PEMFC 기체확산층 적용을 위한 MWCNT/PTFE 복합재 필름 개발

초록

The unit cell of a polymer electrolyte membrane fuel cell (PEMFC) comprises a separator, a gas diffusion layer, a catalyst layer, and a polymer electrolyte membrane. Among them, a gas diffusion layer (GDL) serves as a passage through which hydrogen and oxygen, which are fuels, are transferred to the catalyst layer, and water is discharged from the fuel cell. GDL is composed of the gas diffusion backing (GDB) made based on carbon fiber paper with high porosity and the micro-porous layer (MPL) that reduces contact resistance with the catalyst layer and facilitates water discharge. In this study, research on MWCNT/PTFE composite film was conducted to apply it as a high-performance GDL for PEMFC. The electrical conductivity, microstructure, contact angle, and activation energy of the composites were analyzed according to the MWCNT content, and water evaporation was observed according to the operating voltage. Finally, the possibility of use as a GDL was confirmed by measuring the change in resistance and thickness, and gas permeability according to the applied pressure in the thickness direction of the MWCNT/PTFE composite film. The results of this research are expected to become the basis for future high-performance PEMFCs and the basis for realizing an eco-friendly hydrogen society.