Experimental evaluation of flow field design on open-cathode proton exchange membrane fuel cells (PEMFC) short stack consisting of three cells

The promising nature of proton exchange membrane fuel cell stacks in energy conversion has sparked the need to improve the cell components for improved performance, durability, sustainability, and cost competitiveness. This work presents the pros and cons of different flow field designs concluded from an open-cathode short stack, composed of three cells. The flow fields consist of 3D fine mesh, fine wire mesh, metal foam, and conventional straight channels. The results presented in this study show that the fine wire mesh gives better performance, both when integrated, and not integrated with straight channels. It is followed by the 3D fine mesh, straight channels, and metal foam. The different performance improvements are caused by the various flow fields influencing flow rate, current conductivity, and temperature increment. Water management seems to be a significant factor in the performance variation. This is presented by the IV curves, which show a dramatic discrepancy over the concentration loss region. The straight channels integrated with fine wire mesh cell have the highest degradation rate at a constant voltage of 1.7 V, even though it reached a constant value after 1.4 h of operation.