Open AccessImproved Flow-Field Structures for Direct Methanol Fuel Cells
Author(s) -
Bogdan Gurauꝉ
Publication year - 2013
Language(s) - English
Resource type - Reports
DOI - 10.2172/1114198
Subject(s) - anode , cathode , methanol fuel , direct methanol fuel cell , methanol , power density , hydrogen fuel , chemical engineering , hydrogen , diffusion layer , diffusion , materials science , process engineering , chemistry , nuclear engineering , layer (electronics) , nanotechnology , power (physics) , thermodynamics , engineering , organic chemistry , electrode , physics
The direct methanol fuel cell (DMFC) is ideal if high energy-density liquid fuels are required. Liquid fuels have advantages over compressed hydrogen including higher energy density and ease of handling. Although state-of-the-art DMFCs exhibit manageable degradation rates, excessive fuel crossover diminishes system energy and power density. Although use of dilute methanol mitigates crossover, the concomitant lowering of the gross fuel energy density (GFED) demands a complex balance-of-plant (BOP) that includes higher flow rates, external exhaust recirculation, etc. An alternative approach is redesign of the fuel delivery system to accommodate concentrated methanol. NuVant Systems Inc. (NuVant) will maximize the GFED by design and assembly of a DMFC that uses near neat methanol. The approach is to tune the diffusion of highly concentrated methanol (to the anode catalytic layer) to the back-diffusion of water formed at the cathode (i.e. in situ generation of dilute methanol at the anode layer). Crossover will be minimized without compromising the GFED by innovative integration of the anode flow-field and the diffusion layer. The integrated flow-field-diffusion-layers (IFDLs) will widen the current and potential DMFC operating ranges and enable the use of cathodes optimized for hydrogen-air fuel cells