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Transmission measurement of a commercial Li-ion battery was performed using the pulsed neutron beam provided by the Japan Spallation Neutron Source. A high position resolution two-dimensional neutron detector recorded the neutrons that went through the battery sample. The transmission spectra for each partitioned area on the battery sample were fitted by a function taking into account the coherent elastic scattering of neutrons on the electrode materials. Using the fitting results, we succeeded in obtaining the charge/discharge images through the quantitative crystal surface densities. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structures of and phase transitions in the lithium ionic conductor, Li3PS4, which is part of the thio-LISICON (LIthium Super Ionic CONductor) family, were studied using high-temperature synchrotron X-ray diffraction measurements and thermal analysis. There are three transitions among the α, β and γ-phases of this material as a function of temperature. The low-temperature γ-phase transformed to the medium-temperature β-phase at 573K, which then transformed to the high-temperature α-phase at 746K. The γ-phase is iso-structural with β-Li3PO4 (SG: Pmn21) with an orthorhombic cell with a =7.70829(11), b =6.53521(10), and c =6.1365(7) Å at 297K. The β-phase has an orthorhombic cell with a =12.8190(5), b =8.2195(4), and c =6.1236(2) Å at 637K. The apexes of the PS4 tetrahedron are ordered in the same direction in the γ-phase, while in the β-phase, they are ordered in a zig-zag arrangement. The γ-phase showed an ionic conductivity of 3.0×10−7 Scm−1 with an activation energy of 21.3kJmol− 1 at room temperature. The β-phase showed an ionic conductivity of 3.0×10−2 Scm−1 at 500K with an activation energy of 15.5kJmol− 1. [Copyright &y& Elsevier]

A fluoride-ion conductor, γ -PbSnF 4 , was synthesized by the mechanical milling. In addition, β -PbSnF 4 was obtained by aging the γ -PbSnF 4 at 473 K. The electrical conductivity of β -PbSnF 4 is relatively higher than that of γ -PbSnF 4 at 298 K. The crystal structure analysis of γ - and β -PbSnF 4 was carried out using neutron diffraction data. From the obtained occupancies, fluoride ions were located at the F γ (1) normal site (62%) and F γ (2) interstitial site (38%) in γ -PbSnF 4 and the F β (1) normal site (31%), F β (2) normal site (25%), and F β (3) interstitial site (44%) in β -PbSnF 4 . In particular, the number of fluoride ions at the F interstitial site increased after the γ -to- β phase transition: 38% at F γ (2) to 44% at F β (3). It is most likely that the ratio of fluoride ions to vacancies (or the effective carrier concentration) was optimized in the “–F β (1)–F β (3)–F β (3)–F β (1)–” conduction pathways of fluoride ions in β -PbSnF 4 . [ABSTRACT FROM AUTHOR]

K2NiF4‐type Ba–Li oxyhydride (BLHO) transitions to a so‐called hydride superionic conductor, exhibiting a high and essentially temperature‐independent hydride ion (H−) conductivity over 0.01 S cm−1 through the disordering of H− vacancies above 300 °C. In this study, a Ba–Li–Na–H–O oxyhydride system synthesized in which lithium is partially substituted with sodium in BLHO and investigated the effects of Na content on the phase transition behavior and the conductivity. Structural refinements and differential scanning calorimetry experiments confirmed a lowering trend in the phase transition temperatures and decreasing enthalpy changes for the transition with increasing Na content. Substitution of not <40% of Li with Na lowered the degree of ordered vacancies at the H− sites at room temperature and improved conductivities by more than two orders of magnitude in the low‐temperature region (T < 300 °C) before the phase transition. These findings clearly show that introducing Na into the lattice effectively stabilizes the high‐conductive phase of BLHO. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical properties of lithium manganese hydroxyphosphate, LiMnPO4(OH), with the tavorite structure have been investigated to assess its suitability as a cathode material for lithium batteries. Stoichiometric LiMnPO4(OH) was synthesized by an ion-exchange reaction with MnPO4·H2O and LiNO3. Lithium (de)intercalation reaction was observed for the first time in the trivalent LiMnPO4(OH), and it exhibited a reversible capacity of 110mAhg−1 with an average cell voltage of 3.4V (vs. Li) after an irreversible phase change during the first charge process. The crystal structure has been refined at room temperature by neutron and synchrotron X-ray diffraction data using Rietveld method with a space group of P−1. The hydroxy group at a bottleneck may reduce the attraction force between lithium and the bottleneck oxygen ions that thus increase the ion mobility along the lithium diffusion tunnel. [Copyright &y& Elsevier]

