Status of fuel cell technologies and their applications
Fuel cells are devices that convert chemical energy of fuel by electrochemical reactions directly to electricity. Although the operating principle of fuel cells was discovered in XIX century, their intensive development takes place during the last 20 years. Based on the type of electrolyte there are several types of fuel cells, but the most developed are so called Proton Exchange Membrane or Polymer Electrolyte Membrane (PEM) fuel cells. In this presentatin development of PEM fuel cells and their components (membranes, catalysts, bipolar plates, flow fields) and their applications is presented. Besides development of materials for above listed components, research and development activities include investigations of performance degradation with time, modeling of processes inside a fuel cell (electrochemical reactions, heat and mass transport, proton conduction, fluid flow, etc.) and development of advanced diagnostic methods for better understanding of the key processes inside a fuel cell as well as for operation control purposes. Fuel cells have a wide variety of applications – from those small power levels, order of magnitude 1 W, as battery replacement, to portable and stationary power generation and cogeneration, to propulsion of various vehicles (bicycles, scooters, cars, buses, trains and even airplanes). Use in cars gets most of attention, because the fuel cell powered vehicles are beginning to be manufactured in small series and sold commercially.