bluuebunny/crossref_metadata_2025_split huggingface dataset:
CFD Analysis of Aggregation and Breakage of Li-Ion Precursor in Taylor-Reactor
Authors: Lee Seung-Hun , Jeon Dong Hyup , Song Jung-Hoon 
Published: February 2020

In this work, aggregation and breakage of Li-ion precursor in Taylor-reactor are studied for various simulation condition, i.e., agitation rate, particle property, and reactor direction. The mean particle size and distribution is important to electrochemical performance of cathode materials. The population balance equation (PBE) is solved for coupling between particle interaction and fluid dynamic. The quadrature method of moments (QMOM) is implemented in a commercial computational fluid dynamics (CFD) code. Sum of three aggregation kernels, such as turbulent, Brownian, and Stokes aggregation, is considered for the calculation. [1] Breakage kernel is a combination of power-law kernel and various daughter distribution functions. Collision efficiency is assumed to be equal and the precursor is considered as spherical particle. Three-dimensional analysis is implemented and the simulation results are compared with experimental data.
[1] L. Claudotte, N. Rimbert, P. Gardin, M. Simonnet, J. Lehmann, and B. Oesterle, AIChE J., Vol.56, No.9, pp. 2347-2355 (2010)
High Rate, Stable Porous Silicon Deposition By Thermal Plasma Technology
Authors: Bosch Roel C.M. , Borsa Dana M. , Mulder Fokko M. 
Published: February 2020

Meyer Burger (Netherlands) B.V. is a manufacturer of industrial high speed deposition equipment. Our thermal plasma deposition technology has been used since two years to produce thick silicon coatings on metal foils for battery applications. In several collaborations we have demonstrated high quality coatings at high deposition speed (>10 micron / min) on 3D structured current collectors, where coating stability (cycle life) is obtained by growth parameters and porosity of the amorphous coatings. In one example we have used this growth process to deposit 2.1 mg/cm2 silicon on a thin conductive foil which resulted in a stable capacity level of around 1000mAh/g after 100 cycles (testing ongoing at Delft University of Technology).
The presentation will show more details on the deposition technology, growth mechanism and the properties of the thick stable silicon coatings. The economics of volume production (€ / kWh) with our 2-side R2R coating equipment for 100% silicon based anodes will also be highlighted and compared to nowadays slurry-based coating technologies.

Figure 1
Enhanced Performance of Different Carbon Coated Nano-LiFePO4/C Composites for Lithium Battery By Vacuum Thermal Decomposition
Authors: Huang Xiao-peng , Yao Yao-chun , Liang Feng , Du Yuan-chao , Dai Yong-nian 
Published: February 2020

Nano-LiFePO4/C composite cathode materials were synthesized by vacuum thermal decomposition method, using sucrose, polyvinyl alcohol (PVA) and citric acid (CA) as different carbon sources. The samples had systematically been investigated with X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Raman spectroscopy, element analysis, electrochemical impedance spectroscopy and charge/discharge measurements. Under vacuum sintering condition, the thermal decomposition rate of organic carbon source was significant accelerated and active carbon were formed to coat LiFePO4 particle. The obtained LiFePO4/C sample showed highly crystalized olivine-type structure and spherical-like particles of 100-300 nm, delivering an enhancement of rates capacity than traditional argon sintered LiFePO4/C material. Besides, the effect of different carbon sources (sucrose, PVA and CA) on the properties of LiFePO4/C composite was paid special attention. SEM and TEM analysis showed that all the LiFePO4/C samples had nano size particle but differ in carbon morphology and layer thickness. After vacuum thermal decomposition, the residual carbon content decomposed by sucrose, PVA and CA was about 2.5%, 3.1% and 1.8%, respectively. EIS spectra indicated that the sucrose coated LiFePO4/C electrode had the lowest charge transfer resistance (Rct=50 Ω) and highest lithium diffusion coefficient. As a consequence, the sucrose coated LiFePO4/C synthesized under vacuum decomposition exhibited the best discharge capacity of 155.1, 153.7, 148.6, 140.3, 123.9 and 80.1 mA·h·g-1 at 0.2 C, 0.5 C, 1 C, 2 C, 5 C and 10 C, respectively. The results indicated that organic carbon sources can be prior carbonized and the performance of LiFePO4/C composite can be further improved by vacuum thermal decomposition.
Facile Redox Synthesis of Layered LiNi1/3Co1/3Mn1/3O2 for Rechargeable Li-Ion Batteries
Authors: Baboo Joseph Paul , Gim Jihyeon , Song Jinju , Kim Sungjin , Jo Jeonggeun , Pham Duong Tung , Kim Seokhun , Yang Juhyun , Kim Jaekook 
Published: February 2020

