bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of Cell Components on Rate and Power Capability of Li-Ion Cells
Authors: Rempel Jane , Ofer David , Dalton-Castor Sharon , Pullen Adrian , Barnett Brian , Sriramulu Suresh 
Published: February 2020

Many applications require Li-ion cells that can support high rates and/or high-power pulses. In order to effectively design such cells, it is important to understand the factors that control the rate and/or power capability of Li-ion cells.
Work done at TIAX has shown a surprising impact of the separator employed in the cell on the rate/power capability of Li-ion cells. Figure 1 shows the rate capability of a high-nickel cathode material as a function of discharge rate for three different electrode loadings. The rate capability appears independent of loading for rates less than 1 C. However, at rates higher than 2C, the rate capability appears to depend strongly on the loading. From these data it is tempting to conclude that this result is a consequence of increased ion diffusion limitation in the thicker electrode – essentially the thickness of the electrode at the loading of 27.1mg/cm2 is almost twice the thickness of the electrode at a loading of 15.6mg/cm2. However, a different conclusion emerges if these same data are plotted as a function of areal current density instead of C-rate (Figure 2). The discharge capacities appear independent of the electrode loading, but depend strongly on the areal current density. Essentially, the ionic limitations are not in the electrode, but elsewhere in the cell.
Studies at TIAX have shown that the primary ionic limitation under these conditions occurs in the separator. Data presented in Figure 3 demonstrate this effect. Essentially, by changing only the separator the discharge capacity at a current density of 16 mA/cm2(corresponding to 5 C) can be increased by a factor of four.
These combined results discussed above show that the ionic transport limitations in the separator play a major role in determining the rate capability of Li-ion cells. In this paper, we will present rate data using separators with a wide range of physical properties, and demonstrate a correlation between the rate capability and separator properties. Using data comparing the rate capability of different cathode active materials, we will discuss the implications of our findings for research aimed at understanding the power and rate capability of active materials. Finally, we will provide coin cell design guidelines for measuring the rate capabilities of active materials.
Lithium Rich Layered Material with Excellnt Rate Performance and High Efficiency
Authors: Zhan Hui , Han Zenghui 
Published: February 2020

Introduction

Lithium rich layered material has attracted much attention because of its high capacity, however, the low effciency in the 1st cycle and poor rate property is a big issue for its practical use. We adopted a (NH4)2S2O8 treatment on Li1.2Ni0.16Co0.08Mn0.56O2 material, the prodcut showed a greatly increased 1st cycle efficinecy of above 90% and a capacity as high as 200mAh. g -1at 4C rate.

Experiment

Li1.2Ni0.16Co0.08Mn0.56O2 was prepared by a rheological method. Stoichiometric amount of Li2CO3, Ni(CH3COO)2·4H2O, Co(CH3COO)2·4H2O, Mn(CH3COO)2·4H2O and oxalic acid were mixed. And then a proper amount of water was added. After stirring the mixture at 80-90 ºC for 4 h, it was dried at 120 ºC for 10 h, followed by annealing at 850 ºC for 20 h. (NH4)2S2O8 solution with different concerntration was used to treat the above Li1.2Ni0.16Co0.08Mn0.56O2 sample, the product was named as 20%-RL,30%-RL, 40%-RL, 50%-RL according the different concerntration of (NH4)2S2O8solution.
Cycling test was conducted to evaluate the cyclcing stability and rate property of the products. The samples were characterized in terms of XRD, SEM, XPS and Raman measurement.

Result and discussion

The 1st charge/discharge curves are compared in Fig.1. The pristine Li1.2Ni0.16Co0.08Mn0.56O2 shows an intial caapcity of 224.0 mAh g-1 but with a low efficiency of 79%. With the increasing of the (NH4)2S2O8 concerntration, the product shows an increased effciency and reachs 99% in the “40%-RL” sample. Additionally, the (NH4)2S2O8 treatment leads to an improvement in the cycling stability. In Fig.2, untreated Li1.2Ni0.16Co0.08Mn0.56O2 maintains 88% capacity in the 100thcycle, while the “40%-RL” sample shows capacity retention of 97% after 100 cyles.
The (NH4)2S2O8-treated samples also present greatly improved rate performance. In Fig.3, the increase of the current rate from 0.1C to 4C causes a capacity decrease from 255mAh.g-1 to 67mAh.g-1 for the pristine Li1.2Ni0.16Co0.08Mn0.56O2 sample. For the (NH4)2S2O8-treated samples, they all exhibit a much better rate property than the untreated phase. Especially for the “30%-RL” and “40%-RL” sample, they both present a capcity above 200mAh.g-1at the 4C rate.
XRD measurements prove that the (NH4)2S2O8-treatment weakens the super lattice in the Lithium rich layered material. ICP and Raman analysis furtheres reveal that the Li content in Li2MnO3 decreased after the (NH4)2S2O8-treatment, which can be the main reason of the efficiency increase in the 1st cycle.
Optimization of Full Concentration Gradient Li[NixCo0.16Mn0.84-X]O2 (x=0.64, 0.59, 0.51) Cathode Material for Lithium-Ion Batteries
Authors: Noh Hyung-Joo , Ju Jin-Wook , Lee Eung-Ju , Yoon Chong seung , Myung Seung-Taek , Sun Yang-Kook 
Published: February 2020

