The present research is focused on developing solutions for increasing the lifetime of the batteries used on diesel locomotive. In order to increase the lifetime of the batteries and to reduce the fuel consumption and the pollutants, an intelligent starting system of the diesel locomotive is proposed. The starting system is composed of supercapacitors, batteries and adequate control system used for controlling the power flow from the storage devices to the internal combustion engine in the starting process. The implementation is described, modeled and simulated and the results of the simulations are compared with the experimental ones.