Valentin Girleanu

University of Bucharest

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Ioan Stamatin

University of Bucharest

A. Andronie

Politecnico di Milano

Viorel Ionescu

Ovidius University

Nicolae Buzbuchi

Constanta Maritime University

Marina Cuzminschi

Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering

Raluca GHERASIM

Center of Technology and Engineering for Nuclear Projects

Alexei Zubarev

Extreme Light Infrastructure - Nuclear Physics

Cooperative Institutions

University of Bucharest

Constanta Maritime University

Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering

Aix-Marseille Université

Institute of Macromolecular Chemistry

National Institute of Materials Physics

Center of Technology and Engineering for Nuclear Projects

Politecnico di Milano

Extreme Light Infrastructure - Nuclear Physics

National Institute for Laser Plasma and Radiation Physics

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Experimental investigation of cathode back-pressure effect on voltage oscillations in a PEM fuel cell system

Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies IX (2018)

Viorel Ionescu A. Andronie Ioan Stamatin Valentin Girleanu

In this paper we performed an experimental study of a Proton Exchange Membrane Fuel Cell (PEMFC) unit cell having single serpentine type channels for laminar flow of air at cathode and hydrogen at anode using a BEKKTECH BT-552 PEM fuel cell station (USA). Measurements have been collected at two different cathode backpressures of 20 kPa and 50 kPa, for the same anodic backpressure of 400 kPa at an operating temperature of 80°C. Humidified volumetric flow rates of H₂ and air were maintained at 200 sccm and 800 sccm, respectively, with the help of two mass flow controllers. Cell voltage variations of current density loads between 50 mA/cm² and 1000 mA/cm² revealed the air stoichiometry point at which voltage oscillations dropped to negative values, due to air starvation. Another measurements of the PEMFC system voltage, at a constant load of 500 mA/cm² and an air stoichiometry of 3.9 indicated non-uniform oscillations of the cell voltage for a cathodic backpressure of 50 kPa, with maximum peak-to-peak amplitudes ten times bigger than those registered in the case of the test at 20 kPa.

Stoichiometry

10.1117/12.2323345

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Simplified Mathematical Model for Polarization Curve Validation and Experimental Performance Evaluation of a PEM Fuel Cell System

Procedia Manufacturing (2019)

A. Andronie Ioan Stamatin Valentin Girleanu Viorel Ionescu Nicolae Buzbuchi

In this paper we proposed to implement a simple empirical model based on a well-established mathematical correlations of the output voltage for a Proton Exchange Membrane Fuel Cell (PEMFC) system with the current, temperature, partial reactant pressure and membrane conductivity in order to validate two experimental polarization curves, registered at different anode and cathode backpressures and also to evaluate individually different type of cell losses in the form of activation, ohmic and concentration overpotentials. Thermodynamic efficiency of the PEMFC system experimentally tested at different backpressures was also established here.

Ohmic contact

10.1016/j.promfg.2019.02.289

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Citations (12)

Innovative thermo-solar air heater

Energy and Buildings (2017)

Marina Cuzminschi Raluca GHERASIM Valentin Girleanu Alexei Zubarev Ioan Stamatin

Sample (material)

10.1016/j.enbuild.2017.10.082

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Citations (29)

Current - Voltage Variation and Voltage Stability at Constant Load for a PEMFC System with Different Bipolar Plate Flow Fields

Viorel Ionescu Nicolae Buzbuchi A. Andronie Ioan Stamatin Valentin Girleanu

Bipolar plates, as one of the main components of a Proton Exchange Membrane Fuel Cell (PEMFC) system, offer a path for a uniform distribution of reactant gases via flow channels, dissipate heat from reaction sites, prevent leakage of gases and offer the electrical connection between multiple cells in a stack. In this study, a BEKKTECH BT-552 PEMFC test station was used in order to investigate the effect of a three different serpentine-type gas flow fields( M1, M2 and M3) with channel width/channel rib ratios a/w of 1, 1.05 and 1.2 on fuel cell performance at two different system backpressures of 70 kPa and 30 kPa. Cell voltage variations of only 16 mV along a current density step of 0.1 A/cm ² ( at high current densities) have been registered for the fuel unit cell containing flow field M3 with a/w = 1.05 at a backpressure of 70 kPa. The same model presented the highest voltage stability under the test at a constant current load of 0.5 A/cm ² and at a stoichiometric air ratio of 3.2.

Constant current

Stoichiometry

Leakage (economics)

10.1109/atee.2019.8724737

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EXPERIMENTAL STUDY OF A PEMFC SYSTEM WITH DIFFERENT DIMENSIONS OF THE SERPENTINE TYPE CHANNELS FROM BIPOLAR PLATE FLOW FIELDS

Mechanika (2019)

A. Andronie Ioan Stamatin Valentin Girleanu Viorel Ionescu Nicolae Buzbuchi

In this study, a BEKKTECH BT-552 PEMFC test station was used in order to investigate the effect of a three different gas flow fields (with w/a ratios of 1, 1.05 and 1.2) on fuel cell performance at two different system backpressures of 70 kPa ( Test no. 1) and 30 kPa (Test no.2), respectively. The nominal efficiency of the PEM fuel cell was an arbitrary value, located in the domain 0.76 – 0.46 for Test no. 1 and 0.75 – 0.39 for Test no. 2 in the case of the optimized flow field model M3, with w/a ratio of 1.05. DOI: http://dx.doi.org/10.5755/j01.mech.25.1.21907

10.5755/j01.mech.25.1.21907

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Exergy Analysis of a PEM Fuel Cell System with Different Bipolar Plate Flow Fields

Viorel Ionescu Nicolae Buzbuchi A. Andronie Ioan Stamatin Valentin Girleanu

One of the most important part of the Proton Exchange Membrane Fuel Cell(PEMFC) is represented by the graphite-type bipolar plate, witch is also one of the most expensive components of the fuel cell system. In the present study, three different serpentine-type flow field models with folowing geometrical dimensions of channel width/rib width a/w, in mm: 0.9/0.9, 0.78/0.9 and 0.78/0.82, created by milling on graphite bipolar plates have been experimentally tested in a fuel cell. A BEKKTECH BT-552 PEMFC test station was used to investigate the electrical performance of a single fuel cell unit incorporating each of the flow field models at two different backpressures: 70 kPa and 30 kPa. The fuel cell having bipolar plates with flow channel dimensions a/w = 0.78/0.82 presented the highest exergetic efficiency at a backpressure of 70 kPa, with values between 53.3 % and 34.1 % at current densities from 0.05 to 1 A/cm ² and generated electrical power between 0.23 and 3.13 W, and also the the lowest thermodinamic irreversibilities between 0.86 – 5.78 W at the same backpressure and domain for current density and power.

10.1109/atee.2019.8724871

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Citations (2)