(697d) Pore Filling Anion Exchange Membranes and Membrane Electrode Assemblies for Solid-State Alkaline Fuel Cells
In solid-state alkaline fuel cells (SAFCs), stability improvement of the membranes and water management of the MEAs are essential to achieve good performances. To improve the stability, suppressing water mobility by porous substrate matrix leads to improve the membrane durability. The pore-filling membranes exhibited higher stability compared with normal cast films made of the same polymer. Next, water management is important for SAFCs because water reacts at the cathode and is generated at the anode, in contrast to proton-exchange membrane fuel cells (PEMFCs). Thus, optimization is required to establish design methodology for SAFCs with pore-filling anion exchange membranes. Water movement in a SAFC system has been observed accurately using a water collection method. We confirm for the first time the movement of water from the anode to the cathode during an actual fuel cell performance test. Compared with a PEMFC, water movement occurs in the opposite direction leading to difficult water management in the SAFC. With the knowledge obtained, controlling membrane performances and careful control of humidity have achieved water management in the SAFCs.