bluuebunny/crossref_metadata_2025_split huggingface dataset:
Healthcare for Lithium-Ion Battery By Multi-in-Situ Electrochemical Impedance Spectroscopy Measurement System
Authors: Shitanda Isao , Hoshi Yoshinao , Honda Keiichiro , Kawado Taiki , Itagaki Masayuki , Aoyagi Shigeo , Fukuizumi Atsuhisa 
Published: February 2020

Electrochemical impedance spectroscopy (EIS) is powerful tool to evaluate a performance of lithium-ion battery because time constants in electrochemical signals can be distinguished with no damage to the electrode. 1,2

Separation of time constants of anode and cathode is desired in the interpretation of impedance spectra of a lithium-ion battery. Multi -EIS measurement is an analysis method in which simultaneous measurements of three impedance spectra (cathode-reference electrode, anode-reference electrode and anode-cathode) are carried out using a suitable reference electrode. The time-constants of anode and cathode from full cell impedance spectra can be separated by using Multi-EIS measurement.
On the other hand, in the case of in-situ EIS measurements for lithium-ion battery, impedance spectra were measured successively during charge or discharge sequence. The in-situ EIS measurement is very useful for monitoring the degradation process of lithium-ion battery during the charge-discharge cycles. 3

In the present study, we developed a multi-in-situ EIS measurement system in which simultaneous measurements of three impedance spectra were carried out during the charge-discharge cycle. The system is based on a newly developed potentiostat which has an integrated high-performance frequency response analyser and data processing software.
The electrode reactions in rechargeable batteries do not satisfy the time stability during the charge–discharge cycles and the low frequency components of the impedance might contain significant errors due to the time variation. In order to compensate the impedance spectrum deviated by the variation of reaction resistance in the charge or discharge, the impedance spectra were measured successively and plotted on the three-dimensional (3D) complex diagram, which has a time axis. The plots were connected by the spline under tension function at each frequency. The cross-section of 3D impedance shell perpendicular to the time axis gives the instantaneous impedance at an arbitrary time, which can be given automatically by using the software. We investigated the influence of SOC and C-rate on impedance spectra of both cathode and anode.
Acknowledgement
This work was supported by JST A-STEP (AS2421666K).
References
1. M. Itagaki, in Nanoscale Technology for Advanced Lithium Batteries, T. Osaka and Z. Ogumi, Editor, p.123, Springer Science+Business Media, New York (2014).
2. T. Osaka, T. Momma, D. Mukoyama, H. Nara, J. Power Souces 205 (2012) 483.
3. M. Itagaki, N. Kobari, S. Yotsuda, K. Watanabe, S. Kinoshita, M. Ue, J. Power Souces 148 (2005) 78.
Ultra-Long-Term Cyclability of Ge/C Nanocomposite Anode for Li-Ion Batteries
Authors: Ngo Duc Tung , Kim Sang-Wan , Park Chan-Jin 
Published: February 2020

Germanium (Ge) is the potential candidate to replace graphite anode material for lithium ion batteries (LIB). Graphite has been used until now as a main anode material in LIB. However, its limited specific capacity cannot meet the world’s growing demand for energy. The volumetric capacity of Ge (7366 Ah/l) is relatively smaller than that of Si (8344 Ahl-1), but Ge has more advantage over Si: the diffusion coefficient of Li in Ge is approximately two orders of magnitude greater than that in Si, intrinsically electrical conductivity of Ge is four order higher than that of Si due to its smaller band gap, and the volume expansion during lithium insertion-deinsertion into Ge is smaller compared with Si. Despite these of promising characteristic, the capacity fading of Ge after some charge/discharge cycles is main problem to be addressed. To improve the cyclability of Ge most studies so far have focused on the use of buffer layer or reducing particle size of Ge. The use of buffer layer has negligible effect on specific capacity of Ge but it will improve significantly the performance of Ge at high rate of charge-discharge owing to improvement in mechanical properties, contact between active material with electrode, and diffusivity of Li.
In this study, we introduced a simple method for synthesis of Ge nano particles interconnected by carbon (GEC). The GEC electrode showed a high specific capacity up to 1339 mAh/g at the rate of C/2, after 50 cycles the specific capacity retained at value of 1321 mA h/g. Even with increasing the charge-discharge rate up to 10C, the specific capacity only decreased about 30 % compared with that at the rate of C/10. The excellent electrochemical performance of GEC electrode was not only due to the buffer layer of carbon but also the interface layer of Ge-carbon. The formation of Ge-C bonding at interface layer is believed to improve the contact between Ge and C, increase the stability during charge-discharge process and reduce stress tension during volume expansion.
The cyclic life of GEC electrode is under-investigation and it can be observed from its initial data that the electrode shows steady performance till the obtained data. However, further cycling data is necessary for making any stamen about the stability in its performance. The initial results demonstrate that the synthesized GEC can be used as an active Li storage material for lithium ion batteries.
High-Energy and High-Power Electrochemical Energy Storage Based on Dual Intercalation/Radical Electrodes
Authors: Wohlmuth Dominik , Fontaine Olivier , Wilkening Martin , Freunberger Stefan A 
Published: February 2020

