Researchers Identify Key Factor for Accelerating Perovskite Solar Cell Aging Tests

Perovskite solar cells (PSCs) hold significant promise for widespread adoption due to their cost-effectiveness and lower energy-intensive production compared to silicon cells. However, achieving the decades-long durability expected for commercial warranties remains a critical challenge. To address this, researchers are investigating accelerated aging tests to predict long-term stability.

A recent study led by Dr. Carolin Ulbrich at HZB and Andreas Bartelt at HTW Berlin compared naturally aged PSCs with those subjected to artificial aging. After 20 months of natural aging under real-world conditions, three primary degradation mechanisms were identified: phase segregation, copper corrosion, and edge patterns. Phase segregation involves compositional changes in the perovskite material leading to the formation of small circular domains.

While elevated temperatures (65–85 °C) are commonly used to accelerate aging, this method was found to introduce an additional degradation mechanism not observed in outdoor-aged samples. The research team explored alternative acceleration methods, finding that increasing light intensity to 2.3 suns effectively accelerated all three identified degradation mechanisms. Crucially, this method preserved the spatial trends observed in naturally aged cells, allowing for a faster assessment of degradation.

While varying electrical bias also promoted phase segregation, it altered the spatial extent of copper corrosion and edge pattern formation, making it less representative of real-world degradation. Although precise lifetime prediction remains challenging, the study concludes that accelerated aging tests are valuable for rapidly screening new materials and cell designs, thereby advancing perovskite technology development. The researchers identified increased light intensity as a key parameter for accelerating the aging process.