Robust polyetherimide fibrous membrane with crosslinked topographies fabricated via in-situ micro-melting and its application as superior Lithium-ion battery separator with shutdown function

摘要: Abstract With more and applications of Lithium-ion batteries (LIBs) in electronics, Polyolefin (PO) separators, including Polyethylene (PE) Polypropylene (PP) cannot meet the increasing requirements high performance LIBs. Separators with good thermal stability electrochemical are great demand. In this paper, Polyetherimide (PEI) fibrous membrane separators crosslinking network morphologies have been successfully fabricated via electrospinning in-situ micro-melting technique. The process converts loose weak PEI nonwoven to compact robust crosslinked membrane, then improves tensile strength from 4 MPa 21 MPa. structure greatly reduces risk disassembling into nonwovens during long-term battery cycling, consequently results Differential Scanning Calorimetry (DSC) Thermogravimetric Analysis (TGA) show that presents excellent (5% weight loss at about 522.2 °C) dimensional (without shrinkage below 240 °C), better than Celgard-2400 separator. LIB separator shows higher capacity (113.3 mAh g−1, 5 C) (95.2 mAh g−1, 5 C). More importantly, exhibits shutdown function 260 °C, which provides a safe guarantee under temperature. All above-mentioned properties make candidate as LIB.