bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cation-Disordered Lithium Transition Metal Oxides for Rechargeable Lithium Batteries
Authors: Lee Jinhyuk , Urban Alexander , Li Xin , Ceder Gerbrand 
Published: February 2020

Layered lithium transition metal oxides, such as LiCoO2, have been one of the most important classes of cathode materials for rechargeable lithium batteries [1,2]. In these materials, lithium and transition metal ions are well-segregated to form distinct layers which alternate in their crystal structure [1,2]. In general, well-layeredness in their structure has been considered necessary for high lithium mobility in the materials, and cation mixing has been observed to result in poor cyclability by slowing down lithium diffusion [3,4]. Such understanding and observations may have led researchers to disregard cation-disordered lithium transition metal oxides as promising cathode materials.
Recently, we have identified a material (Li1.211Mo0.467Cr0.3O2) whose behavior questions our understanding of the effect of disorder on lithium transport [5]. This material forms as a layered rocksalt, but transforms to a disordered rocksalt after just a few charge-discharge cycles. Nevertheless, it cycles very well, exhibiting a specific capacity well above 250 mAh/g, which is rarely achieved even in well-layered materials. Using ab initio computations and Monte-Carlo simulations, we explain the performance of Li1.211Mo0.467Cr0.3O2, and propose a design paradigm for cation-disordered oxides as cathode materials [5].

[1] M. S. Whittingham, Chem. Rev. 104, 4271-4302 (2004).
[2] J. B. Goodenough, Y. Kim, Chem. Mater. 22, 587-603 (2010).
[3] K. Kang, Y. S. Meng, J. Bréger, C. P. Grey, G. Ceder, Science
311, 977-980 (2006).
[4] A. Rougier, P. Gravereau, C. Delmas, J. Electrochem. Soc. 143, 1168-1175 (1996).
[5] J. Lee, A. Urban, X. Li, D. Su, G. Hautier, G. Ceder, Science, 9 January 2014 (10.1126/science.1246432).
Structural Analyses of Amorphous MoS3 Electrode after Charge-Discharge Measurements in All-Solid-State Lithium Secondary Batteries
Authors: Matsuyama Takuya , Hayashi Akitoshi , Tatsumisago Masahiro , Ozaki Tomoatsu , Togawa Yoshihiko , Mori Shigeo 
Published: February 2020

All-solid-state lithium batteries using inorganic solid electrolytes are expected to be highly safe because of elimination of flammable components such as organic liquid electrolytes. Further improvement of the electrode active materials with high capacity and excellent cyclability is needed. Sulfur is expected to be positive electrode active materials of next-generation batteries because sulfur has a high theoretical capacity. Therefore, high capacity of the batteries can be achieved by using active materials with a large content of sulfur. However, sulfur has low electronic conductivity. We thus focus on a transition metal sulfide with high electronic conductivity. Moreover, amorphization of active materials is potentially capable of achieving higher capacity and cyclability because of open and random structure in amorphous materials.
MoS2 crystal was practically used as a positive electrode in lithium metal batteries [1]. Electrode properties of amorphous MoS3 prepared by pyrolysis of (NH4)2MoS4 have been investigated in an organic liquid electrolyte [2]. A liquid-type cell with amorphous MoS3 electrode shows the reversible capacity of 400 mAh g-1. Thus, amorphous MoS3 active materials are an attractive positive electrode with high capacities for lithium batteries. In this study, structure and electrochemical properties of amorphous MoS3in all-solid-state cells were evaluated.
Amorphous MoS3 was prepared by mechanical milling of the mixture of molybdenum metal and sulfur. The obtained active materials were applied as a positive electrode to all-solid-state cells with Li2S-P2S5electrolytes [3]. In order to analyze the structure of the positive electrode, XRD and HR-TEM were performed for the electrodes before and after the charge-discharge measurements.
The samples prepared by mechanical milling showed no peaks attributable to starting materials in the XRD patterns. Raman bands attributable to amorphous MoS3 were observed in the milled sample. Those structural analyses suggest that amorphous MoS3 was prepared by mechanical milling. The initial discharge capacity of the all-solid-state cell with amorphous MoS3 was approximately 760 mAh g-1. The cell with amorphous MoS3 electrode retained the discharge capacity of about 670 mAh g-1for over 60 cycles. The XRD profile obtained from the electrode after the 1st charge-discharge measurement was almost identical to that from the initial electrode. HR-TEM revealed that amorphous structure was maintained after the 1st cycle.
Reference
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J. Electrochem. Soc.,134 (1987) 580.
[3] A. Hayashi et al.,
Electrochem. Commun. 5 (2003) 111.
Capacity Fading Machanism for Both Electrodes in Prismatic Lithium Ion Batteries with Long Calendar Life
Authors: Cai Sendan , Dai Yang , Xie Jingying , Yang Weijing , Wang Ting 
Published: February 2020

