bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extended Tests of Pyrazolides As Lithium Salts for Lithium-Ion Cells
Authors: Grünebaum Mariano , Hiller Martin Manuel , Wiemhöfer Hans-Dieter 
Published: February 2020

Lithium ion batteries nowadays dominate the market of high power energy storage devices [1]. One of the crucial points for next generation lithium batteries and dual-ion cells for stationary energy storage is the development of lithium salts with enhanced electrochemical stability and without corrosive impact at Al current collectors. Additionally, novel electrolytes for lithium batteries should have a high conductivity and should guarantee long term stability of anode and cathode interfaces as well as lead to stable SEI films. Here, we introduce first examples of a new generation of lithium salts based on pyrazolide anions [2] (cf. Fig. 1). The cyclic anion contains different perfluorinated side chains RF at the 3- and 5-position. Further tests were done with additional modifications at the anionic structure.

Fig. 1: Structures and half-cell cycling with different discharge rates of the anionic pyrazolides and their modified types, RF representing perfluorinated alkyl chains of different lengths.
Both, an efficient synthetic route as well as a thorough characterization of electrochemical stability and conductivity as well as cell tests were carried out. The salts showed an excellent electrochemical stability in non-aqueous solvents up to +5 V vs. Li/Li+. Moreover, cycling of LiFePO4 half-cells revealed structure-conductivity relationships for the novel salts. Both salt-types allowed at least 200 full cycles. Thus, the novel class lithium salts exhibits promising candidates for novel liquid and polymeric electrolyte systems and future safe lithium ion batteries.
The authors acknowledge funding by the German federal ministry of education and research (BMBF) within the project “Insider”, No. 03EK3031A.
[1] M. Winter, R. J. Brodd, Chemical Reviews, 104, 4245, 2004.
[2] M. Grünebaum, H.-D. Wiemhöfer, M.M. Hiller, WO2013135824 A2, 2012.
In-Situ gelled Polymer Electrolytes for Advanced Lithium Ion Batteries
Authors: Di Lecce Daniele , Vitucci Francesco , Palumbo Oriele , Paolone Annalisa , Panero Stefania , Hassoun Jusef , Navarra Maria Assunta 
Published: February 2020

The activities aimed at reducing the safety hazard in lithium batteries have successfully considered the replacement of the conventional, volatile and flammable carbonate-based, liquid electrolytes with more stable polymer electrolytes, obtained in the form of free standing membranes. With respect to other solid polymer electrolytes, such as those based on poly(ethylene oxide), gelled polymer electrolytes (GPEs) have the great advantage of offering high conductivity, i.e. of the order of 10−3 S cm−1, over a wide temperature range, combined with a large electrochemical stability, i.e. extending up to 5V versus Li+/Li [1-3].
Poly(vinylidene fluoride) (PVdF)-based, gel-type membranes have been widely investigated as Li-conducting systems and prepared by conventional solvent-casting procedures [4] or electro-spinning techniques [5].
In this work we report on originally developed, PVdF-based GPEs obtained by in-situ formation of the gel matrix during cell assembly, followed by a lithium salt infiltration step [6]. Particular emphasis was devoted to the study and the optimization of the GPE composition. The substitution of the commonly used LiPF6salt with the fluorine free, bis(oxalato)borate (LiBOB) was investigated.
A detailed thermal and dynamical mechanical characterization was adopted to elucidate the properties of the proposed systems over a wide temperature range. Vibrational spectroscopy revealed interesting molecular interactions among components, mainly. polymer and salt, strongly affecting the stability of the membranes. The electrochemical investigation confirmed high ionic conductivity, a controlled interfacial resistivity versus lithium metal and a good electrochemical stability window.
The feasibility of the in-situ gelled, PVdF-based polymer electrolyte containing the LiBOB salt was demonstrated by successful galvanostatic cyclations of the quoted membrane in different lithium-ion cell configurations, obtained by coupling a Sn-C alloying anode with an high voltage spinel or a LiFePO4cathode.

Acknowledgments

The results of this work have been obtained by the financial support of the European Community within the Seventh Framework Programme APPLES (Advanced, High Performance, Polymer Lithium Batteries for Electrochemical Storage) Project (contract number 265644).

