Abstract

Solid Oxide Fuel Cells (SOFCs) are becoming a popular choice for meeting energy requirements of the present day due to their high efficiency and reformation capabilities. SOFCs are made of ceramic oxides with well-defined physical and thermal properties enabling a high operating temperature range (600-800°C). Efficiency of a SOFC is typically well represented by its output voltage. Resistances across various compo- nents of the SOFC viz. anode, electrolyte and cathode diminish the maximum output voltage thus directly affecting the efficiency of the fuel cell. Each of the layers in a SOFC has generic as well as specific re- quirements warranting specialized fabrication processes. While such processes are many in number, they face limitations on size of the particles usable for the process, cost, ability to create graded porosity, thick- ness, etc. The main thrust of this work is the employment of a novel direct-write tool, namely the Optomec Aerosol Jet deposition system for fabricating the electrolyte layer of a SOFC that addresses some of the practical limitations of traditional SOFC fabrication techniques. While Optomec's Aerosol Jet deposition technique has been employed in several applications including printed electronics, a structured approach to identifying process parameters for printing materials was not found in literature. This work identifies and models process parameters significant to the deposition of nano- crystalline ceria with thickness of the deposited layer as response variable through design of experiments. Initial feasibility tests determined printability of the test ink and established a working range for the desired process parameters under investigation. A full factorial design with five factors and two levels was executed as the screening design. Three of five factors were determined as significant from the screening experiments. A regression equation was generated with the three significant terms from screening. Validation runs exe- cuted indicated lack of curvature within the design space for the significant parameters. Coefficients of terms from the regression equation were updated after regression analysis of a higher order design of experiments with three levels and the three significant parameters from screening. The updated regression equation provides a model with a reduced standard error and better fit of residuals as compared to the model from screening. A brief study on drying methods post-deposition and its impact on the quality of the printed film is also presented in this work.

Library of Congress Subject Headings

Solid oxide fuel cells--Design and construction; Thin films--Design and construction; Cerium oxides

Publication Date

8-24-2012

Document Type

Thesis

Department, Program, or Center

Industrial and Systems Engineering (KGCOE)

Advisor

Cormier, Denis

Advisor/Committee Member

Esterman, Marcos

Comments

Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TK2933.S65 B35 2012

Campus

RIT – Main Campus

Download

Share

COinS