Electrospun PAN membranes strengthened in situ–grown TiO2 particles for high-performance lithium-ion batteries

An in situ–grown TiO 2 membrane was prepared by an electrospinning method using polyacrylonitrile as the spinning precursor, combined with the TiO 2 hydrolysis mechanism. The performance of tetrabutyl titanate and isopropyl titanate as two titanium source precursors hydrolyzed under the inhibition of acrylic acid to produce TiO 2 with different contents for lithium-ion batteries was compared. The experimental results showed that when both titanium sources were prepared at 3 wt%, the comprehensive performance of the separator manufactured with tetrabutyl titanate as the titanium source (PAN/TBT-3) and isopropyl titanate as the titanium source (PAN/TPT-3) was finest than that of the Celgard 2400 and the composite membrane with direct TiO 2 addition (PAN/TiO 2 -3). The tensile strength of PAN/TPT-3 and PAN/TBT-3 membranes were 7.82 MPa and 4.03 MPa higher than that of Celgard 2400, and 17.03 MPa and 13.29 MPa higher than that of PAN/TiO 2 -3 separator, respectively. PAN/TPT-3 and PAN/TBT-3 membranes exhibited a discharge capacity of 107.72 mAh/g and 115.79 mAh/g at 2 C, and both the capacity retention rate was above 99.5% higher than 80.5% for Celgard 2400.