Thursday 11 July 2013, Moorfoot & Kilsyth Rooms, 11:00-13:00
Batteries and Fuel Cells
In operando neutron and X-ray imaging studies on Li-Ion-Batteries
M Muehlbauer1,2, O Dolotko1,2, A Senyshyn2, K Nikolowski3 and H Ehrenberg3
1
TU-Darmstadt, Germany, 2Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), Germany, 3Karlsruhe Institute
of Technology (KIT) / IAM-ESS, Germany
The transfer project “in operando studies of fatigue in commercial Li-ion batteries by neutron tomography and
diffraction” is financially supported by the Deutsche Forschungsgemeinschaft DFG. It is part of the Research
Collaborative Centre 595 “Electrical fatigue in functional materials”. Our group concentrates on the investigation of
fatigue mechanisms of commercially available Li-ion-batteries. This presentation will cover neutron and X-ray
imaging techniques used to gather information on a rather macroscopic scale of several micrometers. Neutron
radiography and tomography enable to visualize a three-dimensional distribution of lithium inside of Li-ion-batteries
and its exchange between the anode and cathode during charge and discharge. X-rays show different interaction
with matter and give complementary information to our measurements carried out with neutrons. They offer a higher
spatial resolution and enhanced contrast for the inactive materials like the copper current collector. Thus X-ray
radiography and tomography are perfectly suited to follow alterations of the internal cell geometry due the
expansion and contraction of the electrode materials caused by intercalation and deintercalation of lithium. During
the measurements all cells are kept under real operating conditions. The electrochemical state of the cells is
controlled and monitored by dedicated equipment. Furthermore the non-destructivity of these investigations allows
us to monitor the fatigue behaviour of the cell during the whole battery life time. In combination with other methods,
e.g. neutron diffraction, it is possible to gain a deeper insight of fatigue mechanisms causing reduced battery life
time and capacity fade.
1D-to-2D Na-ion diffusion in the battery-type material NaxCoO2 studied by neutron scattering
M Mansson1, F Juranyi2, J Sugiyama3, J Gavilano2, V Pomjakushin2, B Batlogg4, H Rudolf Ott4, E Pomjakushina2,
M Mena2, D Sheptyakov2, K Kamazawa5, Y Sassa4 and M Medarde2
1
École polytechnique fédérale de Lausanne, Switzerland, 2Paul Scherrer Institut, Switzerland, 3Toyota Central
Research and Development Laboratories (TCRDL), Japan, 4ETH Zürich, Switzerland, 5Comprehensive Research
Organization for Science and Society (CROSS), Japan
Layered transition metal oxides have been studied extensively both for their correlated electronic properties as well
as for applications e.g. Li-ion batteries. Recently these two fields have been unified under the framework of the
layered NaxCoO2 family where Na-ion vacancy order [1] as well as dynamics [2,3] has been shown to tailor lowtemperature magnetic and thermoelectric properties. We have recently performed T-dependent high-resolution
neutron diffraction (ND) measurements on NaxCoO2 powder samples. Our data display a clear "melting" of the
ordered Na-ion planes in two steps, involving an intriguing crossover from 1D to 2D Na diffusion [4]. It is evident
that the onset and evolution of ion-diffusion is intrinsically linked to a series of subtle structural transitions, which
open the diffusion pathways. Further, we have also performed pressure dependent measurements, which indicate
[5] a very interesting, yet counterintuitive, increase of Na-diffusion with decreasing c-axis length. Our current ND
measurements together with previous μ+SR work on battery materials [6]; have established a novel and detailed
insight into the ion diffusion processes in this group of compounds. This allows us to contemplate and consider the
possibilities for tuning fundamental physical properties as well as solid state engineering of energy related materials
with improved functional properties.
