Reversal-tolerant Catalyst Layers

Fuel cells present a promising technology for providing clean, efficient electric power in a variety of applications. They are the most environmentally friendly alternative to internal combustion engine technology in vehicles. They also have applications in portable electronics, as well as distributed and back-up power. The last few years have witnessed a tremendous increase in the research and development of fuel cells, including the development of new materials, new system designs, and new operating methods. While many breakthroughs have been made, technical and economic barriers for commercialization still exist. For a polymer electrolyte membrane fuel cell (PEMFC) – the most promising fuel cell technology – to be used commercially in stationary or transportation applications, cost and durability are the major challenges. In transportation applications, fuel cell technologies face more stringent cost and durability requirements: a fuel cell system needs to cost less than $50/kW with a 5,000 hour lifespan (150,000 miles equivalent) and have the ability to function over the full range of vehicle operating conditions (–40 to +90 °C). For stationary applications, a fuel cell system operating on natural gas needs to achieve 40% electrical efficiency and 40,000 hours durability at $750/kW [1]. To be commercially viable, however, fuel cell systems must also exhibit adequate reliability in operation, even when the fuel cells are subjected to conditions outside the preferred operating range. As PEMFCs approach commercialization, significant progress is being made towards producing systems that achieve the optimum balance of cost, efficiency, reliability, and durability.