The interconnection of the cells that make up a solar panel is a simple step, but it is not unimportant. The panels are made up of cells in series, so that a poorly connected cell can spoil the good performance of the entire panel. Back-contact solar cells have polarity connections on the back, making interconnection critical. In this work contact failures are intendedly induced, solar cells are biased at several conditions and electroluminescence measurements are carried out to detect problems. The results show that even at low amperage, connection faults can be identified by simple image processing. As a conclusion, this detection method could be implemented before encapsulating the panels, avoiding efficiency losses.
Mateos et al. (Tue,) studied this question.