Title :
Novel Structure for Passive CO2Degassing in μ DMFC
Author :
Litterst, C. ; Eccarius, S. ; Hebling, C. ; Zengerle, R. ; Koltay, P.
Author_Institution :
University of Freiburg – IMTEK, Laboratory for MEMS Applications, Georges-Koehler-Allee 106, D-79110 Freiburg, Germany, e-mail: litterst@imtek.de
Abstract :
A new flowfield design enabling fully passive CO2-gas bubble removal from the anode of a micro direct methanol fuel cell (µ DMFC) is presented. The flowfields channels have an upside down T-shaped cross-section with defined opening angles along their axis and cross-section. The angles create an intrinsic transport mechanism removing growing gas bubbles from the electrode by capillary forces only. Applicable opening angles α and β are 5 ° and 1.5 ° respectively. The experimental verification has been done based on a transparent flowfield and by a fully operational µ DMFC delivering a power density output of up to 8 mW/cm2without the need of external pumps. Although the fuel cell supply can be operated both passively and pump assisted, the passive operation shows the highest efficiency.
Keywords :
Anodes; Batteries; Electrodes; Fuel cells; Laboratories; Methanol; Microchannel; Micromechanical devices; Micropumps; Solar energy;
Conference_Titel :
Micro Electro Mechanical Systems, 2006. MEMS 2006 Istanbul. 19th IEEE International Conference on
Conference_Location :
Istanbul, Turkey
Print_ISBN :
0-7803-9475-5
DOI :
10.1109/MEMSYS.2006.1627746