The increasing demand for energy storage devices has motivated the need to find environmentally friendly, high energy density, and cost-effective materials for energy storage and suitable synthesis techniques. In this work, we report a simple and cost-effective chemical route, in which intermediate Ni1/3Co1/3Mn1/3(OH)2 product was primarily prepared using a simple redox synthesis technique at ambient temperature. Lithiation reactions were then performed at higher temperatures to develop the final layered Lix(Ni1/3Co1/3Mn1/3)O2 structure (where x= 1.0 and 1.05). The lithium content was varied in order to analyze the effect of excess lithiation on the structural and electrochemical properties of the layered-type Li(Ni1/3Co1/3Mn1/3)O2 cathode. The XRD studies clearly confirmed the formation of layered-type structures corresponding to hexagonal α-NaFeO2 (space group R-3m). The ICP studies confirmed the stoichiometric chemical composition (Li(Ni0.32Co0.33Mn0.31)O2) of the prepared samples. FE-SEM images revealed that the particle growth occurred when the particles were heated at elevated temperatures of 950°C, and the average particle diameter was around a few micrometers. The electrochemical tests performed versus lithium indicated that competitive specific capacity values were registered for all the prepared cathodes and the capacity retention was impressive on repeated charge/discharge cycling within the potential range of 3.0 – 4.3 V and a current density of 14 mA/g. In particular, the Li(Ni0.32Co0.33Mn0.31)O2 sample demonstrated the highest capacity retention value (~ 99%) after 50 cycles and better rate performances of 104, 91, 76, and 67 mAh/g at higher current densities of 229, 457, 914, and 1429 mA/g respectively.
On the Versatility of Melt-Synthesis of LiFePO4 cathode Material
Authors: Talebi-Esfandarani Majid , Rousselot Steeve , Jin Liling , Bibienne Thomas , Gauthier Michel , Chartrand Patrice , Sauriol Pierre , Seifitokaldani Ali , Liang Guoxian , Dollé Mickael 
Published: February 2020

LiFePO4 (LFP) has attracted much attention as a promising candidate for cathode materials in new generation of Li-ion batteries due to its good thermal stability, being environmentally friendly and abundance in nature. Many synthetic routes, such as solid state, sol-gel, hydrothermal, co-precipitation, and microwave preparations, have been used for preparing LFP. In 2003, Gauthier et al. advanced the concept of melt synthesis. The process operating above 1000°C in the liquid phase, benefits from fast reaction kinetics and the thermodynamic stability of LiFePO4 in a reducing atmosphere. This approach allows the use of a wide range of simple raw materials as well as a possible purification strategy in the melt or upon solidification, potentially enabling for usage of less pure non-expensive raw materials.
Fundamental aspects will be addressed as this work is only feasible with a good understanding of the thermodynamics of the Li-Fe-P-O system. A model has been developed and it is supported by our experimental data. On this basis, recent experimental observations and progress on raw material selection and systems will be then reported. Melt-synthesis conditions and the latest result in controlling the purification of LiFePO4 from major phase impurities will also be covered. All these considerations allow the selection of the best conditions to prepare a high purity LiFePO4 by melt-process.
This work is part of an Automotive Partnership of Canada supported program to develop and pilot the molten-synthesis process to make high purity C-LiFePO4 with excellent electrochemical properties for using as a cathode material in Li-ion batteries for EVs and PHEVs application.
A Risk Assessment Methodology to Prioritise Risks in Large, Stationary Li-Ion Battery Systems
Authors: Mulder Grietus , Trad Khiem 
Published: February 2020