Abstract: In order to study the crystal structure of , time-of-flight neutron powder diffraction experiments were carried out at temperatures between room temperature (RT) and 600°C. Rietveld refinement at RT has shown that is monoclinic based on P21/n symmetry and two different types of Ca sites, Ca(1) and Ca(2). All interatomic distances within 3Å were calculated, with the valences of Ca(1) with seven Cand Ca(2) with eight were estimated to be 1.87+ and 2+ by the Zachariasen–Brown–Altermatt formula (bond valence sum). Applying charge neutrality the two charge states of Ca in are [Ca(1)SiO4]2− and Ca(2)2+, respectively. Furthermore, the [Ca(1)SiO4]2− unit has the shortest Ca–O distance, and its length kept constant at 2.23Å at all temperatures. In the short-range structure analysis at RT, the shortest Ca–O bond was also observed in a radial distribution function. These results imply that the [Ca(1)SiO4]2− unit has covalency on the shortest Ca–O in addition to Si–O. [Copyright &y& Elsevier]

X‐ray total scattering measurements are carried out for the typical electrolyte used in lithium‐ion batteries, that is, the mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) electrolyte with LiPF6 salt. The obtained pair distribution function is compared with that of the EC/EMC solvent without LiPF6, to investigate the effect of the Li+ cation on the intramolecular structure. It is found that the peak shift corresponding to the shrinking of the CO bonds is induced by dissolving LiPF6. Also, the peak height becomes lower by the addition of LiPF6. These behaviors are also observed by the X‐ray total scattering measurements for the mixture of EC and dimethyl carbonate (DMC) with and without LiPF6. Also, it is ascertained that such a shrinking is present in EC/DMC electrolytes by means of neutron total scattering. First‐principles calculations on the basis of the density functional theory for isolated EC, EMC, and DMC molecules with the Li+ cation confirm that the shrinking of the CO bond is accompanied by the formation of the solvation structure. The observed structural variations induced by adding LiPF6 will be a good indicator for the formation of the solvation structure. [ABSTRACT FROM AUTHOR]

A new layered perovskite oxyhydride Ba2YHO3 was synthesized via high pressure synthesis. Powder X-ray and neutron diffraction experiments revealed that in Ba2YHO3 the ordered H− and O2− anions form [Ba2H2] rock-salt layers wherein H− conduction is allowed. The conductivity reached 0.1 mS cm−1 at 350 °C, which is higher than that of isostructural Ba2ScHO3 with anion-disordered [Ba2HO] layers. [ABSTRACT FROM AUTHOR]

Thermoelectric material SnSe has aroused world-wide interests in the past years, and its inherent strong lattice anharmonicity is regarded as a crucial factor for its outstanding thermoelectric performance. However, the understanding of lattice anharmonicity in SnSe system remains inadequate, especially regarding how phonon dynamics are affected by this behavior. In this work, we present a comprehensive study of lattice dynamics on Na0.003Sn0.997Se0.9S0.1 by means of neutron total scattering, inelastic neutron scattering, Raman spectroscopy as well as frozen-phonon calculations. Lattice anharmonicity is evidenced by pair distribution function, inelastic neutron scattering and Raman measurements. By separating the effects of thermal expansion and multi-phonon scattering, we found that the latter is very significant in high-energy optical phonon modes. The strong temperature-dependence of these phonon modes indicate the anharmonicity in this system. Moreover, our data reveals that the linewidths of high-energy optical phonons become broadened with mild doping of sulfur. Our studies suggest that the thermoelectric performance of SnSe could be further enhanced by reducing the contributions of high-energy optical phonon modes to the lattice thermal conductivity via phonon engineering. [ABSTRACT FROM AUTHOR]

