Optical and Laser Diagnostics for Molten Carbonate Fuel Cells

Molten-carbonate fuel cells (MCFCs) operate at 650°C and 0.1-1 MPa. MCFCs generate electrical energy through the conversion of the fuel gas (either natural gas or coal gas) using an electrolyte of molten carbonate with nickel electrodes. Because of the heat and the corrosive nature of the carbonate and gases, traditional diagnostics are not applicable. We have developed several diagnostics that can be used in such cells for in-situ measurements. We demonstrated CARS as an in-situ detector for major species, especially CO2, in a MCFC. Measurements of CO2 concentrations over a cell give a spatial measure of the operation and efficiency of the cell. We have also demonstrated laser-induced breakdown spectroscopy and photo-fragment spectroscopy as viable techniques for studying the gaseous alkali halides and alkali hydroxides that form as a result of chlorine contamination in the feed gas. We will also talk about our work on a HC1 monitor for the feed lines.