Search results for "Fuel Cell"
showing 10 items of 260 documents
Nanoporous alumina membranes filled with solid acid for thin film fuel cells at intermediate temperatures
2004
Thin film fuel cells have been fabricated by impregnation of inorganic porous membranes with inorganic proton conductor. Anodic alumina membranes (50 μm thick and pore diameter of 200 nm), filled with CsHSO4 salt have been used as protonic conductor in a hydrogen-oxygen fuel cell working between 423 and 443 K in dry atmosphere. Polarization curves at 433 K showing ohmic control with open circuit values near 0.8 V and short circuit current around 8 mA cm−2 have been obtained. Possible causes of degradation as well as alternative routes to overcome some of the problems encountered with this approach will be reported. Keywords: Solid acid, Anodic alumina membranes, Pore filling, Thin film fuel…
Performance of Sulfonated Poly(Vinyl Alcohol)/Graphene Oxide Polyelectrolytes for Direct Methanol Fuel Cells
2020
The use of nanotechnology along with the consideration of a functionalization and stabilization approach to poly(vinyl alcohol) (PVA) is considered useful for the preparation of cost-effective polyelectrolyte membranes. A set of nanocomposite and crosslinked membranes based on PVA/sulfosuccinic acid (SSA)/graphene oxide (GO) are prepared and analyzed as polyelectrolytes in direct methanol fuel cells (DMFCs). The crosslinking and sulfonation by the use of SSA enhances the stability and increase the proton-conducting sites in the PVA structure. The presence of GO augments the stability, remarkably decreases the methanol crossover, and enhances power density curves. An optimum value for proton…
Crosslinked chitosan/poly(vinyl alcohol)-based polyelectrolytes for proton exchange membranes
2019
[EN] The preparation polyelectrolytes based on crosslinked poly(vinyl alcohol) (PVA) and chitosan (CS) was considered as a feasible alternative to develop highly functionalised, cost-effective and eco-friendly membranes for proton exchange fuel cell technologies. CS/PVA-based membranes were combined with sulfosuccinic acid (SSA) as crosslinking and sulfonating agent, and glycerol (GL) to promote flexibility and favour their manageability. The chemical structure, the thermo-oxidative behaviour, the ethanol uptake, the electric, the proton conductivity, and the performance in direct ethanol fuel cell (DEFC) were assessed. In general, all the CS/PVA-based polyelectrolytes showed a synergetic i…
Functionalised poly (vinyl alcohol)/graphene oxide as polymer composite electrolyte membranes
2019
[EN] Crosslinked poly(vinyl alcohol) (PVA) based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells (DEFC). The membranes were functionalised by means of the addition of graphene oxide (GO) and sulfonated graphene oxide (SGO) and crosslinked with sulfosuccinic acid (SSA). The chemical structure was corroborated and suitable thermal properties were found. Although the addition of GO and SGO slightly decreased the proton conductivity of the membranes, a significant reduction of the ethanol solution swelling and crossover was encountered, more relevant for those functionalised with SGO. In general, the composite membranes were stable under …
Parameters identification of the complex impedance model of the PEM fuel cell using Matlab/Simulink
2017
In this work, we present a new technical method for identifying the complex impedance model parameters of a Proton Exchange Membrane (pEM) Fuel Cell for on-board diagnosis in real time. The study of the PEM Fuel Cell modelling is important in order to understand the physical phenomena that occurring in this green renewable energy source. A diagnosis method is presented by analyzing the behavior of the complex impedance. For this, we present the identification method of the various complex impedance parameters; this identification is based on mathematical methods using the least squares method and the interpolation analysis method. The results are obtained using Matlab/Simulink tools and all…
X-ray Spectroscopy of (Ba,Sr,La)(Fe,Zn,Y)O3-δIdentifies Structural and Electronic Features Favoring Proton Uptake
2020
Mixed protonic–electronic conducting oxides are key functional materials for protonic ceramic fuel cells. Here, (Ba,Sr,La)(Fe,Zn,Y)O3−δ perovskites are comprehensively investigated by X-ray spectroscopy (in oxidized and reduced states). Extended X-ray absorption fine structure shows that Zn,Y doping strongly increases the tendency for Fe–O–Fe buckling. X-ray absorption near-edge spectroscopy at the Fe K-edge and X-ray Raman scattering at the O K edge demonstrate that both iron and oxygen states are involved when the samples are oxidized, and for the Zn,Y doped materials, the hole transfer from iron to oxygen is less pronounced. This can be correlated with the observation that these material…
Y:BaZrO 3 Perovskite Compounds II: Designing Protonic Conduction by using MD Models
2011
The proton dynamics in Y-doped BaZrO(3) derivatives, in particular the different dopant environments within a Pm3m cubic framework, were studied by using classical molecular dynamics (MD) calculations. Single- and double substitution of zirconium by yttrium atoms was considered. The presence of yttrium induced variations in the surrounding oxygen sites, according to their local geometrical arrangements. The differences among such distinct oxygen sites became evident when protons interacted with them and upon changes in the temperature. So, different proton transfer pathways, which had different energy barriers, characterized the topologically different oxygen sites. The experimental proton-…
Flash microwave synthesis and sintering of nanosized La0.75Sr0.25Cr0.93Ru0.07o3–δ for fuel cell application.
2009
International audience; Perovskite-oxide nanocrystals of La0.75Sr0.25Cr0.93Ru0.07O3–δ with a mean size around 10 nm were prepared by microwave flash synthesis. This reaction was performed in alcoholic solution using metallic salts, sodium ethoxide and microwave autoclave. The obtained powder was characterised after purification by energy dispersive X-ray analysis (EDX), X-ray powder diffraction (XRD), BET adsorption technique, photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM). The results show that integrated perovskite-type phase and uniform particle size were obtained in the microwave treated samples. At last the synthesised powder was directly used in a sin…
Development of anode supported Single Chamber Solid Oxide Fuel Cells running in air/methane mixture
2013
International audience; Single Chamber Solid Oxide Fuel Cells (SCFC) show a growing interest and are the concern of more and more papers. In such device, anode and cathode are ex-posed to a gas mixture of fuel (hydrocarbon) and oxidant (air) so that no more sealing with electrolyte is necessary. Their operating principle is based on the different catalytic activities of anode and cathode: Ideally, the anode has to be active for the oxidation of fuel while the cathode should present only a strong electro-activity for oxygen reduction. In this paper, we present the development of an anode supported SCFC device running in air/methane mixture characterized by their volume ratio, Rmix = CH4/O2.
PEM FC Single Cell Based on a 3-D Printed Plastic Housing and Experimental Validation with the Mathematical Model
2018
Abstract This paper presents the design, modelling, and testing of a PEM single fuel cell based on the use of 3D printing. The design of the housings was made of SolidWorks, while MATLAB/SIMULINK were used to model performance. The fabricated cell performed satisfactorily with no leaks of gas, showing that the 3D printing method can be used in the additive manufacturing of fuel cells thus leading to significant cost savings.