Low Cost Materials, Designs, and Manufacturing Processes for Robust Tubular Solid Oxide Fuel Cells (SOFC)

A colloidal processing method for making parts was demonstrated during Phase I as having potential for manufacturing low-cost, higher performance SOFC cathode tubes. This method offers an alternative to more conventional methods, such as extrusion or isostatic pressing. The method is less capital intensive than conventional methods, has potential for being automated and tubes made by the process require much less care in drying and organic burnout. The colloidal processing method involves preparation of a suspension of particles containing a small amount of organics, low pressure injection into a die, solidification in the die by a temperature change, removal of tube(s) from the die, drying and firing to obtain the desired properties of permeability, mechanical strength and electrical conductivity. Both short (8 inch) and long cathode tubes (32 inch) were made during Phase I and a better understanding obtained as to key processing variables. In Phase II, the individual processing steps will be further optimized, scale-up of the process operations and manufacture of tubes for evaluation in an operating SOFC test system. Also, methods for adding coatings and making other tube support components will be evaluated.