Numerical analysis on polymer electrolyte membrane fuel cell performance enhancement with novel selective-patterned gas diffusion layers

To improve the performance of polymer membrane electrolyte fuel cells (PEMFCs), many studies dealing with flow fields, including those related to the channel and gas diffusion layer (GDL), have been conducted. Especially, the GDL, which is an important component that determines the PEMFC performance, has been used as a diffusion media which covers all reaction sites between the channel and catalyst layer. The common rectangular shape of the GDL enables the diffusion of the reactant under the rib. However, it results in the deterioration of mass transport under the channel. In this study, GDLs that have a shape like a rib are devised, which enable the diffusion under the rib and better mass transport under the channel. Then, the selective-patterned GDL are applied to PEMFCs having different cathode channel types of serpentine, parallel, and interdigitated channels. The PEMFCs having serpentine and parallel channels with selective-patterned GDLs show better performance under all voltage conditions. The performance of serpentine and parallel channel PEMFC was improved 6.0% and 6.7% respectively at 0.5V voltage condition. The interdigitated channel PEMFC having a selective-patterned GDL does not show the remarkable improvement obtained for other channel types using a selective-patterned GDL and the improvement was only 1.6% at 0.5V voltage condition. However, for the volume power density, all analysis results of cases having a selective-patterned GDL are better than the cases with a normal GDL and the improvement degreed of volume power density of serpentine, parallel and interdigitated channel PEMFC was 14.0, 14.7 and 9.2% respectively at 0.5V voltage condition.