Numerical Study on the Effect of an Improved Three-Partition Baffle Flow Field on Proton Exchange Membrane Fuel Cell Performance

The proton exchange membrane fuel cell (PEMFC) is a type of efficient and environmentally friendly battery. The structure of its bipolar plate directly affects reactant transport and liquid water removal and thereby affects the fuel cell performance. An improved three-partition trapezoidal baffle flow field based on the conventional trapezoidal baffle flow field design is proposed in this paper. A three-dimensional multiphase PEMFC model was established by considering the Forchheimer inertial effect. The mass-transfer characteristics and fuel cell performance of the improved three-partition baffle flow field were compared with those of the conventional parallel flow field and ordinary trapezoidal baffle flow field. It was observed that both improved three-partition baffle flow field and ordinary trapezoidal baffle flow field reduced the flow velocity near the baffle to enhance the inertial effect and mass transfer. In addition, improving the three-partition baffle flow field by further optimizing the baffle heights in different regions of the ordinary trapezoidal baffle flow field improved the transverse flow transmission and the inertial effect near the three-partition baffles. The water removal capability of the porous electrode and the PEMFC performance also improved. The net power of the improved three-partition baffle flow field increased by 4.8% compared with that of the conventional parallel flow field. This study provides an effective reference for the study of the PEMFC bipolar plate structure.