Thermodynamic limit of tandem solar cells under different solar spectra and their perovskite top solar cell

摘要

Thermodynamic (detailed balance) limits of single-junction and tandem-type solar cells are calculated under different solar spectra, which are spectra of blackbody (6000 K), air mass 0, air mass 1.5 global (1.5G), and air mass 1.5 direct (1.5D). The solar cells are described by blackbody under room temperature of 298.15 K. It is disclosed that optimized bandgaps of single-junction solar cells with the highest conversion efficiencies of 31.6, 30.6, 33.7 and 33.1% are 1.29, 1.25, 1.34, and 1.34 eV under illuminations of blackbody (6000 K), air mass 0, air mass 1.5G, and air mass 1.5D, respectively. Conversion efficiencies of 43.2, 42.2, 45.5, and 45.1% are further increased for double-junction tandem solar cells with optimized bandgaps of bottom and top cells under spectra of blackbody (6000 K), air mass 0, air mass 1.5G, and air mass 1.5D, respectively. Moreover, detailed balance limits of tandem solar cells with perovskite top cells with bandgap range of 1.60?1.63 eV were realized with high conversion efficiency, when bandgap values of bottom cells are optimized in a range of 0.8?1.01 eV, and at 1.1 eV. It is also disclosed that the optical matching between top cell absorber and bottom cell absorber should be optimized for the high cell performances.