Diagnosing tandem cells [photovoltaics]

In this paper, the authors report three new diagnostic techniques for identifying problem areas in tandem solar cells. These techniques can be easily extended to diagnosing triple junction solar cells. They applied these techniques to diagnose an a-Si:H based tandem solar cell having an extraordinarily low Voc. As they demonstrated, the assessments of the problem in this cell produced by each of the authors' diagnostic approaches agree well with each other.