lithium-ion batteries have been produced on a large scale and used extensively
in the commercial mobile devices, typically in the so-called 3C (cellular phones, camcorders, and computers) industry since they have high working voltage, large capacity, and no memory effect compared with other candidates such as metal-hydride batteries and nickel-cadmium batteries .[1]. Besides, lithium ion batteries are also good candidates in applications for electric vehicles (EV) and hybrid electric vehicles (HEV) if both electrodes are well matched in kinetic characteristics at high charge and discharge current rates.
The first commercial lithium ion battery developed by Sony in 1991 was composed of LiCoO2 as the cathode and carbon as the anode. One-dimensional lithium ion transport path means lower energy barriers and high ionic conductivity which makes layered-structure materials such as LiCoO2, LiNixCoyM1-x-yO2 ( M = Mn, Al, etc), and some carbon materials attractive to the researchers as well as the business developers although they suffer from structure changes during cycling.[2,3,4,5]
For a specific cell, the cathode and anode may contribute differently to the capacity fading since both electrodes possess different electrochemical properties. However, most literatural reports focused on one single electrode, i.e. either the cathode or the anode, when discussing the capacity fading machanism of a specific cell.
Here, we monitor the EOCV(end of charge voltage) and EODV (end of the discharge voltage ) of the both elecrodes in one cell in-situ to figure out the main fading factor of a LiNi0.8Co0.15Al0.05O2 / graphite prismatic cell at different calendar stages during cycling at the rate of 0.2C. And we find that, during the former 100 cylces, the cathode material is the controlling factor contributing to the capacity fading while the lateral 100 cycles see the controlling factor changing from cathode to the anode

[1] Abraham K M. Directions in secondary lithium battery research and development[J]. Electrochimica Acta, 1993, 38(9): 1233-1248.
[2] Muto S, Sasano Y, Tatsumi K, et al. Capacity-Fading Mechanisms of LiNiO2-Based Lithium-Ion Batteries II. Diagnostic Analysis by Electron Microscopy and Spectroscopy[J]. Journal of The Electrochemical Society, 2009, 156(5): A371-A377.
[3] Zheng S, Huang R, Makimura Y, et al. Microstructural Changes in LiNi0. 8Co0. 15Al0. 05O2 Positive Electrode Material during the First Cycle[J]. Journal of The Electrochemical Society, 2011, 158(4): A357-A362.
[4] Yoon W S, KYUNG Y C, McBreen J, et al. A comparative study on structural changes of LiCo1/3Ni1/3Mn1/3O2 and LiNi0. 8Co0. 15Al0. 05O2 during first charge using in situ XRD[J]. Electrochemistry communications, 2006, 8(8): 1257-1262.
[5] Bang H J, Joachin H, Yang H, et al. Contribution of the structural changes of LiNi0. 8Co0. 15Al0. 05O2 cathodes on the exothermic reactions in Li-ion cells[J]. Journal of The Electrochemical Society, 2006, 153(4): A731-A737.
3D Silicon Electrode Based on Stainless Steel Metal Fibril Current Collector for Flexible Lithium-Ion Batteries
Authors: Song Seonghyun , Kim chang-Hyeon , Choi Jaecheol , Ryou Mhyung-Hyun , Lee Yong Min 
Published: February 2020

