(557e) Performance and Durability of Vapor-Fed Unitized Regenerative Fuel Cells
AIChE Annual Meeting
2021
2021 Annual Meeting
Transport and Energy Processes
Advanced Electrochemical Energy Storage Technologies III
Wednesday, November 17, 2021 - 1:20pm to 1:45pm
In this study, a URFC using a water vapor feed (vapor-URFC) in electrolysis mode is presented as an alternative option. Using water vapor allows the vapor-URFC to operate exclusively in gas phase, which reduces transition times between the two operating modes. We compare the performance of the vapor-URFC to a traditional URFC operating in the constant gas configuration, in which hydrogen reactions (oxidation and evolution) occur at one electrode, and oxygen reactions (reduction and evolution) occur at the other electrode. Performance and durability of the cell are assessed by measuring polarization curves and performing accelerated stress tests. Preliminary results show that a vapor-URFC is able to obtain current densities of 2 A/cm2 at 0.2 V and at 2 V during fuel cell and electrolysis operation, respectively. A vapor-URFC is also able to achieve a round trip efficiency of 60% at 1 A/cm2. Furthermore, we present a parametric study of different ion exchange membranes and porous transport layers to determine the optimal architecture for the vapor-URFC cell. Finally, we analyze the performance of the vapor-URFC over a range of relative humidities and using varying carrier gases to demonstrate the viability of this device in a variety of operating conditions.