This paper presents a study related to a more efficient energy management between battery and Supercapacitors (SC) for Hybrid Electric Vehicle (HEV) applications. This idea is due to the present trend in the field, knowing that the major drawback of the HEV is the autonomy problem. Thus, using supercapacitors and battery with a good energy management strategy improves the HEV performances. The originality of this paper is focused on DC-bus voltage and currents control strategy based on polynomial controller. This strategy is implemented in PIC18F4431 microcontroller for DC/DC converters control. For reasons of cost and available components (no optimized) such as the battery and power semiconductors (IGBT), the experimental test bench is designed in reduced scale. Through some simulations and experimental results the authors present an improved energy management strategy for HEV.