The increased installation of additional consumers such as infotainment systems leads to an increase of power requirements during driving and even when the vehicle is at a standstill. Therefore, energy management is necessary as soon as the required power could not be produced by the generator at that time. Knowledge of the battery status is essential for this. Drivers are already used to service displays for other vehicle components: brakes, oil pressure and cooling water are all detected by sensors, and a visit to the garage is requested when necessary. Up to now, there have not been any such predictions for the battery. A precise prediction of battery behavior and failure is extremely complicated and difficult to put into practice on account of the multitude of parameters influencing the battery. Investigations by automobile associations and manufacturers show that the main reason for car breakdown is the power supply, which in turn is closely related to the battery. Even if the battery only represents the actual cause of vehicle failure in a minimum number of cases, drivers still wish they had a reliable prediction of when a service is due and/or the battery needs replacment in order to avoid break-downs. Accurate knowledge of the battery state is required since this information forms the fundamental basis of every energy management functionality. The Intelligent Battery Sensor (IBS), jointly developed by Hella, Autokabel and BMW, is a mechatronic device integrated into the standard battery terminal. The IBS is able to record battery voltage, current and temperature very precisely over wide operating ranges. Since the Intelligent Battery Sensor comprises all of the necessary electronics and mechanical parts for integration in the battery clip, this design concept incorporates several additional advantages for vehicle operation, production and service.