Simulation of light intensity dependent current characteristics of polymer solar cells

Abstract

An extended replacement circuit describing the current–voltage characteristics of bulk heterojunction polymer solar cells at different light bias levels is introduced and discussed. A one diode-model is expanded by an extraction model for photogenerated carriers taking into account the effective reduction of the mean distance which the charge carriers cover when sweeping the electrical bias through the fourth quadrant of the solar cell. The model properly describes the current–voltage behavior of bulk heterojunction solar cells over more than three orders in light intensity with one set of parameters.

Light intensity dependence of open-circuit voltage of polymer:fullerene solar cells

“…Using the appropriate values for the electron and hole mobility for an MDMO-PPV:PCBM device, 16 E gap = 1.3 eV ͑corresponding to an energy difference between the HOMO of MDMO-PPV and the LUMO of PCBM of 1.3 eV 16 ͒, P = 0.474, 16 N c = 2.5 ϫ 10 25 m −3 , 16 and G = 2.7ϫ 10 27 m −3 s −1 for the generation rate, corresponding to illumination by a white light halogen lamp ͑spectrum shown in inset of Fig. 3͒ set to 800 W / m 2 , 9 Eq. ͑12͒ predits V oc = 0.8 V at room temperature.…”

“…At room temperature the ideality factor n typically amounts to 1.4 and then further increases to 2.0 at 210 K, in agreement with other observations. 9 Subsequently, the current-voltage characteristic ͑J L -V͒ of an illuminated ͑800 W / m 2 ͒ device at room temperature is shown in Fig. 2, together with the current predicted by Eq.…”

“…͑1͒ to experimental photocurrent data is often improved by including series and shunt resitivities. 9 However, the physical meaning of these quantities is not clear though.…”

Universality of non-Ohmic shunt leakage in thin-film solar cells

“…In terms of the electrical characteristics, shunt currents have been typically considered to be Ohmic in nature. [13][14][15][16][17] In the equivalent circuit picture, this is typically represented by a parallel resistance ͓Fig. 1͑b͔͒.…”

Investigation of PCBM Concentration on the Performance of Small Organic Solar Cell

“…The continuous increase in FF (up to 0.44) by increasing PCBM content (up to 80%), as shown in Figure 6, is a result of continuous lowering in the series resistance of the active layer with increasing PCBM concentration, which is responsible for the electron transfer in the blends. In the BHJ solar cells, the FF relates to the series resistance of the active layer, which reduces as the charge mobility increases [33].…”