PEM Fuel Cell Fundamentals

A fuel cell is an electrochemical device that continuously and directly converts the chemical energy of externally supplied fuel and oxidant to electrical energy. Fuel cells are customarily classified according to the electrolyte employed. The five most common technologies are polymer electrolyte membrane fuel cells (PEM fuel cells or PEMFCs), alkaline fuel cells (AFCs), phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs) and solid oxide fuel cells (SOFCs). However, the popularity of PEMFCs, a relatively new type of fuel cell, is rapidly outpacing that of the others. 

Unlike most other types of fuel eells, PEMFCs use a quasi-solid eleetrolyte, whieh is based on a polymer baekbone with side-ehains possessing aeid-based groups. The numerous advantages of fliis family of eleetrolytes make the PEM fuel eell partieularly attractive for smaller-scale terrestrial applieations sueh as transportation, home-based distributed power, and portable power applieations. The distinguishing features of PEMFCs inelude relatively low-temperature (under 90 °C) operation, high power density, a eompact system, and ease in handling liquid fuel. 

In 1937, Francis T. Bacon, an Englishman, started to work on practical fuel cells. By the end of the 1950s [1] he had developed a 40-cell stack capable of 5 kW. The stack was able to power a welding machine, circular saw, and foiklilt. 

The PEM fuel cell was invented at General Electric (GE) in the early 1960s, through the work of Thomas Grubb and Leonard Niedrach. Initially, sulfonated polystyrene membranes were used as the solid electrolytes, but these were soon replaced by Nation membranes in 1966. The Nation membrane has proved to be superior in performance and durability, and it is still the most popular membrane in use today. 

Bladder plate Piston Plasic plate Flow fields 

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Yuan, X. Z., Wang, H. (2008). PEM fuel cell fundamentals. PEM Fuel Cell Electrocatalysts and Catalyst Layers Fundamentals and Annlications. Springer London pp. 1-87. 

Yuan X-Z, Song C, Wang H et al (2010) Electrochemical impedance spectroscopy in PEM fuel cells fundamentals and applications, 1st edn. Springer, London... 

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