Development of solid oxide fuel cells utilizing alternative fuels.

摘要

This dissertation is a summary of four solid oxide fuel cell (SOFC) research projects which addressed a number of SOFC technologies to use alternative fuels (other than H2, natural gas, and CO) and culminated in the development of a solid oxide fuel cell (SOFC) anode design that is shown to generate electrical power by the oxidation of solid hydrocarbon fuel (coal) without external reformation.;Chapters 1 and 2, demonstrate the current state and limitations of SOFC operation on alternative hydrocarbon fuel sources. A common limitation in traditional SOFC systems is the inability to directly oxidize heavy liquid hydrocarbons due to carbon deposition coking or solid hydrocarbons due to fuel transport limitations. External reformation (Chapter 2) is oftenly used to overcome these limitations but at the cost system efficiency due to the chemical energy consumed in the reformation process.;The contribution to the science and technology of electrochemistry presented here is the development of a liquid metal anode solid oxide fuel cell (LMA-SOFC) system capable of generating electrical power from the direct electrochemical oxidation of coal; as well as the development of a test system and protocol for the performance evaluation of new liquid metal or liquid alloy anode materials. Chapters 3 and 4 present the development and operation of the LMA-SOFC system and test procedure. The LMASOFC system developed is shown to generate electrical power from hydrogen and coal, and is evaluated with electrical impedance spectroscopy and equivalent circuit modeling to further understand the chemical and electrochemical reaction mechanism. The system also identifies the durability of anode materials in high current operation.