bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Experimental Observation of the Interfacial Instability of the Fast Ionic Conductor Li10GeP2S12 at the Lithium Metal Anode
Authors: Wenzel Sebastian , Zeier Wolfgang G. , Janek Jürgen 
Published: February 2020

High capacity and low potential anode materials like lithium metal are preferred for high energy densities in all solid-state batteries. Due to the highly reducing potential of lithium metal, the electrochemical and thermodynamic stability of a solid ion conductor at the interface plays a crucial role for the performance of all solid-state batteries.
When a solid electrolyte is in contact with lithium metal, three different types of interfaces may occur:1 (I) A stable interface may form with electrolytes that are thermodynamically stable against Li contact. (II) A reaction occurs and a mixed ionic-electronic conducting (MCI) new interphase forms,2 which rapidly growths due to the electronic percolation pathways. (III) A reaction occurs and a solid electrolyte interphase (SEI) forms,3 which only conducts ions. While (I) may be preferred and (II) is exclusively detrimental, due to a proceeding reaction front, the impact of (III) on the battery performance depends on the type of forming SEI.
Here we will shortly introduce the types of possible interphases/interfaces and discuss the expected effects on the overall resistance and performance of an all-solid-state battery. Using time-resolved impedance spectroscopy and time-resolved cyclic voltammetry we introduce a guideline to characterize solid electrolytes for their stability against metal interfaces. The solid electrolyte Li10GeP2S12 will be shown as an example of an instability,4 as has been theoretically predicted.5,6 SEI formation occurs, affecting the overall cell resistance detrimentally.
Using a novel in situ X-ray photoelectron technique we study the resulting interphase formation when Li10GeP2S12 is in contact with Li. Using the observed chemical species, in combination with time-resolved electrochemical measurements, we suggest a reaction mechanism for the interphase formation as well as provide an understanding of the growth kinetics.

1Wenzel S., Leichtweiss T., Krüger D., Sann J., Janek J. Solid State Ion.
2015, 278, 98-105

2Hartmann P., Leichtweiss T., Busche M., Schneider M., Reich M., Sann J., Adelhelm P., Janek J. J. Phys.
Chem. C
2013, 117, 21064-21074

3 Wenzel S., Weber D., Leichtweiss T., Busche M., Sann J., Janek J. Solid State Ion.
2016, 286, 24-33

4Wenzel S., Randau S., Leichtweiss T., Weber D., Sann J., Zeier W.G., Janek J. submitted

5Zhu Y., He X., Mo Y. ACS Appl. Mater. Int.
2015, 7, 23685-23693

6Zhu Y., He X., Mo Y. J. Mater. Chem A
2016 DOI: 10.1039/C5TA08574H.
Synthesis and Characterization of Tin Oxide By Atomic Layer Deposition for Solid-State Batteries
Authors: Novikov Pavel Alexandrovich , Maximov Maxim Yurievich , Popovich Anatoliy Anatolevich , Nazarov Denis Vasilievich , Silin Alexey Olegovich , Rumyantsev Alexander Mikhaylovich , Zhang Yongguang 
Published: February 2020

The SnO2 material has been considered as a promising lithium-ion battery anode candidate, and recently, the importance has been increased due to its high performance in sodium-ion batteries. Tin oxide (SnO2) has been studied as a promising alternative to the commercially used graphite anode material because of its much higher theoretical specific capacity 1491 mAh/g [1, 2].
Synthesis of tin oxide (IV) thin films was carried out in Picosun R-150 ALD reactor. Synthesis temperature of the process varied from 2500C to 3500C. As a source of tin was used Russian-made tetraethyltin (TET - Sn(C2H5)4, CAS № 597-64-8), purity 99.999%. Inductively coupled remote oxygen plasma and ozone was used as oxygen sources.
Thickness of thin films was measured using spectroscopic ellipsometry UVISEL 2 UV-Vis-NIR, and corresponded 75-80 nm. Surface morphology were obtained by scanning electron microscope Mira Tescan. Valence state of tin was studied by X-ray photoelectron spectroscopy (XPS). Electrochemical study of obtained thin-film electrodes was also carried out. The voltage of cycling was ranged from 0.01 V to 0.8 V. Current density was 25 µA/cm2. During cycling tests was shown that tin oxide has a stable discharge capacity about 900 mAh/g during 500 charge/discharge cycles, with efficiency about 99,5 %, fig.1. Capacity fluctuations likely to be associated with changes in ambient temperature.
Financial support was made by Ministry of Education and Science of Russian Federation. Unique identifier of the project is RFMEFI57814X0096.
[1] Jiajun Chen Materials 6 (2013), 156-183
[2] S.-Y. Lee et al. Nano Energy 19 (2016), 234–245

