On the General Current Dependence of the Distributed Series Resistance of Solar Cells: The Influence of the Base Resistivity

Abstract

The lumped series resistance Rs of a silicon solar cell isn’t constant but depends on the operating point of the solar cell. For describing the relevant current dependence analytically, only few theories exist that can easily be applied to experiments. These are: (i) the ad-hoc modelling by Araújo et al., modified by Breitenstein et al., and (ii) the LR-Rs approach by Wagner et al. Both have fundamental limitations: Whereas Araújo’s ad-hoc model is partly unphysical, the LR-Rs approach misses the influence of the base resistivity. Here, we discuss these shortcomings, and we show where to include the base resistivity in the LR-Rs approach. In addition, we discuss the current dependence of the lumped series resistance of a solar cell in general terms, thereby clarifying the underlying physical basics.