Development of 100w portable fuel cell system working with sodium borohydride

Download
2011
Erkan, Serdar
Fuel cells are electricity generators which convert chemical energy of hydrogen directly to electricity by means of electrochemical oxidation and reduction reactions. A single proton exchange membrane (PEM) fuel cell can only generate electricity with a potential between 0.5V and 1V. The useful potential can be achieved by stacking cells in series to form a PEM fuel cell stack. There is a potential to utilize 100W class fuel cells. Fuelling is the major problem of the portable fuel cells. The aim of this thesis is to design and manufacture a PEM fuel cell stack which can be used for portable applications. The PEM fuel cell stack is planned to be incorporated to a NaBH4 hydrolysis reactor for H2 supply. Within the scope of this thesis a new coating technique called “ultrasonic spray coating technique” is developed for membrane electrode assembly (MEA) manufacturing. New metal and graphite bipolar plates are designed and manufactured by CNC technique. A fuel cell controller hardware is developed for fuel supply and system control. The power densities reached with the new method are 0.53, 0.74, 0.77, and 0.88 W/cm2 for 20%, 40%, 50%, 70% Pt/C catalyst by keeping 0.4mg Pt/cm2 platinum loading constant, respectively. The power density increase is 267% compared to “spraying of catalyst ink with air pressure atomizing spray gun”. All parts of the PEM fuel cell stack designed were produced, assembled, and tested. The current density reached is 12.9A at 12 V stack potential and the corresponding electrical power of the stack is 155W.

Suggestions

Parameters influencing long term performance and durability of PEM fuel cells
Şayin, Elif Seda; Eroğlu, İnci; Bayrakçeken, Ayşe; Department of Chemical Engineering (2011)
Fuel cells are the tools which convert chemical energy into electricity directly by the effective utilization of hydrogen and oxygen (or air). One of the most important barriers for the fuel cell commercialization is the durability of the fuel cell components in the long term operations. In this study, the durability of the PEM fuel cell electrocatalysts were investigated via cyclic voltammetry (CV) and rotating disk electrode (RDE) experiments in order to determine the hydrogen oxidation reaction (HOR) and...
Development of anodes for direct oxidation of methane fuel in solid oxide fuel cells
Akdeniz, Yelda; Timurkutluk, Bora; Timurkutluk, Cigdem (2016-06-22)
In addition to pure hydrogen, solid oxide fuel cells (SOFCs) can utilize hydrocarbons as a fuel. However, conventional Ni-based anodes exhibit an excellent catalytic activity towards the hydrocarbon cracking reaction and thus the carbon deposition occurs in the anode. The deposited carbons quickly deactivate the anode irreversibly by covering the active surface of the anode catalyst. As a result, a significant degradation in the cell performance can be seen. In this study, the anode structure is modified by...
Development of 500 W PEM fuel cell stack for portable power generators
DEVRİM, YILSER; Devrim, Huseyin; Eroğlu, İnci (2015-06-29)
Polymer Electrolyte Membrane Fuel Cell (PEMFC) portable power generators are gaining importance in emergency applications. In this study, an air-cooled PEMFC stack was designed and fabricated for net 500 W power output. Gas Diffusion Electrodes (GDE's) were manufactured by ultrasonic spray coating technique. Stack design was based on electrochemical data obtained at 0.60 V was 0.5 A/cm(2) from performance tests of a single cell having the same membrane electrode assemblies (MEA) that had an active area of 1...
MODELING OF BIPOLAR PLATES FOR PROTON EXCHANGE MEMBRANE FUEL CELLS
Ekiz, Ahmet; Camci, Talha; Turkmen, Ibrahim; SANKIR, MEHMET; USLU, SITKI; Baker, Derek Keıth; Agar, Ertan (2011-09-01)
Fuel cell technology is one of the most economic and efficient ways to utilize hydrogen energy. Various types of fuel cells are present regarding the fuel type and amount of power produced. Among these, proton exchange membrane fuel cells (PEMFCs) are very promising. In this work, a 2D proton exchange membrane fuel cell unit cell was modeled using Comsol Multiphysics software. Cell section was taken parallel to flow direction. Obstacles with various geometries were placed in the flow channel in order to for...
Numerical investigation of a stand alone solar hydrogen energy system effects of PEFC degradation
Ender, Ozden; Tarı, İlker (null; 2015-08-12)
An existing stand-alone solar energy system producing hydrogen for energy storage is numerically investigated focusing on the degradation of Polymer Electrolyte Fuel Cell (PEFC) and its effects on the overall performance of the system. The system consists of Photovoltaic (PV) panels, polymer electrolyte based electrolyzers, H2 and O2 storage tanks and a commercial PEFC stack. A PEFC is numerically investigated both as new and as degraded (for about two years). Using a variety of observed degradation pattern...
Citation Formats
S. Erkan, “Development of 100w portable fuel cell system working with sodium borohydride,” Ph.D. - Doctoral Program, Middle East Technical University, 2011.