This paper presents supercapacitors and battery association methodology for ECCE Hybrid vehicle. ECCE is an experimental Hybrid Vehicle developed at L2ES Laboratory in collaboration with the Research Center in Electrical Engineering and Electronics in Belfort (CREEBEL) and other French partners. This test bench has currently lead-acid batteries with a rated voltage of 540 V, two motors each one coupled with one alternator. The alternators are feeding a DC-bus by rectifers. The main objective of this paper is to study the management of the energy provides by two supercapacitor packs. Each supercapacitors module is made of 108 cells with a maximum voltage of 270 V. This experimental test bench is carried out for studies and innovating tests for the Hybrid Vehicle applications. The multi boost and multi full bridge converter topologies are studied to define the best topology for the embarked power management. The authors propose a good power management strategy by using the multi boost and the multi full bridge converter topologies. The experimental and simulation results of the two converter topologies are presented.