PEM Fuel Cell Systems

Abstract

Proton Exchange Membrane (PEM) fuel cells are extensively used for mobile and portable applications. This is due to their compactness, low weight, high power density, and clean, pollutant-free operation. Besides, their low temperature of operation (typically 60–80 degrees Celsius) allows fast starting times, a key feature for automotive applications, for instance. In a PEM Fuel Cell, a hydrogen-rich fuel is injected by the anode, and an oxidant (usually pure oxygen or air) is fed through the cathode. Both electrodes are separated by a solid electrolyte that allows ionic conduction and avoids electrons circulation. The output of a PEM Fuel Cell is electric energy, with water and heat as the only by-products. In this chapter, the basics of PEM fuel cells operation are reviewed, including electrochemical equations, losses, and efficiency issues. The state-of-the-art in PEM fuel cells technology is summarised, including membranes, electrodes, catalysts, line heaters, water, and heat management devices. Control-oriented models in the literature are discussed, and typical control objectives are analysed.