Development and modelling of optimised solar cells for Mars surface conditions

Nowadays, the solar cells for space applications, designed to provide highest performance values at end of life (EOL) conditions under a constant Sun spectrum, are used without modification also for missions on Mars surface where the spectral conditions differs significantly from the typical space missions ones. As part of the solar cell optimization process, the comparison of the existing AZUR 3G30 and AZUR 4G32adv solar cells performance under various Martian conditions together with the analysis of possible improvements highlights that the AZUR 4G32 cell has a better potential than AZUR 3G30. The optimized AZUR 4G32 developed for Mars conditions and presented in this paper shows an increase of around 5% with respect to the current 4G32adv and 13% with respect to 3G30 cell under the selected reference conditions. Even higher performance boosts are presented under other Martian conditions. Characterization (Spectral Response and Dark I-V) performed on the optimized AZUR 4G32 structure in the temperature range -150 °C ÷ + 50 °C allows to extract the parameters needed for a 2-diode model. The validation of the extracted parameters shows low deviation between measured and calculated dark IV curves. Comparisons of measured and calculated light IV curves for the five Martian scenarios show good agreement confirming that the model allows for the calculation of the solar cell performance under any illumination and temperature conditions on the Martian surface.