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Fuel Cell Breakthroughs, Part 1 Work at Los Alamos in the last 25 years has been enabling for the emerging fuel-cell industry, and the Laboratory holds several seminal patents required by would-be product developers. Arguably, the breakthrough that brought the PEM fuel cell out of the space program and made possible its consideration as a ubiquitous power-conversion technology was our development in the late 1980s and early 1990s of the low-platinum PEM electrodes. Before these developments, state-of-the-art PEM “electrodes” had relatively large platinum particles embedded (basically, rammed) directly into the membrane. To maintain electron conductivity, those electrodes required very large amounts of platinum. The sootlike carbon particles did not conduct ions very well, and in the absence of a liquid electrolyte, most ions had no conducting path to the membrane. The Los Alamos breakthrough came when Ian Raistrick applied a solution that contained dissolved Nafion material to the surface of the porous electrode. Once the solution dried and the electrodes were pressed to the membrane, the Nafion material provided an ionconducting path from the PEM to the platinum particles. Mahlon S. Wilson later invented methods for fabricating repeatable thin-film electrodes bonded to the PEM membrane—the so-called membrane electrode assembly (MEA). In combination, these techniques have dramatically lowered the required precious-metal catalyst loadings by a factor of more than 20 while simultaneously improving performance. They are now used by fuel-cell manufacturers and researchers worldwide.
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