References

[1] F. Croce, G.B. Appetecchi, L. Persi, B. Scrosati, Nature 394 (1998) 456.
[2] G.B. Appetecchi, P. Romagnoli, B. Scrosati, Electrochem. Commun. 3
(2001) 281.
[3] J. Hassoun, S. Panero, P. Reale, B. Scrosati, Adv. Mater. 2 (2009) 4807.
[4] J. Hassoun, P. Reale, Bruno Scrosati, J. Mater. Chem. 17 (2007) 3668.
[5] F. Croce, M.L. Focarete, J. Hassoun, I. Meschinia, B. Scrosati, Energy Environ. Sci.
4 (2011) 921.
[6] L. Lombardo, M. A. Navarra, S. Panero, L. Aguilera Medina, A. Matic, J. Hassoun, J. Power Sources, 245 (2014) 232.
Composition Regulation Prediction of Cathode Materials By First-Principles Calculation
Authors: Li Yang , Lian Fang , Chen Ning , Hao Zhen-jia , Chou Kuo-Chih 
Published: February 2020

The performance of lithium-ion batteries (LIBs) critically depends on the intrinsic properties of the electrode materials. The design and application of novel materials, especially cathode materials, will always be primary to attain performances improvements in LIBs. Mainly commercial cathode materials contain layered (e.g. LiCoO2), spinel (e.g. LiMn2O4) and olivine (e.g. LiFePO4) structures. As known, Part of layered compounds gradually transforms into spinel during cycling, or spinel-like structure forms in the as-prepared layered materials, which results in capacity fading, structure instability and safety problems. The doping technique is accepted as an effective approach to improve the structural stability and electrochemical performance.
First-principles calculation method, which is based on Density Functional Theory (DFT), is used to solve the Schrödinger equation after some rational approximations. The obtained wave function of the system contains a lot of natural information of materials. The computational methods could be the most powerful complementarity for experimental ones, which is helpful for understanding macro-properties and materials design. The First principles calculation method has been applied in the field of LIBs including calculating average lithium intercalation voltage, analyzing intercalation and extraction mechanism, optimizing the structure, etc.
In this work, we modeled the real and virtual layered (LiMO2) and spinel (LiM2O4) phases (M=Sc~Cu, Y~Ag, Mg~Sr and Al~In), then we have comparatively studied the phase stability between the layered phase LiMO2 and spinel phase LiM2O4 (M=Sc~Cu, Y~Ag, Mg~Sr and Al~In), as well as the impact regulation of doping. The phase stability of a specific compound depends on both binding and reaction energy. And the dominant phase between layered LiMO2 and spinel LiM2O4 is close related to the valence state of element M. The location of the compounds with multi-cationic M in the phase dominant figure can be determined by ingredient percentage weighted average method. The regulation of phase stability and impact of multi cationic doping have been proved by the experimental results from references. The phase dominant figure based on the First principles calculation is a power tool to predict the property of LiMO2 layered materials with multi-cationic M.
Rechargeable Lithium Polymer Batteries Assembled with Electrospun Poly(ethylene oxide) Membranes
Authors: Choi Ji-Ae , Jung Yun-Chae , Park Se-Mi , Kim Dong-Won 
Published: February 2020

Solid polymer electrolytes have been paid much attention in rechargeable lithium batteries, due to absence of electrolyte leakage, enhanced safety and design flexibility [1,2]. Solid polymer electrolytes studied to date are mainly based on poly(ethylene oxide)(PEO) containing lithium salts. However, these materials have a major drawback that the ionic conductivity for practical application can only be reached at high temperature, due to the high degree of crystallinity inherent in these complexes at ambient temperature. Because of the inherent drawback, various attempts such as grafting, block copolymerization, interpenetration polymer network have been tried to incorporate PEO into a macromolecular sequence, which inhibits crystallization, while maintaining a low value of the glass transition temperature. In our study, with the aim of developing highly conductive polymer electrolytes with high mechanical strength, we prepared the cross-linked polymer electrolytes using low-molecular weight PEO, which are supported by electrospun nanoporous membrane based on high-molecular weight PEO. In this system, mechanically robust porous membrane with chemical cross-linking can protect against electric short to assure safety reliability and make a flexible thin film. By using these solid polymer electrolytes, the lithium polymer cells are assembled and their cycling performances are evaluated at room temperature.

