Researchers from Swansea University and Åbo Akademi University have made a breakthrough in solar cell technology by creating a new model that improves the understanding and performance of thin-film photovoltaic (PV) systems. The study was published in the journal PRX Energy.
For almost 80 years, the Shockley diode equation has described how solar cells work. However, recent research questioned this conventional wisdom for certain next-generation solar cells, specifically those using thin films. These flexible and inexpensive solar cells have low efficiency due to several issues that current models cannot account for.
The new study shows that these solar cells achieve maximum efficiency by finding a balance between capturing energy from light and reducing losses from electrical charges canceling each other out.
Our findings provide important insights into the mechanisms driving and limiting charge collection, and ultimately the power-conversion efficiency, in low-mobility PV devices.
A key problem with earlier models was that they didn’t account for “injected carriers,” or charges that enter the device through connections. These carriers significantly affect efficiency and recombination. The new model addresses this gap by introducing a diode equation specifically tailored to account for these injected carriers and their recombination with photogenerated ones.
This breakthrough provides a new framework for analyzing material properties, optimizing devices, and creating thinner solar cells and photodetectors with higher efficiency. It can also help train machines for device optimization, which is an important step forward for creating next-generation thin-film solar cells.
Source: https://www.azom.com/news.aspx?newsID=63288