The long-term durability of photovoltaic modules is paramount for the continued growth of the industry. Polymer backsheets are of particular concern since they provide electrical insulation and an environmental barrier. In this study, 23 freestanding, multilayer backsheets with nine unique material combinations underwent four different weathering exposures under accelerated and real-world conditions. Besides changes in color and gloss, the induced degradation included parallel or mudflat cracks on 11 backsheets, sometimes in combination with delamination or blistering. Similar degradation has been observed in previous studies and is concerning since cracks compromise the mechanical integrity and electrical safety of backsheets. Quantitative parameters are desirable to reliably classify categories of cracks and supply unbiased features for statistical analysis in predictive lifetime models. We developed an analysis technique that utilizes surface profilometry data to quantify the depth, width, area, spacing, and number of cracks. Parameters are automatically extracted from the raw data by an algorithm running on a high performance distributed computing cluster. Our algorithm excelled at characterizing parallel cracks with minimal de-adhesion, and only an estimated 4% of crack detections were false positives. The addition of humidity and temperature variation formed up to three times as many cracks on a photodose basis compared to dry, constant temperature exposures. Cracks in real-world and accelerated exposures propagated to similar depths with equivalent photodoses; however, the number of cracks formed in accelerated exposures was far greater on a photodose basis. Of samples that cracked, the best performing backsheet configuration was polyvinyl fluoride/poly (ethylene-terephthalate)/polyethylene (PVF/PET/PE) while the least durable was PET/PET/ethylene-vinyl acetate. None of the six PVF/PET/PVF backsheets cracked in any of the exposures.

光伏模块的长期耐用性对于行业的持续增长至关重要。聚合物底片是特别令人关注的，因为它们提供了电绝缘和环境屏障。在这项研究中，具有9种独特材料组合的23种独立式多层背板在加速和现实条件下经受了四种不同的耐候性暴露。除了颜色和光泽变化外，诱发的降解还包括11个底片上的平行或泥滩裂纹，有时还伴有分层或起泡。在以前的研究中已经观察到类似的降解，并且由于裂纹损害了背板的机械完整性和电气安全性而引起关注。需要定量参数来可靠地对裂纹类别进行分类，并为预测寿命模型中的统计分析提供无偏特征。我们开发了一种分析技术，该技术利用表面轮廓测量数据来量化裂缝的深度，宽度，面积，间距和数量。通过在高性能分布式计算集群上运行的算法，可以从原始数据中自动提取参数。我们的算法擅长以最小的去粘力来表征平行裂纹，并且估计只有4％的裂纹检测为假阳性。与干燥，恒温暴露相比，光剂量下增加的湿度和温度变化形成的裂缝多达三倍。现实世界中的裂缝和加速曝光以等效的光剂量传播到相似的深度；然而，基于光剂量，加速曝光中形成的裂纹数量要多得多。在开裂的样品中，表现最佳的底片构造是聚氟乙烯/聚对苯二甲酸乙二酯/聚乙烯（PVF / PET / PE），而耐久性最差的是PET / PET /乙烯-乙酸乙烯酯。六个PVF / PET / PVF底片在任何曝光中均未破裂。