A review: Fluid dynamic and mass transport behaviour in a proton exchange membrane fuel cell stack

Findings on PEMFC designs grew tremendously in the past decade. Commercially, PEMFCs are usually configured in a stack to achieve higher electrochemical output. However, the two-phase fluid transport in a multiple-cell stack raises the complexity of reactant diffusion towards the porous electrodes than a single-cell stack as the higher current generation naturally increases water and heat production. Ensuring optimum hydration with even thermal distribution is critical in maintaining the MEA durability and overall electrochemical performance. Therefore, this review paper provides a comprehensive discussion of how the inconsistencies in water and thermal distribution impact the electrochemical reactiveness within the cell and electrode layers of a multiple-cell PEMFC stack. Targeting the bipolar plate design is not only essential for uniform fluid distribution but it can also be used to maximise the contact surface area to achieve a greater reactant consumption rate. Hence, the effect of varying manifold, flow field and distribution zone designs towardthe fluid and reaction dynamics per cell of a multiple-cell stack were discussed based on available literature. Although the difference in water and heat saturation between single- and multiple-cell stacks could be highlighted clearly in this paper, more research is needed particularly for novel bipolar plate designs. This would be essential knowledge in generating an optimal bipolar plate design that can enhance the durability and performance of PEMFC stacks.