Machine learning enhances perovskite solar cell production

In the lab, perovskite solar cells show high efficiency in converting solar energy into electricity. In combination with silicon solar cells, they could play a role in the next generation of photovoltaic systems. Now researchers at KIT have demonstrated that machine learning is a crucial tool for improving the data analysis required for commercial fabrication of perovskite solar cells. Their research findings have been published in Energy and Environmental Science.

Photovoltaics are a key technology in efforts to decarbonise the energy supply. Solar cells based on perovskite semiconductor layers already boast very high efficiency levels. They can be produced economically in thin and flexible designs. “Perovskite photovoltaics is at the threshold of commercialisation but still faces challenges in long-term stability and scaling to large surface areas,” said Professor Ulrich Wilhelm Paetzold, a physicist who conducts research at the Institute of Microstructure Technology and the Light Technology Institute (LTI) at KIT.

“Our research shows that machine learning is crucial to improving the monitoring of perovskite thin-film formation that’s needed for industrial production.” With deep learning (a machine learning method that uses neural networks), the KIT researchers were able to make quick and precise predictions of solar cell material characteristics and efficiency levels at scales exceeding those in the lab.

A Step towards industrial viability

“With measurement data recorded during production, we can use machine learning to identify process errors before the solar cells are finished. We don’t need any other examination methods,” said Felix Laufer, an LTI researcher and lead author of the paper. “This method’s speed and effectiveness are a major improvement for data analysis, making it possible to solve problems that would otherwise be very difficult to deal with.”

By analysing a novel dataset documenting the formation of perovskite thin films, the researchers leveraged deep learning to identify correlations between process data and target variables such as power conversion efficiency.

“Perovskite photovoltaics has the potential to revolutionise the photovoltaics market,” said Paetzold, who heads the LTI’s Next Generation Photovoltaics department. “We show how process fluctuations can be quantitatively analysed with characterisation methods enhanced by machine learning techniques to ensure high material quality and film layer homogeneity across large areas and batch sizes. This is a crucial step toward industrial viability.”

Image caption: Artificial intelligence assists with monitoring and optimising the production of perovskite solar cells. Image credit: Markus Breig, KIT; Felix Laufer, KIT.