Electrospun Silicon Dioxide/poly(vinylidene fluoride) Nanofibrous Membrane Comprising a Skin Multicore-Shell Nanostructure as a New High-Heat-Resistant Separator for Lithium-Ion Polymer Batteries

• Published in: Polymers 2024-06, Vol.16 (13), p.1810
• Main Authors: Kim, Young-Gon, Jeong, Bo Gyeong, Park, Bum Jin, Kim, Heejin, Lee, Min Wook, Jo, Seong Mu
• Format: Article
• Language: English
• Subjects: Ceramic glazes; Electric vehicles; Electrolytes; Electrospinning; Fluorides; Lithium; Lithium ions; Mechanical properties; Membranes; Morphology; Open circuit voltage; Polymers; Polyolefins; Polyvinylidene fluorides; Porous silicon; Protective coatings; Rechargeable batteries; Scanning electron microscopy; Silica; Silicon dioxide; Skin; Skin resistance; Sol-gel processes; Spectrum analysis; Temperature; Thickness; Vinylidene fluoride
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym16131810

Porous silicon dioxide (SiO )/poly(vinylidene fluoride) (PVdF), SiO /PVdF, and fibrous composite membranes were prepared by electrospinning a blend solution of a SiO sol-gel/PVdF. The nanofibers of the SiO /PVdF (3/7 wt. ratio) blend comprised skin and nanofibrillar structures which were obtained from the SiO component. The thickness of the SiO skin layer comprising a thin skin layer could be readily tuned depending on the weight proportions of SiO and PVdF. The composite membrane exhibited a low thermal shrinkage of ~3% for 2 h at 200 °C. In the prototype cell comprising the composite membrane, the alternating current impedance increased rapidly at ~225 °C, and the open-circuit voltage steeply decreased at ~170 °C, almost becoming 0 V at ~180 °C. After being exposed at temperatures of >270 °C, its three-dimensional network structure was maintained without the closure of the pore structure by a melt-down of the membrane.