A focus area in SOFC is the development of long-term stable cells and systems. The target is a system with a degradation rate of about 0.25% per 1000 hours, aiming for a total lifetime of the SOFC stack of 40,000 hours. To acheive this, an extensive test program is necessary. We can perform a number of mechanical, microstructural and electrochemical tests to characterize the cells. Long-term and accelerated tests can be made in controlled environments to investigate questions such as durability or robustness to thermal cycling. The tests are performed on both single components (e.g., interconnects), half cells (cells without a cathode), symmetrical cells (electrolytes with cathode layers on both sides), cells and short stacks.
Another important task for the test group is to study the reproducibility of the cells produced in the pre-pilot plant. Detailed studies of the variation in performance of nominally identical cells can identify critical processes in the production. An ongoing evaluation and optimization project has reduced the spread in performance to below 10%.
Test stand for cell testing.
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