Scalable porous mixed-matrix membranes for energy storage and conversion

The development of alkaline-stable membranes is of paramount importance for the reliable operation of energy-related devices such as flow batteries and water electrolyzers. Intrinsically stable porous membranes are well suited for these devices, yet their integration into commercial-scale cell stacks has been seldom documented. Here, we report the pilot-scale fabrication of porous poly(ether sulfone) (PES)/ZrO 2 mixed-matrix membranes, demonstrating efficient and stable performance in both an alkaline zinc-iron flow battery stack and a lab-scale zero-gap alkaline water electrolyzer stack. The obtained membrane shows only 0.218% mass degradation over 500 h in a 30 wt % KOH solution at 80°C and works efficiently for use in alkaline zinc-iron flow battery single cells, 500 W-scale cell stacks, and alkaline water electrolyzer stacks. This work propels energy-related devices from laboratory-scale development to industrial-scale stack operation, inspiring effective solutions for large-scale energy storage and conversion.