Proton Exchange Membrane Fuel Cells (PEMFCs) have emerged as one of the most promising clean energy conversion technologies due to their high efficiency, low operating temperature, fast start-up characteristics, and environmentally friendly operation. However, the performance and durability of PEM fuel cells are significantly affected by electrochemical losses, thermal imbalance, membrane dehydration, and inefficient water management. Accurate mathematical modeling and simulation are therefore essential for understanding the coupled electrochemical and thermal phenomena occurring inside the fuel cell system. This study presents an integrated electrochemical and thermal modeling framework for analyzing and enhancing the performance of PEM fuel cells under varying operating conditions. The developed model incorporates activation, ohmic, and concentration overpotentials together with heat generation and heat transfer mechanisms. MATLAB/Simulink-based simulations were employed to investigate the influence of temperature, current density, pressure, and membrane hydration on fuel cell efficiency and voltage characteristics. The results demonstrate that proper thermal regulation and optimized operating parameters significantly improve power density, voltage stability, and system efficiency. The integrated model provides valuable insights for the design, optimization, and control of high-performance PEM fuel cell systems for sustainable energy applications
PEM Fuel Cell, Electrochemical Modeling, Thermal Modeling, Performance Optimization, MATLAB Simulation, Heat Transfer, Energy Efficiency, Hydrogen Energy.