Synthesis of PVDF/SiO2 nanofiber membrane using electrospinning method as a Li-ion battery separator

Abstract

Abstract This work reported synthesis of PVDF/SiO2 (Polyvinilidene fluoride/Silica) nanofiber membrane by electrospinning method that was used as a separator in li-ion battery. The effect of the SiO2 nanoparticle addition to the PVDF nanofiber membrane to improve membrane characteristics which include porosity, temperature stability, mechanical strength and the stability of battery capacity were systematically investigated. The electrospinning parameter was adjusted at a voltage of 15 kV, the flow rate of 1,5 ml/hour, the distance between needle to collector 17 cm and spinning time for 1 h. The immersion of PVDF membrane in colloid SiO2 nanoparticles was carried out for 1 h. Nanofiber membrane was characterized by SEM (Scanning Electron Microscope), n-butanol intrusion, the dimensional changes before and after heat treatment, stress–strain mechanical measurements with autograph and battery analyzer. The PVDF nanofiber membrane has a beaded fiber with an average fiber size was ∼656 nm. The nanoparticle SiO2 formed double layer on the PVDF membrane. The porosity of PVDF without SiO2 and PVDF/SiO2 3000 ppm is 57% and 70%, respectively. The effect of addition SiO2 to mechanical strength were increased until 2.7 MPa and the membrane were stable at 150 °C for 30 min. The electrochemical performance test by using the produced PVDF membrane has a higher specific capacity than using PP membrane that is 104.6 mAh/g. The addition of SiO2 nanoparticles increased the PVDF membrane capacity stability for 6 cycles by the decline of specific capacity of 42.7 mAh/g for PVDF membrane to 18.7 mAh/g with the addition of 3000 ppm SiO2 nanoparticles.