Application of template method in fabricating ordered gas diffusion layer of PEMFC

As a core component of proton exchange membrane fuel cell (PEMFC), gas diffusion layer (GDL) takes an important role in the migration of gas, liquid, heat, and electrons. Optimizing GDL microstructure is crucial to improve the gas-liquid flowing behavior and enhance PEMFC performance. Therefore, an ordered GDL is designed by coupling the template method and stacking multiple fiber layers method to provide the large holes for water elimination and the small pores for gas delivery. The ordered GDL possesses excellent mass transfer capacity, which can improve the PEMFC performance compared with commercial GDL under high relative humidity (RH). At RH 100% and 70 degrees C, the PEMFC with ordered GDL achieves the maximum peak power density of 0.92 W cm-2, which realizes an increment of 10.8% compared with commercial GDL. However, with a decrease in RH, the ohmic loss gradually occupies the primary contribution to the performance compared with the mass transfer capacity, resulting in a downward trend of the performance of PEMFC with ordered GDL. This work provides a simple and efficient strategy to design the ordered pore structure of GDL, and the outcomes have the potential of being implemented in the future PEMFC vehicles.