Optimizing battery sizes of plug-in hybrid and extended range electric vehicles for different user types

The results show that the battery size has a significant effect on the TCO. For an average German driver (15,000 km/a), battery capacities of 4 kWh (PHEV) and 6 kWh (EREV) would be cost optimal by 2020. However, these values vary strongly with the driving profile of the user. Moreover, the optimal battery size is also affected by external factors, e.g. electricity and fuel prices or battery production cost. Therefore, car manufacturers should develop a modular design for their batteries, which allows adapting the storage capacity to meet the individual customer requirements instead of “one size fits all”.