Loss Analysis of Halide Perovskite Solar Modules using Biased Photoluminescence

Perovskite halide semiconductors hold great potential as a low-cost, efficient technology for photovoltaic energy conversion. To advance perovskite materials toward a viable commercial solution, it is important to deconstruct the photophysical mechanisms of performance loss that arise in integrated perovskite solar modules. Perovskite modules typically consist of dozens of small solar cells connected in series, making the operating parameters and performance of each individual cell hidden variables. In this work, we present a method employing biased-photoluminescence imaging to extract the sub-cell current-voltage (I-V) characteristics within perovskite mini-modules. By treating the luminescence image under the reciprocity principle as a spatially-resolved voltage image across the module, the approach enables modeling of the sub-cell voltage distribution. With these voltage images and externally measured global current values, we reconstruct the I-V curves of individual sub-cells.

This modeling of luminescence images enables the determination of: (1) the impact of defects in sub-cells on module photovoltaic performance, (2) the effect of spatial non-uniformities among sub-cells, and (3) the influence of scribe lines on module performance. Overall, we explore the limitations of existing spatially resolved single-cell models and propose novel methods to improve the extraction of local cell performance data from luminescence images of perovskite solar modules.