bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rechargeable Aqueous Lithium-Ion Battery Zn/LiFePO4 for Large Scale Energy Storage
Authors: Yesibolati Nulati , Umirov Nurzhan , Koishybay Aibolat , Omarova Marzhana , Doskumbay Abilkhaiyr , Kurmanbayeva Indira , Zhang Yongguang , Zhao Yan , Bakenov Zhumabay 
Published: February 2020

1.
Introduction

Rechargeable aqueous lithium batteries (RALBs) are promising alternative to bypass safety issues of lithium-ion batteries (LIBs) with organic electrolyte. Furthermore, fast lithium diffusion in aqueous electrolyte media could allow for the operations under high electric current conditions required for high power supply [1]. J. Dahn et al
[2] reported on a VO2/LiMn2O4rechargeable aqueous battery, based on the “rocking chair” concept adopted from LIBs. However, this type of batteries had serious issues with cyclability.
Here, we report for the first time on a system comprising an intercalation LiFePO4(LFP) cathode and a Zn metal anode in an aqueous electrolyte, and on large-scale RALB based on this concept with enhanced cycle performance and energy density.

2. Experimental

All electrochemical tests were carried out using galvanostat/potentiostat VMP3 (Biologic) and two-electrode Swagelok-type cells and a rolled cylindrical battery configuration (ca. 600 mAh per cell). The commercial LiFePO4 (Hohsen Co, Japan) powder and zinc foil (Good Fellow, England) were used as cathode and anode, respectively. Graphite (Sigma Aldrich) and stainless steel (SUS316) rods were used as current collectors for the positive and negative sides, respectively. Absorptive glass mat (AGM) acted as a separator. The electrolyte was a mixed aqueous solution of zinc and lithium salts. Galvanostatic charge/discharge cycling was performed at various current densities from 0.6 C to 60 C (1 C corresponds to a current density of 170 mA g-1) at room temperature and the voltage cutoffs 1.0-1.4 V vs. Zn2+/Zn.

3. Results and discussion

The electrochemical performance of Zn|LFP is presented in Fig. 1. The battery exhibited discharge capacities of 75 mAhg-1 and 43 mAhg-1 at high current densities of 30 C and 60 C, respectively, and maintained excellent stability and coulombic efficiency with a capacity of 102 mAhg-1 after 300 cycles when cycled at 6 C (Fig. 1b).
The large scale battery (stack of cylindrical cells) showed 590 mAh/cell capacity at the initial cycle and could maintain 550 mAh/cell capacity after 10 cycles as shown in Fig. 1c. The further details of these studies will be presented at the Meeting.

Acknowledgments

This research was supported by the “Nazarbayev University Corporate Fund of Social Development” grant.

References

1. Wei Tang, Yuping Wu, Kian Ping Loh, Energy Environ. Sci., 6 (2013) 2093–2104
2. W. Li, J.R. Dahn, D.S. Wainwright, Science 264 (1994) 1115-1118.
Surface Enhanced Raman Microscopy in the Study of Li-Ion and Li-Air Battery Interfaces
Authors: Hardwick Laurence J , Aldous Iain , Cabo-Fernandez Laura 
Published: February 2020

