bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synchrotron Operando x-Ray Computed Tomography of Battery Pouch Cells
Authors: Zenyuk Iryna V. , DeBari Annalisa , Lim Wei Han , Parkinson Dilworth Y. , Xiao Xianghui 
Published: February 2020

X-ray computed tomography (CT) is a promising technique for three-dimensional imaging of batteries. Synchrotrons feature bright x-ray sources that enable micro-scale imaging at a minute time-scale. With hard x-rays the field-of-view is 3 x 3 mm and the x-rays are mostly attenuated by metal current collectors and metal-oxides in the cathode of a battery. Conventional coin cells are not fit for x-ray tomography due to stainless steel being highly x-ray attenuating, even at high energy when it is possible to obtain significant percentage of transmission, view within the coin cell is limited. We demonstrate a design of coin cell with a 5 mm cutout imaging window to enable limited angles x-ray tomography but the resulting images contained high signal-to-noise ratio and the modified coin cells are difficult to handle having electrolyte leaching, electric conductivity and other issues. Several groups have developed a Swagelok cell or an alternative to it, however the design does not allow for high throughput and the compression levels, as well as air-tight sealing present an issue. The current collectors in Swagelok cells have to have graphite inserts, else the alignment of the cell presents an issue because stainless-steel current collector can block the x-ray beam, if the alignment is not perfect. This horizontal configuration is also challenging, as the size of the imaged area is restricted to 3 mm, else the transmission can be an issue, especially for the cathode side because in this horizontal configuration X-rays penetrate 3 mm or more of material from every angle of rotation.
We have developed a high throughput pouch cell design for x-ray CT imaging featuring 1 cm diameter active area. The design enables imaging of lithium metal and lithium dendrites, as well as, interfaces in symmetric and actual pouch cells. The pouch cell design does not require precise alignment as imaging is done in a vertical configuration. The pouch is processed in a similar manner as it would, if designed for electrochemical testing. The time-resolved imaging shows the time-sequence of Li plating and stripping as a function of cycling rate. Unlike optical microscopes, that use large distance between the anode and cathode and have limited field-of-view, the pouch cell features micron-scale thicknesses of components and separation distances that are more representative for actual battery design.
High Voltage Activation of the Nasicon-Type Na4mnv(PO4)3 Cathode Studied By Operando X-Ray Diffraction
Authors: Zakharkin Maxim V. , Drozhzhin Oleg A. , Tereshchenko Ivan V. , Abakumov Artem M. , Antipov Evgeny V. , Stevenson Keith J. 
Published: February 2020

NASICON-type Na3V2(PO4)3 delivers a highly reversible capacity of more than 110 mAh/g, showing a voltage plateau at 3.4 V corresponding to the V4+/V3+ redox couple [1]. In Na3+xMnxV2-x(PO4)3, introduction of Mn(II) lowers the cost of the material and enhances the operation voltage compared to that in Na3V2(PO4)3 [2]. Here, we studied the phase transformation behavior of Na4MnV(PO4)3 upon charge and discharge within different voltage limits.
In Na4MnV(PO4)3 two well-defined steps are observed when charged to 3.8 V [2]. After the increase of the cut-off voltage on charge up to 4.0V the electrochemical behavior on discharge changes, namely instead of two steps as in the case of cut-off at 3.8V a gradual slope is observed [3].
By operando synchrotron X-ray powder diffraction we’ve found that symmetry reduction from rhombohedral to monoclinic occurs immediately after the start of the electrochemical desodiation, with restoring of the rhombohedral phase at 3.8 V [4]. Cycling within 2.5-3.8 V potential range proceeds through both solid solution (Na4MnV(PO4)3↔ Na3MnV(PO4)3) and two-phase (Na3MnV(PO4)3↔ Na2MnV(PO4)3) processes. An additional voltage plateau at ~3.8-4.0 V vs. Na/Na+ is observed, associated with re-distribution of Na cations over available crystallographic positions and “unlocking” of the Na1 site in the rhombohedral phase. Reverse insertion of Na+ cations proceeds via a complete solid solution region. The experimentally observed reversible electrochemical capacity increases by ≈14% after raising cut-off voltage.
This work was supported by the Russian Science Foundation (Grant No. 17-73-30006).

