SPLTRAK Abstract Submission
Overall Performance Losses and Activated Mechanisms in Double Glass and Glass-backsheet Photovoltaic Modules with Monofacial and Bifacial PERC Cells, under Accelerated Exposures
Jiqi Liu1, Sameera Nalin Venkat1, Jennifer L. Braid2, Xuanji Yu1, Brenton Brownell4, Xinjun Li4, Jean-Nicolas Jaubert3, Kaushik Roy Choudhury5, Laura S. Bruckman1, Roger H. French1
1SDLE Research Center, Materials Science Department, Case Western Reserve University, Cleveland, OH, United States
/2Sandia National Laboratories, Albuquerque, NM, United States
/3CSI Solar Co. Ltd., Suzhou, China
/4Cybrid Technologies Inc., Suzhou, China
/5DuPont, Electronics and Imaging, Shanghai, China

The long-term reliability of photovoltaic modules is essential to lower the levelized cost of electricity and is dependent on the packaging materials and exposed conditions. EVA or POE encapsulant with backsheet or glass for the rear side in both monofacial and bifacial modules are popular packaging strategies in the market of photovoltaic modules currently. But the quantitative reliability performance data with the statistical significance to compare these packaging strategies are not available currently. In this paper, we compared the characterization results of double glass (DG) and glass-backsheet (GB) minimodules fabricated using different encapsulants under modified dampheat (mDH) with or without full-spectrum light (FSL) of up to 2,520 hours. The characterizations included current-voltage curves, Suns-Voc curves, electroluminescence and photoluminescence images. Using features extracted from current-voltage curves and Pseudo current-voltage curves, the GB monofacial module with rear opaque EVA encapsulant and the DG bifacial module with POE encapsulant were found to have an average power loss that is significantly greater than that of the stable group, which were formed by the module type with an average power loss less than 5% after exposure. The power loss was mostly due to the corrosion indicated by the series resistance increase. Different module types showed varied sensitivity in the series resistance increase when replacing the exposure time from mDH to FSL. The change in the maximum power of Pseudo current-voltage curve and short-circuit current concentrates on several module types and is much less than that in series resistance in general, with the maximal decrease around 1.3% and 2.3%, respectively.