Lithium batteries are being developed as power sources for plug-in hybrid electric and electric vehicles, and for these applications, high energy cathodes are necessary to reduce battery size because the mounting space is significantly limited (1-2). However, these cathodes exhibit some serious problems such as capacity fade and poor thermal stability, which hinders their use in vehicle applications. In particular, oxygen evolution from the delithiated cathode can cause serious safety concerns. These limitations necessitate the development of new materials to resolve the above-mentioned difficulties. Recently, we introduced unique materials, which have a core-shell (core with gradient shell) or full concentration gradient (FCG) structure in a particle level (3). The structure is basically composed of a Ni-rich core that delivers high capacity and a Mn-rich shell that provides outstanding thermal stability. However, the Mn concentration could not be varied because of the difficulty of the rod-shaped particle synthesis.
We report the design of FCG Li[NixCo0.16Mn0.84-x]O2 (x = 0.64, 0.59, and 0.51) cathode materials with fixed Mn contents of 20, 25, and 33% in the transition metal layer. These cathode materials with concentration gradients followed the general performance trend of conventional layered materials; an increase in Ni content improved the capacity, whereas a higher amount of Mn delivered better capacity retention and thermal properties at the expense of capacity. We also report the effects of Mn concentration in terms of structural, electrochemical, and thermal characteristics of the FCG materials. As a result, we determined an optimal level of Mn concentration among the tested FCG cathodes, which maximized the discharge capacity of 188 mAh g-1 and had an excellent capacity retention of 96 % over 100 cycles operated up to 4.3 V at 25 oC, with a composition of FCG Li[Ni0.59Co0.16Mn0.25]O2.
Reference
1. J. B. Goodenough, Y. Kim, Chem. Mater.22 (2010) 587
2. V. Etacheri, R. Marom, R. Elazari, G. Salitra, D. Aurbach, Energy Environ. Sci.4 (2011) 3243
3. Y.-K. Sun, S.-T. Myung, M.-H. Kim, J. Prakash, K. Amine, J. Amer.

Chem. Soc. 127 (2005) 13411
The Influence of Solvents and Salts on the Properties of High-Voltage Cathode Materials at High Loads and High Temperatures
Authors: Kazda Tomá , Vondrák Jiri , Sedlaříková Marie , Čudek Pavel , Visintin Arnaldo 
Published: February 2020

Lithium - ion batteries play an increasingly important role in the battery industry and they have become the dominant source of energy in the recnt years, especially for portable electronic devices due to their high gravimetric energy density. The new generations of lithium – ion battery cells are based on high-voltage cathode materials. These materials are characterized by a voltage near 5 V and higher energy density than the one currently used in lithium -ion cells. This advantage could help to increase battery expansion especially in transport. Representatives of this type of cathode materials are for example LiNi0,5Mn1,5O4, LiCoPO4 and Li2CoPO4F. The advantage of these materials is also their disadvantage - high working voltage means a big ballast for the electrolytes leading to deterioration of their stability. The stability of conventional carbonate electrolytes is strongly related to the stability and properties of cathode materials in the de-lithiated state. This article examines the influence of mixtures of solvents with different combinations of lithium salts on the stability of two types of high-voltage cathode materials: LiNi0,5Mn1,5O4 and LiCr0,1Ni0,5Mn1,5O4 produced by a solid phase reaction. These materials were combined with several different electrolytes, cycled at various loads and elevated temperature. For these measurements various combinations of solvents ethylene carbonate (EC), dimethyl carbonate (DMC) and sulfolane were used. Salts LiPF6 , LiNO3 and LiTFSI were used.
Authors gratefully acknowledge financial support from the Centre for Research and Utilization of Renewable Energy under project No. CZ.1.05/2.1.00/01.0014, FEKT-S-11-7 and Company FEI.
New PVDF-Based Separator for Consumer Electronic Battery
Authors: Hamon Christine , Abusleme Julio A. , Pieri Riccardo , Rouault Helene , Mourzagh Djamel , Salomon Jérémie 
Published: February 2020