Reference
s
:

[1] K. Saravanan; C. W. Mason; A. Rudola; K. H. Wong; P. Balaya. The First Report on Excellent Cycling Stability and Superior Rate Capability of Na3V2(PO4)3 for Sodium Ion Batteries. Adv. Energy Mater. 2013, 3, 444−450.
[2] W. Zhou; L. Xue; X. Lü; H. Gao; Y. Li; S. Xin; G. Fu; Z. Cui; Y. Zhu; J.B. Goodenough. NaxMV(PO4)3 (M = Mn, Fe, Ni) Structure and Properties for Sodium Extraction. Nano Letters, 2016, 16 (12), 7836-7841
[3] F. Chen; V. M. Kovrugin; R. David; O. Mentré; F. Fauth; J.-N. Chotard; C. Masquelier. A NASICON-Type Positive Electrode for Na Batteries with High Energy Density: Na4MnV(PO4)3. Small Methods, 2018, 2, 1800218
[4] M.V. Zakharkin; O.A. Drozhzhin; I.V. Tereshchenko; D. Chernyshov; A.M. Abakumov; E.V. Antipov; K.J. Stevenson. Enhancing Na+ Extraction Limit through High Voltage Activation of the NASICON-Type Na4MnV(PO4)3 Cathode. ACS Applied Energy Materials, 2018, 11 (1), 5842-5846

Figure 1
Comparing Operando XRD and Dems to Investigate Metal-Substituted LiNiO2
Authors: Bianchini Matteo , Schweidler Simon , Schiele Alexander , Hartmann Pascal , Brezesinski Torsten , Janek Jürgen 
Published: February 2020

LiNiO₂ (LNO) has been introduced as cathode active material for Li‐ion batteries in 1990 [1]. After years of intensive research, it emerged that several instability issues plague the material, so that it was abandoned in favor of isostructural metal‐substituted compounds called NCA (for lithium nickel cobalt aluminum oxide) and NCM (lithium nickel cobalt manganese oxide). These sacrifice a certain amount of specific energy in exchange for stability, durability and safety [2]. With few exceptions, NCA and NCM are nowadays the industrial standard when it comes to automotive applications. However, the continuous push towards electric cars with longer driving range is synonym, for these compounds, with increasing the nickel content (which is already beyond 80%), eventually leading back again to LiNiO₂. For this reason, we synthesized a series of LiNiO2 samples, where Ni is substituted by low amounts of other elements (< 5%). We implement a characterization strategy based on operando XRD, differential electrochemical mass spectrometry (DEMS) and ex situ TEM, enabling us to track, in real time upon battery charge and discharge (i.e., as Li is extracted/inserted from/into LNO, respectively), the evolution of the material´s crystal structure, the transformation of its surface and the evolution of gaseous products. We place particular emphasis on the behavior of LNO at high state of charge (> 4.1 V), where the transition between the hexagonal phases H2 and H3, whose unit cell volume is very different, induces significant mechanical strain in the material [3]. The H2 and H3 phases are also thermodynamically metastable [4] and decompose towards off-stoichiometric Li1-zNi1+zO2, with release of O2[5], a reaction we can observe by DEMS and TEM. With this combined strategy, we aim at understanding which element, if any, can sufficiently stabilize LNO in the charged state.
Bibliography

Dahn, J.R., U. Vonsacken, and C.A. Michal, Structure and Electrochemistry of Li1+-yNiO2 and a New Li2NiO2 Phase with the Ni(OH)2 Structure. Solid State Ionics, 1990. 44(1-2): p. 87-97.

Myung, S.-T., et al., Nickel-Rich Layered Cathode Materials for Automotive Lithium-Ion Batteries: Achievements and Perspectives. ACS Energy Letters, 2017. 2(1): p. 196-223.

Yoon, C.S., et al., Structural Stability of LiNiO2 Cycled above 4.2 V. ACS Energy Letters, 2017. 2(5): p. 1150-1155.

Das, H., et al., First-Principles Simulation of the (Li–Ni–Vacancy)O Phase Diagram and Its Relevance for the Surface Phases in Ni-Rich Li-Ion Cathode Materials. Chemistry of Materials, 2017. 29(18): p. 7840-7851.

