Thermal Behavior of Crystalline Silicon Bottom Cell in a Monolithic Perovskite/Si Tandem Solar Cells

Monolithic Perovskite/Si tandem solar cells represent a promising direction in photovoltaic technology. However, understanding the temperature coefficient is essential for predicting performance and improving the temperature adaptability of these devices under varying weather conditions. This paper conducts a detailed analysis of the thermal behavior of c-Si as a bottom cell in a monolithic Perovskite/Si tandem arrangement, exploring how its behavior differs from standalone configurations. This investigation is carried out through a numerical simulation using SCAPS software. The simulation considers the temperature-dependent bandgap and absorption for both c-Si and perovskite, as well as the temperature effects on series and shunt resistances. Four simulation scenarios were analyzed, 1) as a standalone c-Si solar cell, 2) c-Si bottom cell in perovskite/Si tandem structure with spectrum split at the perovskite bandgap, 3) c-Si bottom cell, considering perovskite temperature-dependent bandgap, and 4) c-Si bottom cell, considering perovskite layer thickness, absorption and its temperature-dependent bandgap. The results reveal that c-Si solar cells in tandem structures experience notable differences in temperature coefficients, especially in the short-circuit and MPP current densities, compared to standalone configurations. This difference is mainly attributed to the spectrum splitting and temperature-dependent perovskite absorption. Splitting the spectrum leads to an increase in the temperature coefficient of J SC from 0.0944% °C ⁻¹ to 0.2539% °C ⁻¹ ; this temperature coefficient reached 0.983% °C ⁻¹ when the top cell layer thickness and perovskite's temperature-dependent bandgap and absorption were incorporated into the analysis. Nevertheless, only a minor variation was observed in the voltage temperature coefficient, for both in standalone c-Si cells and those incorporated as bottom cells in the tandem structure.