Abstract: Ibaraki prefecture, the local government of the area for J-PARC site, has decided to build a versatile powder diffractometer (IBARAKI Materials Design Diffractometer) to promote industrial applications for neutron beams in J-PARC. This diffractometer is designed to be a high throughput one enabling materials scientists to use it like the chemical analytical instruments in their material development processes. It covers in d range with at the high-resolution scattering detector bank, and covers with gradually changing resolution. Typical measuring time to obtain a ‘Rietveld-quality’ data is several minutes for the sample size of laboratory X-ray diffractometer. To promote industrial application, a utilization system for this diffractometer is required. We will establish a support system for both academic and industrial users who are willing to use neutron but have not been familiar with neutron diffraction. [Copyright &y& Elsevier]

The capability of La2LiHO3 as a H− conductive solid electrolyte has recently been demonstrated, which has suggested the possibility of developing electrochemical devices based on H− conduction. However, the performance of La2LiHO3 as a solid electrolyte has not yet been fully clarified. In this study, we prepared La2LiHO3 sintered pellets by a conventional solid‐state reaction with LiH flux under ambient pressure and characterized the crystal structure and thermal stability (to moisture, ambient air, and oxygen) by neutron and X‐ray diffraction measurements. The produced sintered pellets exhibited an activation energy of 69.2 kJ/mol, which is consistent with the value of the sample synthesized by the high‐pressure method. The gas‐sealing properties of the sintered La2LiHO3 pellets as the H− conductive solid electrolyte were confirmed by measuring the electromotive force using a hydrogen concentration cell. [ABSTRACT FROM AUTHOR]

Abstract Graphite is widely used as an anode material in almost all Lithium (Li)-ion batteries. Li is easily absorbed into the layer structure of graphite, forming lithium-carbon intercalation compounds Li x C between LiC 6 and C. However, although they are simple binary compounds, their structures have been left unelucidated for a long time, especially for the compounds between LiC 12 and C. This is probably because the Li concentrations are too low to make a big difference in diffraction pattern between these Li-intercalated graphites and pure graphite. It has been known, however, that they have stacked layer structures, which strongly suggests that they are very likely to form modulated structures. Structural analyses of these compounds based on the modulated structure model were successfully performed, comprehensively elucidating all the Li x C structures lying between LiC 6 and C. Graphical abstract Our structural investigation of Li x C crystals confirmed that LiC 6 and LiC 12 structures coexist between LiC 6 (SOC:100%) and LiC 12 (SOC:50%); however, we provided the first ever clarification that, between LiC 12 (SOC:50%) and C (SOC:0%), Li atom disordering and structural modulation take place in their crystals. Image 1 [ABSTRACT FROM AUTHOR]

Abstract All-solid-state lithium batteries have been proposed as solutions to safety issues associated with conventional lithium batteries; consequently, their development is important. To that end, we conducted a material search of solid electrolytes in the Li 4+ x Al x Si 1− x S 4 system. High-temperature (HT) and low-temperature (LT) modifications of novel argyrodite-structured phases were obtained at around x = 0.1 by melt quenching. The HT-argyrodite phase showed the highest ionic conductivity (2.5 × 10−4 S cm−1) at 28 °C, with an activation energy of 40 kJ mol−1; this conductivity value is three orders of magnitude higher than those of Li 4+ x Al x Si 1− x S 4 solid solutions. The relationship between ionic conductivity and phase-type was elucidated. An all-solid-state lithium battery using an HT-argyrodite-phase electrolyte exhibited a discharge capacity of over 120 mAh g−1 and an excellent discharge efficiency of about 100% after the second cycle, demonstrating that this material is suitable for use in practical all-solid-state batteries. Graphical abstract Novel superionic lithium-conductor with a cubic-argyrodite-type structure was synthesized and examined as a solid-electrolyte in the Li–Al–Si–S system. fx1 Highlights • A material search of solid electrolytes in the Li 4+ x Al x Si 1− x S 4 system was conducted. • Novel Li 4+ x Al x Si 1− x S 4 (LASS) superionic lithium conductors were synthesized. • Novel high-temperature (HT) and low-temperature (LT) argyrodite phases were made. • Both HT- and LT-argyrodite type Li 4+ x Al x Si 1- x S 4 materials were produced at x ≈ 0.1. • HT-LASS exhibited an ionic conductivity of 2.54 × 10−4 S cm−1 at room temperature. [ABSTRACT FROM AUTHOR]

