The Tesla Cybercab is set to have a sub-50-kWh battery pack.Despite its smaller battery size, the Cybercab is expected to have a driving range of close to 300 miles.The Cybercab's efficiency is estimated to be 6 miles per kilowatt-hour, surpassing other efficient EVs.The car's design, including the teardrop shape and lightweight materials, contributes to its high efficiency.