Electrodeposition of Ni∕LaCrO[sub 3] Composite Coatings for Solid Oxide Fuel Cell Stainless Steel Interconnect Applications

Abstract

A major drawback of currently used ferritic stainless steel interconnects in solid oxide fuel cells is the loss of electrical conductivity due to high-temperature oxidation of the steels and the formation of a poorly conductive chromia layer. To overcome this problem, a composite coating consisting of dispersed conductive particles in a Ni matrix has been developed, studied, and optimized. Codeposition was performed using a Watts nickel electroplating bath containing suspended particles. The optimum conditions to maximize the particle volume fraction in the coating were determined to be a current density of , particle loading in the bath, pH 4, and suspension of particles in the plating bath by means of an overhead impeller. For the optimum conditions, a particle volume fraction in the coating equal to was achieved. Oxidation tests showed that the conductive particles are embedded in the oxide layer, and the oxidation growth rate is reduced remarkably compared with pure Ni electrodeposits.