Although silicon (Si) has been extensively investigated for one of the next high capacity anode materials, large volume changes during cycling and low electric conductivity result in poor cycling and rate capability. As a result, Si/carbon composite materials having Si content less than 10% are being introduced for commercial lithium-ion batteries (LIBs). This cannot be a good way to utilize Si for electrochemical systems. Therefore, as a different point of view, we try to fully use Si capacity by modifying Si electrode structure with metal fibril current collector. Comparing to flat metal current collector, circular-type fibril current collector having the same Si loading value can mitigate volume-changing stress like Fig. 1. Inspired by this promising fact, we try to use stainless steel metal fibril (SF) of a diameter of 10 um as a current collector. And then Si is sputtered upon SF by using radio-frequency sputtering.
The Si coating thickness is controlled to be about 1um equivalent to the loading level of 0.2 mg/cm2 (0.6 mAh/cm2), which is considerably high comparing to conventional thin film Si electrode. The Si/SF electrode can not only deliver 3000 mAh/g at a 300mA/g during the initial cycling, but also maintain 1600 mAh/g at a 2000mA/g rate after 200 cycles without delamination of Si from SF current collector. The rate capability is also astonishing to give 1300 mAh/g at a 12000 mA/g. Finally, when the Si/SF electrode is applied for flexible lithium-ion batteries, the cycle performance is well maintained similarly to the original case.

References

[1] D.J. Lee et al, Journal of Materials Chemistry A, 10 (2014) 1039
[2] D.J. Lee et al, Electrochemistry Communications, 34 (2013) 98-101
[3] J.Y. Choi et al, Advanced Funtional Materials, 23 (2013) 2108-2114

Acknowledgements

This work was supported by the IT R&D program of MKE/KEIT. [10041142, Electrolyte Additive for 200Wh/kg High LIB of High Cycle Life]
Synthesis and Understanding of Layered Li-Rich Nickel Manganese Oxides for High Energy Density Lithium-Ion Batteries
Authors: Martinet Sebastien , Boulineau Adrien , Simonin Loic , Colin Jean François , Daniel Lise , Peralta David , Feydi Pierre , Fabre Frederic , Chapuis-Rey Marlene , Patoux Sebastien 
Published: February 2020

In the search for high capacity cathode materials for Li-ion batteries, layered oxides with the general formula Li(LiXMnYMZ)O2 (M=Ni, Mn, Mg, ...) either described as xLi2MnO3 · yLiMO2 are receiving much attention. These oxides are characterised by the presence of lithium in the transition metal layers, and high Mn content, leading to high capacities up to 250mAh.g-1. However, upon cycling, they present complex structural changes that are still misunderstood.
In this context, our group worked jointly on synthesis development and understanding of the structure evolution occurring into the lithium rich layered cathode material Li1.2Mn0.61Ni0.18Mg0.01O2.
The first step was to study one material synthesized using a solid state route. 1st cycle characterization was investigated by XANES, in situ XRD and SQUID magnetic measurements. We showed that the main first-charge plateau is a twophase process where a new phase is created. This extra phase apparition was confirmed by Electron Energy Loss Spectroscopy (EELS) spectra interpretation. Therefore, Squid magnetic measurements allow a 1st cycle mechanism proposition.
Evolutions after cycling test (50 cycles) have also been investigated using advanced microscopy tools (High Resolution STEM EELS spectrum imaging). The stability of the spinel defect structure is pointed out to explain the material ageing and the electrochemical performances decrease on cycling.
Others synthesis routes were developed, especially solvothermal way enabling a better primary particles size, composition and morphology control. This synthesis route depends on many input parameters such as pH, temperature, duration… We used the methodology of the design of experiments that allows minimizing the number of experiences to optimize the synthesis and understand the effect of the main parameters of the synthesis. Higher performances and cycling behaviour have been obtained and further understanding studies are under progress to match with experimental observations.
Searching for the Best Electrolyte Composition for the C/Li2MnSiO4 Based Battery Systems
Authors: Swietoslawski Michal , Molenda Marcin , Dziembaj Roman 
Published: February 2020

