192 Effect of Internal Resistance on Current-Voltage Characteristics and Performance Parameters of Dye Sensitized Solar Cells Studied by Building Circuits

Internal resistances are harmful to device performance. Due to the difficulty in fabrication of typical devices with varied internal resistances, detailed effect of internal resistance in dye sensitized solar cells has not been observed in experiments. Such problem is then solved by building model cells using a typical dye sensitized solar cell and a resistance box. The resistance box acts as the internal resistance of the model cell. By varying output of the resistance box, the effect of internal resistance in the model cell is studied. It is observed that, there exists a relationship of competition between heterojunction and resistance in determination of current-voltage characteristics of the cells. The so-called “characteristic resistance” plays an important role in determination of fill factor of the cell. Based on the observations, relationships between photo-to-electric energy conversion efficiency and resistances, performance evaluating parameters like illumination intensity and irradiated area of the solar cells are discussed.