Loss Analysis of High-Efficiency Perovskite/Si Tandem Solar Cells for Large Market Applications

The Si tandem solar cells composes of III-V, II-VI, chalcogenide and perovskite top cells and Si bottom cells are very attractive for creation of new markets. The perovskite/Si tandem solar cells are thought to be one of the most promising PV devices because of high-efficiency and low-cost potential. However, efficiencies of perovskite/Si tandem solar cells with an efficiency of 29.8% are lower compared to 39.5% with III-V 3-junction tandem solar cells and 35.9% with III-V/Si 3-junction tandem solar cells. Therefore, it is necessary to clarify and reduce several losses of perovskite/Si tandem solar cells. This paper presents high efficiency potential of perovskite/Si tandem solar cells analyzed by using our analytical procedure and discusses about non-radiative recombination, optical and resistance losses in those tandem solar cells. The perovskite/Si 2-junction tandem solar cells is shown to have efficiency potential of 37.4% as a result of non-radiative recombination loss of 2.3%, optical loss of 2.7% and resistance loss of 3.1%. Although the perovskite/Si 3-junction tandem solar cells are thought to be very attractive because of higher efficiency with an efficiency of more than 42%, decreasing non-radiative recombination loss in wide bandgap perovskite solar cell materials is pointed out to be necessary.