Combining Stress Tests Enhances Performance Prediction of Perovskite Solar Cells
During operational stability testing by NREL, the cells retained over 93% of the efficiency
September 13, 2023
Recent findings from a study by the U.S. Department of Energy’s (DOE) National Renewable Energy Laboratory (NREL) emphasize the importance of subjecting perovskite solar cells to a combination of stress tests simultaneously to best predict their real-world functionality.
One of the key takeaways from the research is that outdoor conditions place considerable stress on solar cells, leading to efficiency losses and reduced power production over time.
Solar cells, including those based on perovskite materials, must endure a range of harsh environmental conditions, such as humidity, heat, and varying light levels.
To achieve the reliability required for commercialization, standardized testing protocols must be established to facilitate comparisons and validations among different research groups.
Traditionally, researchers have assessed the stability of perovskite solar cells by subjecting them to individual stress factors, such as exposure to light or low temperatures.
However, these stressors often interact simultaneously, which can significantly accelerate performance degradation or introduce new issues that were not apparent when testing each factor in isolation.
The NREL-led research team conducted a series of tests on perovskite solar cells to replicate real-world conditions more accurately. During operational stability testing, the cells retained over 93% of their maximum efficiency after approximately 5,030 hours of continuous operation.
Thermal cycling, involving temperature fluctuations between -40 and 85 degrees Celsius, showed an average degradation of about 5% after 1,000 cycles.
However, what sets this study apart is its focus on examining how different stressors interact.
It was found that when subjected to a combination of high temperature and illumination, perovskite solar cells experienced the most significant degradation.
This insight highlights the critical importance of considering multiple stress factors in tandem when assessing the outdoor performance of these promising solar technologies.
By identifying the most critical combination of stressors—high temperature and illumination—researchers are taking a vital step closer to harnessing the full potential of perovskite solar cells as a clean and efficient energy source.
Perovskite solar cells have emerged as promising contenders for clean and efficient renewable energy solutions.
However, before these advanced solar cells can find widespread commercial application, researchers must determine how well they will perform outdoors in unpredictable and demanding conditions.
“We must understand how well perovskite solar cells will perform outdoors, under real conditions, to move this technology closer to commercialization,” emphasized Kai Zhu, a senior scientist in the Chemistry and Nanoscience Center at NREL. “That’s why we identified accelerated testing protocols that can be conducted in the laboratory to reveal how these cells would function after six months in operation outside.”
The study led by Zhu, titled “Towards linking lab and field lifetimes of perovskite solar cells,” was recently published in the journal Nature.
Last month, researchers at NREL published a study that reveals how sound waves could play a pivotal role in making solar cells more affordable for earth-bound applications.
In July, NREL claimed to achieve 91%-93% bifaciality on a newly developed bifacial perovskite solar cell.