Figure 1
Deciphering the Structure of the Magnesium Aluminum Chloride Electrolyte in Bulk and Near the Anode Electrode
Authors: Canepa Pieremanuele , Gautam Gopalakrishnan Sai , Malik Rahul , Ceder Gerbrand 
Published: February 2020

Electrical energy storage is a key technology for a clean energy economy, but currently requires significant improvement in energy density beyond the capabilities of traditional Li-ion batteries. Mg-ion batteries are an exciting alternative in terms of the amount of energy that can be delivered, safety, manufacturing and disposal costs, with limited environmental impact. The electrochemical functions of the Mg-ion battery rely on the choice of the electrolyte, which is limited by the distinct chemistry of Mg. To date, very few electrolytes can reversibly plate and strip Mg [1,2]. The magnesium aluminum chloride complex (MACC) electrolyte can reversibly plate and strip Mg with significantly higher voltage (3.1 V) as compared to other electrolytes, but there is a pressing need to address critical questions about the structural evolution of this electrolyte during electrochemical cycling [3]. While it is well established that Mg can be deposited reversibly from complex ethereal solutions of Mg-Al chloride complex reagents, the stripping/deposition mechanism at the anode is still debated [2,3]. In this poster we present a detailed atomistic DFT study of the electrolyte in bulk and when in contact with Mg-anode surfaces. These models are essential to clarify the structure of the electrolyte under various environmental conditions as well as to provide insight on the electron-transfer mechanism occurring at the electrode/solvent interface [4,5].
[1] D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, and E. Levi, Nature
407, 724–727 (2002).
[2] N. Pour, Y. Gofer, D. T Major, and D. Aurbach, J. Am. Chem. Soc.
133, 6270–6278 (2011).
[3] R. E. Doe, R. Han, J. Hwang, A. J. Gmitter, I. Shterenberg, H. D. Yoo, N. Pour, and D. Aurbach, Chem. Commun.
50, 243–245 (2014).
[4] P. Canepa, G. S. Gautam, R. Malik, S. Jayraman, Z. Rong, K. R. Zavadil, K. Persson, G. Ceder, Chem. Mater.
27 (9), 3317–3325 (2015).

[5] P. Canepa, S. Jayaram, L. Cheng, N. N. Rajput, W. D. Richards, S. G. Gautam, L. A. Curtiss, K. A. Persson and G. Ceder, Energy Environ. Sci.

8, 3718–3730 (2015).
Integrated Design of Cathode and Separator for Lithium-Sulfur Battery
Authors: Pei Haijuan , Guo Rui , Li Yong , Liu Wen , Xie Jingying 
Published: February 2020

Lithium–sulfur (Li–S) battery is considered to be one of the most promising candidates for high energy density applications especially in electric vehicles and hybrid electric vehicles, due to low cost, environment friendliness, availability of resource materials, large theoretical specific capacity and specific energy of 1672 mAh g-1 and 2600 Wh kg-1, respectively. However, the actual specific capacity and energy are both far less than the theoretical values, in common sense, which is due to the poor utilization of sulfur and polysulfides.
To improve the performance of the cell and reduce the mass of non-active material, an integrated cathode and separator has been developed for Li-S batteries. The elemental sulfur and various conductive carbons were casted onto the separator directly, instead of the routine Al current collector, which makes the batteries lighter and more flexible. As shown in Fig.1, the integrated cathode with sulfur in the middle of the carbons layer has a three-dimensional electric conduction structure. Fig.2 displays the cycle performance of the cells with the integrated structure and routine structure, evidencing that the Li-S cell with the integrated cathode structure shows better cycle performance.

Acknowledgements

This work is supported by Shanghai Science and Technology Committee Rising-Star Program (15QB1402000).

