Reposted from las493energy, authored by ruzica1.
The fuel cells converts chemical energy stored in hydrogen into electrical energy and water as the only products  in a single step, with a significantly higher efficiency (60%) compared to currently used internal combustion engines (around 20%). In addition, if a fuel cell’s exhaust heat is utilized, the total efficiency can be further increased and it is scalable from very small units to very large units. Hydrogen as a fuel source can be produced from water through renewable forms of energy such as sun, wind, water, geothermal energy, and biomass. Therefore, fuels cells would also slow the depletion of the earth’s fossil fuel resources.
Fuel cell schematic design
Development of inexpensive, hydrogen-powered fuel cell for a wide-scale use is held back by technical and economic deadlocks. Main challenge stems from the the cost of production. Many potential fuel cell technologies have been explored and are under development. Polymer electrolyte membrane fuel cells (PEMFC) show promise as potential candidate for the use in the electric car design.  Currently PEMFC utilize carbon black as a support that binds 3-5 nm platinum nanoparticles as a catalyst. 2 It is estimated that about half of the cost of the current fuel cell comes from the catalysts containing noble metals, such as platinum. This is because the catalyst that breaks down oxygen molecules in a fuel cell requires anywhere from 5 to 10 times more platinum than the catalytic converter in current internal combustion engines.  The challenge is being addressed by combining platinum with other elements, such as nickel, that have so far been unsuccessful due to the non-platinum part of the alloy corroding after short periods. However, scientists still believe that nanoparticles are the way to achieve the ultimate goal, because the catalytic reaction happen only at the surface of the material; and the smaller the particle, the larger the surface area it has with respect to its interior volume.
(1) Klebanoff, L. Hydrogen Storage Technology: Materials and Applications; Taylor and Francis Group. LLC, 2013.
(2) Subban, C.; Zhou, Q.; Leonard, B.; Ranijan, C.; Edvenson, H. M.; Disalvo, F. J.; Munie, S.; Hunting, J. Phil. Trans. R. Soc. A 2010, 368, 3243.
(3) Behling, N. Issues: In Science and Technology, http://issues.org/29-3/behling/.