A Comparative Study of the Performance of Ultra-Porous Membranes as Separators in Supercapacitor Devices

Commercial porous membranes as well as in-house fabricated ultraporous nonwoven membranes were tested as separators in aqueous carbon-based supercapacitors. The separators were obtained by electrospinning and melt-blowing of nonwoven nano and microfibers. A pressure-controlled laboratory cell was designed and fabricated in order to precisely compare the supercapacitor performance and discriminate the separator influence. The electrochemical results showed that the separator does not influence the capacitance of the cell but has a significant impact on its internal resistance. It was demonstrated that increasing the porosity of the separator led to a decreased cell resistance and then to a higher energy available at high poer demand.