High performance disulfonated poly(arylene ether sulfone)/poly(ethylene oxide) composite membrane used as a novel separator for supercapacitor with neutral electrolyte and activated carbon electrodes.

High performance disulfonated poly(arylene ether sulfone)/poly(ethylene oxide) (SPAES/PEO) composite membranes were prepared by a simple method such as a novel separator saturated by the lithium sulfate (Li₂SO₄) aqueous electrolyte for application in supercapacitors (SCs). As prepared composite membranes exhibit excellent mechanical properties and thermal stabilities, which are beneficial for the safety in potential applications, meanwhile, the addition of PEO on membrane also enhanced the affinity with electrolyte and the ion conduction for lithium salts. In addition, the SC cell was fabricated with optimized SPAES/PEO composite membrane and activated carbon electrodes with Li₂SO₄ aqueous electrolyte. The obtained SC with the SPAES/PEO separator revealed a specific capacitance of 142.5 F g⁻¹ at a current density of 0.1 A g⁻¹. Furthermore, the energy density of the SC was promoted to 19.04 Wh kg⁻¹ due to the wide working voltage range of the neutral electrolyte, and the SC exhibited an excellent coulombic efficiency of almost 99% and nearly 100% cycling retention after 5000 galvanostatic charge/discharge cycles. All of these results indicated that SPAES/PEO composite membrane is suitable as a novel separator for SC. [ABSTRACT FROM AUTHOR]