Surface layers on lithium battery electrodes play a vital role in affecting battery performance, ageing mechanics and safety. Particularly, the solid electrolyte interphase (SEI), which is a protecting layer formed on the negative electrode of lithium-ion batteries as a result of electrolyte decomposition, significantly impacts upon irreversible charge “loss”, rate capability, cyclability, exfoliation of graphite and safety.
The investigation of surface layer formation is also important in the understanding of the operation of the lithium-oxygen battery. The non-aqueous lithium-oxygen cell is one of a host of emerging opportunities available for enhanced energy storage [1]. Unlike a conventional battery where the reagents are contained within the cell, the lithium-oxygen cell uses dioxygen from the atmosphere to electrochemically form the discharge product lithium peroxide. Degrees of reversible oxidation and formation of lithium peroxide has been demonstrated in a number of non-aqueous electrolyte classes, mostly notably in dimethysulfoxide based electrolytes [2], thus making the lithium-oxygen cell a potential energy storage device.
The design and optimisation of techniques based on both surface-enhanced Raman spectroscopy (SERS) and shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) for ultra-sensitive analysis will be presented in the study the formation and composition of interfaces on lithium battery electrode materials. SHINERS, first reported by Prof. Tian and his co-workers [3] provides, as does SERS, an ultra-sensitive technique for understanding the formation and composition of interphases/ passivation layers on electrode materials and is considered to be a powerful technique for in situ surface analysis. The highest enhancement of Raman scattering using SHINERS appears at the junction between the particles and substrate as hot spots with magnitudes of up to 4x108 fold. Raman signals can be greatly enhanced by surface plasmon resonance generated on the surface of gold or silver nanoparticles. In SHINERS, the gold nanoparticles are coated with ultrathin silica or alumina layer. The inert shell is expected to be thin, uniform, fully enclosed and optically transparent so that it can retain the surface enhancement and ensure that there is no direct contact between the probed substance and the gold core. The shell-isolated nanoparticles are then spread onto the electrode surface and assembled into an in situ Raman electrochemical cell.
The poster will present our groups recent results of the spectro-electrochemistry studies of dioxygen in non-aqueous electrolytes, as well the use of SHINERS to understand model electrode interfaces within Li-ion battery electrolytes.
References:
1. P.G. Bruce, S. Freunberger, L.J. Hardwick, J.-M. Tarascon, Nature Mater. (2012) 11 19
2. Z. Peng, S.A. Freunberger, Y. Chen, P.G. Bruce, Science, (2012) 337 563
3. Li et al. Nature (2010) 464 392
Discharge Reaction Mechanism of FeS2 Cathodes in Na Batteries: First-Principles Calculations
Authors: Momida Hiroyoshi , Oguchi Tamio 
Published: February 2020

Several types of materials have been extensively studied to find suitable electrode materials for Na secondary batteries, and recently pyrite-FeS2 has attracted much interest as a cathode material of Na batteries [1]. However charge and discharge reactions in the Na/FeS2 batteries, which are governed by conversion mechanisms, are not fully understood yet especially concerning intermediate states involved in the reactions.
In this study, by using first-principles calculations for probable phases in Na/FeS2 conversion reactions, we theoretically estimate electromotive forces (EMFs) characterizing battery performances. To study atomic structure changes during the reactions, we calculate x-ray absorption spectra (XAS) of Na/FeS2 before and after Na discharges. Obtained EMF and XAS are compared with experimental results [1], and atomistic discharge reaction mechanisms in Na/FeS2 battery systems are discussed.
We use stable crystal phases as model structures of Fe-S, Na-S and Na-Fe-S systems. Calculations are based on the density functional theory within the generalized gradient approximation adopting the all-electron full-potential linearized augmented plane wave method, and XAS spectra are computed on the basis of Fermi’s golden rule with the one-electron ground states [2]. All the computations are done using the HiLAPW code.
We first calculate EMFs assuming stable Na-S crystals as a final product of discharge reactions of Na/pyrite-FeS2. Calculated results show that the most likely final product is Na2S+Fe generating EFM of about 1.2V vs. Na, consistent with the experimental results. We further investigate multi-step reactions considering Fe-S, Na-S and Na
x
FeS2 (x = 1 and 2) models as intermediate products. All assumed multi-step reactions are energetically higher, indicating that the assumed intermediates can be minor products relative to the two-phase form as FeS2-Na2S. Among the assumed multi-step reactions, we find energetically acceptable two-step reactions that produce FeS and Na
x
FeS2 intermediate phases, and the two-step reactions can give EFMs close to the two-phase average 1.2V vs. Na. Thus FeS as well as Na
x
FeS2 may be plausible intermediate products. Comparison of the calculated XAS spectra at the S K-edge with the experimental ones [1] also shows that the intermediates of FeS+Na2S likely exist during the reactions.
[1] A. Kitajou, J. Yamaguchi, S. Hara and S. Okada, J. Power Sources 247, 391 (2014).
[2] T. Oguchi and H. Momida, J. Phys. Soc. Jpn. 82, 065004 (2013).
Application of Small Angle Neutron Scattering for In Situ Measurements of Li-Ion Batteries
Authors: Seidlmayer Stefan , Zinth Veronika , Gilles Ralph , Hattendorff Johannes 
Published: February 2020

