Impact of Both Series and Shunt Resistance

In the presence of both series and shunt resistances, the IV curve of the solar cell is given by;

and the circuit diagram of the solar cell is given as;

Parasitic series and shunt resistances in a solar cell circuit.

To combine the effect of both series and shunt resistances, the expression for FF_sh, derived above, can be used, with FF₀ replaced by FF_s 1. The overall equation then becomes;

where FF_s is given by;

and by combining the above equations, the net equation for FF becomes;

The following calculator determines the effect of R_s and R_sh on the cell fill factor using the same variable definitions as above.

• 1. M. A. Green, Solar Cells - Operating Principles, Technology and System Application. Kensington, Australia: University of NSW, 1992.