A group of researchers from Finland’s Aalto University has found that most stability tests conducted on perovskite and dye-sensitized solar cells are being performed inadequately.
The research team claims that the kinds of tests most commonly conducted currently lack common standards and are frequently not conducted in real-world conditions nor across groups of several cells.
Overall, 261 aging tests were analyzed. “In about half of the aging studies, the data was published only for one solar cell. Studying only one cell does not yield a sufficient amount of data to reliably compare how different materials age, that is, lose efficiency over time,” said one of the research’s author, Armi Tiihonen.
Other shortcomings in current tests were also found by the research team, which stressed that only a third of tests reported the intensities of visible and UV light, humidity and temperature; and that around 52% of tests didn’t even mention the intensity of UV light.
On top of this, the Finnish scientists have discovered that only half of the tests were performed uniquely in dark conditions, with only 15 tests being conducted outdoors. Furthermore, they revealed that only three tests were made using modules comprising several cells connected together.
“’The field needs common standards. High-quality, well-reported and standardized tests would reinforce the confidence of industry and investors in the technologies,” said the research’s coordinator Kati Miettunen.
The research group is now planning to organize a series of conferences to invite other specialists for establishing common guidelines and standards for aging tests.