Experiments with oxidation circular waves in a quasi-two-dimensional Belousov-Zhabotinsky reaction medium subject to an external de electric field reveal a variety of wave dynamics scenarios involving wave splitting, reversal, annihilation, and complex pattern formation. We also investigate effects of initial concentration of reactants on the wave dynamics and find marked sensitivity related to excitability of the reaction medium. Two different variants of the Oregonator model are shown to have a common dimensionless representation providing conversion relations between corresponding rate coefficients. Modeling of the waves in an electric field is in qualitative agreement with experiments and predicts a rich structure of complex wave dynamics.