High-throughput analysis of the ideality factor to evaluate the outdoor performance of perovskite solar minimodules

The investigation of perovskite solar modules under outdoor conditions could provide insights into device operation and degradation in the field. Velilla et al. report on the potential of the ideality factor to analyse outdoor device performance evolution over time, distinguish between degradation modes and estimate the lifetime. Halide perovskite solar cells exhibit a unique combination of properties, including ion migration, low non-radiative recombination and low performance dependence on temperature. Because of these idiosyncrasies, it is debatable whether standard procedures for assessing photovoltaic technologies are sufficient to appropriately evaluate this technology. Here, we show a low dependence of the open-circuit voltage on the temperature of a MAPbI(3) minimodule that allows a high-throughput outdoor analysis based on the ideality factor (n(ID)). Accordingly, three representative power loss tendencies obtained from I-V curves measured with standard procedures are compared with their corresponding n(ID) patterns under outdoor conditions. Therefore, based on the linear relationship between T-80 and the time to reach n(ID) = 2 (T-nID2), we demonstrate that n(ID) analysis could offer important complementary information with important implications for outdoor development of this technology, providing physical insights into the recombination mechanism dominating performance, thus improving the understanding of degradation processes and device characterization.