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Munchen, Germany

Heinzl C.,Ludwig Maximilians University of Munich | Ossiander T.,Elcomax GmbH | Gleich S.,Max Planck Institute Fur Eisenforschung | Scheu C.,Max Planck Institute Fur Eisenforschung
Journal of Membrane Science | Year: 2015

The incorporation of silica nanostructures in polymer membranes is beneficial for the chemical, mechanical and the life time stability of high temperature proton exchange membrane fuel cells. Since the properties are closely related to the morphology and chemical composition of the constituents, their detailed investigation is of importance. In this paper transmission electron microscopy is utilized to study cross-linked silica nanoparticles in phosphoric acid doped polybenzimidazole membranes, which are formed by an in-situ sol-gel reaction using varying reaction parameters. The results show that by an additional heating step before membrane casting, several hundred nanometer large, ellipsoidal silica particles are formed in the membrane. Small, elongated nanoparticles with sizes in the range of about 20. nm are present in all samples independent of the heat treatment. In-depth energy dispersive X-ray spectroscopy and electron energy loss spectroscopy analysis proved the homogeneous distribution and composition of the amorphous silica nanoparticles and revealed that no enrichment occurs at the interface between nanoparticles and polymer. The ex-situ membrane investigations reveal a higher chemical and mechanical stability for membranes containing the large, ellipsoidal particles. However, the membrane with only smaller silica nanoparticles shows a better degradation behavior than the membrane with large particles. © 2015 Elsevier B.V.

Schenk A.,University of Graz | Grimmer C.,University of Graz | Perchthaler M.,University of Graz | Perchthaler M.,Elcomax GmbH | And 7 more authors.
Journal of Power Sources | Year: 2014

Platinum cobalt catalysts (Pt-Co) have attracted much interest as cathode catalysts for proton exchange membrane fuel cells (PEMFCs) due to their high activity toward oxygen reduction reaction (ORR). Many of the reported catalysts show outstanding performance in ex-situ experiments. However, the laborious synthesis protocols of these Pt-Co catalysts disable an efficient and economic production of membrane electrode assemblies (MEAs). We present an economic, flexible and continuous Pt-M/C catalyst preparation method as part of a large scale membrane electrode assembly manufacturing. In comparison, the as-prepared Pt-Co/C based high temperature (HT)-PEM MEA showed an equal performance to a commercially available HT-PEM MEA during 600 h of operation under constant load, although the commercial one had a significantly higher Pt loading at the cathode. © 2014 Elsevier B.V. All rights reserved.

The present invention relates to a polymer electrolyte membrane for fuel cells, comprising a polymer matrix of at least one basic polymer and one or more doping agents, wherein particles containing ionogenic groups and having a mean particle diameter in the nanometer range are embedded in the polymer matrix and the particles containing ionogenic groups are distributed homogeneously in the polymer matrix in a concentration of less than 50% relative to the weight of the polymer matrix, as well as to the production and use of same, especially in high-temperature fuel cells.

Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: NMP.2012.1.1-1 | Award Amount: 3.07M | Year: 2013

The main general goal of DECORE is to achieve the fundamental knowledge needed for the development of a fuel cell (FC) electrode, which can operate efficiently (both in terms of activity and selectivity) as the anode of a direct ethanol (EOH) FC (DEFC) in the temperature range between 150-200 C (intermediate-T). Such a technology is still lacking in the market. The choice for EOH as an alternative energy source is well founded on the abundance of bioethanol, and on the relatively simpler storage and use with respect to other energy carriers. The intermediate-T is required for an efficient and selective total conversion of EOH to CO2, so exploiting the maximum number of electrons in the DEFC. DECORE will explore the use of fully innovative supports (based on titanium oxycarbide, TiOxCy) and nano-catalysts (based on group 6 metal carbides, MCx, M=Mo,W), which have never been tested in literature as anodes for DEFCs. The new support is expected to be more durable than standard carbon supports at the targeted temperature. The innovative nano-catalysts would be noble-metal free, so reducing Europes reliance on imported precious metals. To tailor the needed materials, the active role of the support and nano-catalyst will be studied at atomic level. Demonstrating an activity of such nano-catalyst/support assembly at intermediate-T would open a novel route where DEFCs with strongly reduced production costs would have an impact on a fast industrialisation. The power range for the envisioned application is of the order of hundreds of Watts, i.e. the so called distributed generation, having an impact for devices such as weather stations, medical devices, signal units, auxiliary power units, gas sensors and security cameras. By the end of the project, a bench-top single DEFC operating at intermediate-T will be built and tested.

Elcomax GmbH and Rhein Chemie Rheinau GmbH | Date: 2010-12-14

The invention relates to the use of a material imparting proton conductivity in the production of fuel cells, said material consisting of monomer units and having an irregular shape.

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