Ultrathin reinforced composite separator for alkaline water electrolysis: Comprehensive performance evaluation

Porous PPS membranes are commonly employed to separate the released gases in conventional alkaline electrolyzers. However, their poor ionic conductivity and high gas permeability bring up the issues of high energy consumption and rapidly raised safety risks when the electrolyzers operate at high-pressure levels. Therefore, it is of great significance to develop alternative membranes with superior conductivity and gas tightness. In this study, we prepared an ultrathin composite membrane with support layer via combination of hot-pressing and phase inversion precipitation techniques. The comprehensive performances of the prepared membranes, commercial PPS fabric and commercial Zirfon membrane were compared. The cell performance of the prepared membranes and commercial membranes at high current density was also evaluated. The ultrathin composite membrane exhibits lower cell voltage and ionic resistance than commercial membranes. With the introduction of support layer, the tensile strength of the prepared ultrathin composite membrane significantly increased by 19 times.