Short History

The beginning of the 19th century represents the starting point of research in the field of fuel cells. In 1801 Humphry Davy demonstrated the principle that underlies the functioning of the fuel cell, and later in 1839 the lawyer and amateur scientist William Grove accidentally discovered the principle of the fuel cell during an electrolysis expereriment, when he disconnected the battery from the electrolysis device and touched the two electrodes [49]. He called this cell "gas battery", which consisted of platinum electrodes placed in tubes containing hydrogen gas and oxygen, respectively, tubes submerged in dilute sulfuric acid. The generated voltage was around 1 V. Sometime later, Grove connected several such "gas batteries" in series and used this thus obtained voltage source to supply the electrolyzer that separates the hydrogen from the oxygen. Due to electrode corrosion problems and the instability of the materials used, Grove's fuel cell did not produce practical results [50]. Langer and Mond developed Grove's invention by observing that over time the reactivity phenomenon of platinum black in contact with electrolytes is diminished, and the life of the fuel cell is prolonged by keeping the electrolyte in a non-conducting porous material [42,51], and using in 1889 for the first time the term fuel cell.

Subsequently, the studies were deepened with significant progress, and the 1960s–1970s brought the first practical applications of fuel cells, these being used by NASA for spacecraft. At the same time, the General Electric company was developing fuel cells with proton exchanger membranes, which were the basis of the fuel cells used for the generation of electricity in the Gemini program missions and the Apollo space program [51,52]. Starting in 1990, the research aimed to implement fuel cell technology in stationary applications, and fuel cells of different capacities for use in this field have been developed. Progress on membrane durability and improved energy performance of fuel cell assemblies has prompted the use of phosphoric acid fuel cells (PAFCs) in cogeneration applications and their widespread use [19,31,51].

Also, proton exchange membrane fuel cell (PEMFC) and solid oxide fuel cell (SOFC) technology has been developed for this field, especially for small stationary applications. The year 2000 also marks significant contributions in the field of portable devices, when fuel cell technology with direct methanol (DMFC) is widely adopted and used in this type of applications [19,31,51].

In the last two decades there has been a rapid acceleration in the increase of the use of fuel cells covering a wide diversity of applications in the portable, mobile and stationary fields. These increases are due, on the one hand, to technical progress in the field of fuel cells, and on the other hand, they are driven by global concerns about energy security, efficiency, energy sustainability, reducing greenhouse gas emissions and not least, decreasing dependence on the use of fossil fuels.