Li-ion batteries are used in most of our portable electronics by virtue of their high energy and power density. The consumer electronics market is rapidly expanding the range of applications into unconventional fields as flexible and wearable, conformable and curved devices, which require advanced lithium ion battery technologies capable of being accommodated into different shapes without constraining their form factor. Therefore the battery core has to keep its physical integrity to be capable to deliver its best performances, whatever its position.
And the battery components must be redesigned to be able to be deformed for a better integration in electronic devices. In particular the standard porous polyolefin separator does not fully match these requirements and there is always the risk that mechanical distortion can cause the leakage of liquid electrolytes.
Consequently Solvay is developing a new polymeric separator, based on thin and dense PVDF film obtained by extrusion process. The advantages of high chemical and electrochemical stability of PVDF associated with its good mechanical integrity and excellent affinity with liquid electrolyte have been coupled with the presence of a plasticizer which guarantees sufficient ionic conductivity for use in consumer electronics.
Thus in collaboration with CEA-Liten, new PVDF polymers have been studied for a better affinity with the plasticizer in order to optimize mechanical properties, ionic conductivity and performances in lithium-ion battery. Furthermore in addition to excellent flexibility, the separator shows excellent colamination properties with the electrodes, good adhesion and low interface issues.
The first tests in conformable small pouch batteries show the possibility to integrate this new separator in flexible and curved batteries.
All Solid State Lithium–Sulfur Battery Using a Glass-Type P2S5–Li2s Electrolyte
Authors: Agostini Marco , Hassoun Jusef , Yamada Takanobu , Aihara Yuichi , Scrosati Bruno 
Published: February 2020

Introduction

Lithium-sulfur battery has attracted great attention since its electrochemical process, i.e. 16Li + S8 = 8Li2S, theoretically provides a specific energy of 2500 Wh Kg-1 much larger than the 650 Wh Kg-1 of the conventional lithium battery presently offered by the market and largely used in the electronic devices. However, to realize the practical battery based on the sulfur cathode, its red-ox shuttle of polysulfide originated in the dissolution into the organic electrolyte is strongly required to prevent for improving the charge/discharge cycle ability. On the contrary, solid state sulfide electrolytes are of considerable practical concern in these days. Application of a solid-state ion conductor is one of promising candidates for avoiding the red-ox shuttle due to the dissolution of polysulfide in Li-S battery. Its applicability of Li2S-P2S5 based solid electrolyte to the sulfur cathode has been reported using Li-In alloy for the anode1). To obtain higher energy density, we adopted pure Li and verified its applicability to the all solid-state Li-S battery.

Experimental

A solid state lithium ion conductor was prepared by using high energy ball milling method. Li2S:P2S5=80:20 mol% (SE) was adopted. A coin cell, 2032 was prepared by stacking and compressing Li foil, SE, and sulfur/MCMB(50:50wt%) mixture. The loading level of net sulfur was approximately 0.9mgcm-2. Another cell configuration, a compression metal cell was also used for verifying the electrochemical performances. The electrochemical measurements were mostly performed at 80 oC. The details are given in our previous paper2).

Results and Discussion

The Li/Li2S–P2S5/S-MCMB cell was prepared and its electrochemical characteristics were evaluated by Galvanostatic charge discharge cycle at 80 °C. The average discharge potential was approximately 2.1 V and a cycling capacity of 400 mAh g−1 at a C/20 rate was observed. The cycling tests show ca.100% Coulombic efficiency and stable capacity. However, only 25% of the theoretical capacity of the sulfur electrode was obtained in this system, because of the high resistance of the solid–solid interface at the cathode side and the associated ohmic polarization during cycling. Nevertheless, the very stable capacity of 400 mAh g−1 at a working voltage of 2.1 V results in a theoretical energy density of 840 Wh kg−1, In addition, the solid cell here reported is characterized by very high safety level, since the cell is completely based on solid-state. The details of the electrochemical characteristics on anode and cathode including recent progress are given in the poster.
1) M. Nagao, A. Hayashi, M. Tatsumisago, J. Mater. Chem. 22 (2012) 10015–10020
2) M. Agostini, Y. Aihara, T. Yamada, B. Scrosati, J. Hassoun, Solid State Ionics 244 (2013) 48–51
Li Ion-Sulfur Batteries with Glyme-Lithium Salt Solvate Ionic Liquid Electrolytes
Authors: Mandai Toshihiko , Yamazaki Azusa , Ueno Kazuhide , Zhang Ce , Yoshida Kazuki , Moon HeeJoon , Dokko Kaoru , Watanabe Masayoshi 
Published: February 2020

