A fuel cell has been considered as an efficient and clean alternative power source for automobile industry since the energy crisis forced people to find a substitution for fossil fuels. A proton exchange membrane fuel cell, also known as polymer electrolyte membrane fuel cell (PEMFC), becomes a prime candidate for applications in vehicles because of its following features: the PEMFC operates at...

A portable proton exchange membrane (PEM) fuel cell operates at room temperature, has an energy density which is 4 to 6 times larger than that of a Li-ion battery, and thus is a promising next generation power source for power-hungry portable devices. However, in spite of the high energy density, fuel cells have limited power capacity and cannot respond to sudden changes in the load. Thus, a sy...

Maintaining a fuel cell system in correct operating conditions when subjected to fast load changes requires good system control. In order to design such a controller, a simple PEFC system model describing all the important system dynamics and cross couplings is required. The simple model shown here describes the fuel cell auxiliary systems in a state space approach, linking user input to fuel c...

“Ignition/extinction” phenomena and steady-state multiplicity were discovered in an autohumidi$cation polymer electrolyte membrane fuel cell. At steady state, the water produced by the fuel cell reaction is balanced by water removal by the 7owing reactant gas streams. Ignition, corresponding to a high fuel cell current, arises from positive feedback between the water produced by the reaction an...

A nonlinear fuel cell system dynamic model that is suitable for control study is presented. The transient phenomena captured in the model include the flow characteristics and inertia dynamics of the compressor, the manifold filling dynamics, and consequently, the reactant partial pressures. Characterization of the Fuel Cell polarization curves based on time varying current, partial oxygen and h...

Direct alcohol fuel cells have been attracting enormous research interest as power sources for vehicles and portable electronic devices because alcohols are readily available, their storage and transport can be easily handled with the existing fuel infrastructure, and they commonly have high mass-specific and volumetric energy densities. Methanol is the most studied fuel for direct alcohol fuel...

Microbial fuel cells utilises waste carbohydrates as fuel. It has the property of not utilising a catalyst or proton exchange membrane and it is thus eco-friendly for treating wastes. Biological fuel cell converts chemical energy directly into electrical energy. They are in light because they act in very mild conditions such as ambient temperature, pressure, and inexpensive catalysts i.e. micro...

The Chariton Valley Biomass Power Project, sponsored by the U. S. Department of Energy Biomass Power Program, has the goal of converting switchgrass grown on marginal farmland in southern Iowa into electric power. Two energy conversion options are under evaluation: co-firing switchgrass with coal in an existing utility boiler and gasification of switchgrass for use in a carbonate fuel cell. Thi...