References

[1] F.M.Gray, Polymer Electrolytes, The Royal Society of Chemistry, Cambridge, 1997.
[2] W.A.Van Schalkwijk, B.Scrosati, Eds., Advances in Lithium-Ion Batteries, Kluwer Academic/Plenum Publishers, New York, 2003.
Ionic Diffusion in the Solid Solution Na3-XKxPO4 (0 ≤ x ≤ 3): Experimental Results and First Principle Calculations
Authors: Guin Marie , Tietz Frank , Bhat Kaustubh , Lustfeld Hans 
Published: February 2020

Na3PO4 is a well-known ionic conductor [1,2] and serves in this work as a starting point to investigate the solid solution Na3-xKxPO4with 0 ≤ x ≤ 3. The aim is to elucidate the impact of potassium ions on the physical properties: crystalline phases, band gaps, activation energies and ionic conductivities.
Various compositions in this solid solution are synthesised by annealing the starting materials at 1200°C according to the Na3PO4-K3PO4phase diagram [3]. Then the crystalline phases, band gaps, activation energies and ionic conductivities are determined experimentally and measured.
Using density functional theory [4] the ground state energies and band gaps are calculated for the various phases. Energy barriers are calculated for various paths of the cations Na+ and K+by using the nudged elastic band (NEB) method [5].
The theoretical and experimental results, especially the simulated energy barriers and the equivalent activation energies, are compared and discussed.
We think that our approach can be applied to more complex solid electrolytes with polyanionic structures like NASICON [6,7].
References:
[1] A. Hooper, P. McGeehin, K. T. Harrison, B. C. Tofield, J. Solid State Chem. 24 (1978) 265-275
[2] J. T. S. Irvine, A. R. West, Solid State Ionics 28-30 (1988) 214-219
[3] I. B. Markina, N. K. Voskresenskaya, Russ. J. Inorg. Chem. 14 (1969) 1188-1192
[4] P. E. Blöchl, Phys. Rev. B 50 (1994) 17953-17979
[5] G. Henkelman, B. P. Uberuaga, H. Jónsson, J. Chem. Phys. 113 (2000) 9901-9904
[6] H.Y.P. Hong, Mat. Res. Bull. 11 (1976) 173-182
[7] H.Y.P. Hong, J.B. Goodenough, J.A. Kafalas, Mat. Res. Bull. 11 (1976) 203-220
LixFeF6 (x = 2, 3, 4) Battery Materials: Structural, Electronic and Lithium Diffusion Properties Presentation Format: Poster
Authors: Schroeder Melanie , Eames Christopher , Tompsett David , Lieser Georg , Islam M. Saiful 
Published: February 2020

Lithium iron fluoride materials have attracted recent interest as cathode materials for lithium ion batteries. The electrochemical properties of the high energy density LixFeF6 (x = 2, 3, 4) materials have been evaluated using a combination of potentials-based and DFT computational methods. Voltages of 6.1V and 3.0V are found for lithium intercalation from Li2FeF6 to α-Li3FeF6 and α-Li3FeF6 to Li4FeF6 respectively. The calculated density of states indicate that Li2FeF6 possesses metallic states that become strongly insulating after lithium intercalation to form α-Li3FeF6. The large energy gain associated with this metal-insulator transiton is likely to contribute to the associated large voltage of 6.1 V. Molecular dynamics simulations of lithium diffusion in α-Li3FeF6 at typical battery operating temperatures indicate high lithium-ion mobility with low activation barriers. These results suggest the potential for good rate performance for lithium iron fluoride cathode materials[1].
[1] M. Schroeder, C. Eames, D. A. Tompsett, G. Lieser, M. S. Islam, Phys. Chem. Chem. Phys., 2013, 15, 20473.
Improvement of Electrochemical Performance of Bulk-Type All-Solid-State Lithium Secondary Batteries By Using Sulfide Solid Electrolyte Thin Films
Authors: Ito Yusuke , Sakuda Atsushi , Hayashi Akitoshi , Tatsumisago Masahiro 
Published: February 2020

