Thermo-osmosis and hydraulic permeability measurements and modeling of different membrane and gas diffusion layers in polymer electrolyte membrane fuel cells

Fuel cells are electrochemical devices that convert directly chemical energy released from electrochemical circuit reactions directly into electrical energy. Polymer Electrolyte Membrane Fuel Cells (PEMFCs) are preferred in many fields due to their high energy efficiency, long service life, near-zero emissions, high power density, and low-temperature operation. Water management on PEMFCs is one of the issues that need to be addressed for better cell performance. In this master's thesis study, an experimental system was designed for thermal diffusion-induced water transport measurements through the membrane electrode assembly (MEA), and MEA materials were prepared and used. The thermal diffusion coefficients were calculated and reported from the measurements, and the importance of the magnitude and sign of the coefficient was noted. In addition, using the nonequilibrium thermodynamics approach, thermal diffusion-induced water transport modeling was carried out throughout the MEA, and it was discussed to why effects such as Heat of Transfer and Soret Coefficient, which are often neglected in PEMFC studies, should not be neglected and how these phenomena can significantly improve fuel cell studies