Interfacial water distribution behaviors in high performance bipolar membrane fuel cell

The acidic-alkaline interface of a bipolar membrane fuel cell (BPMFC) is the place to generate water, which significantly affect the output performance of BPMFC by regulating the water distribution due to the ion conductivity and oxygen reduction reaction (ORR) kinetics in cathode. To investigate the influence of water diffusivity ( D w ) on the water distribution, four alkaline polymer electrolytes with different D w is selected as anion exchange membrane or alkaline electrolyte ionomer to assemble BPMFCs. A combined experimental and simulated study reveals the positive correlation relationship of D w to the water distribution and performance of BPMFC. By increasing the D w of the alkaline polymer electrolytes, the interfacial-generated water amount can be increased and promptly transport to the cathode, thereby satisfying the ion conductivity and increasing the ORR kinetics, and breakthrough the peak power density of the BPMFC with 1.06 W cm −2 without humidification .