From its first debut, the Tesla Model S powertrain has undergone numerous revisions that have improved its longevity, efficiency and power. The Model S can recoup the energy required to produce it in less than 10,000 miles. More than 60 kW of regenerative braking power is available from the drivetrain, which significantly lowers brake wear and energy consumption. Since there is an electronic power distribution between the two induction motors, there is no mechanical linkage between the front and back axles. As a matter of fact, accurate powertrain modeling and validation are paramount for critical design and control decisions of high performance electric vehicle. Described in this paper is a methodology for the design and description of Tesla Model S powertrain components. Justification of real-world vehicle system focusing on battery management system, CAN bus and regenerative braking is also provided.