Mounir Nasri

Range extender vehicle concept based on high temperature Polymer Electrolyte Membrane Fuel Cell

Battery electric vehicles that would be suitable for urban traffic as well as for longer distances will be equipped with a range extender (REX). In this range extender vehicle concept, the powertrain is driven mainly by the high performance li-ion battery added by a HT-PEFC (Polymer Electrolyte Membrane Fuel Cell). The on-board fuel cell range extender serves as an additional energy source, which charges the high performance battery during the trip especially in a long distance trip. On the basis of existing system models, such as fuel cell and battery, a complete vehicle model is been developed with the help of the AlternativeVehicles library [1], especially the thermal model has been extended and parameterized. For the thermal coupling between the high-temperature fuel cell and the hydrogen storage, a high temperature cooling circuit is modeled. The battery temperature control is represented in the model by means of a low-temperature cooling circuit. Considered the challenges that are now placed on modern cars, several scenarios such as cold start and warm-up phase are been created. For these scenarios, suitable operating strategies can be developed and integrated into the overall vehicle model. Based on various driving cycles, the thermal and electrical behavior of the overall system is investigated.

Thermal management of fuel cell-driven vehicles using HT-PEM and hydrogen storage

A battery electric vehicle equipped with a range extender is a suitable solution for both urban and long-distance traffic. Compared with the internal combustion engine-powered range extender the fuel cell range extender is a zero emission solution and has been investigated for many years. In this work a system for hydrogen storage for the heating and cooling of a high temperature polymer membrane fuel cell range extender itself using a metal-hydride storage tank [1] is investigated. In order to survey the suitability of this system for electric vehicles, an overall vehicle simulation model using the AlternativeVehicles library [2] is developed. Taking into consideration the challenges that are now placed on modern cars, several scenarios such as cold start and normal operation are created. For these scenarios suitable operating strategies are developed and integrated into the overall vehicle model. Based on various driving cycles the thermal and electrical behavior of the thermally coupled high temperature polymer membrane fuel cell and the metal-hydride storage tank is investigated.

Thermal management concept for next generation vehicles

In this paper, a thermal management concept for future intercity and long-distance vehicles is described in which the waste heat from a fuel cell system was being used for heating the cabin inlet air. To this end, various waste heat utilization concepts are created with different location of heat-exchanges and PTC-heaters and then modeled in the simulation environment Modelica/Dymola. From the obtained simulation results, a suitable waste heat utilization concept is examined in the entire vehicle.

Waste heat recovery for fuel cell electric vehicle with thermochemical energy storage

In this paper, different waste heat recovery concepts for a high temperature fuel cell range extender vehicle developed by the DLR Institute of Vehicle Concepts will be presented. These concepts use thermochemical heat storages to recover thermal energy from the powertrain waste heat and to re-use it for heating purpose before or during the drive. The focus will be on metal hydride storages, which have a higher specific energy density than the phase change energy storages and will thus be more advantageous for vehicle application. In order to investigate the developed waste heat recovery concepts in the entire vehicle, appropriate simulation models will be created in the simulation environment Modelica/Dymola, then integrated into an overall vehicle simulation model. It is found that the integration of the thermochemical heat storages into the fuel cell thermal management system leads to increase the range by up to 17 %.