A comparative study of different bipolar current injection methods viz. Adjacent method, Cross method and Opposite method used in Electrical Impedance Tomography(EIT) is reported in this paper. Different electrode configurations are considered for current injection and voltage measurement to identify the one which yields better signal strength. Sensitivity of different current injection methods to inhomogeneity at different locations is examined. The effect of conductivity contrast on boundary voltages is studied by varying the conductivity of the inhomogeneity from 0.01mS/cm to 9.1mS/cm. Ill-posedness of the inverse problem is analyzed in terms of condition number for the aforementioned methods. Reconstruction of two closely placed inhomogeneities is done using Levenberg Marquardt method for different current injection methods to compare the resolution and corresponding error voltage is determined. Experiments are conducted using agar phantoms to validate some of the results obtained from the simulations. Based on the simulation studies and experimental validations, cross method is found to be the optimal current injection method to attain better data acquisition and image reconstruction.