Post-Test Evaluation of the Oxygen Electrode from A Solid Oxide Electrolysis Stack and Electrode Materials Development

摘要

Steam electrolysis is a high-efficiency process that generates hydrogen from water using electricity and heat from an advanced nuclear power plant. The process depends on multiple ceramic cells arranged in “stacks” identical to solid oxide fuel cell designs, but operating with a reverse current flow. The stack provides for a manageable voltage/current input as well as a manufacturable cell size. However, increased cell area and a multiplicity of components in the stack introduce potential sources of defects that can lead to materials, structural, and performance degradation. A recent paper from Idaho National Laboratory reports the results of a 1000-h test of a Ceramatec 25-cell HTSE stack. The stack, which had generated hydrogen at a nominal rate of 200 Nl/h, experienced an overall performance degradation of ～20% over the duration of the test.