Damp Heat, Temperature Cycling and UV Stress Testing of Encapsulated Perovskite Photovoltaic Cells

Despite concerns about environmental and mechanical stability, perovskite solar cells (PSC) were made stable with careful solar cell design and encapsulation. Replacing methylammonium cations with a mixture of cesium and formamidinium and using an ITO protective contact enabled 140°C encapsulation and enhanced moisture stability. Vacuum laminating mechanically fragile PSCs using glass and a low elastic modulus encapsulant with a butyl rubber edge seal around the perimeter enabled them to pass the IEC 61215 200 temperature cycling and the 1000-hour damp heat test at 85°C85% relative humidity. Removing TiO
₂
from the PSC stacks also resulted in the encapsulated PSCs passing the UV exposure test.