Application of Digital Image Correlation for Solid Oxide Cells Deformation Measurement

Solid Oxide technology, which can be operated in fuel cell, electrolyser, and reversible operation under higher round-trip efficiency among hydrogen technologies, can contribute to the implementation of renewable energy storage in the framework of multi-vector renewable based power systems, thus enabling the clean energy transition. The management of these systems requires accurate dynamic models and algorithms, which have to take into account components degradation. Particularly, the high operating temperature, generally in the 700-750°C range, produces relevant thermal stress which represents one of the main causes of solid oxide cells degradation. This paper investigates solid oxide cell surface deformation, proposing the innovative application of digital image correlation technique. A particular speckle pattern technique has been tested for high temperature measurements on cell surface. Specifically, measurements have been acquired with a 10 minutes time step during temperature ramp from ambient temperature up to 750°C and a subsequent cooling ramp down to about 270°C, for a total test duration of more than 20 hours. Temperature ramp rate has been set equal to 1 °C per minute, according to solid oxide cell set up procedure suggested by the manufacturer. Deformation has been detected in both planar directions revealing a maximum value of 1.1%.