Performing a risk analysis is the basis in all engineered products. No specific methodology exists for stationary batteries. Indications on the needed risk assessment may be derived from standards that cover large stationary Li-ion battery storage systems in their scope [1]. However, they hardly go further than referring to the general risk assessment techniques with as examples Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). Despite this lack of specific guidance, a risk assessment for large battery systems has their uniqueness due to their structure. There are many levels between battery cells and the complete system. Moreover, a huge number of cells are used that must be correctly dealt with in the assessment. In the scientific literature only a few papers are dedicated to risk assessment on batteries.
This contribution sets up a complete framework of methodologies and protocols for safety testing of stationary Li-ion batteries for large-scale grid-connected applications. The risk assessment is based on the well-known Failure Mode Effects Analysis (FMEA) method. In a first step, a generic hierarchical system diagram of a stationary battery is developed to be used as the system under study in the FMEA. To improve the completeness and the objectivity of the analysis, improvements to the FMEA methodology are proposed and used. The main goal of these improvements is to limit the dependency on expert judgement and inspiration and to improve the prioritization of risks without adding unnecessary complexity. A core issue is that the method of calculating the Risk Priority Number (RPN) is not sufficient fo large battery systems. This problem was also detected by [2]. The RPN does not take suitable care of the numbers of cells, modules, etc. and has no aggregation per level. Risks that are mitigated on several system levels have to be aggregated in an advanced RPN methodology. This leads to a thorough risk assessment, in which it is easy and meaningful to select the most prominent project risks.
This contribution is an outcome of the European FP7 project Stallion. The project has set up safety tests beyond state of the art for stationary Li-ion battery systems. It also resulted in a handbook on battery system safety for the broad audience [3].
[1] Survey on standards for batteries and system integration with them. VITO, 2015. [Online] batterystandards.vito.be.
[2] Analysis of Battery Safety and Hazards’ Risk Mitigation. Ashtiani, C.N. 2008, ECS Transactions, Vol. 11, pp. 1-11 .
[3] STALLION Handbook on safety assessments for large-scale, stationary, grid-connected Li-ion energy storage systems, DNV GL, Arnhem 2015. [Online] stallion-project.eu

Figure 1
Safe Discharge of Damaged Li-Ion Batteries with Redox-Shuttle Additives
Authors: Wachtler Mario , Emmermacher Brita , Wohlfahrt-Mehrens Margret , Döring Harry 
Published: February 2020

Due to continuous research and development efforts, the intrinsic safety of Li-ion batteries (LIBs) has increased significantly over the last years. A critical issue to resolve remains the question what to do with damaged LIBs in the charged state. Batteries can contain protection mechanisms, the activation of which may result in situations where the battery cannot be electrically discharged any longer.
This contribution presents a safe way of discharging batteries at a cell level using water, aqueous salt solutions, or organic solutions of redox-shuttle additives as discharge agents. The discharge solutions can be added to the cell from the outside when discharge is required, or, in case they are already contained in the cell, they can be activated by adequate technical trigger mechanisms.
A number of examples of compounds is shown and compared for 20 Ah prismatic Li-ion cells. Typical discharge times are in the range of 30 to 60 hours (shorter times are expected for higher concentrations of the discharge agents than tested here). The end-of-discharge voltage is typically between 0 and 1 V, depending on the respective discharge agent. Discharge with water and aqueous solutions is the cheapest way of discharge, but since it is accompanied by gas evolution, it may cause secondary risks via the evolved gas. The organic solutions of redox-shuttle additives enable a complete discharge without any gas evolution, and are thus the safer option (cf. Figure: Evolution of cell voltage after addition of redox-shuttle additives). During discharge the chemical energy contained in the charged cell is converted into thermal energy. For the timescale of the given experiment, however, no noticeable heating of the cell was observed (with the temperature changes remaining < 3 °C, which was within the natural variation of the ambient temperature).
The underlying discharge reaction mechanisms are explained and requirements and limitations for the discharge agents are discussed.
Acknowledgement: Financial support of parts of this work from the German Association of the Automotive Industry (VDA) is gratefully acknowledged.

Figure 1
Correlation Between Solvation Structure and Ion-Conductive Properties of Highly-Concentrated Poly(ethylene carbonate)-Based Electrolytes
Authors: Kimura Kento , Tominaga Yoichi 
Published: February 2020

