Recombination kinetics in a silicon solar cell at low concentration: electro-analytical characterization of space-charge and quasi-neutral regions.

The present work reports a detailed electro-analytical framework for studying commercially available mono-crystalline silicon solar cells under varying illumination conditions to explore their application in the up-and-coming field of low concentration photovoltaics (LCPVs). The effect of low concentration illumination (>1-12 suns) on performance indicating parameters, i.e., short circuit current, open circuit voltage, fill factor, efficiency and ideality factor, was investigated using DC characterization. The same framework can be used for AC characterization in order to explore diffusion capacitance, transition capacitance, diffusion resistance and recombination kinetics under varying illumination. Recent developments in the impedance spectroscopy technique have broadened its horizon and have allowed its use in addressing unexplored material and performance aspects of mono-crystalline Si solar cells under non-equilibrium conditions. The obtained DC and AC experimental results are coupled with theoretical treatment to demonstrate the characteristic features of charge recombination in the space-charge region and the quasi-neutral region.