All-solid-state batteries using inorganic solid electrolytes are widely studied as next generation batteries. Two types (bulk or thin-film) of batteries have been investigated. Especially, bulk-type batteries, which use composite electrodes of active material and electrolyte powders, are anticipated for power sources with high energy density. Solid electrolyte thin films are useful for bulk-type batteries with an ideal electrode-electrolyte interface. Furthermore, the solid electrolyte contents in composite electrodes can be reduced significantly. We previously fabricated amorphous Li2S-P2S5 and Li2S-GeS2 thin films with high lithium-ion concentrations by pulsed laser deposition (PLD) [1, 2], and this technique was used for coating solid electrolyte thin films on active material particles. Consequently, the energy density of all-solid-state batteries normalized by the total weight of the composite electrode increased [2, 3]. In order to further improve the battery performance, solid electrolyte thin films with higher lithium-ion conductivity are indispensable. We prepared the 33Li4GeS4·67Li3PS4 (mol%) thin film with an ionic conductivity of 1.1×10-4 S cm-1, and the conductivity was increased to 1.8×10-3 S cm-1 by a heat treatment at 200 oC. The all-solid-state cell using LiCoO2 particles coated with the 33Li4GeS4·67Li3PS4 (SE) thin film was charged and discharged with a larger capacity of 67 mAh g-1 than that using non SE-coated LiCoO2 particles. Moreover, the capacity of all-solid-state cell increased to 80 mAh g-1after enhancing the ionic conductivity of SE-coating layer after the heat treatment. The coating of highly-ion conductive solid electrolyte thin films on active material particles is considered to be effective in forming an ideal interface between electrode and electrolyte, resulting in the increase of energy density in bulk-type all-solid-state batteries.
Acknowledgement: This study is financially supported by Toyota Motor Corporation.
References
[1] A. Sakuda et al., J. Am. Ceram. Soc., 93(2010) 765-768.
[2] Y. Ito et al., Solid State Ionics, 236(2013) 1-4.
[3] A. Sakuda et al., J. Power Sources, 196 (2011) 6735-6741.
Visualization of Li Profile in an All-Solid-State Li-Ion Battery By In Situ Electron Holography and Spatially-Resolved Eels
Authors: Yamamoto Kazuo , Yoshida Ryuji , Shimoyamada Atsushi , Sato Takeshi , Matsumoto Hiroaki , Iriyama Yasutoshi , Hirayama Tsukasa 
Published: February 2020

All-solid-state Li-ion batteries (LIBs) have been expected to be next generation energy-storage-devices. However, a large interfacial resistance of Li-ion transfer at the electrode/solid-electrolyte interfaces prevents from the practical use. We have so far developed technique to operate the LIB in a TEM and observed the electric potential change around the interfaces by
in situ electron holography (EH) [1]. However, it is still unclear how the Li-ions are distributed and what kind of relation the Li and the potential profiles have in nanometer scale. In this report, we used spatially-resolved electron energy loss spectroscopy (SR-EELS) to directly detect the Li distribution around the interface, and compared with the potential profile observed by EH.
Figure 1(a) shows a schematic of our battery model sample. The Li2O-Al2O3-TiO2-P2O5-based glass-ceramics sheet (LATP) was used as the solid electrolyte, and the LiCoO2 positive electrode was deposited on one side. The negative electrode was prepared in situ by Li insertion reaction to the negative side LATP [2].
After 50 CV cycles, the negative side region was lifted out by a focused ion beam method and the TEM sample was prepared. The TEM image (Fig. 1(b)) shows a slightly different contrast around the interface. Fig. 1(c) shows the Li spectrum image detected by SR-EELS, the horizontal and vertical axes correspond to the electron energy loss and the sample position of the Fig. 1(b) in the vertical direction, respectively. The Li profile (Fig. 1(d)) was similar to the potential profile (Fig. 1(e)). Therefore, the EH detects the nanometer scale potential change due to the Li insertion reaction. The electronic structure changes of the other important elements (Ti and O) due to the Li insertion will be discussed in this presentation.
This work was supported by the RISING project of the New Energy and Industrial Technology Development Organization (NEDO) in Japan.
[1] K. Yamamoto et al., Angew. Chem. Int. Ed.
49 (2010) 4414 - 4417.
[2] Y. Iriyama et al., Electrochem. Commun. 8 (2006) 1287-1291.
Evolution of Chemical and Morphological Changes of High Capacity Electrode Materials Across Multiple Lengths Scales
Authors: Liu Yijin , Yang Feifei , Nanda Jagjit , Andrews Joy C. , Martha Surendra K , Callender Andrew F , Pannala Sreekanth 
Published: February 2020