Ion-conductive solid polymer electrolytes (SPEs) are of great interest as key materials to realizing safe and flexible rechargeable batteries, particularly Li batteries. Since the discovery of ionic conductions in poly(ethylene oxide) (PEO)/metal salt complexes, numerous efforts have been made to improve their electrochemical properties. However, it is difficult to increase Li-ion conductivity that is the product of overall conductivity and Li transference number (t
+). This drawback mainly arises from excessively tight complex structures between polar polymers and Li ion.
To overcome the drawback and create all-solid-state batteries based on SPEs, we specifically focus on poly(alkylene carbonate)s derived from CO2/epoxide copolymerization as SPE polymer hosts [1,2]. Consequently, we have found an unusual ion-conductive behavior of poly(ethylene carbonate) (PEC)-based electrolyte, including high ionic conductivity of highly-concentrated electrolytes and extremely high t
+, which in some cases is above 0.8 [3,4]. In this PEC-based electrolyte system, ionic conductivity continues to increase with increasing salt concentration, which is a behavior scarcely shown in conventional electrolyte systems. In addition, we have already confirmed operations of prototype Li/LiFePO4 cells based on PEC-based electrolytes combined with plasticizing and reinforcing additives [5,6].
In this context, we considered that elucidation of salt solvation structure is a key to better understanding the origin of the particular ion-conductive behavior, and improving the performance further. In the present study, we adopted spectroscopic studies including FT-IR, Raman spectroscopy, and solid-state 7Li magic angle spinning (MAS) NMR for PEC/lithium bis(fluorosulfonyl)imide (LiFSI) electrolytes with varying concentration. The FT-IR and Raman spectroscopy indicate that most FSI ions interact with more than one Li ion at high concentration region, which is referred to as aggregates, while C=O groups dissociates the salt. The 7Li MAS NMR suggested that a relatively weak contact between Li ions and FSI ions withdraws Li ions from a strong interaction with C=O groups. We conclude that this moderate complex structure, where C=O groups allows the highly concentrated ions to remain amorphous and mobile, leads to reasonable conductivity with extremely high t
+. We believe that this finding will provide a new insight for developing SPEs having both high conductivity and high t
+ simultaneously.

References:

[1] Y. Tominaga, T. Shimomura, M. Nakamura, Polymer, 51, 4295 (2010).
[2] M. Nakamura, Y. Tominaga, Electrochim. Acta, 57, 36 (2011).
[3] Y. Tominaga, V. Nanthana, D. Tohyama, Polymer J., 44, 1155 (2012).
[4] Y. Tominaga, K. Yamazaki, Chem. Commun., 50, 648 (2014).
[5] K. Kimura, J. Hassoun, S. Panero, B. Scrosati, Y. Tominaga, Ionics, 21, 895 (2015).
[6] K. Kimura, H. Matsumoto, J. Hassoun, S. Panero, B. Scrosati, Y. Tominaga, Electrochim. Acta, 175, 134 (2015).
Solvent Effect on the Kinetics of Lithium-Ion Intercalation Reaction
Authors: Nikitina Victoria A. , Vassiliev Sergey Yu. , Levin Eduard E. 
Published: February 2020

In spite of the great number of commercialized lithium-ion intercalating systems, the intrinsic ion-transfer kinetics of the intercalation reaction is still poorly understood. The process of Li-ion intercalation comprises several stages: i) diffusion of Li ion in solution; ii) partial or complete desolvation of Li+ at the interface; iii) diffusion of the ion through cathodic or anodic SEI at the electrode surface; iv) insertion of the Li ion into the lattice of the material, which is accompanied by the transition metal ion oxidation/reduction. Under these conditions, a pronounced solvent effect on the kinetics of the process is expected, as solvent determines both the structure of the interface (SEI composition) and the desolvation energy, which contributes to the activation barrier. Construction of a self-consistent kinetic model requires careful experimental examination of all of these stages and determination of the limiting stage of the process.
In this work we focus on the solvent effect on the kinetics of lithium ion intercalation into model electrodes (LiCoO2, LiMn2O4, V2O5, etc.), as these systems are characterized by different redox potentials and, correspondingly, by different SEI compositions. We report the results of the electrochemical measurements for the model electrode materials in carbonate-based electrolytes (e.g. commercial electrolyte ethylene carbonate/dimethyl carbonate), protic solvents (water, ethylene glycol) and aprotic solvents (dimethyl sulfoxide, acetonitrile). For these groups of solvents we report the results of cyclic voltammetry numerical modeling, which allows for the determination of the intrinsic kinetic parameters of the intercalation reaction1 (diffusion coefficient, rate constant and the parameters of the intercalation isotherm). To construct an accurate kinetic model of the intercalation process the real particle size distribution, as determined from scanning electron microscopy data, is taken into account.
The observed tendencies in the rate constant values are compared with the results of quantum chemistry calculations on the DFT level of theory of the desolvation energies for the lithium ion in the solvents under study. The calculations were carried out using “cluster-continuum” approach, which allows separating the electrostatic and the non-electrostatic (specific) contributions to the overall desolvation barrier. The combination of the electrochemical experimental data with the results of molecular modeling allowed us to draw conclusions on the solvent effect on the intercalation reaction kinetics and the contribution of the lithium ion desolvation energy to the overall activation barrier.

