% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@PHDTHESIS{Borgardt:891876,
author = {Borgardt, Elena},
title = {{M}echanische {E}igenschaften von katalysatorbeschichteten
{M}embranen für die {P}olymer-{E}lektrolyt-{M}embran
{E}lektrolyse},
journal = {Anatomical science international},
volume = {533},
issn = {-},
school = {RWTH Aachen},
type = {Dissertation},
address = {Jülich},
publisher = {Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag},
reportid = {FZJ-2021-01789},
isbn = {978-3-95806-533-8},
series = {Schriften des Forschungszentrums Jülich. Reihe Energie
$\&$ Umwelt / Energy $\&$ Environment},
pages = {viii, 181 S.},
year = {2021},
note = {RWTH Aachen, Diss., 2020},
abstract = {With the aim of substituting fossil fuels, the expansion of
renewable electricity generation in Germany hasbeen strongly
promoted in recent years. Due to weather conditions,
electricity from wind and solar poweris subject to high
fluctuation, so it is necessary to develop efficient storage
options for electricity. One possibility is to store
electricity in the form of hydrogen, which is generated by
the electrolysis technology from renewable electricity. The
polymer electrolyte membrane electrolysis is particularly
suitable for this purpose. It works dynamically and can
react quickly to the fluctuating input power. At present,
this technology is still being worked on in terms of cost
reduction, increased efficiency and longevity. Inparticular,
the optimization of the catalyst coated membrane, typically
Nafion$^{©}$ with iridium on the anode side and platinum on
the cathode side, offers the potential to provide an
improvement in these three areas. With regard to the
mechanical properties, however, there is hardly any
understanding so far. The aim of this work is therefore to
analyze the mechanical properties of catalyst coated
membranes and then to investigate the influence of these
mechanical properties on cell performance. The work is
divided into two parts: ex-situ and in-situ experiments. To
investigate the relevant mechanical properties of catalyst
coated membranes, ex-situ compression tests, swelling tests,
stress relaxation experiments and creep tests under
electrolysis conditions and under compression were carried
out. For the in situ experiments, a pressure cell was
developed with which it was possible to transfer clamping
pressure via a stamp directly to the active cell area. In
addition, different cell designs could be compared. The ex
situ experiments showed a viscoelastic behavior for
Nafion$^{©}$ and catalyst coated Nafion$^{©}$ under
electrolysis conditions. The viscosity of catalyst coated
membranes is 38 \% lower. In the in situ experiments it
could subsequently be proved that these viscoelastic
properties have an influence on the cell performance. Due to
the compression of the membrane, a loss of water occurs,
which results in the performance being reduced above an
optimum clamping pressure of 2.5 MPa. The time dependence of
the compression after a pressure change, the swelling
pressure and the stress relaxation also lead to a change in
clamping pressure and thus performance over time. By
constructive solutions clamping pressure must be kept
constant in the cell.},
cin = {IEK-14},
ddc = {610},
cid = {I:(DE-Juel1)IEK-14-20191129},
pnm = {134 - Electrolysis and Hydrogen (POF3-134) / 1231 -
Electrochemistry for Hydrogen (POF4-123)},
pid = {G:(DE-HGF)POF3-134 / G:(DE-HGF)POF4-1231},
typ = {PUB:(DE-HGF)3 / PUB:(DE-HGF)11},
urn = {urn:nbn:de:0001-2021051014},
url = {https://juser.fz-juelich.de/record/891876},
}