Advances in Lithium Battery Separators -Lithium - Ion Battery Equipment

The Ministry of Science and Technology's 863 plan energy storage battery major project, supported by the Chinese Academy of Sciences, Shandong Province Outstanding Youth Fund and other research projects, the bionic energy and energy storage system team of Qingdao Institute of Bioenergy and Process Research, Chinese Academy of Sciences, after more than 3 years of scientific research, has made breakthroughs in the field of power lithium-ion battery separators, successfully developed a power lithium-ion battery separator with independent intellectual property rights of high-safety flame-retardant biomass composite materials, and reached the scale of pilot production. The separator is a key component of the power lithium-ion battery. It plays an important role in blocking the electronic conductance of the positive and negative electrodes in the battery, allowing ions to pass through freely to achieve ion conduction. It is also a decisive factor affecting battery capacity, cycle life and safety performance. At present, the mainstream products of commercial lithium-ion battery separators are mechanically stretched polyethylene (PE), polypropylene (PP) microporous films and polypropylene/polyethylene/polypropylene (PP/PE/PP) three-layer microporous composite membranes. The core technology is monopolized by large foreign companies. Commercial polyolefin separators have low porosity, poor transverse tensile strength, liquid retention and thermal stability, which cannot fully meet the requirements of rapid charging and discharging of batteries, and there are great safety hazards.(Lithium - Ion Battery Equipment)

Cellulose is derived from natural plants, has good thermal stability, abundant yield, low price, and is green and sustainable. It is a biomass polymer material with great added value and development prospects. Qingdao Energy uses biomass cellulose as raw material, adopts melt-blown-wet coupling technology with independent intellectual property rights, develops related production and processing equipment, and develops a high-safety and low-cost biomass composite diaphragm. The separator has good electrolyte wetting performance, heat resistance and flame retardancy, and its battery rate and cycle performance are far superior to commercial polyolefin separators.

Relevant domestic experts spoke highly of the biomass composite diaphragm developed by the team, believing it to be a brand-new material system and process method. The successful development of this type of product will fill the domestic gap and provide important technical support for the development of the blue economy in Shandong Province and the blue Silicon Valley in Qingdao. According to researcher Cui Guanglei, the leader of the team, the improvement of self-developed equipment and process optimization will be completed before the end of the year, and it is expected that an annual production capacity of 300,000 square meters will be formed next year.