Figure 1
Transformation of Environmentally Threatening Prosopis Juliflora into Tubular Carbon As Excellent Electrodes for Li-Ion Capacitors
Authors: Palanichamy Sennu , Lee Gyung Hwan , Park Sung Ho , Lee Yun Sung 
Published: February 2020

Sustainable renewable energy generation from sources that would otherwise be environmental pollutants and transportation of such energies for the desired applications would lead to significant global social and economic development. The commercially available energy storage devices such as supercapacitors and Li-ion batteries (LIB) energy and power densities are significantly lower than those necessary for applications in zero-emission transportation such as electric vehicles (EV, >150 Wh kg–1) & plug-in hybrid electric vehicles (P-HEV, 57 to 97 Wh kg–1).(1) The Li-ion hybrid electrochemical capacitor (Li-HEC) constructed with Li-ion insertion as anode and double-layer forming component as positive electrode, which provides the desired energy and power densities, respectively. (2, 3)
Here, the environmentally threatening and invasive weed of Prosopis juliflora is converted as electrode materials. Prior to testing the P. juliflora AC as an electrode for charge storage, we have carried out a systematic study on the preparation of AC from P. juliflora
. Firstly, the influence of the pore forming agent, i.e., KOH, and its capacitive behavior has been evaluated in symmetric configuration. Subsequently, the energy density has been increased by introducing a homemade insertion type electrode Li4Ti5O12 with P. julifloraderived AC as the supercapacitor component in a Li-HEC assembly. In addition, extensive physico-chemical properties, including XRD, BET surface area, Raman analysis, XPS, and SEM studies, were conducted and are described in detail.

References:

1. E. J. Cairns and P. Albertus, Annual Review of Chemical and Biomolecular Engineering, 1, 299 (2010).
2. V. Aravindan, J. Gnanaraj, Y.-S. Lee and S. Madhavi, Chemical Reviews, 114, 11619 (2014).
3. K. Naoi, S. Ishimoto, J.-i. Miyamoto and W. Naoi, Energy & Environmental Science, 5, 9363 (2012).

Figure 1. (a) SEM image of as prepared Prosopis juliflora carbon at 900 °C is naturally exist in tubular structure. (b) Plot of cyclic retention vs. cycle number and coulombic efficiency of KC21-900/LTO based Li-HEC at a current density of 1 A g–1. Here, the current density is based on the total mass loading of the electrode. Inset: typical charge-discharge curves for the first five cycles, (c) Ragone plot of KC21-900 based symmetric and Li-HEC configuration

Figure 1
Performance Changes in NCM523//Graphite Cells Resulting from High-Voltage Cycling
Authors: Gilbert James A , Klett Matilda , Bareno Javier , Miller Dean , Maroni Victor A. , Abraham Daniel P 
Published: February 2020

High-energy electrochemically-active materials are urgently needed to increase the energy density of lithium-ion batteries for vehicular applications. Layered-oxides are promising high-energy positive electrode materials. However, the performance of full cells containing these oxides degrades faster when cycled to high potentials (> 4.3 V w/graphite negative electrodes). In order to understand the origin of this performance loss, we conducted extensive aging tests in 2032-type coin cells and reference electrode (RE) cells. The observations and conclusions of our various tests will be highlighted during this presentation.
The coin cells in this study contain 1.6 cm2 area Li1.03(Ni0.5Co0.2Mn0.3)0.97O2-based (NCM523) positive and a graphite-based negative electrode (Gr); the electrolyte is 1.2M LiPF6 in EC:EMC (3:7 w/w) electrolyte (Gen 2). The reference electrode cells contain 20.3 cm2 area NCM523-positive and Gr-negative electrodes, two Celgard 2325 separators enveloping a LixSn RE, and a Li-metal RE external to the electrode sandwich. Cell cycling includes formation cycles followed by aging cycles; pulse-power and AC impedance measurements are made periodically throughout the cycling.
The Li-metal RE provides information on the positive and negative electrode potentials during full cell cycling; such information cannot be obtained from the coin cell data. For example, during cell formation, when the full cell is cycled between 3.0 and 4.4 V, the positive electrode cycles between 3.67 and 4.46 V vs. Li/Li+ and the negative electrode cycles between 0.67 and 0.06 V vs. Li/Li+. The electrode cycling potential ranges change during cell aging. Furthermore, electrode impedances measured with the LixSn RE also change during aging. We will highlight the reasons for these changes during the presentation.
In addition to the electrochemistry results we will discuss data obtained by various diagnostic techniques that include the following: Scanning electron microscopy, Raman spectroscopy, and X-ray diffraction. Our mechanistic understanding of the capacity fade and impedance rise of the NCM523//Gr cells will be discussed through these various data.

