Fuel cells are electrochemical energy converters which allow transformation of the chemical energy of a fuel to electricity through oxido-reduction reaction. The voltage of an elementary cell is usually near 1 V in open circuit and around 0.6 V in nominal conditions of power generation. Fuel cells are then by essence low voltage sources , so that for most practical applications, power managemen...

In present work, numerical analysis of three novel PEM fuel cells with tubular geometry was conducted. Tree different cross section was considered for PEM, namely: circular, square and triangular. Similar boundary and operational conditions is applied for all the geometries. At first, the obtained polarization curve for basic architecture fuel cells was validated with experimental data and then...

A novel sulfonated diamine was synthesized from 1,4-bis(4-aminophenoxy) benzene [pBAB]. Sulfonated polyimides (SPIs) were synthesized from sulfonated pBAB, 1,4-bis(4-aminophenoxy-2-sulfonic acid) benzenesulfonic acid [pBABTS], various diamines and aromatic dianhydrides. Composite proton exchange membranes (PEMs) made of novel SPIs and a protic ionic liquid (PIL) 1-vinyl-3-H-imidazolium trifluor...

This paper reviewed over 100 articles on the subject of the mechanism of catalyst layer (CL) degradation and the effect of various contaminations in the polymer electrolyte membrane fuel cell (PEMFC). Also the recovery of PEMFC via different types of methods, the causes and fundamental mechanisms of cell degradation and their influence on long- term performance of PEM fuel cell were discussed i...

electrochemical impedance spectroscopy (eis) is a suitable and powerful diagnostic testing method for fuel cells (fcs) since it is non-destructive and provides useful information about fc performance and its components. in this study, for the first time, a 500w cascade type 4 cells stack with integrated humidifier, water separator and internal manifolds was designed, fabricated and tested. the ...

Start-up and dynamic responses to changes in load are reported for a dry feed, autohumidified polymer electrolyte membrane fuel cell PEMFC . The fuel cell current can be ignited by water injection; criteria are derived for the required water injection as functions of fuel cell size, temperature, and reactant feed rates. Steady-state multiplicity is observed where the fuel cell current can be ei...

This paper focuses on the energy management control strategy for a hybrid fuel cell powered vehicle. A method based on optimal control theory is presented. This control strategy has been applied to a representative hybrid PEM (Proton Exchange Membrane) fuel cell mid-size vehicle. Simulation results on a priori known driving cycle are presented and compared to a sub-optimal strategy. Copyright ©...

In this paper, we demonstrate a monolithic integrated micro direct methanol fuel cell (μDMFC) for the first time. The monolithic integrated μDMFC combines proton exchange membrane (PEM) and Pt nanocatalysts, in which PEM is achieved by the functionalized porous silicon membrane and 3D Pt nanoflowers being synthesized in situ on it as catalysts. Sulfo groups functionalized porous silicon membran...