Li2MnSiO4 is one of the most promising among all of polianionic cathode materials for Li-ion batteries [1-5]. Thanks to its unique composition the material is characterized by high theoretical capacity (333 mAh g-1) and potentially low production costs. On the other hand, the main disadvantage of Li2MnSiO4 is its extremely low electrical conductivity [2]. Preparation of nano-sized material and its modification by carbon coating is in this case essential to provide good electrochemical properties [1,2]. Another drawback of this material is its structural instability in charge/discharge process. There is a number of reports showing that Li2MnSiO4 cathode material undergoes amorphization in the first few charging/discharging cycles [3-5]. Degradation of crystalline structure can be explained by Jahn-Taller distortion associated with changes in lattice parameters during Mn3+ → Mn4+ transition. Another explanation may be occurrence of secondary reactions between electrolyte and delithated forms of lithium manganese silicate (LiMnSiO4 and MnSiO4). The aforementioned structural changes of the material entail variations in electrochemical properties of Li2MnSiO4.
The goal of these studies is to examine influence of different electrolyte composition on C/Li2MnSiO4stability and its electrochemical properties in the first charging/discharging cycles.
For the purpose of this studies we chose a set of electrolytes characterized by different chemical behavior toward electrode materials. The various electrolytes compositions based on LiPF6, LiClO4, LiBOB and LTFSi salts in different solvents mixtures (EC/DMC, EC/DEC, TMS/EMC) were tested with C/Li2MnSiO4 nanocomposite. Li2MnSiO4was obtained via sol-gel synthesis. Active material was carbon coated using poly-N-vinylformamide with pyromellitic acid additive as carbon precursor. Electrochemical properties of assembled cells (CR2032 housing) were studied by galvanostatic charge/discharge tests, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) methods.
This work was supported by the International PhD-studies programme at the Faculty of Chemistry Jagiellonian University within the Foundation for Polish Science MPD Programme co-financed by the EU European Regional Development Fund. The authors acknowledge a financial support from the European Institute of Innovation and Technology under the KIC InnoEnergy NewMat project.
References:
[1] M.E. Arroyo-de Dompablo, M. Armand, J.M. Tarascon, U. Amator, Electrochem Commun 81292-1298 (2006).
[2] A. Kokalj, R. Dominko, G. Mali, A. Meden, M. Gaberscek, J. Jamnik, Chem Mater 193633-3640 (2007).
[3] M. Molenda, M. Świętosławski, A. Rafalska-Łasocha, R. Dziembaj Functional Material Letters 4135-138 (2011).
[4] V. Aravindan, S. Ravi, W.S. Kim, S.Y. Lee, J Colloid Interf Sci 355472–477 (2011).
[5] M. Świętosławski, M. Molenda, K. Furczoń, R. Dziembaj, J Power Sources 244 510-514 (2013).
A Study on the Production of NMC622 Cathode Materials Using a Novel Taylor-Couette Flow Reactor Process
Authors: Kim Junghoon , Song Jung-Hoon , 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.
V2O5 Nanosheets/Reduced Graphene Oxide Nanocomposite As a High-Performance Cathode Material for Lithium-Ion Batteries
Authors: Cheng Jianli , Wang Bin 
Published: February 2020

