Heat and Mass Transport Analysis of Polymer Electrolyte Membrane Fuel Cell With Bipolar Plates

Fuel cells convert chemical energy of fuels into electricity directly. Their higher efficiency and low emissions made them prime candidates for next generation power requirements. The Polymer Electrolyte Membrane (PEM) fuel cell has gained attention of both transportation and stationary power generation industries. In this study a three-dimensional computational model for the simulation of Polymer Electrolyte Membrane (PEM) fuel cell unit cell is developed to understand the complex internal mechanisms, and evaluate the effects of bipolar plate designs on the cell performance. The model includes combined heat and mass transfer processes due to convection and diffusion in the gas flow channels of bi-polar plates as well in the gas diffusion layers of the electrodes, and associated electrochemical reactions in a tri-layer PEM fuel cell. Simulation is carried out with straight parallel channels for operating current density in the range from 0.5–1.5 A/cm² showed significant insight details of PEM fuel cell in terms of distribution of reactant gases, and heat and water transport across the cell. A significantly high variation in gas concentration across the electrode–membrane interfaces and along the channel length is noticed, requiring higher stoichiometric ratios to increase the limiting current density.