Fuel Cell Cathode Air Filters: Methodologies for Design and Optimization
Type of DegreeThesis
MetadataShow full item record
Platinum catalyst used in PEM fuel cells experience performance degradation such as reduction in efficiency and life as a result of airborne contaminants. Research on these contaminant effects suggests that the best possible solution to allowing fuel cells to operate in contaminated environments is by filtration of the harmful contaminants from the cathode air. A cathode air filter design methodology was created that considers the properties of the cathode air stream, fuel cell attributes, and filter options to optimize the filter design process. Optimization of the filter requires an understanding of the balance that must be made between the loss in power due to poisoning of the platinum catalyst and a loss in fuel cell efficiency created by an increase in parasitic power required to operate the compressor. The model was successfully applied to a 1.2kWe fuel cell. Results show that the optimal filter design is dependent on both the total logs of removal required and the total capacity required. A novel filter media, microfibrous materials, provides the thinnest possible bed depth and lowest parasitic power requirements for cases requiring high logs removal and low capacity. Packed beds provide the best solution for high inlet concentrations and/or long breakthrough time applications. If both a high contacting efficiency and capacity are required, an optimized composite bed provides the ideal solution by utilizing the advantages of both filter types.