Mixed halide lead perovskites offer a useful strategy for continuous tuning of the semiconductor bandgap. For example, by varying the halide composition of methylammonium lead iodide/bromide (CH₃NH₃PbBr_xI_3-x (x=0 to 3)) it is possible to tune the bandgap between 1.55 eV and 2.43 eV. The excited state characterization using emission and transient absorption spectroscopy has allowed us to probe the photoinduced processes. Of particular interest are mixed halide lead perovskites (e.g.,CH₃NH₃PbI_3-xBr_x) which undergo phase segregation to create Iodine-rich and Bromide- rich regions when subjected to visible irradiation. We have now investigated the effect of such phase segregation effect on the photovoltaic properties of mixed halide perovskites. The mixed halide solar cells upon exposure to white light exhibit a decrease in the photocurrent and photovoltage as the films undergo phase segregation. The iodide treatment helps to minimize these segregation effects and restore the photovoltage upon storing in the dark. The photovoltaic performance of perovskite solar cells with varying degree of halide treatment will be discussed.