[1]
[2]
M. Roger et al., Nature 445, 631 (2007)
T. F. Schulze et al., Phys. Rev. Lett. 100, 026407 (2008)
ICNS 2013 International Conference on Neutron Scattering
[3]
[4]
[5]
[6]
M. Weller et al., Phys. Rev. Lett. 102, 056401 (2009)
M. Medarde et al., arXiv:1301.5827
M. Månsson et al., publication in progress
J. Sugiyama et al., Phys. Rev. Lett. 103, 147601 (2009)
Relaxation phenomena in superionic and molten cuprous iodide
Y Kawakita1, S Tahara2, M Nakamura1, T Kikuchi1, Y Inamura1, K Maruyama3, K Nakajima1, S Ohira-Kawamura1,
Y Yamauchi1, W Kambara1, S Takeda4 and M Arai1
1
J-PARC Center, JAEA, Japan, 2University of the Ryukyus, Japan, 3Niigata University, Japan, 4Kyushu University,
Japan
CuI is well-known to exhibit superionic behaviour in the high temperature solid state, where the mobile Cu ions
migrate between intersticial sites in the sublattice of immobile halogen ions [1]. From static structure analyses[25], Cu-Cu correlation has a first sharp diffraction peak (FSDP) at 0.9 Å-1 in the structure factor and Cu-Cu
distribution significantly penetrates into the nearest neighboring shell which is mainly contributed by Cu-I
correlation. Large density fluctuations of Cu ions exist and Cu ions bonded with each other look form onedimensional streams, which can be interpreted as superionic behavior of Cu ions even in the molten state [3,4].
Inelastic and quasielastic neutron scattering measurements for superionic and molten phases of CuI have been
performed in a wide Q-E range using AMATERAS cold disk chopper neutron spectrometer installed at BL14 in MLF, JPARC. We will report analysis on relaxation phenomena of superionic melts in close relation to the static structure
and phonon excitation in solid phase
[1]
[2]
[3]
[4]
[5]
J.B. Boyce et al., Phys.Rev. B23 (1981) 2876.
Y. Waseda et al., J. Phys. Soc. Phys. Condens. Matter 12 (2000) A195.
S.Takeda, et al., Physica B 385-386 (2006) 249-251.
Y. Kawakita et al. J. Phys.:Condens. Matter 19 (2007) 335201.
F. Shimojo et al., J. Phys. Jpn. 73 (2004) 2148.
Ion migration processes in lanthanum barium gallate studied by neutron scattering
N Jalarvo1,2, O Gourdon2, Z Bi2, D Gout2, L Stingaciu1, M Ohl1, M Paranthaman2
1
Forschungszentrum Jülich GmbH, Germany, 2Oak Ridge National Laboratory and International Centre for Diffraction
Data, USA
One of the current objectives of fuel cell research is to develop a stable and efficient ion conducting electrolyte for
intermediate temperature applications (400 - 700 °C). Ceramic oxides have been on focus as ionic conductors for
decades, with many advantages compared to the other candidates. In these materials oxide ion conductivity usually
occurs via oxygen vacancies. Protonic defects, responsible for proton conduction, can be incorporated from humid
atmosphere into the oxygen vacancies. Recently attention has been moving towards oxides containing tetrahedral
moieties, because they exhibit improved properties. Fundamental mechanisms acting on atomic scale determine
the macroscopic behavior of materials, and therefore understanding of the atomic scale processes is an essential
key to set directions for developing future materials. We have studied a material consisting of tetrahedral network of
GaO4, i.e. La1-xBa1+xGaO3-d and its hydrated form. Impedance spectroscopy and neutron scattering experiments at a
high flux neutron spallation source were performed to study the atomic scale migration processes of oxide ions and
protons/deuterons. We will show how anharmonic atomic displacement parameters and Fourier difference maps
delivered from the neutron powder diffraction in combination with high resolution quasielastic incoherent neutron
spectroscopy can be used to identify elementary steps of ion conduction processes in atomic-scale. Complete
migration paths as well as the activation energies for each elementary step will be presented.
ICNS 2013 International Conference on Neutron Scattering
X-ray and neutron diffraction studies of borohydrides containing heavy elements
I Llamas Jansa1,2, J Olsen2, A Kydland Lysdahl2, M Sørby2, C Frommen2 and B Hauback2
1
ESS: European Spallation Source, Sweden 2IFE: Institute for Energy Technology, Norway
The crystal structure determination of hydrogen containing compounds where heavy elements like transition metals
or rare earth elements are in close proximity to light elements like boron and hydrogen relies heavily on the
combination of X-ray and neutron scattering methods. One example is the crystal structure of LiCe(BH4)3Cl. This
compound is the first example of a solvent-free rare earth borohydride containing different cations and anions. It
crystallizes in the cubic space group I-43m (Z = 8) with lattice constant a = 11.5916(1) Å and contains tetranuclear
anionic clusters [Ce4Cl4(BH4)12]4- balanced by lithium ions. The clusters have a Ce4--Cl4 core that takes up the shape
of a distorted heterocube [1]. The high lithium ion conductivity makes this material a potential candidate as solid
electrolyte for battery applications [2]. Finally, we present a detailed overview on the structural diversity of solventfree borohydrides containing rare-earth elements, with special emphasis on compounds formed by ytterbium. We
will demonstrate that the whole series of lanthanide borohydrides possesses a huge structural diversity that can be
rationalized on the basis of changes in the experimental conditions, size of the rare-earth ions and their electronic
configuration.
