METAL AND METAL OXIDE CATALYZED ELECTRODES FOR ELECTROCHEMICAL CELLS, AND METHODS OF MAKING SAME

摘要

Porous electrodes for use in fuel cells and other electrochemical cells comprise a non-noble metal catalytically active layer on a porous conductive substrate. The loading of the catalytically active layer is lower in terms of weight of catalyst per unit area of geometrical electrode surface than heretofore. Several alternative methods of forming the electrodes impregnating a porous conductive substrate with a metal salt solution, followed by chemical or thermal formation of the porous catalytically active layer; mixing the catalytically active material of the porous conductive substrate, followed by fabrication of the electrode; or depositing pyrolitic carbon from the gas phase onto a porous conductive substrate, at elevated temperatures in a gas atmosphere. The electrode may have a porous metallic current collector, and a further gas diffusion layer. The electrodes of this invention have particular utility in alkaline primary or secondary cells as auxiliary gas recombining electrodes, especially as oxygen consuming auxiliary transfer electrodes.