Li-ion and related battery technologies will be important for years to come. However, society needs energy storage that exceeds the energy and power of common Li-ion batteries.1,2 Many prospective applications of batteries require improving both energy density and rate capability. The simultaneous improvement of these two parameters is not sufficiently addressed by state-of-the-art approaches. High capacity lithium intercalation materials often exhibit poor ionic and electronic conductivity which limit rate capability. Battery electrodes based on polymers bearing organic free radicals allow for exceptionally high rates but fall short in meeting energy density requirements.3,4

Here, we combine the advantages of both storage principles, to form battery electrodes capable of delivering the capacity of the high-energy intercalation material and intermittently the high rate capability of the radical material. First, we must understand the processes that occur in the cell on discharge and charge to fully take advantage of the potential of the concept.
We will discuss recent results on the detailed elucidation of the charge transfer mechanism in the so formed dual radical/intercalation electrodes, materials aspects, thermodynamic and kinetic considerations. We combine synthetic, spectroscopic and advanced electroanalytical methods to gain insight into the governing processes.
1. B. Scrosati, J. Hassoun, Y.-K. Sun, Energy Environ. Sci., 4, 3287 (2011).
2. M.M. Thackeray, C. Wolverton, E.D. Isaacs, Energy Environ. Sci., 5, 7854 (2012).
3. K. Oyaizu, H. Nishide, Adv. Mat., 21, 2339 (2009).
4. T. Janoschka, M.D. Hager, U.S. Schubert, Adv. Mat., 24, 6397 (2012).
Lithium-Ion Batteries Assembled with Electrospun Hybrid Polymer Membrane Containing Reactive Silica Nanoparticles
Authors: Park Sae Rom , Shin Won-Kyung , Kim Dong-Won 
Published: February 2020

Lithium-ion batteries have been rapidly expanding in portable electronic devices, electric vehicles (EVs) and energy storage systems. In lithium-ion batteries, a separator is a critical component which prevents physical contact of the positive and negative electrodes while permitting free ionic transport within the cell. Most of the separators currently used in lithium-ion batteries are based on microporous polyolefin membranes. Although these separators offer excellent mechanical strength and chemical stability, they shrink, soften and even melt at high temperature, which cause short circuiting between electrodes. Furthermore, the large difference in polarity between the non-polar polyolefin separator and the polar organic electrolyte leads to poor wettability. As a result, there is a high resistance when the pores in the separator are not completely filled with liquid electrolyte. In our previous studies, we synthesized silica nanoparticles with vinyl groups, which permitted the surface reaction with vinyl monomers by radical polymerization [1-3]. With the goal of developing high performance separators with high thermal stability, good transport properties and enhanced wettability for non-aqueous liquid electrolytes, we prepared electrospun hybrid polymer membrane based on polyacrylonitrile (PAN) and reactive SiO2 nanoparticles. Due to the presence of reactive silica particles, it could be thermally cross-linked, resulting in good thermal stability and improved wettability for liquid electrolyte. Using the cross-linked electrospun hybrid polymer membranes, we assembled lithium-ion cell composed of carbon anode and LiNi0.6Co0.2Mn0.2O2 cathode. The cycling performances of the cells with cross-linked hybrid polymer membrane were evaluated, and the results were compared to those obtained with a pristine PE separator.

