TY - JOUR A1 - Erdil, Ulas A1 - Khenkin, Mark A1 - Remec, Marko A1 - Emery, Quiterie A1 - Sudhakar, Vediappan A1 - Schlatmann, Rutger A1 - Abate, Antonio A1 - Katz, Eugene A. A1 - Ulbrich, Carolin T1 - Mimicking Outdoor Ion Migration in Perovskite Solar Cells: A Forward Bias, No-Light Accelerated Aging Approach JF - ACS Energy Letters N2 - Perovskite solar cells (PSCs) are expected to transform the photovoltaic market; however, their unproven operational stability requires urgent attention, particularly accelerated aging tests. Currently, illumination is the primary stressor in such tests. In this work, we present an accelerated aging procedure consisting of prolonged forward biasing followed by a dark storage (postbias rest) phase, conducted entirely in the dark. During aging under forward bias, ion migration led to impeded charge transport, macroscopic defect growth, and an adverse response of the cells to short light soaking, all of which recovered in the postbias rest phase, yet resulted in increased recombination due to redistribution of ions. We found that outdoor operation of PSCs in Berlin, Germany, over a 20-month period exhibited similar dynamics, with periods of higher temperature and irradiance (spring-summer) aligning with the forward bias phase and cooler, dimmer periods (fall–winter) aligning with the postbias rest phase. This paves the way for accelerated aging tests that can mimic ion migration-induced degradation outdoors without requiring an illumination source. KW - Perowskit KW - Solarzelle KW - Perovskite solar cells Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:523-20205 SN - 2380-8195 VL - 10 IS - 3 SP - 1529 EP - 1537 PB - American Chemical Society ER - TY - JOUR A1 - Erdil, Ulas A1 - Khenkin, Mark A1 - Bernardes de Araujo, Wander Max A1 - Emery, Quiterie A1 - Lauermann, Iver A1 - Paraskeva, Vasiliki A1 - Norton, Matthew A1 - Vediappan, Sudhakar A1 - Kumar, D. Kishore A1 - Gupta, Ritesh Kant A1 - Visoly‐Fisher, Iris A1 - Hadjipanayi, Maria A1 - Georghiou, George E. A1 - Schlatmann, Rutger A1 - Abate, Antonio A1 - Katz, Eugene A. A1 - Ulbrich, Carolin T1 - Delamination of Perovskite Solar Cells in Thermal Cycling and Outdoor Tests JF - Energy Technology N2 - For the commercialization of perovskite solar cells (PSCs), detection of associated degradation mechanisms and mitigation of their effect is of paramount importance. The former requires outdoor and indoor stability tests to detect these mechanisms under real operation conditions and to accelerate them under controlled environments. Herein, the thermomechanical stability of encapsulated PSCs in outdoor tests at three locations coupled with indoor thermal cycling tests is investigated. Results show that encapsulant‐induced partial delamination can occur in outdoor and indoor tests, leading to disruption in device integrity and substantial loss in the cell active area and short‐circuit current. The findings suggest that delamination involves C60 and SnO2 layers as the mechanically weakest point in the device stack. To the best of our knowledge, this work is the first demonstration of delamination in encapsulated PSCs under real operation conditions. While partial delamination emerged on some of the cells exposed in Israel and Cyprus in just a few weeks, it did not occur in Germany over 2.5 years of outdoor exposure. This highlights the importance of multiclimate outdoor testing to validate the significance of failure modes observed through accelerated indoor testing. KW - Delamination KW - delaminations KW - encapsulations KW - outdoors KW - perovskite solar cells stabilities KW - thermal cycling KW - encapsulation Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:523-19632 SN - 2194-4288 SN - 2194-4296 VL - 13 IS - 1 ER - TY - JOUR A1 - Farias‐Basulto, Guillermo A1 - Kafedjiska, Ivona A1 - Bertram, Tobias A1 - Riedel, Maximilian A1 - Emery, Quiterie A1 - Remec, Marko A1 - Graniero, Paolo A1 - Khenkin, Mark A1 - Kaufmann, Christian A. A1 - Lauermann, Iver A1 - Klenk, Reiner A1 - Schlatmann, Rutger A1 - Ulbrich, Carolin T1 - Perovskite‐CIGSe Tandem Solar Cell: Over One Year of Outdoor Monitoring JF - Advanced Energy and Sustainability Research N2 - Tandem solar cells can surpass the limitations of single‐junction devices, promising increased performance due to lower thermalization losses. Even though many research and industrial upscaling efforts are based on perovskite‐Si tandems, all‐thin‐film photovoltaic (PV) devices, for instance with chalcopyrite (CIGSe) and perovskite, can offer many advantages such as significant cost and material savings and access to niche markets like building integrated‐ and flexible PV. However, long‐term stability and outdoor performance of perovskite‐based tandem devices is to this day challenging. This work presents the first data analysis of year‐round outdoor measurements (mpp‐tracked) of a perovskite‐chalcopyrite tandem device with a starting efficiency of about 23.14% before encapsulation. The maximum outdoor performance of the tandem device changed during the period of observation, reaching the peak performance in April and then decreased due to the device degradation. At its maximum outdoor performance, the tandem could reach up to 68% higher instantaneous power output, relative to its single‐junction reference (CIGSe‐SJ). In addition, a quantitative time series performance analysis, exemplary qualitative imaging characterization of the tandem before and after outdoor exposure, is shown. Finally, the possibility of predicting the immediate performance of an all‐thin‐film tandem is verified by using a multiple linear regression model with accuracies generally exceeding 90%. KW - Machine learning KW - Cu(In,Ga)Se KW - machine learning KW - perovskite KW - solar energy KW - tandem KW - Perovskite KW - Solar energy Y1 - 2025 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:523-22159 SN - 2699-9412 VL - 6 IS - 12 ER -