Small-angle scattering is a commonly used to gain informations about the nanostructure of the investigated materials (i.e. size, volume and shape of particles). Also, neutrons are a powerful tool for in-situ investigations because of their high material penetration depths. Therefore SANS is well suited for studying any changes of these parameters inside closed battery cells under operation. Up to now only a few publications exist dealing with the SANS method for batteries and battery materials. This is mainly caused by the fact that only new developed batteries provide a reasonable thickness for transmission measurements necessary for the applied method.
In 2012 Bridges et al. used a Li||Graphite coin cell for an in-situ SANS experiment, observing the growth of the anodic SEI-layer [1], while for example Nagao et al. used the method to investigate the Li-intercalation mechanism in carbon host materials [2].
However, one major drawback in these experiments is that only cells with Li-metal as counter electrode were used.
In our approach we assemble experimental cells consisting of the same anode and cathode materials as used in commercial cells and perform in-situ SANS experiment during charging/discharging. The cells are assembled as pouch bag or coffee bag cells.
We report on our measurements with the SANS-1 instrument at Heinz Maier-Leibnitz Zentrum (MLZ), Garching. In-situ small-angle neutron scattering data of NMC||Separator||Graphite cells was collected during a complete charging and discharging cycle. In addition single battery components were measured separately to distinguish the various component signals. The in-situ data shows a variation of the integrated total scattering intensity in dependence of the state of charge. The quite noticeable step in the curve can be associated with the volume changes of the cathode or anode materials caused by the Li-intercalation process. Combining the different data sets a feasible interpretation of the charging/discharging process will be presented.
Our future aim is to further develop the in-situ small-angle neutron scattering technique to be able to monitor aging and electrode deterioration processes without the need to open the cells.
[1] Bridges, C. A., X.-G. Sun, J. Zhao, M. P. Paranthaman and S. Dai. "In Situ Observation of Solid Electrolyte Interphase Formation in Ordered Mesoporous Hard Carbon by Small-Angle Neutron Scattering." The Journal of Physical Chemistry C, 2012, 116(14), 7701-7711.
[2] Nagao, M., C. Pitteloud, T. Kamiyama, T. Otomo, K. Itoh, T. Fukunaga, K. Tatsumi and R. Kanno. "Structure Characterization and Lithiation Mechanism of Nongraphitized Carbon for Lithium Secondary Batteries." Journal of The Electrochemical Society, 2006, 153(5), A914-A919.
Local in-Operando Temperature Measurements Across the Interfaces of a Lithium Ion Battery Cell Using Microscopic Thermography
Authors: Schneider Michael , Heubner Christian , Junker Nils , Lämmel Christoph , Michaelis Alexander 
Published: February 2020

The predicted widening of applications for lithium ion batteries is still lagging behind due to several disadvantages mostly concerning safety and reliability hazards caused by the heat evolution during rapid charging and discharging. For targeted material development, design optimization and battery management a detailed and fundamental knowledge of the heat evolution mechanisms and the heat transfer on the micro and macro scale is obligatory.
Most of the investigations published in literature focus on the heat evolution in lithium ion batteries and dealing with integral measurement techniques at commercially available systems. The interpretability of the measurements is rather difficult due to the complexity of the multi composite system.
For a detailed and fundamental research on the heat evolution mechanisms in the individual battery components cathode, separator/electrolyte and anode the authors developed a special electrochemical cell for microscopic in-operando thermography. Using a thermography system with high spatial and temperature resolution we were able to measure the spatially resolved temperature evolution across the interfaces of anode/separator/cathode.
Differences in the heat evolution rates of cathode, separator and anode depending on the electrochemical reactions, the state of charge and the applied electric current density are identified by the experiments. The heat evolution was investigated depending on the charging-discharging rate. The main heat evolution mechanisms are:
· the superiority of reversible heat effects due to the electrode reactions for near equilibrium conditions
· the dominating effect of Joule heating for high charging-discharging rates.
In the investigated battery setup the LiCoO2 cathode can be identified as the most decisive component for the overall heat evolution in the cell according to the ohmic resistance and remarkable high reversible heat effects.
Li7La3Zr2O12-Based Solid Electrolytes for Li Batteries with Voltages Beyond 5 Volts
Authors: Uhlenbruck Sven , Tsai Chih Long , Finsterbusch Martin , Hammer Eva , Bitzer Martin , Van Gestel Tim , Buchkremer Hans Peter 
Published: February 2020