References

1. Y.S.Lee, S.H.Ju, J.H.Kim, S.S.Hwang, J.M.Choi, Y.K.Sun, H.Kim, B.Scrosati, D.W.Kim, Electrochem. Commun., 17, 18, 2012.
2. S.H.Ju, Y.S.Lee, Y.K.Sun, D.W. Kim, J. Mater. Chem. A, 1, 395, 2013.
3. Y.S.Lee, J.H.Lee, J.A.Choi, W.Y.Yoon, D.W.Kim, Adv. Funct. Mater., 23, 1019, 2013.
Investigation of Solid State Diffusion Coefficient Dependency in Lithium Ion Battery
Authors: Ma Miaomiao , Sisk Brian C 
Published: February 2020

The market for electrified vehicles, particularly for low voltage applications, is expected to witness robust growth during the next decade. The emergence of these vehicles will result in the increasing demand of high-power lithium ion batteries. Understanding battery performance over varying temperatures and current pulses plays an important role in battery design, manufacture, and application. In the lithium ion battery performance simulation, the solid state diffusion coefficient is one of the most significant parameters that affect the battery performance.
Solid state diffusion has been previously demonstrated to vary with temperature and state of charge (SOC) [1-2]. Our simulation shows that it also changes with the current density. While the cell ages, the diffusion coefficient decreases as well. With HPPC (hybrid pulse power characterization) data of power cell at different temperatures and different pulse rates, we estimated the diffusion coefficient dependency on current, as seen in Figure1. Using HPPC data from fresh and aged cell, the diffusion coefficient change with time is also summarized.
References:
1. J.N. Reimers, M. Shoesmith, Y.S. Lin, and L.O. Valoen, 160, A1870-A1884, (2013)
2. P.Albertus, J. Christensen, and J. Newman, 156, A606-A618, (2009)
Preparation of NMC622 Cathode Materials Using a Cost Effective Circular Type Reactor for Li-Ion Battery Application
Authors: Song Jung-Hoon , Jeon Dong-Hyup , Hong Jong-Pal 
Published: February 2020

Li(Ni0.6Mn0.2Co0.2)O2 (NMC622) cathode materials have been recognized as the next generation cathode materials due to its higher capacity and lower raw material cost than commercialized cathode materials such as NMC532. Thus, many industrial companies have been made every effort to commercialize and apply the NMC622 to lithium ion battery system such as energy storage system (ESS). However, production cost of NMC622 still has been recognized as expensive material to be applied in the industrial field and it becomes main issues to be overcome. CSTR (Continuous Stirred Tank Reactor) has been widely applied in the industrial field to produce the NMC622 precursor but it has initial long stabilization time as well as low production efficiency. This is caused by the original limitation of CSTR such as the low mass transfer rate and required complete mixing zone to stabilize the system. Thus, in this study, we suggest the novel reactor system that shows the higher mass transfer rate as well as higher production rate than those of CSTR. Developed novel reactor system uses the taylor-couette flows to induce higher mass transfer rate and production efficiency with uniform particle size distribution.
In this study, we synthesized NMC622 using taylor-couette reactor to understand the function and mechanism of the operation. The effect of operating parameters, i.e. pH, operating rpm, and feed retention time, in the taylor-couette reactor, was investigated thoroughly to evaluate the feasibility to produce NMC622 precursor. Produced precursors are characterized using SEM, XRD, ICP, FIB, PSA. Then, cathode materials are prepared and tested using a galvanostatic intermittent titration method (GITT) to understand the electrochemical properties. This study verified that taylor couette reactor is feasible process to be applied to the commercial NMC622 production.
Acknowledgement - This work was supported by the Korea Institute of Energy Technology Evaluation and Planning under the Energy Technology Development Program (20132020101750)
Electrical Property of Nasicon (Na3Zr2Si2PO12) as Solid-Electrolyte for Na/S Battery
Authors: Park Heetaek , Kang Byoungwoo 
Published: February 2020

