MOLDED TITANIUM CARBIDE BIPOLAR PLATES FOR HIGH VOLTAGE BATTERY AND FUEL POWER SOURCES

A LACK OF INEXPENSIVE, CORROSION-RESISTANT MATERIALS FOR BIPOLAR PLATES IS A MAJOR HINDANCE TO COMMERCIALIZATION OF MANY ADVANCED ACIDIC ELECTROCHEMICAL SYSTEMS, WHERE ONE OF THE ELECTRODES OPERATES AT A HIGH OXIDIZING POTENTIAL. UNDER THESE CONDITIONS, GRAPHITE, A RELATIVELY LOW COST MATERIAL, IS UNSTABLE. SOME STABILITY IMPROVEMENTS ARE POSSIBLE THROUGH RESIN IMPREGNATION AND HIGH-TEMPERATURE HEAT TREATMENT. HOWEVER, THESE PROCESSES RESULT IN SIGNIFICANTLY INCREASED COST. IN THIS PROJECT, BIPOLAR PLATES MADE FROM CORROSION-RESISTANT TITANIUM CARBIDE (TIC) WILL BE DEVELOPED. IN PRELIMINARY TESTING, SUCH PLATES SHOWED SIGNIFICANTLY BETTER CORROSION RESISTANCE AT OXIDIZING CONDITIONS THAN GRAPHITE. SINCE THE TIC PLATES WILL BE MANUFACTURED USING, A LOW-COST MOLDING PROCESS, COST IS EXPECTED TO BE LES THAN RESIN-IMPREGNATED GRAPHITE PLATES. FURTHERMORE, THE TIC PLATES WILL HAVE HIGHER ELECTRICAL CONDUCTIVITY THAN GRAPHITE PLATES. PHASE I WILL DEVELOP PROCEDURES FOR MOLDING BIPOLAR PLATES WITH DESIRABLE PHYSICAL, CHEMICAL, AND ELECTROCHEMICAL PROPERTIES FOR USE IN ACID-CONTAINING APPLICATIONS UNDER OXIDIZING CONDITIONS. THE EFFECT OF MOLDING CONDITIONS ON BIPOLAR PLATE PROPERTIES AND THE USE OF THE PLATE IN FUEL CELLS WILL BE INVESTIGATED.