Fuel cell vehicles submarines

It is clear that conventional metal hydride hydrogen storage is not a feasible option for storage of land or air vehicle propulsion fuel. However, metal hydride hydrogen storage has been successfully employed on the German, Class 212, fuel cell-powered submarine, where very long underwater endurance is not required. 

PEM Proton-exchange-membrane fuel cell (Polymer-electrolyte-membrane fuel cell) Proton- conducting polymer membrane (e.g., Nafion ) H+ (proton) 50-80 mW (Laptop) 50 kW (Ballard) modular up to 200 kW 25-=45% Immediate Road vehicles, stationary electricity generation, heat and electricity co-generation, submarines, space travel... 

AFC Alkaline fuel cell 30-50% KOH OH- (hydroxide) 60-90 7kW (Apollo) 37-s42% Immediate Space travel, road vehicles, submarines... 

For closed-cycle applications, such as for spacecraft, submarines, or transportation vehicles, the combinations of lightweight, reasonable power density, and compact size are favorable features in comparison with equivalent-capacity battery-based systems. In the International Space Station, for example, both electricity and water are provided by fuel cells. Fuel cells have not only been used in space exploration, but also in submarines (because they generate no noise or vibration). They have also been used to recover the energy from methane that is generated by wastewater, by garbage dumps, and more recently in automobiles as an alternative to the IC engine. 

The PE MFC has a solid ionomer membrane as the electrolyte, and a platinum, carbon-supported Pt or Pt-based alloy as the electrocatalyst. Within the cell, the fuel is oxidized at the anode and the oxidant reduced at the cathode. As the solid proton-exchange membrane (PEM) functions as both the cell electrolyte and separator, and the cell operates at a relatively low temperature, issues such as sealing, assembly, and handling are less complex than with other fuel cells. The P EM FC has also a number of other advantages, such as a high power density, a rapid low-temperature start-up, and zero emission. With highly promising prospects in both civil and military applications, PEMFCs represent an ideal future altemative power source for electric vehicles and submarines [6]. 

Because they are very quiet, and because they are inherently more efficient than diesel or other i.c. power plants, fuel cells have long been regarded by the navies of the United States, Germany, Canada, Australia, and Sweden as an attractive means of propelling small submersibles (such as unmanned underwater vehicles used for marine research, pipeline repair, salvage, and exploration), and even full-size submarines. 

Despite many successfully specialized applications of fuel cells, such as UAV (unmanned aerial vehicles), submarines and the Apollo and Shuttle space missions [1-5], these applications are not the primary markets for fuel cell and hydrogen industries. To date the cost and quality of fuel cells are not comparable to those of the 1C engines or gas turbines. 

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