Coupled Thermodynamic and Stress–Strain Insights into Textured Perovskite/Silicon Tandem Solar Cells

Perovskite/crystalline silicon (c-Si) tandem solar cells (TSCs) offer exceptional potential for next-generation photovoltaics, yet their complex multilayer structures and thermal-stress mismatches pose significant challenges. Here, we develop a comprehensive coupled opto-electro-thermal-mechanical simulation model to thoroughly investigate the thermodynamic and stress–strain behavior in pyramid-textured perovskite/c-Si TSCs. Our results reveal that energy-dissipation-induced heat significantly reduces the open-circuit voltage and efficiency of the devices, which can be mitigated through effective cooling strategies and minimizing nonintrinsic heat generation. Additionally, we demonstrate that heat predominantly accumulates in the perovskite layer, inducing localized thermal stress, especially at pyramid valleys. We further identify that stress can be significantly alleviated by adopting rounded pyramid structures and incorporating grain-boundary infilling materials engineered for optimal thermal expansion and mechanical compatibility. This work delivers a comprehensive understanding of heat-stress-induced performance degradation in textured TSCs and proposes actionable strategies for heat-stress management, providing valuable insights for developing high-efficiency and stable perovskite/c-Si TSCs.