S. Yu. Vassiliev, E. E. Levin, V. A. Nikitina. Kinetic analysis of lithium intercalating systems: cyclic voltammetry. Electrochim. Acta, doi:10.1016/j.electacta.2015.12.172.
Solid State Electrolytes for Next-Generation Lithium Ion Batteries
Authors: Narayanan Sumaletha , Thangadurai Venkataraman 
Published: February 2020

Lithium ion batteries achieve much attention because of their wide applications ranging from portable electronics to transportation and grid storage. The next-generation lithium ion batteries require a highly conducting solid electrolyte which ensures safe operation. Garnet-type oxides with nominal chemical formula, Li5La3Ta2O12 are promising Li+ conductors which show high ionic conductivity, low electronic conductivity and electrochemical stability.1 It is important to understand the fundamental electrical transport mechanism of these garnet-type solid-state Li+ conductors with respect to change in temperature and lithium content in the structure. Li+ stuffing into Li5La3Ta2O12 have proven to improve the ionic conductivity of garnet-type oxides.2 The present study reports highly conducting lithium-stuffed Li5+2xLa3Ta2-xYxO12 (0.05 ≤ x ≤ 0.75) electrolytes.3 Effect of Y3+ and Li+ doping in Li5La3Ta2O12 on the structural, morphological and electrical properties are studied in this work. Detailed analysis of crystal structure, and electrical and dielectric properties are also performed, in order to investigate the Li+ migration pathways in the crystal structure, using different techniques such as powder X-ray diffraction, solid state 7Li MAS NMR, and electrochemical impedance spectroscopy.3-4 The x = 0.50 and 0.75 members in the series of Li5+2xLa3Ta2-xYxO12 have exhibited highest conductivity of ~ 10-4 Scm-1 at 23 ºC. In addition, their stability in aqueous LiCl solution make them suitable candidate as protective layers for lithium electrodes in lithium-air batteries.3

References

1.Thangadurai, V.; Kaack, H.; Weppner, W. J. F. J. Am. Ceram. Soc.
2003, 86, 437-440.
2. Thangadurai, V.; Narayanan, S., Pinzaru, D. Chem. Soc. Rev.
2014,43, 4714-4727.
3. Narayanan, S.; Ramezanipour, F.; Thangadurai, V. Inorg. Chem.
2015,
54(14), 6968-6977.
4. Baral, A. K.; Narayanan, S.; Ramezanipour, F.; Thangadurai, V. Phys. Chem. Chem. Phys.
2014, 16, 11356-11365.
Enhanced Physical and Electrochemical Properties of LLBTZO Garnet Structures for Energy Storage Applications
Authors: Farooq Umer , Samson Alfred , Pilapil Brandy , Ganjeh Anzabi Pejman , Trifkovic Milana , Thangadurai Venkataraman , Roberts E.P.L. 
Published: February 2020

In recent years, an intensive research has been conducted to introduce the solid-state electrolytes for the future Li-ion batteries [1-2]. In this work we prepared a ceramic electrolyte Li6.5 La2.5 Ba0.5 Nb Zr O12(LLBNZO) and sintered pellets of as-prepared material at elevated temperature ranging from 1050 to 1200 0C. The objective of this research was to observe the effect of temperature on porosity, density and transport properties of materials. Preliminary results suggest that the material sintered at higher temperature could show enhanced performance in terms of fast ionic transport. This enhancement in performance can be attributed to low porosity of materials which is result of high temperature sintering.
References:
1- V. Thangadurai, D. Pinzaru, S. Narayanan, and A. K. Baral, "Fast Solid-State Li Ion Conducting Garnet-Type Structure Metal Oxides for Energy Storage," J. Phys. Chem. Lett. 6, 292−299 (2015).
2- J. Schwenzel, V. Thangadurai and W. Weppner , 'Developments of High-Voltage All-Solid-State Thin-Film Lithium Ion Batteries,' J. Power Sources 154, 232-238 (2006).