Abstract Maximum Entropy Method (MEM) is one of powerful tools for material science. We developed the program Z-MEM for evaluation of electron and nuclear density distribution by MEM analysis and Fourier synthesis. This code is designed by the multi-threading library OpenMP, so that the calculation performance is significantly improvements for MEM analysis. Z-MEM is bundled in Z-Rietveld , which is Rietveld software for X-ray and neutron powder diffraction, via the application programming interface (API). Since Z-MEM have equipped with the graphical user interface operations, users can perform from Rietveld refinement to MEM analysis seamlessly. [ABSTRACT FROM AUTHOR]

Abstract Cobalt trifluoride CoF 3 and Iron trifluoride FeF 3 are known as a G-type antiferromagnetic structure in the R -3 c rhombohedral crystal structure. The neutron powder diffraction study had been reported that Co antiferromagnetic spin direction is parallel to 3-fold crystal axis in CoF 3 whereas Fe antiferromagnetic spin direction is perpendicular to 3-fold crystal axis in FeF 3. However, the resolution of early neutron powder diffractometer is not enough to distinguish between (003) h and (101) h rhombohedral magnetic peaks definitely. We employed high-resolution powder neutron diffractometer(SuperHRPD) at room temperature in MLF, J-PARC. The time-of-flight neutron powder diffractometer distinguishes clearly between (003) h and (101) h magnetic peaks. Then, we confirmed the proposed magnetic structural models of CoF 3 and FeF 3 at room temperature. In a magnetic susceptibility, CoF 3 displays the additional magnetic anomaly at T * = 40 K. We discussed possible weak-ferromagnetism by the interplay of spin tilting and Dzyaloshinski-Moriya interactions. [ABSTRACT FROM AUTHOR]

Abstract We carried out neutron powder diffraction (NPD) experiments on the layered perovskite cobaltite PrBaCo 2 O 5.5+ x (x = 0.24) at Super High Resolution Neutron Powder Diffractometer (SuperHRPD) with a newly installed magnet. At low temperatures, the antiferromagnetic (AFM) reflections of the NPD profile are suppressed whilst ferromagnetic (FM) reflections are enhanced under 14 T magnetic field. The magnetic-field-induced AFM-FM transition reveals the ground-state energy of FM is close to that of AFM. [ABSTRACT FROM AUTHOR]

Abstract The crystal structure of type I clathrate Ba 8 Al 16 Ge 30 prepared by arc melting in argon atmosphere has been studied by using a neutron powder diffractometer from 10 to 900 K. We found that the site preferences in the host structure were relevant to the guest atom features, which agrees with a previous report. Data were analyzed using two models for the Ba atom position in the larger cage (Ba2): an on-center 6 d -site model and an off-center 24 k -site one. The Maximum Entropy Method (MEM) results agree well with the 24 k model and the shape of the nuclear density distribution of Ba2 atom evolves with increasing temperature. [ABSTRACT FROM AUTHOR]

In-situ and operando neutron diffraction are used to analyze the degradation of 18650-type Li-ion cells. Structural characterization of the electrode materials is performed by applying the Rietveld refinement technique to the in-situ data. The structural refinement of both electrodes in the degraded cells indicates that the amount of active Li-ions is reduced by 14.4% and 13.7% in the cathode and anode, respectively. This reduction is good in agreement with the capacity loss determined electrochemically. The results suggest that capacity loss might be mainly caused by loss of active Li-ions due to side reactions such as solid electrolyte interface (SEI) growth. Furthermore, operando measurements are performed to examine the deterioration of the electrode and active materials. Because the structural evolution depending on capacity is increased in the cathode of degraded cells, it is presumed that the cathode active material has deteriorated due to phase transitions. [ABSTRACT FROM AUTHOR]

