Application of an ionic liquid-based electrolyte to a 100 mm×100 mm sized dye-sensitized solar cell

In this study, an ionic liquid-based electrolyte was applied to a 100 mm×100 mm sized dye-sensitized solar cell (DSC). For the purpose of fabricating a large sized DSC, influence of electrode distance, TiO2 nano-particle size, thickness of TiO2 nano-porous layer were investigated in ionic liquid; 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide (EMIm–TFSA) electrolyte system. It was cleared that short-circuit current (Jsc) was remarkably influenced by those factors compared with conventional volatile electrolyte system. At optimized condition, energy conversion efficiency of 4.5% was obtained using 9 mm×5 mm small sized cell. Energy conversion efficiency of a large sized cell was 2.7% on ionic liquid system, and 2.4% on ion–gel system based on the active area (2.3 and 2.0%, respectively, based on the total area). Cell performance was drastically improved by decreasing of internal cell resistance, mainly attributed to conductivity of a transparent conductive oxide (TCO) substrate.