The paper discusses a simulation platform developed in Matlab/Simulink suitable for the modelling and analysis of combined energy sources and components considered for electric vehicle power trains. While there are a number of similar simulation tools in literature, the simulation model elements each have suitable resolution to model detailed dynamic operation, an important consideration when assessing the specification requirements for the interconnection of multiple electrical components and their associated interface power electronics. Models are presented for a number of vehicle power-train components that can be interconnected to investigate alternative energy sources and power-train components proposed for electric vehicles, the combination of which is undertaken to exploit their various attributes. In particular, the paper considers the combination of an energy dense ZEBRA battery and power dense supercapacitor. The energy dense source is specified and operated to fulfil the requirements for vehicle range, while the power dense source provides the peak power for acceleration or regenerative braking and to help improve the regulation of the vehicle dc supply.