Today’s commercial electrolytes used in lithium ion batteries, e.g. aprotic solvents with Li salts and possibly gel or polymeric stabilization, do not have sufficient electrochemical stability for high voltage cells around and above 5 V. Some sulfide, oxide and phosphate solid state materials exhibit remarkable Li ion conductivity (which can be further increased by increasing operating temperature), thus enabling them as promising candidates for solid-state Li electrolytes [1]. From the oxide class of materials, garnet-like materials based on Li7La3Zr2O12 were chosen for this publication due to their reasonable lithium ion conductivity (high 10-4 Scm-1 range at room temperature), and their stability against air and also humidity so that they can be processed in ambient conditions.
Li7La3Zr2O12 where Li or Zr sites are partially substituted by Aluminum, Tantalum or Yttrium, with simultaneously optimized Li content and high total Li ion conductivity were prepared and characterized with regard to crystal structure. One focal point was put on the phase formation and especially on the ratio of the cubic to tetragonal phase. The material was subsequently processed to electrolyte foils with lateral dimensions of up to 7cm×7cm and analyzed with respect to conductivity and electrochemical properties including operation as an all solid state cell using high voltage cathode materials.
References
[1] N. Kamaya et al. Nature Mat. 10 (2011) 682-686, doi: 10.1038/NMAT 3066
Early Identification of the Li15Si4 Phase Using in-Situ Synchrotron XRD
Authors: Beattie Shane D , Weaving Julia S. , Thapar Vijay , Conner Leigh D , Aniol Maria , Nagai Aisaku , Evans Stuart , McKiernan Mary 
Published: February 2020

In-situ synchrotron X-ray powder diffraction (SXRD) was performed on a Li-Si pouch cell on the high-energy beamline (I12) at Diamond Light Source. The high photon energies provided by the synchrotron allowed the beam to pass directly through the Li-Si pouch cell while still providing high resolution SXRD data. Furthermore, the large flux of the synchrotron beam allows high temporal resolution SXRD data to be collected. Fast acquisition time and high resolution SXRD patterns allows for accurate identification of the onset of Li15Si4 formation.
Obrovac and Christensen [1] showed that the fully lithiated phase for silicon at room temperature is Li15Si4. They also showed that the Li15Si4 phase is formed below 50 mV (vs. Li), which typically occurs at the end of silicon lithiation. Li and Dahn [2] used in-situ XRD to show that the Li15Si4 phase does not occur until high capacity (> 3500 mAh/g) and low voltage (< 50 mV).
The results discussed above clearly show that formation of the Li15Si4 phase can be capacity dependent. One could also theorize that the formation of Li15Si4 is voltage dependent. To further elucidate the effect of voltage on the formation of the Li15Si4 phase in-situ SXRD was performed on Li-Si cells at voltages below 50 mV.
In-situ SXRD data is shown in Figure 1 as a function of intensity (left ordinate) and as a ‘waterfall plot’ vs. time (right ordinate).
Figure 1 clearly shows that the silicon peak recedes as a function of time (and capacity), while the Li15Si4peak grows.
To better quantify the formation of the Li15Si4 phase Figure 2 shows the evolution of the volume fraction of Li15Si4 as a function of time (lower plot abscissa) and capacity (upper plot ordinate).
Figure 2 shows that the Li15Si4 phase can be observed almost immediately. As capacity increases the volume fraction of Li15Si4 continues to increase. These results show that the Li15Si4phase can be formed very early if the voltage at the silicon electrode is below 50 mV.

References:
[1] M. N. Obrovac and Leif Christensen, Electrochemical and Solid-State Letters, 7 (5) A93-A96, 2004
[2] J. Li and J. R. Dahn, Journal of The Electrochemical Society, 154 (3), A156-A161, 2007
Development of Thin Glass-Ceramic Electrolytes Via a Sol-Gel Route
Authors: Lorrmann Henning , Hartmann Sarah , Röder Manuel , Frech Florian , Kapuschinski Martina , Sextl Gerhard 
Published: February 2020

Due to their high energy densitites lithium-air and lithium-sulfur are the most promising battery technologies. Both systems inhibit substantial drawbacks, though. The dendrite formation on the lithium anode and subsequent shorting of the cell is still unsolved since the first market introduction of rechargeable lithium-batteries in the early 1990s. With common liquid electrolytes dendrite formation cannot reliably be prevented. However, solid electrolytes with a high shear modulus effectively inhibit this effect.[1]

