A method, device, and system for managing a fleet of vehicles is disclosed. The method includes providing a telematics device for an electric vehicle of the fleet of vehicles, the telematics device being capable of obtaining data from the electric vehicle; using the telematics device to identify the electric vehicle based on the data obtained from the electric vehicle; providing a data definition set for the electric vehicle to the telematics device; and using the telematics device and the data definition set to determine whether the electric vehicle is in a vehicle mode based on the data obtained from the electric vehicle and the data definition set. The vehicle mode of the electric vehicle can be at least one of a charging mode, a driving mode, and a parked mode.