PVDF/TBAPF6 hierarchical nanofiber gel membrane for lithium ion capacitor with ultrahigh ion conductivity and excellent interfacial compatibility.

An efficient, convenient and flexible polyvinylidene fluoride/tetrabutylammonium hexafluorophosphate hierarchical nanofiber membrane (PVDF/TBAPF6 HNM) was successfully fabricated by one-step electrospinning and used as the separator of Li-ion capacitor (LIC). The PVDF/TBAPF6 HNMs displayed high ion conductivity of 4.28 × 10−3 S/cm, high mechanical strength, porosity, wettability and excellent thermal performance. Furthermore, the separator of PVDF/TBAPF6 HNM possessed lower interfacial resistance (134Ω) and better electrochemical stability, which exhibits better capacity retention and coulombic efficiency, compared with the commercial celgard 2340 separator. We believe that the gel polymer PVDF/TBAPF6 HNMs separator will have great potential in the field of the separator of LIC. The PVDF/TBAPF6 nanofiber gel membrane with hierarchical structure exhibited excellent cycle performance due to the effect of TBAPF6 and hierarchical structure. Image 100 • A hierarchical nanofiber membrane (HNM) was fabricated by electrospinning. • The HNM possessed good mechanical property and excellent thermal stability. • The HNMs showed superior ion conductivity (4.28*10−3 S/cm). • The HNMs exhibited long cycle stability and excellent interfacial compatibility. [ABSTRACT FROM AUTHOR]