Na/S battery attracts a lot of attention due to low cost and high energy density for burgeoning large-scale energy storage system. The battery operates at elevated temperature (~300oC), so solid electrolyte which separates molten electrodes is used.1 Beta alumina is widely used as solid electrolyte but it has anisotropic electrical properties and complicated synthesis. In this point of view, Nasicon (Na super ionic Conductor) can be a promising alternative because it has 3-dimensional Na conducting channels and can be obtained by a facile synthesis.
Nasicon (Na1+xZr2SixP3-xO12) has wide composition range (0<x<3) and ionic conductivity of the materials is highest when x equals to 2. However, Nasicon structure goes through transformation from monoclinic phase (Low T) to rhombohedral phase (high T). This phase transformation really affects durability of the solid electrolyte because volumetric change during thermal cycles happens. Thus, the depression of phase transformation is important for high durability.
In this presentation, we will discuss about experimental parameters that influence on the phase transformation and will discuss electrical properties of Nasicon phase using EIS (Electrochemical impedance spectroscopy) measurement
Reference

V. Palomares et al., Energy & Environmetal Science, 5, 5884-5901, 2012
Facile and Scalable Synthesis of 3.9V LiFeSO4F
Authors: Kim Minkyu , Jung Yongjo , Kang Byoungwoo 
Published: February 2020

Cathode materials of Li-ion batteries have been developing to achieve high energy density with superior safety for powering novel applications such as electric vehicles and enegy storage systems. With respect to this consideration, polyanion compounds such as phosphates, fluorophosphates, fluorosulfates have attracted a lot of attention because of their superior safety and high energy density. Among these F-containing compounds, LiFeSO4F compound has been paid much attention as a promising candidate for cathode material in Li ion battery because it shows high energy density with high potential and 151 mAh/g. Especially, tripilite LiFeSO4F phase, one of polymorphs, shows much higher voltage (3.9V Vs. Li+/Li) compared to tavorite LiFePO4F phase (3.6V Vs. Li+/Li) leading to higher energy density. However, the utilization of triplite LiFeSO4F phase has been limited because of complicated synthetic process. Typically, the triplite phase is synthesized by transforming tavorite phase which is formed through topotatic process.[2] Therefore, the key point of challenge is direct synthetic process without tavorite phase transformation. Triplite phase is also more stable than tavorite phase with respect to themodynamic condisderation.[3]

In this presentation, we will discuss the key experimental parameters to obtain triplite phase without going through the phase transfroamtion of tavorite phase and will present the electrochemical properties of the triplite phase obtained by fascile and scalable process.
References
[1] N. Recham &Tarascon, Nature Material 9 (2010) 68 - 74
[2] P. Barpanda &Tarascon, Nature Material 10 (2011) 772-779
[3] A. V. Radha & A. Navrotsky, J. Mater. Chem, (2012), 22, 24446 - 24452
Characterization and Electrochemical Properties of Graphene / Silicon Grafted Composite Materials for Applications in Lithium-Ion Battery
Authors: Weissmann Martin , Crosnier Olivier , Lestriez Bernard , Humbert Bernard , Guyomard Dominique , Agnes Charles , Duclairoir Florence , Bidan Gerard , Brousse Thierry 
Published: February 2020

