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Volume 7
Biosensors Journal
ISSN: 2090-4967
Electrochemistry 2018
June 11-12, 2018
Page 38
conference
series
.com
June 11-12, 2018 | Rome, Italy
4
th
International Conference on
Electrochemistry
Ralph Gilles, Biosens J 2018, Volume 7
DOI: 10.4172/2090-4967-C1-001
How neutrons as a probe for
in situ
and
in operando
measurements support the understanding of
electrochemistry in Li-ion battery research
F
or a better understanding of the electrochemistry in batteries a huge demand emerge for
in situ
and
in operando
characterization
methods. Due to the high penetration depth and high sensitivity of neutrons to light elements as lithium such a probe is more
and more attractive in the last decade. This contribution gives an overview how neutrons with their unique properties contribute in
the development of new battery cells. During charging and discharging of NMC/graphite cells the intercalation of Li in the graphite
layers can be observed
in situ
with neutron diffraction (ND) as such measurements are sensitive to detect LiCx phases as LiC
6
and LiC1
2
during the intercalation/de-intercalation process. Under fast charging conditions and low temperatures the appearance
of Li plating can be studied. A correlation of C-rates and Li plating is investigated by means of voltage relaxation and
in situ
ND.
Batteries consisting of lithium iron phosphate (LFP) are often used for stationary energy storage systems. Here neutrons provide the
answer why various types of graphite result in losses of the storage capacity. On larger scales of >50 micrometer neutron imaging
(radiography and tomography) enables a non-destructive view inside the cell to make visible for example how the electrolyte filling
with the distribution of the electrolyte in the cell between the layer stacks in a pouch cell takes place. The use of neutron induced
prompt gamma activation analysis (PGAA) is a powerful tool to describe the capacity loss of the cell caused by tiny metal deposition
on the graphite anode after charging/discharging processes. The method of neutron depth profiling (NDP) is suited to study near
surface phenomena as the Li distribution in electrodes. A new set-up for NDP is currently under development to improve the space
resolution and to measure with a time resolved mode.
Recent Publications
1. Zinth V, V Lüders C, HofmannM, Hattendorf J, Buchberger I, Erhard S V, Rebelo Kornmeier J, Jossen A and Gilles R (2014)
Lithium plating in lithium-ion batteries at sub-ambient temperatures investigated by
in situ
neutron diffraction. Journal of
Power Sources 271:152-159.
2. V Lüders C, Zinth V, Erhard S V, Osswald P J, Hofmann M, Gilles R and Jossen A (2017) Lithium plating in lithium-ion
batteries investigated by voltage relaxation and
in situ
neutron diffraction. Journal of Power Sources 342:17-23.
Ralph Gilles
Technical University of Munich, Germany