Investigating carbon-capturing getter anode design using a fast computational tool

Abstract

Solid Oxide Fuel Cells (SOFCs) are a promising technology in the power-generation sector because of their ability to use either hydrocarbons or pure hydrogen. However, introducing hydrocarbons to SOFCs has the negative effect of poisoning the anode of the SOFC with carbon molecules. These carbon deposits in the anode place mechanical stress on the anode and crack the anode interrupting the nickel-based electron percolation network. Gradual interruption of this network increases anode electrical resistance and can eventually lead to complete SOFC functional failure. However, one technology that may reduce premature anode failure due to carbon deposition is the use of a getter anode. A getter anode intercepts the carbon prior to deposition on the functional anode. In this work, A CFD model was modified to incorporate a getter anode, and the functional anode in the study saw a roughly 60% drop in carbon deposition with the addition of a 0.1mm getter anode, compared to the baseline. Also a trend was found that total carbon deposited on the functional anode decreased as the porosity of the getter anode decreased. However, lengthening the getter anode and decreasing its porosity can potentially starve the functional anode of hydrogen fuel, so a tradeoff exists removing carbon and maintaining fuel cell performance.