The role of high-purity alumina for lithium battery separator
High purity nano-alumina can be used for the coating of lithium batteries due to its insulation, thermal insulation and high temperature resistance properties. A nano-alumina coating is applied to the diaphragm of lithium batteries to avoid short circuits between electrodes. Improve the safety of lithium batteries. In recent years, with the increase in production and sales of new energy vehicles, the demand for lithium-ion battery materials has further increased. The production of lithium-ion battery separators basically depends on the production and sales of downstream lithium-ion batteries, and the future growth of lithium-ion batteries will mainly come from new energy vehicles and energy storage.
High purity nano-alumina materials also have excellent flame retardancy. This is because high-purity alumina materials are inherently good flame retardants. Even if the temperature is too high and reaches the zero point of combustion, the material has good flame retardancy. The properties will prevent large-scale combustion and even explosions.
During the operation of a lithium-ion battery, the role of the spacer is to allow lithium ions to pass through the microscopic holes in the spacer, thus completing the charging and discharging process of the battery while keeping the positive and negative electrodes in contact and isolated. The electrons are prevented from passing through. The microporous structure of the diaphragm is therefore very important for the safety performance of the battery. When the cell is overcharged or the internal temperature is too high, the diaphragm pores are closed and the cell is cut off to restrict the movement of ions, thus preventing temperature-induced explosions and other hazards. However, once the temperature reaches the melting temperature of the diaphragm substrate, the diaphragm will completely melt and shrink, the internal circuitry of the cell will be disconnected and the temperature will rise, leading to cell disintegration or even an explosion. Due to its high temperature resistance, safety and self-shutdown properties, coating the surface of the diaphragm with high purity ultra-fine alumina can effectively prevent the diaphragm from melting and the battery from disconnecting due to high temperatures. Therefore, high purity ultra-fine alumina is an ideal material for lithium-ion battery diaphragm coatings, which are currently mainly used for wet lithium battery diaphragm coatings.
