Durability and stability test of proton exchange membrane fuel cells prepared from polybenzimidazole/poly(tetrafluoro ethylene) composite membrane

✍ Scribed by H.L. Lin; Y.S. Hsieh; C.W. Chiu; T.L. Yu; L.C. Chen

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 826 KB
• Volume: 193
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2009.01.062

✦ Synopsis

It has been reported that a thin polybenzimidazole (PBI)/poly(tetrafluoro ethylene) (PTFE) composite membrane (thickness 25-30 m) can be prepared by impregnating a thin porous PTFE (thickness 15-20 m) in a PBI/N,N -dimethyl actamide (DMAc) solution. In this paper, a 400 h life test of a fuel cell prepared from PBI/PTFE composite membrane was carried out at 160 • C with a current density i = 200 mA cm -2 . During long time test, the i-V curve and AC-impedance measurements were conducted every 12 h. The experiment data showed a 240 h period of activation. After 240 h the cell voltage started to decay. AC-impedance measurements showed internal resistance (R s ) and charge transfer resistance (R c ) decreased in the initial 240 h life test and then R s remained almost constant and R c increased after 240 h. The decay of fuel cell performance can be attributed to the migration of phosphoric acid out from membrane leading to the delamination between membrane and electrodes.