Battery electric vehicles (BEVs) are considered as a critical pathway towards achieving energy independence and meeting greenhouse and criteria pollutant gas reduction goals in the current and future transportation sector. Emerging connected and automated vehicle (CAV) technologies further open the door for developing innovative applications and systems to leverage vehicle efficiency and substantially transform transportation systems. Therefore, we present a simulation study of various BEV types and compare the performance when driving on real-road drive cycles to highly optimized eco-driving cycles that are representative of trajectory modifications using advanced CAV technologies. The results demonstrate eco-driving has a high potential to reduce energy consumption for all types of BEVs considered. The investigated BEVs include a compact vehicle, a transit city bus, and a Class 7 delivery truck. The impact of eco-driving on conventional vehicles was also compared to comparable BEVs. The observations show eco-driving provides a larger reduction in the conventional vehicle’s braking energy loss compared to the comparable BEVs. Compared to BEVs, eco-driving provides conventional vehicles with greater reductions in the engine mechanical energy output and complex fuel savings. As part of the study, a comprehensive EV powertrain model was developed to account for key EV components and powertrain configurations.