Describing the light intensity dependence of polymer:fullerene solar cells using an adapted Shockley diode model

Abstract

Solar cells are generally optimised for operation under AM1.5 100 mW cm À2 conditions. This is also typically done for polymer solar cells. However, one of the entry markets for this emerging technology is portable electronics. For this market, the spectral shape and intensity of typical illumination conditions deviate considerably from the standard test conditions (AM1.5, 100 mW cm À2 , at 25 1C). The performance of polymer solar cells is strongly dependent on the intensity and spectral shape of the light source. For this reason the cells should be optimised for the specific application. Here a theoretical model is presented that describes the light intensity dependence of P3HT:[C60]PCBM solar cells. It is based on the Shockley diode equation, combined with a metal-insulator-metal model. In this way the observed light intensity dependence of P3HT:[C60]PCBM solar cells can be described using a 1-diode model, allowing fast optimization of polymer solar cells and module design.

Temperature and Light Modulated Open‐Circuit Voltage in Nonfullerene Organic Solar Cells with Different Effective Bandgaps

“…The range of light intensities I ≈ 10–100 mW cm −2 is the most suitable and commonly used for testing the dominant recombination mechanisms as it is not influenced by leakage losses and enhanced photodegradation. [ 42–49 ] As shown in previous study, [ 50 ] the parasitic effect of the shunt resistance R sh > 10 kΩ cm 2 (that is the case for our devices: R sh ranges from 0.1 to 1 MΩ cm 2 ) becomes negligible at light intensities I ≥ 10 mW cm −2 since the flux of photogenerated charge carriers significantly exceeds the leakage and thus does not result in errors during the fitting of the experimental data. Light intensities >100 mW cm −2 may result in a significant enhancement of photodegradation processes, rendering any effort to model the recombination dynamics under these conditions pointless.…”

Reversible degradation in ITO-containing organic photovoltaics under concentrated sunlight

“…[1][2][3][4][5][6][7] Removal of expensive indium tin oxide (ITO) from the architecture of organic solar cells contributes towards further decreasing the manufacturing cost. Substitution of ITO by a composite electrode, containing highly conductive PEDOT:PSS and current collecting grids, [8][9][10][11] was demonstrated to produce large area devices without efficiency losses and allow solution processing of the bottom electrode. The latter is more cost-efficient in comparison with vacuum deposition of ITO.…”

Integrated Front–Rear-Grid Optimization of Free-Form Solar Cells

“…14 is reduced by a certain factor. For a OPV, photocurrent is observed to be voltage-dependent [31][32][33] and this behavior is especially prominent in the reverse regime. Since our model uses the data only for a small range of positive voltage values, we assume that photocurrent is independent of voltage.…”

“…However, for organic solar cells, Eq. 1 does not fit very well [31][32][33]. While modeling, this needs to be taken into account and the behavior of the device needs to be accurately modeled.…”