Alkaline Fuel Cell – Applications

Step By Step Process Illustrated

Alkaline Fuel Cell technology Company http://www.astris.ca/ Profile Founded in 1983, “Astris Energi” has steadily developed the alkaline fuel cell (AFC) and become the world’s leading AFC technology company. Through technology breakthroughs, Astris has developed an AFC that has lower material costs than other low temperature fuel cells, in addition to having higher energy efficiency and broad operating capabilities.

Advantages of AFC by Astris Jiri Nor, President and CEO of Astris, helped develop the very first working alkaline fuel cell (AFC) in Canada in 1984. He decided early on that AFC technology had both technical and economic advantages over the proton exchange membrane (PEM )technology that was being pursued by most U.S. companies in the field. NASA and the Russian space program had also chosen AFCs over PEMs to provide electricity, heat and pure water for all manned space vehicles, due to the AFCs greater fuel efficiency

Continued The selection of the alkaline over the PEM and three other types of fuel cells is proving to have been the right choice, as the AFC appears to be positioned to take the lead due to major technology breakthroughs. The AFC was relegated to secondary status in the 1970s despite important attributes because of concerns about cost and lifespan for commercial use. – concerns Astris has now addressed.

Continued The leader in AFC technology, Astris has replaced costly platinum with inexpensive materials as the AFC catalyst and introduced new scrubbing technology to minimize CO2 effects and thereby extend the alkaline fuel cell life beyond that of other fuel cells.

Advantage Points With these and other developments, the AFC has a number of competitive advantages: Low material costs – plastics, carbon, base metals and metal oxides; no platinum. Long life span – 2000-plus hours currently. Superior electrochemical conversion efficiency to other fuel cells and the internal combustion engine. Quick start, even in sub-freezing temperatures down to minus 40 degrees C. Simpler heat and water management when compared to other fuel cell technologies. Like other fuel cells, it is odorless and quiet for enclosed applications

Current Focus Validating the strides made in AFC technology, the US Department of Energy recently renewed an R&D roadmap for the AFC after a 30 year hiatus. AFCs currently in development are most suited to smaller scale applications in the three main energy markets and these are the types of market Astris initially targets: Stationary – such as back up power for communication towers, data centers. Portable – such as prime or auxiliary power for worksites, cottages, boats. Transportation – such as neighborhood electric vehicles, golf cars, fork lift vehicles

ALKANLINE FUEL CELL – TECHNOLOGY FOR THE 21st CENTURY Alkaline cells, just like alkaline based batteries, are reliable performers that can be built inexpensively from down-to-earth materials – carbon, plastic, base metals; they use cheap electrolyte, start instantly and perform even in deep subzero temperatures. They do not depend on expensive platinum catalyst. And one of the alkaline cell problems often quoted by their detractors – their limited tolerance to carbon dioxide – has been solved by engineers many times over. The complete article is in a PDF format and its uploaded in directory “MURU” under the name “AFC-Future.PDF”.

Working Needs : Alkaline fuel cells use an electrolyte that is an aqueous (water-based) solution of potassium hydroxide (KOH) retained in a porous stabilized matrix. The concentration of KOH can be varied with the fuel cell operating temperature, which ranges from 65°C to 220°C. The charge carrier for an AFC is the hydroxyl ion (OH-) that migrates from the cathode to the anode where they react with hydrogen to produce water and electrons. Water formed at the anode migrates back to the cathode to regenerate hydroxyl ions. Therefore, the chemical reactions at the anode and cathode in an AFC are shown below. This set of reactions in the fuel cell produces electricity and by-product heat. Anode Reaction: 2 H2 + 4 OH- => 4 H2O + 4 e- Cathode Reaction: O2 + 2 H2O + 4 e- => 4 OH- Overall Net Reaction: 2 H2 + O2 => 2 H2O

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