Among the existing cathode materials, V2O5 is a promising cathode candidate because of its high energy density, abundance, easy synthesis, as well as low cost. However, due to quite low diffusion coefficient of lithium ions (10-12-10-13 cm2 s-1), irreversible phase transitions during deep discharge, and vanadium dissolution into the electrolyte, the practical use of V2O5 as a cathode material shows poor rate capability and cycling stability1,2. Incorporating the nanostructured V2O5 with high conductive materials to build a hybrid material is one of the most promising strategies to improve the electrochemical property of the V2O5 based anod3. Among these conductive materials, graphene nanosheet (GNS), with the exceptional properties of excellent electronic conductivity of 103-104 S m-1, high theoretical surface area of 2630 m2 g-1, and high mechanical ﬂexibility is much more attractive. Extensive studies of GNS-V2O5 nanocomposites have been investigated. However, it is worth noting that most of the reported nanocomposites constitute by the GNS with the zero-dimensional (0-D) nanoparticles or one-dimensional (1-D) V2O5 nanofiber/nanorod. To the best of our knowledge, the 3-D nanocomposites combining the GNS layer with 2-D V2O5 nanosheets have not been reported so far.
Herein, we demonstrate a simple solvothermal method to directly self-assemble 2-D V2O5 nanosheets on the reduced graphene oxide, forming 3-D nanocomposite (V2O5 nanosheet/RGO hierarchical nanocomposite). Briefly, vanadium oxytriisopropoxide (VO(OiPr)3) and graphene oxide (GO) were dispersed into ethyl alcohol by ultrasonicaiton to produce a V-precursor/GO dispersion. Then, the dispersion was transferred to a Teflon-lined stainless steel autoclave and heat-treated in an electric oven. The obtained composite was further annealed at 300°C in air to make V2O5 crystallized and reduce GO to RGO. The detailed preparation procedures can be found in the experimental section.
When used as a cathode material, the V2O5 nanosheets/RGO nanocomposites exhibits highly reversible capacity and good rate capability over bulk material. The V2O5 nanosheets/RGO nanocomposite anode was able to charge/discharge at high current densities of 15A g-1 (50C), with the discharge capacities of approximately 176 mA h g-1. Meanwhile, a discharge capacity of 102 mA h g-1 can be delivered after 160 cycles at 2C, showing a good cycling stability. The improved performance could be attributed to the enhanced electron transport and Li+ diffusion that result from the hierarchical nanostructure of V2O5 nanosheets/RGO nanocomposite (showing in Figure 1).
Reference:
[1] S. Q. Wang, S. R. Li, Y. Sun, X. Y. Feng, C. H. Chen, Energy & Environmental Science 2011, 4, 2854.
[2] Y. X. Tang, X. H. Rui, Y. Y. Zhang, T. M. Lim, Z. L. Dong, H. H. Hng, X. D. Chen, Q. Y. Yan, Z. Chen, Journal of Materials Chemistry A 2013, 1, 82.
[3] X. H. Rui, J. X. Zhu, D. Sim, C. Xu, Y. Zeng, H. H. Hng, T. M. Lim, Q. Y. Yan, Nanoscale 2011, 3, 4752.
Water-Based PVDF Binder for Improved Performance and Stability of Batteries
Authors: Colombo Roberta , Pieri Riccardo , Stanga Milena 
Published: February 2020

PVDF, a partially fluorinated semi-crystalline polymer, is one of the preferred choices as binder material for electrodes thanks to its stable and reliable performance in terms of longer cycle life, better power performance and higher energy density. Moreover PVDF brings advantages to the lithium battery industry in the design of the separators.
However, PVDF usually requires the use of solvent-based processing such as NMP, which is both costly and toxic.
Solvay introduces a novel fluorinated binder in aqueous dispersion with proprietary chemical modification for improved performance (in terms of adhesion and chemical resistance) and a sustainable manufacturing process.
Differently from any other PVDF-based system, this novel PVDF latex ensures continuous film of binder between active material particles. The chemical modification in PVDF ensures also improved higher and more stable adhesion in combination with flexibility (cohesion) of the final electrode.
In negative electrode, taking advantage of PVDF binder high adhesion and lower volume at equal weight compared to SBR, reduced amount of binder can be used in the formulation increasing the amount of active material (to exploit the theoretical capacity and energy density of the battery). In other hands, increased electrode cohesion and adhesion onto current collector ensures required chemical resistance and dimensional stability of electrodes in electrolyte even in stressful conditions.
Moreover, chemical affinity of PVDF with commercial polyolefin separators allows to laminate (ensuring better interface) them together. SBR does not provide such advantage, due to lower polarity leading to lack of continuous contact at interface.