Performance Analysis of PEMFC with Non-Equidistant Depth 3D Flow Field

A well-designed flow field structure can effectively reduce mass transport losses in Proton Exchange Membrane Fuel Cell (PEMFC) under high current densities. Most optimization designs focus on two-dimensional equidistant-depth flow fields, while research on nonequidistant-depth three-dimensional flow fields remains limited. This study introduces a novel nonequidistant-depth 3D flow field and utilizes rapid laser ablation technology to fabricate metal bipolar plates. Numerical simulations are performed to analyze gas flow velocity, reactant distribution, and fuel cell performance across flow field structures with varying inclinations and trapezoidal block heights. Results indicate that optimal fuel cell performance is achieved with a flow field where the channel tilt height and trapezoidal block height are both 0.3 mm. Compared to the parallel flow field, the proposed design significantly enhances flow velocity at the Channel-GDL interface and ensures a higher, more uniform reactant concentration at the GDL-CL interface. The maximum power density reaches 1.551 W/cm², representing a 39.48% increase, with only a 10.79% rise in water content, highlighting effective water management.