total cost of the battery. 'at the moment, the world's best lithium battery diaphragm materials from asahi chemical and eastern chemical two Japanese companies, and domestic lithium battery membrane with a 90% share of the market for aluminium is exclusive to showa denko and other Japanese manufacturers. Tianjin lishen company engineer, told reporters that compared with Japan, China's high-end diaphragm distance is obvious. Domestic diaphragm the consistency of the product is not high, the unqualified porosity, thickness, pore dispersion degree and aperture dispersion degree of inequality. Diaphragm directly affects the quality of the battery capacity, charging and discharging cycle life, flame retardant and antiknock safety features. The personage inside course of study sighed regretfully: 'a layer of the diaphragm grime, stride is a sunny day! 'domestic diaphragm to break now, lithium-ion battery diaphragm manufacturing process is mainly divided into wet and dry. The reporter understands in the interview, the first party on the dry process in our country has entered the international, but in the field of wet membrane, although domestic companies mastered the method, but still all compete with foreign giants, in addition, the center of production equipment is mainly rely on imports. Figures show that in 2017, nearly 113 billion yuan RMB, the domestic lithium battery market planning power lithium battery planning of about 60 billion yuan. Promulgated by the Ministry of Industry and Information Technology, energy conservation and new energy car industry development planning ( 2011 - 2020) 'Also shows that by 2020, a year in China can only produce 2 million all-electric cars and plug-in hybrids. According to battery professional association of the budget, annual demand for high quality auto power battery diaphragm materials will reach hundreds of millions of square meters. 'the development of lithium battery can't be controlled, the diaphragm and other high-end material also can't escape! 'Wu Mengtao think mo co. , LTD. , general manager of tianjin, such a huge market demand, entirely dependent on foreign manufacturers, not only unrealistic, but also will be one of the largest power lithium batteries. High-end diaphragm technology has high threshold, not only need to spend a lot of money, also need to have a strong r &d and production team, skilled technology and a high level of production line. 'for wet manufacture, resin material and additive of extrusion process and mixing process and stretching are two core difficulties. 'zhou zhen think diaphragm domestic enterprises want more, it is necessary to base material surface treatment technology, such as tensile adhesive technology, materials, equipment and process control of stamping products, and other areas of the three' lessons', in addition, the diaphragm industrial chain upstream, including domestic coating machine and so on, the production center is equipped with also needs to catch up, as soon as possible to complete the localization greater breakthrough.