Novel lithium-ion (Li + )-conducting oxysulfides of the Li 10 GeP 2 S 12 family were found in the ternary Li 2 S–P 2 S 5 –P 2 O 5 system; Li 10 GeP 2 S 12 -type solid solutions with compositions Li 3 + 5 x P 1 − x S 4 − z O z ( x = 0.03–0.08, z = 0.4–0.8) were confirmed. The solid solutions showed ionic conductivities from 4.14 × 10 − 5 to 2.64 × 10 − 4 S cm − 1 at 298 K and a wide electrochemical window of 0–5.0 V ( vs. Li/Li + ). Among the solid solutions synthesized, the purest phase had the composition Li 3.35 P 0.93 S 3.5 O 0.5 ( x = 0.07, z = 0.5). Structural analysis revealed that the novel oxysulfides are isostructural to the original Li 10 GeP 2 S 12 structure and the (P/□)(S/O) 4 tetrahedra, which indicates the presence of cation defects with oxygen substitution in the crystal structure. Electrochemical stability of the oxysulfides was confirmed in the voltage range of 0–5.0 V. The solid-electrolyte interphase (SEI) resistivity and its cycle-dependence evaluation for new materials demonstrated that the oxysulfides had lower resistivities and furnished well-contacted SEI layers during the charge–discharge process. [ABSTRACT FROM AUTHOR]

The ionic conductivities of new perovskite-structured lithium–strontium–aluminum/gallium–tantalum oxides were investigated. Solid solutions of the new perovskite oxides, (Li x Sr 1− x )(Al (1− x )/2 Ta (1+ x )/2 )O 3 and (Li x Sr 1− x )(Ga (1− x )/2 Ta (1+ x )/2 )O 3 , were synthesized using a ball-milled-assisted solid-state method. The partial substitution of the smaller Ga +3 for Ta +5 resulted in new compositions, the structures of which were determined by neutron diffraction measurements using a cubic perovskite structural model with the Pm −3 m space group. Vacancies were introduced into the Sr(Li) sites by the formation of solid solutions with compositions (Li x Sr 1− x − y ☐ y )(Ga [(1− x )/2]− y Ta [(1+ x )/2]+ y )O 3 , where the composition range of 0≤ y ≤0.20 was examined for x =0.2 and 0.25. The highest conductivity, 1.85×10 −3 S cm −1 at 250 °C, was obtained for (Li 0.25 Sr 0.625 ☐ 0.125 )(Ga 0.25 Ta 0.75 )O 3 ( x =0.25, y =0.125). Enhanced ionic conductivities were achieved by the introduction of vacancies at the A -sites. [ABSTRACT FROM AUTHOR]

We report structural effect for Ni-doping in lithium cobalt oxide (LiCoO2) studied by the time-of-flight (TOF) neutron powder diffractions measured at RT. Crystal and local structures of LiCo1−xNixO2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) powders, that were prepared by the solid-state reaction methods, have been respectively examined by using the IBARAKI Neutron Design Diffractometer (iMATERIA) of JPARC and Nanoscale-Ordered Material Diffractometer (NOMAD) of ORNL. The Rietveld refinement for neutron diffraction data of LiCo1−xNixO2 that all have been indexed to the rhombohedral system with trigonal symmetry in the space group R-3m, revealed the lattice parameter c/a ratio that tends to the ideal value as decreasing Ni-contents, while the atomic pair distribution function (PDF) analysis for neutron data of LiCo1-xNixO2 revealed that the Co–O and the Ni–O pair correlation lengths under the first peak of G(r) that respectively vary from 1.88 to 1.9Å and from 1.98 to 2.0Å, with average Ni–O correlation length (1.99Å) seems to be slightly larger than average Co–O correlation length (1.89Å). Rather than that resulted by the Rietveld analysis, the PDF analysis suggested that the diffusion pathways between Co–O in the LiCo1−xNixO2 system remain stable at ~1.89Å for all Ni-contents. [ABSTRACT FROM AUTHOR]

