The paper presents a comprehensive study on the thermal shock (TS) resilience of perovskite solar cells (PSCs) for space applications. The authors propose a novel accelerated TS protocol that better simulates the rapid temperature fluctuations experienced in low Earth orbit (LEO). Using FAPbI₃ as a model system, they investigate the effect of MAPbBr₃ doping on phase stability and device performance. The study is further validated through a high-altitude balloon (HAB) test bridging lab-scale testing with near-space environmental conditions. I believe that the paper is appropriate for publication in EES.
Here are some comments:
1. The TS protocol they developed has a higher ramp rate than the HAB test. While both tests identify the 5% sample as more stable, the HAB test was performed under far less extreme conditions. Given this discrepancy, an explanation as to why the HAB test is still considered an appropriate validation for the TS protocol would be helpful.
2. There are two conflicting data availability statements. On page 20, it is noted that “Obtained results are not shared”. A few pages later, there is another statement that reads “All data supporting the findings of this study, including J–V characteristics, EQE spectra, photoluminescence, and structural analyses (XRD, SEM), are available from the corresponding author upon reasonable request. The data will also be deposited in the UNSW Research Data Repository following publication.” Please clarify.
3. When comparing the stability of the doped devices, it would be helpful if there was some discussion about the stability of devices under terrestrial long term conditions. Does TS yield any surprising results in terms of stability? What percentage samples are most stable under terrestrial conditions?

I believe that the authors have addressed the concerns raised by the reviewers.