Solid NASICON-type electrolytes (e. g. Li1+xAlxTi2-x (PO4)3, LATP) offer a high ionic conductivity at room temperature and a high anodic stability. The low stability against metallic lithium, due to the reduction of the transition metal (e. g. Ti4+), requires an intermediary layer.[2] Additionally, a reliable concept for the integration of a free standing and thick (> 50 µm) “electrolyte-sheet” has yet to be proven.
In our work, dense electrolyte layers with a thickness below 1 µm were prepared by sol-gel methods (Figure 1). It was intended that a wet chemical deposition of cathode material onto the sintered electrolyte should reduce the interface resistance and that the resistance could be further optimized by varying the deposition and sintering conditions. The electrolyte/electrode interface was analyzed by means of SEM and depth-profiling XPS. Temperature dependent XRD allows for the analysis of the sintering process in situ. The interface resistance was tested galvanostatically and by electrochemical impedance spectroscopy. Electrochemical tests on the electrolyte were performed with sputtered platinum electrodes. The (spectro) electrochemical characterization (Figure 2) of thin-film electrodes on TCO coated glass substrates was realized in specially designed test cells.
This poster presents the first results on the sol-gel deposited glass ceramics as electrolyte, thin film cathodes and the interface between both components. Future work will focus on the anode/electrolyte interface (Lithium/polymer/glass-ceramic) and finally a working solid-state cell.
[1] W. Xu, J. Wang, F. Ding, X. Chen, E. Nasybulin, Y. Zhang, J.-G. Zhang, Energy Environ. Sci.
2014.
[2] P. Knauth, Solid State Ionics
2009, 180, 911–916.
Failure Mode Analysis of Li-Ion Batteries Using In Situ Scanning Electron Microscopy
Authors: Hovington Pierre , Lagacé Marin , Marceau Hugues , Clément Daniel , Dontigny Martin , Trottier Julie , Guerfi Abdelbast , Mauger Alain , Julien Christian M , Zaghib Karim 
Published: February 2020

High cycle life is a key component that any lithium-ion battery technology must achieve in order to obtain a commercial success. In this regard, multiple electrochemical (Impedance, ASI, floating current, etc.) and non-electrochemical techniques (XRD, FT-IR, SEM/TEM, etc.) are used and developed. The most complete techniques involved measurement while the battery is cycling (in situ experiment). Among them, in-situ SEM/TEM is able to focus on the same region/particle over the all range of oxidation/reduction. Hydro-Quebec has developed a complete expertise for in-situ techniques, especially in situ SEM.
Lithium Polymer Battery (LPB), an all solid battery, is the preferred battery configuration for SEM in-situ experiment. We present in Figure 1 micrographs taken during in-situ experiment of a LPB (Li/PEO based SPE/Li1.2V3O8 based cathode) showing the variation in thickness for the Li, SPE and cathode layers with the cell voltage. Only the Li thickness shows an important variation during plating and unplating. The Li plating rate can also be measured. This experiment can clearly be used to better understand the Li plating mechanism.
In figure 2 we present micrographs taken during an in-situ SEM cycling of a Li/PEO based SPE/SiO cell using backscattered electron signal. We clearly see an important decrease in the BSE intensity as a function of the cell voltage as a result of the Si phase transformation upon cycling (upon Li ‘insertion’, the BSE intensity is lower and the particle becomes darker). We also note that a region of the big particle remains white (i.e. the Li did not have sufficient time to ‘diffuse’ inside their core region). This result explains the rather low capacity observed with such particles and it gives evidence that the system is out of thermodynamic equilibrium. This in-situ experiment also shows no cracking of the relatively big SiO particles since the voltage was kept higher than 0.1V (stop at the Li22Si7 phase instead of Li22Si5) when compared to previous results [1]. We will also present in-situ SEM of nano-Si particles that did not suffer any cracking, but agglomerate (electrochemical sintering), which results in a more rigid and fractured electrodes [2]
This presentation will also used in-situ SEM to obtain a better understanding of the failure mechanism of new electrode materials, including Li-S.
References:
[1] http://batt.lbl.gov/blog/research-tasks/in-situ-sem-seeing-battery-cycling-in-action/?utm_source=rss&utm_medium=rss&utm_campaign=in-situ-sem-seeing-battery-cycling-in-action
[2] Hovington et al, (2014) ‘in situ Scanning electron microscope study and micriostructural evolution of nano silicon anode for high energy Li-ion batteries’, Journal of Power Sources 248, 457-464