Abstract: Oxygen-deficient Li2MnO3−x (0 < x < 0.19) have been directly synthesized from lithium-rich manganese oxide, Li2MnO3, using metal hydrides (CaH2 and LiH) as reducing agents at reaction temperatures of 255–265 °C. The structure of the reduced phase determined by X-ray diffraction experiments has oxygen vacancies in the layered structure, causing slightly larger lattice parameters than the stoichiometric Li2MnO3. Reversible oxygen insertion and extraction from the deficient structure observed by the TG measurements suggests fast oxygen diffusion in the layered rock-salt structure. The oxygen-deficient phase shows extremely large 1st charge and discharge capacities of 388 and 305 mAh g−1, respectively. [Copyright &y& Elsevier]

Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10−2 S cm−1) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li10GeP2S12 that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm−1 at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window). [ABSTRACT FROM AUTHOR]

Abstract: The oscillatory profile of diffuse scattering of ordered crystal PbF2 is observed by time-of-flight (TOF) neutron scattering measurement. The theoretical expression of diffuse scattering intensity including the correlation effects among the thermal displacements of atoms is used to analyze the diffuse scattering profile of PbF2. The theoretical expression is effective for the analysis of the diffuse scattering data by the TOF measurement. [Copyright &y& Elsevier]

Crystal structures of protonic conductor K3H(SeO4)2 in the phase I (conducting phase) and phase II (room-temperature phase) have been determined using a time-of-flight (TOF) neutron diffractometer VEGA. SeO4 tetrahedra in the phase I were rotationally displaced with the occupancy 1/3 and the crystal structure in the phase II was remain locally. Proton distribution maps were obtained from the maximum entropy method (MEM) describe that the amount of the proton in a hydrogen bond were decline from 87.3% to 21.4% with increasing the temperature and 13.4% of protons exist at inter-layer space. Incoherent quasi-elastic neutron scattering (QENS) experiments performed by LAM80-ET spectrometer yield the QENS spectra of conducting protons. Proton diffusion constants are estimated as 1.9(1) × 10- 10 m2/s at 393 K and 2.1(3) × 10- 10 m2/s at 413 K, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Ibaraki prefecture materials design diffractometer of J-PARC needs a neutron guide to increase beam intensity without sacrificing measurements of powder diffraction with good resolution, PDF analysis and small angle scattering. Non-parallel guides including elliptical ones have been compared with a linear-straight guide using the McStas simulation. The elliptical guide having the exit focal points away behind the sample position is available to increase the neutron flux at the sample but gives a slight lowering of the instrumental resolution. This elliptical guide gives also Garland peaks at short wavelengths that may give large ambiguities in powder diffraction measurements. Therefore, the linear-straight guide is considered as the best choice for this instrument to keep a good resolution and also a relatively high flux. [Copyright &y& Elsevier]

Abstract: The synthesis and crystal structures of nine members of the rock-salt ordered double perovskites Sr2− x Ca x CrNbO6 is presented. The crystal structures of the end members of the series Sr2CrNbO6 and Ca2CrNbO6 were refined using powder neutron diffraction data and are cubic in and monoclinic in P21/n, respectively, in both cases there being considerable anti-site Cr–Nb mixing. Variable temperature and/or composition studies suggest a direct first-order P21/n to transition, a suggestion supported by selected area electron diffraction studies. [Copyright &y& Elsevier]

The rechargeable lithium-ion cell is an advanced energy-storage system. However, high cost, safety hazards, and chemical instability prohibit its use in large-scale applications. An alternative cathode material, LiFePO4, solves these problems, but has a kinetic problem involving strong electron/hole localization. One reason for this is believed to be the limited carrier density in the fixed monovalent Fe3+PO4/LiFe2+PO4 two-phase electrode reaction in LixFePO4. Here, we provide experimental evidence that LixFePO4, at room temperature, can be described as a mixture of the Fe3+/Fe2+ mixed-valent intermediate LiαFePO4 and Li1−βFePO4 phases. Using powder neutron diffraction, the site occupancy numbers for lithium in each phase were refined to be α=0.05 and 1−β=0.89. The corresponding solid solution ranges outside the miscibility gap (0

