ENGINEERING DURABILITY OF MICRO-MINIATURE FUEL CELLS

摘要

Durability is a primary concern for fuel cells, and a major concern for fuel cells and fuel cell systems. Durability is not only a requirement, it is an engineering subject with science foundations. Fuel cells involve material systems, some of which operate at elevated temperatures, typically in the 600-1,000°C range for solid oxide fuel cells (SOFCs), for long periods of time, up to 40,000 hours of expected life for stationary power systems, for example. As a result, durability of fuel cell systems has been the subject of much research attention. Generally speaking, durability of fuel cells has typically been approached by focusing on some major failure modes, such as cracking or pin hole formation (mechanical failure), chemical degradation, and microstructural changes such as changes in porosity or grain boundaries. The focus of such work is most often to select materials and avoid failure. But degradation in these (and other) systems is an imperative; one cannot afford to design a system that lasts forever (even if it were possible).