We have reported that equimolar mixtures of certain Li salts and glymes (triglyme (G3) and tetraglyme (G4)) form molten complexes at ambient temperature, and behave like typical ionic liquids (ILs).1,2 In the mixtures, ligand glyme molecules strongly coordinate (or solvate) to Li+ ions to form complex cations, hence, this family is classified as “solvate” ILs. Because complexation of appropriate Li salts with appropriate glymes allows realizing ILs involving Li+ ions as single cationic species, lithium solvate ILs possess high Li+ ion conductivity and transference number. In addition, the dissolution of lithium polysulfides (Li2S
m
), the discharge products of elemental sulfur, was suppressed in certain solvate ILs due to their extremely low coordinating nature. Owing to these remarkable properties, they are fascinating electrolytes for Li-sulfur batteries.3,4

Recently, we found that solvate IL electrolyte allows successful charge-discharge of graphite electrode. These results inspire us to develop low-cost and safe batteries without Li metal anode. In this study, the battery performance of the graphite-sulfur full cells with the solvate IL electrolytes was evaluated employing a lithiated graphite (LiC6) anode or a lithiated sulfur (lithium sulfide, Li2S) cathode as a lithium source. A LiC6 anode and a Li2S cathode were prepared by chemical and electrochemical methods. Using these electrodes, two kinds of full cells in both charge and discharge states were fabricated.
Reversible charge-discharge of both full cells can be performed at 60 ºC, however, the capacities decrease as repeating cycles and the coulombic efficiency for these cells is substantially low compared to our previous results. This is because relatively high operation temperature facilitate dissolution of elemental sulfur and/or Li2S
m
, leading to loss of active materials and undesired side-reactions. To overcome these problems, solvate IL electrolytes were diluted by an appropriate solvent with low donor ability. As a result, a stable cycle operation with a discharge capacity of 700–800 mA h g−1 and a coulombic efficiency of 90–95 % at 30 ºC was achieved over 100 cycles (Figure 1), irrespective of starting charge-discharge states.
Multi-Methodology Modeling and Design of Lithium-Air Cells with Aqueous Electrolyte
Authors: Grübl Daniel , Danner Timo , Kupper Christian , Schulz Volker P , Latz Arnulf , Bessler Wolfgang G. 
Published: February 2020

Metal-air batteries are being investigated as alternative to state-of-the-art lithium-ion batteries for mobile and stationary applications due to their higher specific energy and potentially lower cost. Modeling and simulation techniques allow a better understanding and improvement of the complex mechanisms and properties of metal-air batteries. Here we present combined modeling and experimental results on a lithium-air (Li/O2) battery with aqueous alkaline (LiOH) electrolyte using three different modeling methodologies, (i) Lattice-Boltzmann simulations on the porous electrode scale, (ii) multi-physics continuum modeling on the single-cell scale and (iii) system simulation of a Li/O2-operated electric vehicle.
Lattice-Boltzmann simulations on experimentally reconstructed Ag-based gas diffusion electrodes (GDE) are performed in order to derive multi-phase transport parameters, in particular, saturation/pressure relationships and effective diffusion coefficients. The computational domain of the 1D continuum model consists of the gas-diffusion electrode as cathode, a porous separator, and a lithium metal anode. The model includes a detailed description of the multi-step electrochemistry including dissolution of O2into the liquid electrolyte, oxygen reduction to hydroxyl ions, and nucleation and growth of the solid reaction product LiOH [1]. The model is validated with experimental half-cell measurements over a wide range of conditions. The multi-physics model is integrated into a system simulation of a battery electric vehicle, including electric engine and regenerative braking. The model is used to simulate driving cycles (Fig. 1), which allow to quantify practical energy and power densities and to investigate the potential of lithium-air technology as next-generation battery for electromobility.
As key result, the alkaline lithium-air battery offers the interesting capability of high-power cycling using only liquid-phase dissolved intermediates (O2 + 4e– + 2 H2O ⇄ 4 OH–) coupled to high-energy content due to solid product formation (Li+ + OH– + H2O ⇄ LiOH·H2O). This dual functionality can be exploited for the driving cycle using model-based cell design.
[1] B. Horstmann, T. Danner, and W. G. Bessler, “Precipitation in aqueous lithium-oxygen batteries: a model-based analysis,” Energy & Environmental Science 6, 1299–1314 (2013).
First Principles Investigations of Reactions Mechanisms of LixMO4 (M=Fe, Mn, Ni, Co) Electrodes/Electrocatalysts for Hybrid Li-Ion/Li-O2 Cells
Authors: Kinaci Alper , Trahey Lynn , Thackeray Michael M. , Kirklin Scott J. , Wolverton Chris , Chan Maria K. Y. 
Published: February 2020

