Performance Evaluation of Metallic Foam Flow Fields

Water management is one of the major areas of interest in the fuel cell research community. Previous studies have shown enhancement in water management and fuel cell performance using a parallel flow field design including a metallic foam structure in the channels of the cathode flow field [1]. In this paper, metallic foams are used in a new geometry and are applied to both cathode and anode flow fields to improve water removal, reduce production costs, and enhance the overall performance. The metallic foam increases turbulent mixing in the flow fields which prevents the formation of a laminar boundary layer at the surface of the gas diffusion layer (GDL). The foam also serves as a moisture wick removing liquid water away from the GDL while maintaining the level of moisture required avoiding dehydration of the membrane. In this study, the performance tests are conducted at a variety of dew point temperatures to determine the water management properties of the metallic foam in the new geometry. The performance of the metallic foam will be compared to that of a standard serpentine graphite flow field. The major criteria will include performance at nominal voltage and current and high current stability.