Abstract: Charge–discharge cycle performance was examined for the cell Li1.08Mn1.92O4/1 M LiPF6 in EC:DEC(1:1)/MCMB. The structure and magnetic properties were determined before and after cycling using X-ray diffraction and SQUID measurements. After both 340 cycles at RT and 150 cycles at 55 °C, single-phase properties were observed for all samples, but samples in the discharged state showed broadening of X-ray diffraction peaks with decrease in the capacity retention ratio. Decreases in lattice parameter and increases in magnetic susceptibility were clearly observed for samples in the discharged state with decreased capacity retention ratios, while small changes in lattice parameter and magnetic susceptibility were observed for samples in the charged state. It was shown that Li intercalation/de-intercalation becomes difficult with cycling in the shallow charged state. Furthermore, it was suggested that the cell capacity decreases because of the disorder in the Li ion conductive pathway caused by the impaired stability of the samples. [Copyright &y& Elsevier]

High-temperature storage of the lithium manganese spinel cathode was examined for Li1.02−xMn1.98O4 using 1 M LiPF6 in EC:DEC (1:1) electrolyte solution. The structure, magnetic properties, and valence state of Mn were determined before and after the storage using Mn K-edge XANES, X-ray diffraction, SQUID, ICP spectroscopy, and electrochemical measurements. After the storage at 80 °C for 6 days, single-phase property was observed at x=0 and 0.96 in Li1.02−xMn1.98O4, while multi-phase property was observed between the compositions, x=0.18 and 0.63. Shallow de-lithiated region near x=0.18 was easily affected by the storage; the Li/Li1.02−xMn1.98O4 cell showed large capacity failure from 111 to 40 mAh/g after the storage which corresponded to the phase transition with the increase in the valence state of Mn after the storage. Magnetic measurement was found to be quite sensitive and effective to detect the subtle structural changes caused by the high-temperature storage. [Copyright &y& Elsevier]

Abstract: Materials and Life Science Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC) is one of the facilities that provided the highest intensity pulsed neutron and muon beams. The MLF computing environment design group organizes the computing environments of MLF and instruments. It is important that the computing environment is provided by the facility side, because meta-data formats, the analysis functions and also data analysis strategy should be shared among many instruments in MLF. The C++ class library, named Manyo-lib, is a framework software for developing data reduction and analysis softwares. The framework is composed of the class library for data reduction and analysis operators, network distributed data processing modules and data containers. The class library is wrapped by the Python interface created by SWIG. All classes of the framework can be called from Python language, and Manyo-lib will be cooperated with the data acquisition and data-visualization components through the MLF-platform, a user interface unified in MLF, which is working on Python language. Raw data in the event-data format obtained by data acquisition systems will be converted into histogram format data on Manyo-lib in high performance, and data reductions and analysis are performed with user-application software developed based on Manyo-lib. We enforce standardization of data containers with Manyo-lib, and many additional fundamental data containers in Manyo-lib have been designed and developed. Experimental and analysis data in the data containers can be converted into NeXus file. Manyo-lib is the standard framework for developing analysis software in MLF, and prototypes of data-analysis softwares for each instrument are being developed by the instrument teams. [Copyright &y& Elsevier]

Li2(NbxMn1–x)O3 is one of the Li‐rich, Mn‐based cathode materials represented by the structural prototype Li2MnO3. Many of these cathode materials crystallize into monoclinic structures; however, our neutron and X‐ray structural analyses revealed that the Li2(NbxMn1–x)O3 compounds adopt NaCl‐type cubic structures in a wide compositional range, at least between x = 5 at.% and x = 50 at.%. In these NaCl‐type structures, Na sites are randomly occupied by the three kinds of metal cations and the Cl sites are solely occupied by O2− anions. These cubic crystals comprise distorted atomic arrangements that are randomly displaced from the atomic positions in a regular NaCl‐type structure. Density functional theory calculations based on these distorted NaCl‐type structure models indicate lower total energy than those of the corresponding monoclinic structures. This result demonstrates that the Li2(NbxMn1–x)O3 compounds can crystallize into such NaCl‐type structures to decrease the crystallization energy. [ABSTRACT FROM AUTHOR]

The study of an all-solid-state TiH2/orthorhombic-La2LiHO3/Ti cell provides conclusive evidence of pure H- conduction. [ABSTRACT FROM AUTHOR]