Bianchini, M., et al., There and back again - The journey of LiNiO2 as cathode active material. Angew Chem Int Ed Engl, 2018: p. 10.1002/anie.201812472.
Distinguishing Slow Charge Transfer from Slow Desolvation Rate-Determining Step in Ion Intercalation Processes
Authors: Nikitina Victoria A , Stevenson Keith J. 
Published: February 2020

The elucidation of the reaction rate-determining step nature in intercalation processes is essential for the development of approaches for a precise control of rate-limiting factors. Earlier work in the field of the lithium-ion intercalation kinetics has led to the establishment of a general pattern of Butler-Volmer type of charge transfer rate control for a wide range of intercalation materials. However, further research in the field of the development of aqueous Li-ion batteries, as well as alternative to Li+ battery chemistries (Na+, K+, Mg2+ intercalation) resulted in the accumulation of valuable experimental information on the electrochemical intercalation processes for a much wider range of solvents (aqueous solutions, glymes, nitriles, etc.), cations and electrode materials, which suggests that Butler-Volmer type potential dependence of the charge transfer rates is not characteristic for the intercalation processes in solvents, where surface layers formation is not observed, e.g. in aqueous solutions.
In this work, we explore the kinetic patterns of lithium-ion intercalation into two model cathode materials (LiCoO2 and LiMn2O4) and develop criteria for distinguishing between Butler-Volmer slow charge transfer and slow chemical steps. A numerical model for the rate-limiting ion desolvation step is developed and the predictions of the model are compared with the experimental voltammetric and electrochemical impedance spectroscopy data. We show that slow desolvation step results in essential changes in the shape of both cyclic voltammetry and impedance responses with the kinetic resistance vs. potential dependencies being highly informative for the reaction rate control diagnostics. The consideration of the intercalation kinetics in four solvents (water, propylene carbonate, acetonitrile and dimethyl sulfoxide) allows concluding on the influence of the resistivity of surface layer/electrode material interface on the reaction slow step nature.

Figure 1
Opportunities for 3D Zinc Anode Architectures in Aqueous Batteries
Authors: Rolison Debra R. , Parker Joseph F. , Ko Jesse S. , Hopkins Brandon J. , Chervin Christopher N. , Long Jeffrey W. 
Published: February 2020

Zinc-based batteries offer a compelling alternative to lithium-ion batteries thanks to nonflammable aqueous electrolytes augmented by the high energy density of Zn-based batteries. We recently demonstrated that fabricating dendrite-prone zinc into a monolithic porous, aperiodic architecture form-factor suppresses zinc migration and dendrite development. Three structural features of these emulsion–derived Zn "sponge" electrodes physically ensure dendrite suppression: (i) interconnected pathways that maintain long-range electronic conductivity within the electrode volume throughout charge–discharge; (ii) an electrified 3D interface that imparts more uniform current distribution; and (iii) confined internal void volume that controls Zn/Zn2+ precipitation/dissolution dynamics and product redistribution.
The Zn sponge anodes exhibit unprecedented cyclability at high depths-of-discharge (theoretical DODZn), increased specific capacity relative to conventional powder-bed Zn electrodes, and tens of thousands of cycles at low-DODZn pulse-power profiles, as recently demonstrated in prototype Ni–Zn cells [1]. This breakthrough enables the entire family of alkaline Zn batteries (Ni–Zn, Ag–Zn, MnO2–Zn, and Zn–air) to be reconfigured in extensively rechargeable forms, with energy and power characteristics that are competitive with Li-ion batteries.
Our second-generation emulsion protocol improves the volumetric density of the sponge thereby concomitantly improving the energy density and power density of the cell while adding mechanical ruggedness to the anode [2]. We have also introduced additional manufacturing flexibility to sponge fabrication. The potential paths forward for the development and transition of this safer energy-storage technology will be discussed.
[1] J.F. Parker, C.N. Chervin, I.R. Pala, M. Machler, M.F. Burz, J.W. Long, and D.R. Rolison, “Rechargeable nickel–3D zinc batteries: An energy-dense, safer alternative to lithium-ion.” Science, 356, 415–418 (2017).
[2] J.S. Ko, A.B. Geltmacher, B.J. Hopkins, D.R. Rolison, J.W. Long, and J.F. Parker, ACS Appl. Energy Mater. (doi: 10.1021/acsaem.8b01946).
Direct Sodium Hypophosphite Fuel Cell System
Authors: Nikoleishvili Paata , Kveselava Valentina , Kurtanidze Rusudan , Gorelishvili Giorgi 
Published: February 2020