Density and energy performance of Li -ion batteries are highly dependent on the physical and chemical properties of the electrode materials. The negative electrode materials still offer a large area to explore to improve both capacity and reversibility for lithium storage. In this context, the development of negative electrodes based on silicon has led to numerous researches (1). The high specific capacitance of silicon (3850 mAh.g-1) is the main asset for the use of this material. However, silicon has major drawbacks (volume expansion, irreversible formation of LixSiy alloys,... ) that cause early degradation of the electrodes.
The approach developed in our laboratory is to link the two components by a chemical bond (covalent) between the two materials. This covalent bond, resulting from a chemical grafting of a diazonium salt (4-aminoaniline) allows linking the carbon particles to silicon nanoparticles via a phenyl bridge.
This technique has been used to bond silicon nanoparticles to carbon nanotubes (2) which helped to improve the stability of the electrodes during galvanostatic cycling. The work presented here focuses on a coupling between silicon nanoparticles and graphene sheets.
Graphene is potentially interesting for Li-ion batteries applications, it has good electronic conductivity and its layered structure could promote an increase in the strength of the electrodes. The sheets can act as a buffer when the silicon particles volume increases, thereby helping to maintain the cohesion of the electrode during different cycles of charge and discharge (3). The graphene synthesis was performed according to the Hummers method and leads to particles whose specific surface area is about 200 m² /g (Figure 1).
Electrode materials were characterized by different techniques (TGA-MS, BET, SEM, IR / Raman spectroscopy, cyclic voltammetry, galvanostatic cycles ...) at different stages (graphene modification, graphene / silicon coupling) to show the presence of molecular bridges and determine their influence on the electrochemical behavior of a Li-ion battery. Performance measured 0.16A.g-1 (Figure 2) clearly show a significant improvement in grafted materials compared to a simple mixture of graphene / Silicon materials.

Acknowledgments: The authors thank the French National Research Agency (Graf'N'Stock project) for financial support.

References

(1) M. N. Obrovac, L. Christensen, Electrochem. Solid-State Lett. 7 (2004) A93
(2) C. Martin., O. Crosnier, R. Retoux, D. Bélanger, D. M. Schleich, T. Brousse, Advanced Functional Material 21 (2011) 3524
(3) B. Nguyen, N. Kumar, J. Gaubicher, F. Duclairoir, T. Brousse, O. Crosnier, L. Dubos, G. Bidan, D. Guyomard, B. Lestriez, Adv. Energy, Materials, (2013)3, 1351
Understanding the Surface Structure of LiNi0.45Mn1.55O4 Spinel Cathodes with Aberration-Corrected HAADF STEM
Authors: Amos Charles Dallas , Song Jie , Ferreira Paulo Jorge , Goodenough John Bannister 
Published: February 2020

In order for Li-ion batteries to mature to a level useful for integration into the current or future energy infrastructure, basic problems such as cyclability, cost and rate capability must be overcome. LiNi0.5Mn1.5O4 (LNM), a spinel cathode material, has the advantage of being both cost-effective and a high-rate capable material, but it is plagued with cyclability problems. In the LNM system the main contributor to cycling degradation is the high operating voltage which leads to solid-electrolyte interphase (SEI) formation. We find that excess-Mn doping of this material (LiNi0.5-XMn1.5+XO4where x=0.05) leads to increased cyclability through natural passivation [1]. To understand the exact role that excess Mn plays in the passivation of this cathode material, it is crucial to determine the surface’s atomic structure. This is because the surface structure determines how reactive the cathode will be with the electrolyte during oxidation and reduction cycles.
In order to understand how excess-Mn LNM reacts with the electrolyte, it is critical to understand the different phases that form in this system. In this regard, aberration-corrected high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) was used to identify the surface and bulk structures in the excess-Mn LNM system. A HAADF STEM image of LiNi0.45Mn1.55O4along the [110] zone axis is shown in Figure 1. The image has been deconvoluted for clarity. This confirms the spinel structure (blue) and shows good agreement with STEM simulations in the bulk. Near the surface however, other phases are observed which include the rock-salt phase (green) and an unexpected phase defined here as “ring-type” (red). The rock-salt structure is expected from x-ray diffraction (XRD) results but the ring-type phase; so-called because of the characteristic rings that are formed within the first few atomic surface layers, is not. All three phases are observed near the surface, however only the spinel is found within the bulk of the particles. HAADF STEM enables a detailed characterization of these phases and has led to an important understanding of the cycling degradation mechanisms in the excess-Mn LNM system. In turn, this work enables us to develop a well-suited cathode material for future energy storage that will potentially spur the evolution of the future sustainable energy landscape.

References:

[1] J. Song et al., Chem. Mater. 24 (2012), 3101.

Figure 1