Optimizations of large area quasi-solid-state dye-sensitized solar cells

In this paper, we address optimizations of dye sensitized solar cells (DSSCs) through the combination of important issues like semi-transparency, quasi-solid-state constructions and low-cost realization of serially connected modules. DSSCs with a transparency of 50% in the visible region, moderate efficiency similar to 1%, and long lifetime allow solar cells application in building elements like windows, facades and semi-transparent roofs. The use in DSSCs of gel polymer electrolytes prepared by liquid electrolyte incorporation into a polymer matrix such as poly-methyl-methacrylate presents encouraging results. A short circuit current (I-sc) of 4.45 mA cm(-2) with an open circuit voltage (V-oc) of 0.5 V were recorded in standard solar cells sensitized by cis-bis(thiocyano) ruthenium(II)-bis-2, 2'-bipyridine-4, 4'-dicarboxylate. Up-scaling tests demonstrate the easy realization of a 625 cm(2) module connected in series which allows power extraction up to similar to 100 mW with an I-sc of 25.1 mA and a V-oc of 10.65V under AM 1.5, 100 mW cm(-2) standard conditions. Losses are minimized by using a low-current/high-voltage coupling scheme. (c) 2006 Elsevier B.V. All rights reserved.