hybrid system of a fuel cell (FC) and batteries connected to a non-linear load is presented. FC do not work properly under transient conditions. The sharp changes in the load power demand cause sever electrochemical and thermal non-uniformities in FC. These non-uniformities increase the degradation rate of FC and reduce its expected life span. To mitigate these detrimental effects, a battery bank is used along with FC. This paper deals with the state space modeling of the hybrid system, and the control of the DC Bus voltage by the Interconnection and Damping Assignment Passivity-Based Control (IDA-PBC). IDA-PBC is a useful technique to control systems assigning a desired Port-Controlled Hamiltonian (PCH) structure to the closed-loop. The global stability proof and simulation results are presented.