The goal of the presented project is development a new type of direct sodium hypophosphite fuel cell (DSHFC) System, with Sodium Hypophosphite direct oxidation at the CoB2O4 based anode.
Synthesized CoB2O4 was used as a catalyst of sodium hypophosphate oxidation [1,2]. CoB2O4 was annealed at 280˚C - 350˚C demonstrated best catalytic activity. In X-ray phase analysis of the sample show the X-ray diffraction pattern according to the ASTM standard of СoB2O4 (2.88,2.44, 2.03, 1.86 Å).
Sodium Hypophosphite is oxidized in alkaline media. Hypophosphite-ion is adsorbed at metal oxide CoB2O4 surface, hydrogen atom, which is connected with catalyst surface by covalent bond, attenuates P-H bond and finally cleaves it; hydrogen is replaced by hydroxide-ion of water (1, 2) which causes hypophosphite transformation in phosphate. The overall anodic reaction will be (3)
H2O=H++OH- (1)
H2PO2
-ads + OH-ads = H2PO3
-ads+ H++ 2e- (2)
NaH2PO2 + H2O = NaH2PO3 + 2H+ +2e- (3)
The DSHFC anode was made by next steps: the CoB2O4 powder and carbon black XC72 powder 1:3 were mixed in isopropanol alcohol, as a binder was used polytetrafluoroethylene suspension and sonicated during 30 min. A carbon felt was used as an anode substrate and catalytic layer was covered bay spry-gun and heated at 250 oC during 5 min. the figure 1 show the DSHFC construction. The fuel Cell is undivided. As a cathode was used ordinary gas diffusion electrode for O2 reduction. The Anode and the cathode geometric surface area was 4 cm2 (2cm X 2cm)
The Voltage –Ampere characteristics of the Direct Sodium Hypophosphite Fuel Cell was recorded with various concentrations of electrolyte X NaH2PO2 + Y NaOH, electrolyte was feed in to fuel cell by pump, oxygen to the cathode chamber was feed by air compressor (pressure 35-40 mm.H2O).Test were performed at room temperature. External load was changed from 10 000 Ω to 0.1 Ω. Current and voltage of DSHFC was recorded by multi-meters. In optimal conditions, electrolyte 1M NaH2PO2 + 2 NaOH, external load 1 Ω, the current density was 36 mA cm-1, the suitable power density was 13,5 mwt cm-1, open circuit potential was 1v
References
[1] Electroless plating: fundamentals and applications edited by G. O. Mallory, J. B. Hajdu
[2] P.O. Nikoleishvili, at all, Russian Journal of Electrochemistry, 2015, Vol. 51, No. 7, pp. 665–671

Figure 1
Fabrication of High Performance Asymmetric Energy Storage Device with WO3@Graphene By Electrochemical Exfoliation Method
Authors: Das Himadri Tanaya 
Published: February 2020

The demand for batteries and supercapacitors on a single platform has been building up for decades now. The demand for supercapacitors stems from its peak power densities and long-term cycle life. However, transition metal oxides have high theoretical specific capacity to store charge but it drawbacks due to its low electronic conductivity and capacity fading with number of cycles. To overcome these usually metal oxides are embedded with the conductive matrix. The conductive matrix like graphene not only provides path for easy electron movement it also increases the surface area for higher interaction of active electrode materials with electrolyte. Hence it attracts active research pursuits in synthesizing low cost effective electrode materials.
In this work, we report a facile and economic approach to produce tungsten oxidenanospheres embedded in graphene sheets (WO3@G) powders with an improved electrochemical activity.The method consists of exfoliation of graphite cardboard at constant voltage of 10 V in a metal sulphate bath. This ultimately yields black flakes like powders. The WO3@G powders' crystallinity was characterized by XRD which confirmed. The FE-SEM and TEM reveals the formation of nanospheres embedded on the graphene nanosheets. A comparison of the physical and chemical properties was intended with different concentrations of metal sulphate salt solutions. Interestingly, it was found that the yield of graphene also depends on the concentrations of salt bath. The Raman spectroscopy reveals the few exfoliated layers of graphene. We have examined the electrochemical activity of these different electrode materials by studying the supercapacitors properties like cyclic voltammetry, charge-discharge profiles and electrochemical impedance spectroscopy. Thus, we have reached a cheap and effective yield of promising candidate for the electrode materials for energy storage devices. The WO3@G positive electrode was assembled with graphene as negative electrode, sandwiched by gel-electrolyte. These prototype devices were capable of powering consumer electronics applications.
Influence of Water on the Properties of Protic Ionic Liquids
Authors: Stettner Timo , Ray Promit , Kirchner Barbara , Balducci Andrea 
Published: February 2020

