Degradation behavior of perovskite solar cells under high-intensity and multi band illumination conditions

: The author investigated the degradation behavior and mechanism of FACs perovskite solar cells under high-intensity (1-7.35 suns) and multi band illumination (ultraviolet, blue, visible light) conditions. The results indicate that the degradation rate of the device is linearly related to the light intensity within the range of 1-4 solar intensities; When there are ≥ 5 suns, the nonlinear acceleration phenomenon is significant, mainly due to the increase of interface defects and intensified ion migration caused by the photothermal coupling effect. The multi band illumination experiment showed that ultraviolet and blue light had the greatest impact on device stability. After 500 hours of ultraviolet light irradiation, PCE decreased by 42.3%, while blue light decreased by 28.6%. Optimized packaging (Opt-Enc-M) combined with water cooling system significantly improves stability, with PCE retention rate exceeding 80% after 1000 hours under 5 solar intensities. The research provides a theoretical basis for standardizing accelerated aging testing and improving device stability.