Extraction of solar cell series resistance without presumed current–voltage functional form

A new method which does not require presumed current–voltage functional form is proposed for the determination of the series resistance, the shunt resistance, the photocurrent, and the intrinsic current–voltage characteristics of solar cells. This method was applied to analyze a bulk heterojunction organic solar cell. It was found that the extracted intrinsic current–voltage characteristic clearly exhibits a linear hopping current component and a quadratic space-charge limited current component. Furthermore, the reconstructed dark current–voltage curve is found to differ significantly from the measured dark current–voltage curve, revealing the importance of electric field in the operation of bulk heterojunction organic solar cells.