Polyethylene porous microsphere coated coaxial fiber composite membrane for high safety lithium‐ion battery

• DOI: 10.1002/app.52184
• Publication Date: 2022-01-26T13:41:22Z
• Authors: Xu Wang; Weiwei Cui; Zeyu Lin; Jingxian Piao; Xinyu Qu; Wei Deng; Guifen Gong
• Keywords: Polyetherimide; Thermal Stability; Polyvinylidene fluoride

Abstract A polyetherimide/polyvinylidene fluoride (PEI/PVDF) coaxial fiber membrane coated with polyethylene (PE) porous microspheres thermal shutdown function was prepared. The PE created by the suspension dispersion method are composed of a large number pleated petal structures, which contain abundant pore structures and have melting point 108°C. Ionic conductivity test, scanning electron microscope open circuit voltage cycle performance test show that composite layer can effectively close structure at 110°C stop battery reaction. stability shows does not shrink 210°C, temperature window is as high 100°C, coating significantly improve dimensional membrane. Thanks to microstructure good electrolyte affinity PVDF skin layer, has wetting uptake capabilities. assembled capacity retention rate 88.6% after 100 cycles 0.5 C excellent C‐rate capability.