Dynamic Water Management Studies by means of Perforated GDLs and - - PowerPoint PPT Presentation
Dynamic Water Management Studies by means of Perforated GDLs and In-situ ESEM Observations Robert Alink, Dietmar Gerteisen, Christian Sadeler, Christopher Hebling Fraunhofer Institute for Solar Energy Systems ISE Freiburg, Germany Diagnostic
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Test scope: Examination of the water transport
In-situ single cell experiments and stack experiments Ex-situ visualizing of water transport in untreated and
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Mikroelectronics Production Technology Information and Communication Technology Materials, Devices Life Sciences Surface Technology and Photonics Defense and Security Research
Itzehoe Berlin Golm Magdeburg Hannover Braunschweig Bremen Oberhausen Dortmund Duisburg Aachen Euskirchen Schmallenberg
Ilmenau Jena Dresden Chemnitz Würzburg Erlangen Pfinztal Darmstadt Kaiserslautern
Saarbrücken Karlsruhe Stuttgart Freiburg Freising Rostock Teltow Cottbus Halle Schkopau Paderborn Nürnberg Efringen-Kirchen München Holzkirchen Leipzig Itzehoe Berlin Golm Magdeburg Hannover Braunschweig Bremen Oberhausen Dortmund Duisburg Aachen Euskirchen Schmallenberg
Ilmenau Jena Dresden Chemnitz Würzburg Erlangen Pfinztal Darmstadt Kaiserslautern
Saarbrücken Karlsruhe Stuttgart Freiburg Freising Rostock Teltow Cottbus Halle Schkopau Paderborn Nürnberg Efringen-Kirchen München Holzkirchen Leipzig
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Components Products, Prototypes Systems, Processes
Consulting, Tests Monitoring Quality Assurance
Materials Modelling Methods
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Development of fuel cell systems, stacks and autonomously controlled systems Characterizing and modelling single cells, stacks and systems Control and safety technology
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Water is generated in the
Water flows through
Small filled cavities
Void space gets filled by
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Pressure needed for
Water transport channels
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Investigation of single
Cathode GDL „under the
Holes have a diameter of
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* without anode polarization
different operating
sweep rate 10 mV/s
Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
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Potential sweep
Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
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Potential sweep
Hysteresis knee due to
Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
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Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
Potential sweep
Hysteresis knee due to
Perforated GDL shows
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Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
Chronoamperometriy
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Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
Chronoamperometriy
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Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
Chronoamperometriy
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Enhancing liquid water transport by laser perforation of a GDL in a PEM fuel cell Journal of Power Sources, Vol 177, Issue 2, 1 March 2008, P 348-354
Chronoamperometriy
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Air cooled stack 6 cells Active area of 6 x 31 cm2
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Stability test at 0.71
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Stability test at 0.71
Voltages of outer cells
Higher overall
3 times less purging steps
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Higher Voltage at
Less variation of single
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Higher Voltage after
Lower temperature due
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ESEM working in water
All 3 phases of water
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Freeze / thaw cycling of
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Freeze / thaw cycling of
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Freeze / thaw cycling of
Freeze / thaw cycling of
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Freeze / thaw cycling of
Freeze / thaw cycling of
Wet / dry cycling of MEAs
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ESEM working in water
All 3 phases of water
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Water is „sucked“
Visulization of water
80 800 P 0 Pa 1 °C 1 °C
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Single cell experiments
Significant increase in cell
New method found to