Developed a lithium-ion battery non-woven separator made of nanofibers

Business News, February 28, 　 developed a polyolefin non-woven fabric as the base material, made of PVA (polyvinyl alcohol) nanofiber spun lithium ion rechargeable battery separator (Figure 1). Compared with mainstream polyolefin porous membrane separators, this product can increase the upper limit of the melting temperature and is more heat-resistant. In addition, because the non-woven fabric is used, costs can be easily reduced. The diaphragm has been exhibited at the'nano tech 2012 International Nanotechnology Comprehensive Exhibition and Technology Conference' (held at the Ariake International Convention and Exhibition Center in Tokyo on February 15-17, 2012).　　 If it is a porous film separator made of PE (polyethylene), which is one of the polyolefins, the upper limit of the melting temperature that causes the diaphragm to shrink is usually low, only 130-140°C. The separator developed by Hirose Paper uses PVA, so the upper limit of the melting temperature is higher than 200°C. In addition, according to the company, adding inorganic substances such as silicon (SiO2) to the nanofibers can further increase the upper limit of the melting temperature.　　 PVA nanofibers are made by the electrospinning method (Electrospinning) independently improved by Hirose Paper, with a fiber diameter of about 200nm. The average pore diameter of the membrane woven on the polyolefin substrate is below 500nm and the thickness is only 20-30μm.