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Conference Object Citation - WoS: 98Citation - Scopus: 101Experimental Investigation of Co Tolerance in High Temperature Pem Fuel Cells(Pergamon-elsevier Science Ltd, 2018) Devrim, Yilser; Albostan, Ayhan; Devrim, HuseyinIn the present work, the effect of operating a high temperature proton exchange membrane fuel cell (HT-PEMFC) with different reactant gases has been investigated throughout performance tests. Also, the effects of temperature on the performance of a HT-PEMFC were analyzed at varying temperatures, ranging from 140 degrees C to 200 degrees C. Increasing the operating temperature of the cell increases the performance of the HT-PEMFC. The optimum operating temperature was determined to be 160 degrees C due to the deformations occurring in the cell components at high working temperatures. To investigate the effects of CO on the performance of HT-PEMFC, the CO concentration ranged from 1 to 5 vol %. The current density at 0.6 V decreases from 0.33 A/cm(2) for H-2 to 0.31 A/cm(2) for H-2 containing 1 vol % CO, to 0.29 A/cm(2) for 3 vol % CO, and 0.25 A/cm(2) for 5 vol % CO, respectively. The experimental results show that the presence of 25 vol % CO2 or N-2 has only a dilution effect and therefore, there is a minor impact on the HT-PEMFC performance. However, the addition of CO to H-2/N-2 or H-2/CO2 mixtures increased the performance loss. After longterm performance test for 500 h, the observed voltage drop at constant current density was obtained as similar to 14.8% for H-2/CO2/CO (75/22/3) mixture. The overall results suggest that the anode side gas mixture with up to 5 vol % CO can be supplied to the HT-PEMFC stack directly from the reformer. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Conference Object Citation - WoS: 85Citation - Scopus: 92Enhancement of Pem Fuel Cell Performance at Higher Temperatures and Lower Humidities by High Performance Membrane Electrode Assembly Based on Nafion/Zeolite Membrane(Pergamon-elsevier Science Ltd, 2015) Devrim, Yilser; Albostan, AyhanThis work reports the preparation of Nafion/zeolite composite membranes with different zeolite loading. The structure of the Nafion/zeolite composite membranes are investigated by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and by thermogravimetric analysis (TGA). The introduction of zeolite particles into the Nafion matrix helps to improve the water uptake, proton conductivity and thermal stability of the nanocomposite membranes compared to the virgin Nafion membrane. The SEM analyses have proved the uniform and homogeneous distribution of zeolite in composite membranes. The composite membranes are tested in a single PEMFC with a 5 cm(2) active area operating at the temperature range of 75-120 degrees C and in humidified under 50% relative humidity (RH) and fully humidified conditions. Single PEMFC tests show that Nafion/zeolite composite membrane is more stable and also performed better than virgin Nafion membrane at low humidity condition. The results indicate the Nafion/zeolite composite membranes could be utilized as the proton exchange membranes for PEMFC. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Review Citation - WoS: 83Citation - Scopus: 92A Review on the Development of the Electrochemical Hydrogen Compressors(Elsevier, 2021) Durmus, Gizem Nur Bulanik; Colpan, C. Ozgur; Devrim, YilserHydrogen should be stored at high pressure and high purity, especially when utilized in fuel cells. Conventionally, mechanical compressors are used for pressurization of hydrogen; however, this technology has disadvantages such as noise and vibration during operation due to their moving parts. Electrochemical hydrogen compressors (ECHC) have emerged as an alternative solution, as these devices can purify and compress hydrogen electrochemically in a single device. This review provides a comprehensive overview of key components and management strategies of the ECHC systems. This review will also provide an overview of different hydrogen compression technologies and provides a comprehensive overview of the latest developments and current issues and future of ECHCs. For this purpose, firstly, the advantages and disadvantages of ECHC compared to mechanical compressors are explained. Then, recent studies on hydrogen purification methods are given. The working principle of ECHC, material development studies and mathematical modeling of ECHCs are also discussed.
