Integrated organic photovoltaic modules with a scalable voltage output

Efficient organic photovoltaic modules and cells have been fabricated based on a blend of poly(3-hexylthiophene) (P3HT) and a soluble C-70 derivative, [6,6]-phenyl C-71 butyric acid methyl ester (PCBM-70). Power conversion efficiency of P3HT/PCBM-70 cells is estimated at 4.1% for the AM1.5 G condition from the spectra of external quantum efficiency. Integrated photovoltaic modules, in which N- individual P3HT/PCBM-70 cells (N=1-4) are connected in series, exhibit a short-circuit current I-SC of 1.4 +/- 0.1 mA and an open-circuit voltage V-OC of Nx0.621 V with a maximum V-OC of 2.48 V for N=4 under simulated solar illumination (AM1.5 G, 85 mW/cm(2)). (c) 2006 American Institute of Physics.