The results of investigations into the main characteristics of the traction system of the electric motorcar (EM) with application of super capacitors (SC) to the EM starting and acceleration regimes are given. Dynamics of the consumed power at the EM starting and acceleration up to the specified speed, taking into account its mass, acceleration time and aerodynamic characteristics, is investigated. The authors have developed the microcontroller device ensuring the decrease in the peak load on the accumulator battery (AB) at the moment of the EM starting and acceleration, as well as the automatic redistribution of the electric motor electrical supply between the SC and AB. The results are: (1) It is shown that the electric motorcar peak power at the acceleration stage is inversely related to the acceleration time and it is in direct proportion to its mass all other factors being equal. (2) The AB discharge regime practically defines the electric motorcar endurance, it depends on the accumulator battery type and the current load (the electric motor power). It is determined that with increase in the current load by a factor of three (from 1,4 A to 4,2 A) the AB discharge cycle time reduces significantly and the run time decreases, respectively. (3) It is determined that the SC charging time increases proportionally with the capacity value and the discharge cycle time depends both on the capacity value and on the current load. (4) It is shown that the SC use smoothes out the AB current in the system of the traction electric drive, this, in its turn, increases the run time between charging. It is determined that if the SC power consumption is less than 15-25% in reference to the AB it is practically impossible to realize the advantages of their united use. With increasing the power stored by the SC relative to the AB power from 10% to 24% the relative run time increases from 10% to 20%. (5) The microcontroller system for regulation of the AB and SC operating conditions in the electric motorcar traction system is offered, it provides the optimal and prompt control over the electric motor power supply.