Premium
Self Humidifying Hybrid Anion–Cation Membrane Fuel Cell Operated Under Dry Conditions
Author(s) -
Ünlü M.,
Zhou J.,
Kohl P. A.
Publication year - 2010
Publication title -
fuel cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.485
H-Index - 69
eISSN - 1615-6854
pISSN - 1615-6846
DOI - 10.1002/fuce.200900122
Subject(s) - proton exchange membrane fuel cell , ionomer , membrane , cathode , chemical engineering , electrode , electrical conductor , materials science , dielectric spectroscopy , conductivity , membrane electrode assembly , chemistry , analytical chemistry (journal) , anode , composite material , electrochemistry , chromatography , biochemistry , engineering , copolymer , polymer
Hybrid fuel cells composed of a low‐pH proton conductive membrane in contact with a high‐pH anion conductive membrane were investigated. The effect of relative humidity (RH), ionomer content in the anion‐conductive electrode and the inlet gas flow rates were evaluated. The formation of water at the junction of the anion conductive member and proton conductive membrane is especially interesting because it can self‐humidify the fuel cell when dry gases are used. In situ alternative current (AC) impedance spectroscopy was used as a diagnostic tool to understand the performance limitations under different test conditions. The cell output increased at low RH compared to a traditional proton exchange membrane fuel cell. The cell current under dry conditions was limited by the availability of oxygen in the catalyst sites due to flooding in the electrode layer. The ionomer fraction of the high‐pH cathode plays a significant role in the cell performance. At high gas feed rates, water removal from the electrode layers increased and mitigated the effects of flooding. The hybrid cells were operated at steady‐state operation at 0.58 V and 200 mA cm –2 using dry H 2 /O 2 feeds at 80 °C.