Modeling of Hysteresis in Perovskite Solar Cells: An Overview

Perovskite solar cells are currently the most rapidly emerging photovoltaic technology showing a true potential to lead the commercial solar cell market with efficiencies reaching up to 25.8%. It has cheaper fabrication costs compared to silicon and other photovoltaic technologies due to low-cost solution processing. In spite of such advantages, this technology is still hindered by numerous challenges. The most predominant limitation is the device instability caused due to hysteresis in its J-V characteristics, leading to ambiguous efficiency estimation during actual performance. Extensive research is going on the study and elimination of this problem. The origin of hysteresis in perovskite solar cells is attributed to four main reasons – capacitive effects, ferroelectric polarization, ion migration, and charge trapping. Modeling of hysteresis in perovskite solar cells is one way to reduce this ambiguity in efficiency determination by bringing in some amount of predictability. There are multiple approaches for modeling hysteresis in perovskite solar cells. These approaches include analytical models and equivalent circuit models. In this chapter, the equivalent circuit models developed by considering the reasons behind the origin of hysteresis are summarized and explained so as to give the reader a better understanding about the device as well as the development of models from its device physics.