Mechanistic Insights to Degradation of PERC Minimodules with Differentiated Packaging Materials & Module Architectures

In this paper, we study the degradation behavior of glass-backsheet (GB) and double glass (DG) multicrystalline silicon monofacial PERC minimodules, fabricated using polyolefin elastomer (POE) and ethylene vinyl acetate (EVA) encapsulants, undergoing exposures of modified damp-heat (80°C / 85% RH), with and without full spectrum light. The completed exposure time, at this time, is 1512 hours with each step of 504 hours. Stepwise measurements are conducted throughout exposures including current-voltage (I-V) curves, Suns-V
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, electroluminescence (EL) images, and four-point proof loading with EL for tracking changes in mechanical properties in encapsulants by cell fracture probability. The results show that GB minimodules of both encapsulants, compared to DG minimodules, experience more changes in features of I-V and Suns-VYXC1-00090-A604 measurements. There is no development of PV cell cracking during proof loading as seen from EL images and the load versus load line displacement plots currently.