Understanding and quantifying the changes in chemical composition as well as morphology of battery materials under electrochemical cycling is fundamental to their long cycle life and safety1-2. This is particularly true for high energy density lithium-manganese rich cathodes which transitions from a high voltage layered–layered phase to a defect type spinel phase under constant electrochemical cycling. In this study we combine the full-field transmission X-ray microscopy (TXM) and the X-ray absorption near edge structure (XANES) to spatially resolve and map the accompanying chemical phase change and morphology of a high voltage lithium-ion cathode composition, Li1.2Mn0.525Ni0.175Co0.1O2, (LMR-NMC)3
at a resolution down to 30 nm over a fields-of-view of several tens of microns. 2D TXM-XANES imaging was conducted on a series of samples recovered at different stages of the battery cycling, showing that the material experiences phase segregation of various transition metal species from the particle bulk to surface4. Energy-resolved 3D morphology and quantification analysis with elemental information suggested that the distribution of three transition metal is heterogeneous and the surface of material particle constantly evolves with electrochemical cycling with varied average concentration of Mn, Co and Ni compared to particle internal.
These results will be compared with results obtained from confocal ex-situ Raman mapping for pristine and cycled LMR-NMC composite cathodes. Raman results provide important information regarding the chemical homogeneity of the electrodes with respect to active material, binder and carbon additive distribution and their changes under high voltage electrochemical cycling.

Florian Meirer, Jordi Cabana, Yijin Liu, Apurva Mehta, Joy C. Andrews and Piero Pianetta, J. Synchrotron Rad,. 18, 773 (2011).

Wen-Chin Chen, Yen-Fang Song, Chun-Chieh Wang, Yijin Liu, Darius T. Morris,Piero A. Pianetta, Joy C. Andrews, Hung-Chun Wud and Nae-Lih Wu, J. Mater. Chem. A
1, 10847. (2013).

Surendra K. Martha, Jagjit Nanda, Gabriel Veith Nancy J. Dudney, J Power Sources 199, 220 (2012)

Fei fei Yang et al. Under preparation (2014)
Li9Mg3[PO4]4F3
and Li2Mg[PO4]F: Crystal Structures and Ionic Conductivities
Authors: Ben Yahia Hamdi , Shikano Masahiro , Takeuchi Tomonari , Kobayashi Hironori 
Published: February 2020

In oxide electrolytes, crystalline phosphate with NASICON (NaSuper Ionic Conductor)-type structures such as Li1+xAlxTi2
−x(PO4)3 (LATP) and Li1+xAlxGe2
−x(PO4)3 (LAGP) are known as excellent Li ion conductors. Perovskite Li0.5
−3xLa0.5+xTiO3 (LLT) exhibits the high level of bulk conductivity of 10−3 S cm−1, but LATP and LLT electrolytes have Ti element in crystalline structure, and thus transition metal such as Ti is easily reduced by lithium metal negative electrode; it is thus difficult for these electrolytes to use in lithium metal batteries.
Recently, we started the systematic study of crystal structure and the electrochemical properties of fluorophosphate phases which do not contain transition metal elements. Indeed, in the ternary phase diagram LiMgPO4-LiF-Li3PO4, two new lithium rich phases have been discovered (Li2Mg[PO4]F and Li9Mg3[PO4]4F3). Li2Mg[PO4]F crystallizes with the well-known Li2Ni[PO4]F-type structure, whereas the Li9Mg3[PO4]4F3 crystallizes with a new-type of structure. Li9Mg3[PO4]4F3 exhibits an ionic conductivity of 10-4 S cm-1 at 300 °C, which is much higher than that of Li3VO4 (σ
300
°C =1.6x10-6 S cm-1), γ-Li3PO4 (σ
300
°C =2.2 ´ 10-8 S cm-1) or Li2SO4 (σ
300
°C =2 ´ 10-7 S cm-1). This new phase would be also of great interest as positive electrode for Li-ion batteries if Mg2+ could be replaced by Fe2+ or Mn2+cations [1].
[1] Crystal structures of the new fluorophosphates Li9Mg3[PO4]4F3 and Li2Mg[PO4]F and ionic conductivities of selected compositions, H. Ben Yahia, M. Shikano, T. Takeuchi, H. Kobayashi, M. Itoh,
J. Mater. Chem. A (2014)DOI:10.1039/C3TA15264B.