NOVELTY - The system (10) has an anode (11), cathode (12), electrolyte (13) and a bipolar plate (14) having two cells connected in series. One of the anode, cathode, electrolyte and the bipolar plate is divided into segments that are electrically insulated from each other. Transfer plates comprise an electrically non-conductive material having two electrical conductive partial pieces and/or connecting area for conducting current from one of the segments to the other segment. An electrically isolating separation element is provided between the segments.    USE - Electro-chemical energy conversion system e.g. battery such as nickel metal hydride battery and lead battery, double layer capacitor and fuel cell e.g. proton exchange membrane fuel cell, for a hybrid vehicle.    ADVANTAGE - The anode, cathode, electrolyte or the bipolar plate is divided into the segments that are electrically insulated from each other, and the transfer plates are integrated into the system, so that the current flow of the electro-chemical energy conversion system from a fuel cell stack and redox flow batteries are homogenized, and the current flowing into electrodes and electrolyte against a preferred direction during the current discharge is prevented, thus avoiding damages of the electro-chemical energy conversion system in a favorable manner. The homogeneous current distribution in the anode, cathode, electrolyte and the bipolar plate from the electrodes of the fuel cell stack guides to an even temperature of the electrodes with reduced temperature maxima, so that temperature-dependent aging processes are slowed down and the danger by local excesses of temperature limit values is decreased or prevented. The homogeneous current density distribution provides an even fuel utilization in the fuel cell, so that risk of a local fuel cell lacking causing an accelerated aging process is avoided while minimizing temperature gradients within the electro-chemical energy conversion system during a stationary operation or changing power output of the electro-chemical energy conversion system. The temperature gradients have a reduced influence on the service life of the electro-chemical energy conversion system.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of a fuel cell stack.'(Drawing includes non-English language text)'    Electrochemical energy conversion system (10)    Anode (11)    Cathode (12)    Electrolyte (13)    Bipolar plate (14)