Development of a near-dead-ended fuel cell stack operation in an automotive drive system

During the past decade several important development steps, such as the 700 bar hydrogen storage or the freeze start capability, have brought fuel cell electric vehicles close to market introduction. Further drive system cost reduction by e.g. simplification of the fuel cell system architecture are intended for future fuel cell vehicle generations. Removing the anode recirculation loop and operating the fuel cell stack in the so-called near-dead-ended mode is one promising concept. Key experiments focussed on the fuel cell stack's anode side under vehicular load conditions and temperature levels have been performed successfully while maintaining fuel consumption constraints. The impact of cathode operating conditions on the liquid water accumulation and hydrogen concentration on the anode side has been investigated by simulation in order to optimize the operation of this lean anode concept.