PV Cell Cracks and Impacts on Electrical Performance

Abstract

Cell cracking in PV modules can lead to a variety of changes in the modules operation, with vastly different performance degradation based on the type and severity of crack. In this work, we correlate cell crack metrics in images with current-voltage (I-V) curve features on a sample set of 38 four-cell Al-BSF and PERC mini-modules showing a range of fracture and electrical properties. Impacts of cracking on electrical performance demonstrated in this work include cell shunting and electrical isolation of cell regions, shown with electroluminescence (EL) images and I-V tracing. Cracks and other EL image properties are quantified with algorithmic computer vision techniques, and correlated with I-V properties at the cell and module levels.