Abstract
For PEMFC operation, water management is very important to provide both sufficient proton conductivity and mass transport. Therefore, in this study, the effect of the relative humidity (38-87%) on cell performance is examined for PEMFC MEAs with various Nafion® ionomer contents. The MEAs were fabricated using a CCM (catalyst-coated membrane) spraying method. As the relative humidity of the cathodes (RHC) increases, the cell voltages at 0.4 and 1.2 A/cm2 increased for a MEA with 20 wt% ionomer. This can be explained in terms of the expansion of active sites with enhanced ionic conductivity (activation overpotential). In contrast, with a higher RHC value, the cell voltages for 35 wt% ionomer (more hydrophilic) gradually decreased as a result of slower gas transport (concentration overpotential). For MEAs with intermediate ionomer contents, 25 and 30 wt%, the cell voltages at 0.4 A/cm 2 showed maximum values at a RHC of 67%, at which point the mass transport begins to be the more dominant factor. The highest unit cell performance was observed in a MEA with an ionomer content of 25 wt% at a RHC of 59% and in a MEA at 20 wt% ionomer content at a higher humidity of 87%.
Original language | English |
---|---|
Pages (from-to) | 13104-13110 |
Number of pages | 7 |
Journal | International Journal of Hydrogen Energy |
Volume | 35 |
Issue number | 23 |
DOIs | |
Publication status | Published - 2010 Dec 1 |
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Keywords
- CCM (catalyst-coated membrane) spraying method
- MEA (membrane-electrode assembly)
- Nafion ionomer
- PEMFC (polymer electrolyte membrane fuel cell)
- Relative humidity
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Condensed Matter Physics
- Energy Engineering and Power Technology
Cite this
The effects of relative humidity on the performances of PEMFC MEAs with various Nafion® ionomer contents. / Kim, Kun Ho; Lee, Kwan Young; Lee, Sang Yeop; Cho, Eunae; Lim, Tae Hoon; Kim, Hyoung Juhn; Yoon, Sung Pil; Kim, Sae Hoon; Lim, Tae Won; Jang, Jong Hyun.
In: International Journal of Hydrogen Energy, Vol. 35, No. 23, 01.12.2010, p. 13104-13110.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The effects of relative humidity on the performances of PEMFC MEAs with various Nafion® ionomer contents
AU - Kim, Kun Ho
AU - Lee, Kwan Young
AU - Lee, Sang Yeop
AU - Cho, Eunae
AU - Lim, Tae Hoon
AU - Kim, Hyoung Juhn
AU - Yoon, Sung Pil
AU - Kim, Sae Hoon
AU - Lim, Tae Won
AU - Jang, Jong Hyun
PY - 2010/12/1
Y1 - 2010/12/1
N2 - For PEMFC operation, water management is very important to provide both sufficient proton conductivity and mass transport. Therefore, in this study, the effect of the relative humidity (38-87%) on cell performance is examined for PEMFC MEAs with various Nafion® ionomer contents. The MEAs were fabricated using a CCM (catalyst-coated membrane) spraying method. As the relative humidity of the cathodes (RHC) increases, the cell voltages at 0.4 and 1.2 A/cm2 increased for a MEA with 20 wt% ionomer. This can be explained in terms of the expansion of active sites with enhanced ionic conductivity (activation overpotential). In contrast, with a higher RHC value, the cell voltages for 35 wt% ionomer (more hydrophilic) gradually decreased as a result of slower gas transport (concentration overpotential). For MEAs with intermediate ionomer contents, 25 and 30 wt%, the cell voltages at 0.4 A/cm 2 showed maximum values at a RHC of 67%, at which point the mass transport begins to be the more dominant factor. The highest unit cell performance was observed in a MEA with an ionomer content of 25 wt% at a RHC of 59% and in a MEA at 20 wt% ionomer content at a higher humidity of 87%.
AB - For PEMFC operation, water management is very important to provide both sufficient proton conductivity and mass transport. Therefore, in this study, the effect of the relative humidity (38-87%) on cell performance is examined for PEMFC MEAs with various Nafion® ionomer contents. The MEAs were fabricated using a CCM (catalyst-coated membrane) spraying method. As the relative humidity of the cathodes (RHC) increases, the cell voltages at 0.4 and 1.2 A/cm2 increased for a MEA with 20 wt% ionomer. This can be explained in terms of the expansion of active sites with enhanced ionic conductivity (activation overpotential). In contrast, with a higher RHC value, the cell voltages for 35 wt% ionomer (more hydrophilic) gradually decreased as a result of slower gas transport (concentration overpotential). For MEAs with intermediate ionomer contents, 25 and 30 wt%, the cell voltages at 0.4 A/cm 2 showed maximum values at a RHC of 67%, at which point the mass transport begins to be the more dominant factor. The highest unit cell performance was observed in a MEA with an ionomer content of 25 wt% at a RHC of 59% and in a MEA at 20 wt% ionomer content at a higher humidity of 87%.
KW - CCM (catalyst-coated membrane) spraying method
KW - MEA (membrane-electrode assembly)
KW - Nafion ionomer
KW - PEMFC (polymer electrolyte membrane fuel cell)
KW - Relative humidity
UR - http://www.scopus.com/inward/record.url?scp=78049453756&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78049453756&partnerID=8YFLogxK
U2 - 10.1016/j.ijhydene.2010.04.082
DO - 10.1016/j.ijhydene.2010.04.082
M3 - Article
AN - SCOPUS:78049453756
VL - 35
SP - 13104
EP - 13110
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
SN - 0360-3199
IS - 23
ER -