Matching of Silicon Thin-Film Tandem Solar Cells for Maximum Power Output

摘要

We present a meaningful characterization method for tandem solar cells. e experimental method allows for optimizing theoutput power instead of the current. Furthermore, it enables the extraction of the approximate AM1.5g efficiency when workingwith noncalibrated spectra. Current matching of tandem solar cells under short-circuit condition maximizes the output current butis disadvantageous for the overall ll factor and as a consequence does not imply an optimization of the output power of the device.We apply the matching condition to the maximum power output; that is, a stack of solar cells is power matched if the power outputof each subcell is maximal at equal subcell currents. e new measurement procedure uses additional light-emitting diodes as biaslight in the characterization of tandem solar cells. Using a characterized reference tandem solar cell, such as a hydrogenatedamorphous/microcrystalline silicon tandem, it is possible to extract the AM1.5g efficiency from tandems of the same technologyalso under noncalibrated spectra.