Acknowledgments

This document has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. Financial support from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, is gratefully acknowledged. Use of the Center for Nanoscale Materials and the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

Figure 1
Investigation of MnFeO3/Multiwalled Carbon Nanotubes Composite As Potential Anode for Lithium-Ion Batteries
Authors: Chandra Sekhar Bongu , Ragupathi Jeevani , Kalaiselvi Nallathamby 
Published: February 2020

MnFeO3, explored for its application in sensors, catalysis and semiconductors has been validated for the first time as anode for lithium-ion batteries, facilitated through the formation of composite containing multiwalled carbon nanotubes. MnFeO3 nanoparticles, derived from combustion method upon sonication with multiwalled carbon nanotubes (MWCNT) form MnFeO3/MWCNT composite that has been explored for the first time as anode material in lithium-ion battery applications. Scalable and highly reproducible sonochemical process has been adopted to form the composite, wherein the interweaved MWCNT ensures better electronic conductivity and the desirable pinning of pristine MnFeO3 particles with a conductive coating. The observed capacity and rate capability behavior of MnFeO3/MWCNT composite anode are found to be superior than pristine MnFeO3 anode in such a manner that a steady state reversible capacity of 840 mAh g-1 has been obtained at 0.5 A g-1 even after 50 cycles against an inferior capacity of 200 mAh g-1 offered by MnFeO3. Further, MnFeO3/MWCNT composite anode shows excellent rate capability and reversibility with respect to various current density conditions ranging from 0.5 to 10 A g-1, wherein appreciable capacity values of 2960 and 410 mAh g-1 have been obtained at 0.5 and 10 A g-1 respectively. The impressive electrochemical performance of MnFeO3/MWCNT composite anode could be correlated to the multifarious advantages offered by MWCNT, such as increase in the electronic conductivity, maintenance of structural stability upon cycling and mitigation of inherent and exorbitant volume changes observed upon cycling. In particular, the synergistic effect of conversion cum redox reaction triggered electrochemical activity of MnFeO3 and the increased electronic conductivity rendered by the conducting carbon network of MWCNT, possessing larger surface area and appreciable mechanical strength contributes to the improved electrochemical behaviour, observed with the currently prepared MnFeO3/MWCNT anode in a significant manner. These results suggest that the currently synthesized MnFeO3/MWCNT nanocomposite anode could be considered as a promising candidate for next generation hybrid energy storage applications. The present study is bestowed with the identification and demonstration of earth abundant, environment friendly and low cost metals viz., Mn and Fe based composite anode for high capacity and high rate lithium-ion battery applications, which is noteworthy.
Electrochemical Preparation of Fe2O3 Nanorods/Carbon Nanofiber Free-Standing Anode for Lithium Ion Batteries
Authors: Park Yiseul , Oh Misol , Baek Seong-Ho , Kim Jae Hyun 
Published: February 2020

Fe2O3 nanorod/carbon nanofiber (CNF) composites were prepared by the electrochemical deposition of Fe2O3 on a web of CNFs, which was then used as a free-standing anode. The conductive, three-dimensional structure of the CNF web allowed for the electrodeposition of the Fe2O3 nanorods, while its high conductivity made it possible to use the composite as a free-standing electrode in lithium-ion batteries. A free-standing electrode, which does not use polyber binder, substrate, and conductive additive, prevented a recution of rate-capability owing to the non-conductive polymer binder. In addition, it was easy and cheap to fabricate by a simplification of a process of cell preparation. The nanorod-like Fe2O3 structures could only be electrodeposited on the CNFs; flake-like Fe2O3 was formed on flat conductive glass substrates. It can be attributed to the different growth mechanism of Fe2O3 on the CNFs because of the large number of reaction sites on the CNFs, differences in the precursor concentration and diffusivity within the CNF web. The formation of aggregates of the Fe2O3 particles on thicker CNFs also indicated that the CNFs had determined the Fe2O3 growth mechanism. The synthesised Fe2O3/CNF composite electrode exhibited stable rate capacities at different current densities. This suggested that CNF-based composite did not exhibit the intrinsic disadvantages of Fe2O3. Finally, carbon coatings were deposited on the Fe2O3/CNF composites to further improve their electronic conductivity and rate capability. The strategy adopted in this study of using a web of CNFs as the substrate for the electrodeposition of Fe2O3 and of using the resulting composite material as a free-standing electrode or LIBs should also be applicable in the case of other metal oxide/CNF composites.
Li4Ti5O12/N-Doped Graphene Microspheres As High Rate Anode Materials for Lithium Ion Batteries
Authors: Jeong Jun Hui , Youn Hee-Chang , Choi Yeon Jun , Park Byung-Hoon , Kim Kwang-Bum 
Published: February 2020

