Fabrication and characterisation of planar and tubular solid oxide fuel cell anodes

Abstract

Solid Oxide Fuel Cells (SOFCs) are energy conversion devices that convert the chemical energy of a fuel directly into electricity and useful heat, where the latter is recovered at the device’s high working temperature. SOFCs have become important in the fuel cell field due to their high energy conversion efficiency, wide range of fuels and environmental friendliness. However, one of the main obstacles to put SOFCs into mass production is their high fabrication costs including the cost of components such as the electrodes – anodes and cathodes. This project investigates the possibility of manufacturing anodes for tubular SOFCs by a novel co-deposition process which can reduce costs compared with conventional fabrication techniques. Anode requires a ceramic phase to help match the coefficient of thermal expansion of the electrolyte and a metallic phase to conduct electrons to the outside circuit. Both of these can be achieved via a novel nickel-ceramic electroless co-deposition technique. Both ceramic and metallic parts of the anode are deposited together in one single process and avoid the expensive sintering process which is involved in traditional techniques. The elimination of multi-stage processing and high thermal consumption reduces the time and cost of the anode fabrication process. The main challenge in this project is to increase the content of ceramic particles embedded in the nickel. The variables investigated are (i) ceramic particle size, (ii) plating time and (iii) the plating performance both on the inside and outside of tubular surfaces. Initial experiments were carried out on planar surface