Materials Issues for Solid Oxide Fuel Cells Design

Abstract

Solid oxide fuel cells ( SOFC s) are complex electrochemical devices that convert chemical energy into electrical energy with high efficiency. A single cell contains three basic components, which are a porous anode, a dense electrolyte, and a porous cathode. In order to generate high power for a determined application, the single cells are stacked, thus requiring the use of interconnects and sealants. An important challenge of these devices is the reduction of their operating temperatures for improving materials compatibility between components, reducing energy consumption and time for startup and cooling down, and increasing the durability. Many strategies for lowering operating temperature in SOFC s have been proposed. In comparison to other fuel cell types, an SOFC stack can be designed to operate within a wide temperature range (500–1000°C). Therefore, it is necessary to select the desired operation temperature that is mainly influenced by the specific application, the type of fuel, and the properties of solid electrolyte. It is possible to address the SOFC design from different approaches: selecting materials for each cell component, selecting cell geometry, or selecting stack design. In this article, different alternatives of materials selection, cell geometry, and stack design, depending on the operating temperatures and compatibilities among materials, are presented.

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“…Материалы на основе диоксида циркония, стабилизированные оксидом скандия, показывают высокие значения ионной проводимости и перспективны в качестве твердых электролитов для различных электрохимических устройств, например, твердооксидных топливных элементов [1][2][3][4], электролизеров и сенсоров [5][6]. Мембраны из диоксида циркония, стабилизированного оксидом скандия, позволяют существенно понизить рабочую температуру твердооксидных топливных элементов, что важно для увеличения ресурса их эксплуатации.…”