The following thesis project comes from the internship experience carried out at Brain Technologies s.r.l for the EVERGRIN project. The aim of the project is to develop a software and hardware product, following a new approach, able to simplify the conversion of a thermal engine vehicle into an electric one. The methodology chosen to develop this project is the Extended V-Cycle, a modified version of the V-Cycle for the automotive sector. The retrofit kit consists of core subsystems such as the Power Box, the Battery Pack and the VMU which is responsible for the e-Powertrain control and e-Powertrain/Vehicle interface. The VMU is a smart device that allows a quick configurability of a new electric car, but which can also be adapted to an existing vehicle, as part of a retrofit activity.