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AuthorMarcu, Alinadc.contributor.author
Date of accession2016-03-15T10:41:35Zdc.date.accessioned
Available in OPARU since2016-03-15T10:41:35Zdc.date.available
Year of creation2013dc.date.created
AbstractThis research was designed to meet Daimler systematic efforts to address future electromobility demands. The work focuses on developing potential cathode catalysts and tests procedures to be employed in prototype fuel cells. In order to achieve commercial cost-competitive polymer electrolyte membrane fuel cells (PEM FC), the following major challenges have to be addressed: i) The catalytic mass activity of the cathode catalysts has to be at least 0.44 A/mg Pt representing an increased factor of four compared to standard carbon supported platinum Pt/C catalysts, ii) maintenance of an enhanced activity over the catalysts life time of about 6000 h, and iii) low cost of the cathode catalysts with less than 5 $/kW. To increase the performance and reduce the costs, Pt atoms of standard nanoparticle catalysts were partially replaced with non-noble metal Cu to result in PtCux-skeleton and core-shell. The durability of the catalysts prepared in-house was systematically evaluated and clarified for various fuel cell voltage cycles. A liquid electrolyte SU/SD test procedure is proposed and developed in this work, based on automotive stack voltage responses. The ex-situ test procedure has the advantage of being faster and less costly than in-situ tests. In addition, it allows distinguishing between quantifying the failure modes contributing to degradation: i) Pt dissolution, ii) Pt agglomeration and iii) carbon corrosion. Accelerated degradation test procedures for the Pt-based cathode catalysts, simulating the drive cycles, are also developed and discussed in this research. Square wave cycles (SWC) and triangular wave cycles (TWC) were systematically evaluated and compared. The knowledge achieved in this research provides technology insights to potential application in the electromobility development in Daimler.dc.description.abstract
Languageendc.language.iso
PublisherUniversität Ulmdc.publisher
LicenseStandarddc.rights
Link to license texthttps://oparu.uni-ulm.de/xmlui/license_v3dc.rights.uri
KeywordCarbon corrosiondc.subject
KeywordElectrocatalystsdc.subject
KeywordElectrochemical testing protocolsdc.subject
KeywordPotential profiledc.subject
KeywordPt dissolutiondc.subject
KeywordVoltammetric dealloyingdc.subject
Dewey Decimal GroupDDC 540 / Chemistry & allied sciencesdc.subject.ddc
LCSHAlloysdc.subject.lcsh
LCSHFuel cellsdc.subject.lcsh
TitlePreparation, characterization and degradation investigations of cathode catalysts for automotive PEM fuel cells systemsdc.title
Resource typeDissertationdc.type
DOIhttp://dx.doi.org/10.18725/OPARU-3440dc.identifier.doi
PPN1659092795dc.identifier.ppn
URNhttp://nbn-resolving.de/urn:nbn:de:bsz:289-vts-91991dc.identifier.urn
GNDPolymer-Elektrolytmembran-Brennstoffzelledc.subject.gnd
FacultyMedizinische Fakultätuulm.affiliationGeneral
Date of activation2014-08-29T14:28:12Zuulm.freischaltungVTS
Peer reviewneinuulm.peerReview
Shelfmark print versionW: W-H 13.764uulm.shelfmark
DCMI TypeTextuulm.typeDCMI
VTS-ID9199uulm.vtsID
CategoryPublikationenuulm.category
University Bibliographyjauulm.unibibliographie


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