Empirical Estimation and Analysis of the Dark Ideality factor ‘n’ of single c-Si and c-GaAs Solar cells at Different Sun Irradiation

摘要

The dark ‘n’ value of an illuminated single p-n junction solar cell is a critical parameter that influences the overall performance of the cell. We have estimated the dark ‘n’ values of single cells of c-Si and c-GaAs using an empirical approach by combining measured data of the cells with a simple and straight forward One Diode PV model of a single p-n junction solar cell. Results obtained suggest that the dark ‘n’ values of c-Si cells are larger than that of c-GaAs cells at 1 Sun illumination. The ‘n’ values for both types of cells increase when the illumination is reduced to 0.95 Sun. Our measurements also predict External Quantum Efficiency (EQE) of both cells indicating contributions at each wavelength of the illumination consistent with the bandgap of Si and GaAs.