[1]
[2]
C. Frommen, M.H. Sørby, P. Ravindran, P. Vajeeston, H. Fjellvåg, and B.C. Hauback:J. Phys. Chem.
C(2011), 115, 23591-23602.
Morten B. Ley, Dorthe B. Ravnsbæk, Yaroslav Filinchuk, Young-Su Lee, Raphaël Janot, Young Whan Cho,
Jørgen Skibsted, and Torben R. Jensen;Chem. Mater., 2012, 24 (9), 1654-1663.
In-situ SANS and QENS studies of the structure and dynamics of water in operating Nafion proton exchange
membrane fuel cells
M Maccarini1, S Lyonnard1, A Morin1, B Frick2, J Ollivier3, L Porcar3 and G Gebel1
1
CEA, France, 2Institut Laue Langevin, France, 3Institut Laue Langevin, France
The proton exchange membrane fuel cells (PEMFC) are promising electrochemical energy converters. The control of
the water management and proton conduction mechanisms in operating fuel cells are key issues for the
optimization of the fuel cell performance and lifetime.
Aim of our work is to study the proton and water dynamics in the Nafion membrane in situ during fuel cell operation.
This is a complex task since the water dynamics in the membrane is highly sensitive to membrane water content[1],
external conditions such as temperature and gas humidity[2]. In order to study the dynamics of water and proton
with inelastic neutron scattering (NS), we must be in operating conditions that guarantee homogeneity of the water
distribution within the membrane[3,4].
A novel PEMFC was developed to be able to perform in-situ small-angle and inelastic NS experiments. We present
here the SANS study performed on D22 at ILL aimed at quantifying the homogeneity of the water distribution as a
function of the operating conditions (temperature, gas flow, gas stoechiometry, current density, voltage). The
optimized conditions have been chosen on the basis of the SANS experiment, and used for the QENS experiments
that were performed on IN5 at ILL. A comparison of the QENS spectra obtained at equilibrium (no current) and
during operation of the fuel cell will be presented. The effect of the electric field on the local dynamics of protons will
be discussed.
[1]
[2]
[3]
[4]
Perrin et al. J. Phys. Chem. C 2007, 111, 3393-3404
Deabate, S. et al. Energy & Environmental Science 2012, 5(10), 8824-47
Xu, F. et al. Journal of the Electrochemical Society, 2007, 154(12), B1389-98
Morin, A. et al. Fuel Cells 2012, 12(2), 156-161
ICNS 2013 International Conference on Neutron Scattering
CaFeO2.5 a case study for the understanding of low temperature oxygen mobility
A Piovano1, M Johnson1, G Agostini2, M Ceretti3, M Zbiri1, H Schober1, J Kulda1, C Lamberti2 and W Paulus3
1
Institut Laue-Langevin, France, 2University of Torino, Italy, 3University of Montpellier, France
Oxygen ion conductors at low temperatures are materials of major interest for a series of applications as fuel cells,
battery electrodes and sensors. For this reason the discovering of oxygen reversible intercalation into brownmilleritetype SrMO2.5 (M = Co, Fe) in an electrolyte at RT is considered of paramount importance [1-3]. On the contrary, the
iso-structural CaFeO2.5 material does not conduct oxygen at RT, but only at high temperatures (over 1000 K).
Inelastic neutron scattering (INS) studies on cold TOF instrument IN6 at ILL, combined with ab-initio (DFT) molecular
dynamical calculations on the homologous SrFeO2.5 and CaFeO2.5 have been employed to explain this significant
difference in their temperatures for oxygen mobility. In the last years we were able to synthesize large high purity
CaFeO2.5 single-crystals [4]. Their analysis by means of INS experiments on thermal three-axis instruments IN3 and
IN8 allows us to follow, in a wide temperature range, the modifications of its phonon dispersion. We have evidence
of the existence of a low energy mode related to a modification of oxygen dynamics.
[1]
[2]
[3]
[4]
A. Piovano et al., J. Phys. Chem. C., 115, 1311 (2011)
W. Paulus, et al., J. Am. Chem. Soc., 130, 16080 (2008)
R. Le Toquin, et al., J. Am. Chem. Soc., 128, 13161 (2006)
M. Ceretti et al., CrystEngComm, 14, 5771 (2012)
ICNS 2013 International Conference on Neutron Scattering