Spinel Li4Ti5O12(LTO) has been demonstrated to be one of the most promising electrode materials for lithium-ion batteries due to flat voltage range (1.55V vs. Li/Li+), high reversible capacity (175 mAhg-1), and good cyclability during charge/discharge processes.
However, the electrochemical performance of LTO deteriorates with increasing charge/discharge rates due to its low electronic conductivity (10-9 Scm-1). Several strategies, such as particle size reduction to nanoscale, metal doping, surface modification and carbon coating, and formation of composite with carbonaceous materials, have been developed to enhance the electrochemical performance.
Especially, metal oxide with carbonaceous materials provides a high electrical conductivity, which can allow lithium ions and electrons to have an access readily to reaction sites of the metal oxide. Compared to other carbonaceous materials such as graphite, carbon black, and carbon nanotube, graphene a single layer of carbon atoms tightly packed in to a 2-dimensional honeycomb sp2 carbon lattice, has attracted a rapidly growing research interest owing to high conductivity (104 Scm-1), high surface area (2630 m2g-1) and good mechanical properties. Additionally, the electrical conductivity of graphene could be modified by nitrogen doping.
As mentioned above, LTO has poor electronic conductivity. Herein, we describe a novel strategy for the fabrication of LTO/N-doped Graphene microsphere composite by spray-drying method and annealing process. It makes micro N-graphene microsphere stuffed with LTO particles. The key strategy is to create a network between N-graphene and LTO particles, and the N-graphene can be embedded into the LTO materials to greatly improve the surface conductivity. The reversible capacity, especially rate performance of the LTO/N-doped Graphene microsphere in comparison with the bare LTO and LTO/graphene microspheres were evaluated.
Experimental results indicate that the LTO/N-doped Graphene microsphere can indeed deliver enhanced rate capability and good cyclic stability. Detailed synthetic procedure and electrochemical properties of LTO/N-doped Graphene microsphere will be presented at the meeting.
Free-Standing Oxide Nanotube Array Electrodes for High Energy Density and Power Density Li-Ion Batteries
Authors: Wei Wei , Björefors Fredrik , Edström Kristina , Nyholm Leif 
Published: February 2020

During the past few years, with the increasing power demand generated by applications from portable devices to electric vehicles, more and more emphasis is put on manufacturing high energy and power density Li-ion batteries, i.e., to maximize the capacities while retaining a high rate capability. So far, the studies have been mainly dedicated to the development of powder type electrode materials and relatively little attention has been paid to studies of other electrode architectures. While composite electrodes containing a mixture of the active material powders, binders and conductive additives still are commonly used, such electrodes often yield poor material utilization, undefined material/component arrangements and a lot of complex interfaces. In the present work, we demonstrate that various highly ordered, free-standing oxide nanotube array electrodes, fabricated by electrochemical anodization approaches, can be used either for high energy density and power density Li-ion microbattery applications or as model monolithic electrodes for electrode engineering studies. By using anatase TiO2 nanotube electrodes (as an example of an intercalation type material), an areal capacity of 0.37 mAh cm-2 (i.e., 40 mAh g-1) at a rate of 10C (using a (dis-)charge current density of 9 mA cm-2), and 1 mAh cm-2 (i.e., 91 mAh g-1) at a rate of C/5), can be achieved. [1] Well-defined monolithic anatase TiO2 nanotube electrodes with fine-tuned nanotube size gradients (including tube length, diameter and wall thickness) can also be manufactured using a bipolar electrochemistry approach. [2] The gradient nanotube electrodes can provide excellent rate performance, with capacities from of 0.16 mAh cm-2 or 169 mAh g-1 at a rate of C/5 to 0.04 mAh cm-2 or 42 mAh g-1 at a rate of 50C. In addition, free-standing Nb2O5 nanotube electrodes, which can be cycled for 10000 cycles with only a 20% loss of initial capacities, can provide unprecedented high-rate battery performances, i.e. the capacities from of 0.1 mAh cm-2 or 110 mAh g-1 at a rate of C/5 to 0.04 mAh cm-2 or 44 mAh g-1at a rate of 100C.[3] Some recent work carried out to investigate highly ordered Fe3O4 nanotubular/nanoporous electrodes as a prototype free-standing conversion electrode will also be described. References:[1] W. Wei, et al., submitted, 2015 ; [2] W. Wei, et al., Electrochim. Acta 2015, 176, 1393 ; [3] W. Wei, et al., in preparation, 2016