Mark Koslowske

Electrochemical Impedance Spectroscopy of Liquid Tin Anode Solid Oxide Fuel Cell

SOFCs present several advantages over other fuel cell technologies, such as their high efficiency of converting the chemical energy into electricity, the ability to use hydrocarbon fuels instead of hydrogen, no noble metals are used in the cell, and they provide a source of high quality heat that can be used for steam generation. Thomas Tao developed a liquid tin anode solid oxide fuel cell (LTA-SOFC) that operates on high sulfur content fuels, such as jet propellant 8 (JP-8). 3 In typical SOFCs the oxidation of the fuel takes place at the interface of the electrolyte and the electron conductor; however, in a LTA-SOFC tin is oxidized at the electrolyte-liquid metal interface, the tin oxide diffuses through the liquid tin to the liquid-tin fuel interface where the fuel is oxidized, and the tin oxide is reduced to liquid tin, as shown in Figure 1. Thus, the LTA-SOFC separates the oxidation of the fuel from the anode of the SOFC eliminating the potential detrimental effects of sulfur. Despite the abundance of literature studying the electrochemical impedance of SOFCs, the literature does not address the anode half of the liquid tin anode solid oxide fuel cell. 4-7 This work develops a first principals model of the electrochemical impedance of a liquid tin anode solid oxide fuel cell anode half cell. Equation1 is used to estimate the Ohmic resistance ( LTA YSZ R R + ),