Hung C.-H.,National Chung Hsing University |
Chiu C.-H.,National Chung Hsing University |
Wang S.-P.,National Chung Hsing University |
Chiang I.-L.,CeTech Ltd. |
Yang H.,National Chung Hsing University
International Journal of Hydrogen Energy | Year: 2012
This research studies an ultra-thin carbon fiber paper fabrication process for proton exchange membrane fuel cells (PEMFCs). Polyacrylonitrile (PAN) based carbon fibers 6 mm long were dispersed and formed at aerial weights of 15 and 20 g/m 2 using a slurry molding machine. Polyscrylamide (PAM) and polyvinyl alcohol (PVA) dispersal agent solutions for fiber binding were added to evenly distribute the carbon fibers and increase the paper mechanical strength. The carbon fiber papers were dried after resin impregnation using a convective oven at 120°C temperature for 10 min. The hot press machine was heated to 160°C temperature and the workpieces were pressed for 5 min. Graphitization completed the gas diffusion substrate (GDS) process. GDL involves immersing the paper in a 5% polytetrafluoroethylene (PTFE) solution, coating the paper with a micro porous layer (MPL). This study shows the proposed ultra-thin GDL fabrication method is suitable for PEMFC applications and exhibits feasible functionality for fuel cells. © 2012 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Yang H.,National Chung Hsing University |
Yang H.,CeTech Co. |
Tu H.-C.,CeTech Co. |
Chiang I.-L.,CeTech Co.
International Journal of Hydrogen Energy | Year: 2010
Carbon fiber cloth based on PAN (polyacrylonitrile) material was woven and fabricated into the gas diffusion layer (GDL) for PEMFC applications. This paper describes the newly developed carbon cloth as GDL and proves its feasibility for PEMFC. Such carbon cloth based GDLs have performance equal to that of conventional carbon papers verified using the standard test instrument. The mechanical tests show that as a supporting base, carbon cloth is more practical than carbon paper because of its superior compressibility, elasticity, and flexibility performance, making it more appropriate for ongoing manufacturing and assembly processes. Furthermore, even though carbon paper is structurally flatter and smoother than carbon cloth, the discharge curves of both substrates coated with a MPL (micro-porous layer) showed similar current density (around 750 mA/cm2) at 0.6 V. This indicates that the developed carbon cloth with MPL has achieved the required performance and provides an alternative selection from carbon paper as GDL. © 2009 Professor T. Nejat Veziroglu.