NREL’s unencapsulated solar cell—a cell used for testing that doesn’t have a protective barrier like glass between the cell’s conductive parts and the elements—held onto 94% of its starting efficiency after 1,000 hours of continuous use under ambient conditions, according to research published in Nature Energy.
Steve Harvey, Jeffrey Christians, Tracy Schloemer, Bertrand Tremolet de Villers, and Joseph Luther are co-authors of “Tailored Interfaces of Unencapsulated Perovskite Solar Cells for >1000 Hours of Ambient Operational Stability.”
“During testing, we intentionally stress the cells somewhat harder than real-world applications in an effort to speed up the aging,” said Luther, who along with Joseph Berry directed the work titled “Tailored Interfaces of Unencapsulated Perovskite Solar Cells for >1000 Hours of Operational Stability.” “A solar cell in the field only operates when the sun is out, typically. In this case, even after 1,000 straight hours of testing the cell was able to generate power the whole time.”
While more testing is needed to prove the cells could survive for 20 years, or more, in the field (the typical lifetime of solar panels) this study represents an important benchmark for determining that perovskite solar cells are more stable than previously thought.
“This study reveals how to make the devices far more stable,” Luther said. “It shows us that each of the layers in the cell can play an important role in degradation, not just the active perovskite layer.”
Other co-authors of the paper are Jeffrey Christians, Philip Schulz, Steven Harvey, and Bertrand Tremolet de Villers from NREL; and Jonathan Tinkham, Tracy Schloemer, and Alan Sellinger, who work jointly between NREL and Colorado School of Mines.