GOALI: Simple Low Cost Methods for Making Conductive Interfacial Coatings for Solid Oxide Fuel Cells

Tennessee Technological University, Cookeville TN

Investigators

Abstract

Fuel cells are a promising technology for converting the chemical energy stored in fuels such as hydrogen and methanol into useful electrical energy in a clean and environmentally sustainable manner. Fuel cells can be used to power a number of devices, from portable electronics to electric vehicles. One type of fuel cell, referred to as a solid-oxide fuel cell or SOFC, is particularly well suited for use in providing power for transportation applications such as electric cars. Today, solid oxide fuel cells can be manufactured that have excellent performance, but the electrical power output and efficiency of those fuel cells degrade quickly over time. This Grant Opportunity for Academic Liaison with Industry (GOALI) award supports the development of new materials and a new manufacturing technique that can overcome one of the problems leading to this degradation in SOFC fuel cell performance. In particular, failure often occurs at the point at which the electrical wiring is connected to the parts of the fuel cell where chemical reactions take place to create the electric current. In this work, a new method and material for making this electrical connection to the fuel cell will be developed that will greatly increase the operating lifetime of SOFC fuel cells. This project will be conducted as a collaboration between university and industrial partners, which will provide a pathway for commercial application of the scientific advances made in the work. The scientific and societal broader impacts of the project will stem from the wide number of applications fuel cells in industry and society for clean power generation. The award will support training and education of undergraduate and graduate students in an integrated university-industry team environment, and the development of outreach programs directed at K-12 students to stimulate interest in science, technology, engineering, and mathematics (STEM) careers by using fuel cells and electric power production as hands-on demonstration platforms. The goal of this project is to study the fundamentals of a new process in which the electrical interconnect layer at the fuel cell cathode and the porous cathode itself are made in a one-step process that can be simple and inexpensive, thus solving a major problem in SOFC commercial development. In this work, a process will be developed in which the cathode and electric interconnect interface is processed in one step using reactive sintering. This research will be the first attempt to systematically study the mechanistic aspects of environmentally-assisted reactive sintering for synthesis of spinel layers with metallic powders as the starting materials. Such spinel layers could be an ideal interface material at the cathode-interconnect interface. The reactive sintering process will be applied to synthesize a spinel-based dual-layer structure that can serve as both interconnect coating and cathode-side contact layer. The promising dual-layer spinel structures will then be critically evaluated with regard to its applicability as a cathode-interconnect interface. Cost reduction and improvement in long-term stack performance stability afforded by the spinel dual-layer structure will contribute to the commercial viability of the solid oxide fuel cell technology.