<p>This study investigates the coalescence dynamics between two droplets of different sizes in an electric field using an open-source solver and the volume of fluid (VOF) method. We explore how varying the electric field strength and the permittivity and conductivity ratios of the fluids affect coalescence. Key electrical parameters are identified that mark the transition from partial to complete coalescence while keeping properties like the Ohnesorge number, Atwood number, and Bond number constant. The electric field enhances the downward fluid transfer from the mother droplet to the father droplet, facilitating coalescence. However, at intermediate electric field strengths, the upward electrical force on the droplet surface can dominate, leading to secondary droplet formation. Optimal electric field strength achieves complete coalescence without smaller, challenging-to-separate secondary droplets. This study emphasizes the critical electric field strength at which partial coalescence ends.</p>