The lifetime and aging of the high voltage battery is one of the major discussion points for the end-customer to decide between buying a car with an electric powertrain or still using a conventional powertrain. Therefore, the provision of adequate vehicles to the end-customer, the aging of the high voltage battery become an important topic for the complete vehicle development. In addition, also legal regulations (e.g. EU7) will preset minimum requirements for the warranty of the high voltage battery. These circumstances define the lifetime / aging of the HV battery to be a complete vehicle development target, which needs to be developed. The paper will present a method for the development process of a lifetime target from complete vehicle perspective. The method is based on the generation of a representative monthly power profile and temperature profile. Depending on a monthly user routine, ambient temperature profile and charging behavior, the vehicle specific battery power profile will be generated using energy flow simulation. In addition, the simulation of the HV battery SoC and temperature is included, too. Second, using a generic battery cell aging model, the impact on the state of health will be estimated using the power and temperature profile for the lifetime of the battery. The aging behavior over lifetime of the HV battery can be estimated. Using the tools, several sensitivity studies have been performed (e.g. impact on charging behavior, ambient temperature, vehicle operating strategy) to understand the main impacts on battery aging. The simulation tool as well as the results of the sensitivity analysis will be presented in the paper.