Damp Heat Aging Analysis of Shingled PV Modules

Shingled module technology has emerged as a promising advancement in photovoltaic (PV) design, offering reduced resistive losses, improved shading tolerance, and higher packing density. However, the durability of these modules under environmental stressors remains a critical concern. This study evaluates the performance and reliability of a shingled N-Type monocrystalline PV module subjected to damp heat (DH) testing per IEC 61215 standards. While the IEC standard specifies testing durations of up to 1000 hours, this test was extended to 4000 hours to provide deeper insights into long-term durability. The module was exposed to 85°C and 85% relative humidity for up to 4000 hours, with performance assessed through Electroluminescence (EL) images, I-V curves, and electrical parameters at regular intervals. Results show progressive degradation, with power output declining by 11.5% and the fill factor dropping by 8.5% after 4000 hours, largely due to moisture ingress causing internal corrosion and interconnection failures. EL images highlighted significant changes at the cell interface while I-V curves demonstrated a stable open-circuit voltage but notable declines in fill factor and maximum power point. These findings underscore the importance of advanced encapsulants and adhesives to improve module durability and suggest further research integrating combined stress tests to evaluate long-term reliability comprehensively.