We recently proposed a vision for high energy, ‘all-in-one’ electrode/electrocatalyst materials for hybrid Li-ion/Li-O2 cells [1]. Electrochemical experiments with Li5FeO4, which has a defect antifluorite-type structure, have demonstrated a substantially smaller voltage polarization during charge and discharge and hence a higher energy efficiency compared to standard reactions between lithium and oxygen to form Li2O2 [2]. Other materials in this class include Li6MO4 (M=Mn, Ni, Co) that offer a theoretical capacity of ~1000 mAh/g at ~3 V. The mechanisms by which these materials delithiate and lose oxygen, however, is not well understood. The results of first principles density functional theory (DFT) calculations to establish the thermodynamic conditions for the extraction of Li/Li+O from Li5FeO4 and Li6MO4 compounds will be presented. A step-by-step, history-dependent, removal process is followed; the stability of Li and Li+O deficient samples is investigated on the basis of the extraction reaction energies. Various stages of Li/Li+O removal are identified. Structural changes and electronic structure evolution, as well as computed characterizations of the reactions will also be reported.
[1] M. M. Thackeray, M. K. Y. Chan, L. Trahey, S. Kirklin, and C. Wolverton, Journal of Physical Chemistry Letters, 4, 3607 (2013).
[2] L. Trahey, C. S. Johnson, J. T. Vaughey, S.-H. Kang, L. J. Hardwick, S. A. Freunberger, P. G. Bruce, M. M. Thackeray, Electrochemical and Solid-State Letters, 14, A64 (2011).
The Effect of Pore Size Controlled Carbon for Lithium Oxygen Batteries
Authors: Kwak Won Jin , Park Jin-Bum , Sun Yang-Kook 
Published: February 2020

The lithium-oxygen battery has been attracting great attention around the world due to its extremely high energy density (i.e., 1-2 kWh kg-1), which could well satisfy the ever increased energy requirement from electronic devices, especially the electric vehicle and plug-in hybrid electric vehicle.1-3

This exceptional energy potentiality has trigged the worldwide interest in this super energy storage system. However, despite large R&D efforts devoted to its implementation, several issues, associated with both electrodes and electrolytes, have so far limited the performance of the lithium oxygen battery due to few discharge-charge cycles and low rate capability.4, 5

Many materials are used for cathode in lithium oxygen battery. Among them, carbon is the mostly used material because of the advantage in the way that amount and cost, although it has been talked making by-product like Li2CO3. (Some paper told that not only carbon but also electrolyte makes the problem in lithium oxygen battery system)
In this study, we show that Ordered mesoporous carbon (OMC) with highly ordered pore channels which was applied as an oxygen-side electrode for a lithium-oxygen battery.
To evaluate the effect of the pore channel size on battery performance, OMCs possessing two different pore sizes (6 and 17 nm) were employed. When cycled at a current density of 200 mA g-1carbon, the OMC electrodes reduced polarization in the oxygen evolution reaction by 0.1 V compared to those consisting of conventional super P carbon electrode. X-ray diffraction and transmission electron microscopy of the discharged oxygen electrodes provided evidence for the formation of amorphous Li2O2, a product of the oxygen reduction reaction, inside the OMC pores rather than on the electrode surface as in the case of the super P electrode. The OMC electrodes were also effective at high current densities (500 mA g-1carbon and 1000 mA g-1carbon).
References
[1] K.M. Abraham, Journal of The Electrochemical Society, 143 (1996) 1.
[2] G. Girishkumar, B. McCloskey, A.C. Luntz, S. Swanson, and W. Wilcke, J Phys Chem Lett, 1 (2010) 2193-2203.
[3] B. Scrosati, J. Hassoun, and Y.K. Sun, Energ Environ Sci, 4 (2011) 3287-3295.
[4] S.A. Freunberger, Y. Chen, Z. Peng, J.M. Griffin, L. J. Hardwick, F. Bard, P. Novak, P. G. Bruce, J. Am. Chem. Soc. 133 (2011) 8040-8047.
[5] G.R. Mettam, L.B. Adams in: B.S. Jones, R.Z. Smith (Eds.), Introduction to the Electronic Age, E-Publishing Inc., New York, (2009), pp. 281–304.