Protic ionic liquids (PILs) represent an interesting subclass of Ionic Liquids (ILs), with properties suitable for the realization of different kinds of electrochemical energy storage devices. [1-2] PIL have been proposed as electrolytes for electrochemical double layer capacitors (EDLCs) and lithium-ion batteries (LIBs) [ref]. In the case of EDLCs the use of these ILs appears not to be particularly advantageous due to the presence of a proton on their structure, limiting the operative voltage, and their relative high viscosity, limiting the power performance of these devices. In the case of LIBs, to the contrary, the presence of the proton has a positive influence on the lithium coordination and on the performance at high current densities of IL-based LIBs. [3].
The influence of the water content on the chemical-physical properties of PILs have been investigated in the past, and it has been found that even a few hundred ppm of residual water are strongly changing the properties of these ILs, e.g. they might significantly lower the melting point of PILs. Nevertheless, the impact of the water content on the electrochemical performance of electrochemical energy storage devices containing PILs as electrolytes has not been investigated in detail. These important aspects should be investigated because it could supply valuable information about the development of PIL-based devices.
In this paper we report about the influence of water on the properties of the PIL butylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PyrH4TFSI) containing different amounts of water (0, 1, 2, 3.8 wt%). The viscosity, ionic conductivity, density and electrochemical stability of these PIL have been investigated in detail. Furthermore, the mixtures were utilized as electrolytes for EDLCs containing activated carbon-based electrodes, as well as for LIBs containing graphite anodes and lithium iron phosphate (LFP) cathodes.
The results of this study indicate that small amounts of water have a significant impact on the overall transport properties and stability of PyrH4TFSI. Moreover, they also show that the performance of EDLCs and LIBs containing PyrH4TFSI as electrolyte are considerably changing depending on the water content of the PIL.
Literature:
[1] Menne, Electrochem. Commun. 2013, 31, 39-41.
[2] Vogl, Journal of Materials Chemistry A 2016, 4, 10472-10478.
[3] Brandt, Electrochim. Acta 2013, 108, 226-231.

Figure 1
(Invited) Hard Chemistry: Solid State Electrolytes and Anode Protection for Solid State Lithium and Sodium Batteries
Authors: Nazar Linda F , Kaup Kavish , Zhou Laidong , Kochetkov Ivan , Zhang Zhizhen , Park Kern Ho 
Published: February 2020

The development of safe and high-performance all-solid-state batteries (ASSB) is contingent on creating fast ion conductors that combine high ionic conductivity with good ductility and chemical stability in a large voltage window, while - especially - mastering the interface of the solid electrolyte with the electrode materials. This presentation will examine ways to address these factors with new materials within the crystalline and glassy alkali thiophosphate families, while also shedding light on new design concepts for ion conductivity.
The talk will cover an overview of the state-of-the art in the field, followed by recent findings in our laboratory. Significant increases in conductivity of thiophosphate-halide argyrodites, above that of the parent Li6PS5Cl phase, have been attained by both tuning composition and developing “clean” solution-engineering processing routes to these materials to create materials that exhibit ion conductivities above 1 mS/cm together with good chemical stability. An understanding of superionic conductivity in these and related crystalline and glassy alkali thiophosphates has been achieved using a combination of structural elucidation via single crystal X-ray/powder neutron diffraction, ion conductivity mechanisms via impedance studies and the maximum entropy method, 7Li MAS/PFG NMR, and ab initio molecular dynamics simulations. We correlate crystal structure with ionic conductivity to understand how cation disorder and a frustrated energy landscape affects the conductivity and activation energy. Last but not least, the talk will highlight our work on in-situ Li-ion conductive protective films for lithium metal batteries
(Invited) NMR Studies of Li Metal Dendrite Formation and Coatings
Authors: Marbella Lauren E , Emge Steffen , Grey Clare P. 
Published: February 2020

All solid-state batteries (ASSBs) potentially offer safe electrochemical energy storage as they do not require the liquid organic electrolyte. However, in order to achieve high energy densities that are competitive with conventional lithium ion cells, Li metal anodes are required. Even when nominally pin-hole free ceramic membranes are used, issues surrounding Li microstructural growth and subsequent cell death persist, particularly at high current densities. The use of 7Li magnetic resonance chemical shift imaging to track Li microstructural growth in solid electrolytes will be discussed in this talk. Applications to garnet solid-electrolyte will be described.
We follow the early stages of Li microstructural growth during electrochemical cycling – from the formation of Li on the electrode surface to dendritic Li connecting both electrodes in a symmetrical cell and correlate these changes with electrochemistry (e.g. short circuiting). At low current densities, 7Li MRI detects the formation of Li microstructures in cells before obvious electrochemical signatures indicating their presence are observed.