bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-Situ Scanning Tunneling Microscopy and Electrochemical Quartz Crystal Microbalance Studies of the SEI Formation on Graphite Electrodes
Authors: Seidl Lukas , Ma Jiwei , Martens Sladjana , Mostafa Ehab , Schneider Oliver , Stimming Ulrich 
Published: February 2020

Electric vehicles and portable electronic devices depend on high performance energy storage technology like rechargeable Li ion batteries, whose successful operation requires high energy- and power-densities just as low cost, reliability, safety and long lifetime.1,2 The energy and power density of batteries, as well as their costs are mainly determined by the electrode materials, whereas safety, lifetime and efficiency are strongly affected by the properties of the Solid Electrolyte Interphase (SEI).3 In the past three decades research tried to deepen the understanding of the SEI by a large variety of experimental methods, ranging from basic electrochemistry over microscopic techniques to spectroscopic tools4. Questions regarding its formation mechanism, its morphological appearance and its chemical composition have been tackled, but there is still a lack of understanding on the molecular level.
In the mid-1990s M. Inaba et al. carried out a series of experiments about the SEI-formation on model graphite electrodes and the co-intercalation of Li+-ions together with their solvation shell using Electrochemical Scanning Tunneling Microscopy (EC-STM).5 EC-STM is a very powerful technique for surface studies, since it offers the possibility to in-situ image molecular processes at the electrode/electrolyte interface. In the present study, the SEI-formation was examined in depth by in-situ EC-STM on highly oriented pyrolytic graphite (HOPG) model electrodes both in commercial Li+-ion battery electrolytes as well as alternative electrolyte systems (see Figure 1). In addition, the Electrochemical Quartz Crystal Microbalance technique (EQCM) as another in-situ method gave further insights into the SEI-formation. Both in-situ techniques provided valuable information about the electrochemical characteristics of this system, leading to better understanding of the formation mechanism and the morphological appearance of the SEI.

Figure 1. In-Situ EC-STM study of the SEI-formation on HOPG in 1M LiPF6 in EC/DMC electrolyte: The surface is imaged while the potential (line) is scanned from 2.0 V vs. Li/Li+ to 1 V, held at this potential, and scanned back to 2 V. The y-axis of the STM image is converted to a time scale to correlate changes in morphology to the applied potential

1M. Armand, J.-M. Tarascon, Nature, 451 (2008) 652

2J. B. Goodenough, J. Solid State Electrochem, 16 (2012) 2019

3P. B. Balbuena, Y. Wang, Imperial College Press (2004), ISBN 1-86094-362-4

4H. Tavassol, J.W. Buthker, G.A. Ferguson, L.A. Curtiss, A.A. Gewirth, J. Electrochem. Soc., 159 (2012) A730-A738.

5M. Inaba, Z. Siroma, A. Funabiki, Z. Ogumi, T. Abe, Y. Mizutani, M. Asano, Langmuir, 19 (1996) 1535

Figure 1
Silicon-Graphite Electrode Performance in Lithium Ion Batteries: From Coin Cells to 500 Mah-Pouch Cells
Authors: Polzin Bryant J , Trask Stephen E , Lu Wenquan , Jansen Andrew N. 
Published: February 2020

Current lithium ion anode and cathode materials cannot meet the desired gravimetric and volumetric energy demands for hybrid electric vehicles (HEV), plug in hybrid electric vehicles (PHEV) and pure electric vehicles (EV). One way to improve the performance of these systems is to develop a high energy anode material. One system that has shown promise is the incorporation of silicon particles into the anode. Silicon by itself can have capacities up to 3000 mAh/g. While this value is impressive, there are a number of issues that present themselves when trying to use all of that capacity.
Argonne National Laboratory has taken up the task to create a silicon-based anode that could be used with the current lithium ion cathode materials to increase the gravimetric and volumetric energy of these systems. The capacity target for this electrode was chosen to be between 600-800 mAh/g (active material). By selecting this value, systems modeling has shown that this anode capacity matched with current cathode materials would produce the most cost effective and energy dense systems.
This presentation will first focus on some of the initial development of the anode formulation and processing issues encountered. From there, coin cell data (Figure 1) will be presented on the anode formulation and then the presentation will conclude with xx3450 pouch cell data. Qualitative and quantitative data will be examined for each of the sections.
As a final point, the silicon anode formulation has been made into a practical and usable electrode and matched to the Electrode Library which has been created by the Cell Analysis, Modeling, and Prototyping (CAMP) Facility. The silicon based anode, graphite based anodes, and various cathodes are available in the Electrode Library for use in the battery research community.

Acknowledgment:

Support from Peter Faguy and David Howell of the U.S. Department of Energy’s Office of Vehicle Technologies Program is gratefully acknowledged. This work was performed under the auspices of the U.S. Department of Energy, Office of Vehicle Technologies, under Contract no. DE-AC02-06CH11357

Figure 1
Role of 1, 3-Propane Sultone and Vinylene Carbonate in Solid Electrolyte Interface (SEI) Formation and Gas Generation
Authors: Lucht Brett L , Garsuch Arnd , Gasteiger Hubert A , Zhang Bo , Metzger Michael , Meini Stefano , Payne Martin , Solchenbach Sophie 
Published: February 2020

The cycling performance, ex-situ surface analysis, and in-situ gas analysis of lithium ion batteries containing the widely used electrolyte additives VC and PS has been investigated. All of the electrolytes have good cycling performance at 25°C. However, the electrolytes containing additives have better discharge capacity retention and coulombic efficiency upon cycling at 55°C. Analysis of the differential capacity plots suggest that both VC and PS are reduced prior to the carbonates and alter the structure of the anode SEI. Ex-situ surface analysis confirms structural differences of the anode SEI. Electrodes cycled in the presence of PS contain lithium alkyl sulphonate (RSO3Li) on the surface of the anodes. The presence of the lithium alkyl sulfonate leads to higher lithium ion conductivity of the anode SEI. Electrodes cycled with added VC contain poly(VC) in the anode SEI. The presence of the poly(VC) leads to improved stability of the SEI. Anodes cycled with both VC and PS contain lithium alkyl sulphonate and poly(VC) which leads to an SEI with both high conductivity and high thermal stability. In-situ gas analysis shows that both additives, VC and PS, are able to reduce the ethylene evolution during SEI formation by nearly 70 %. The formation of poly(VC) for electrodes cycled in VC is accompanied by CO2 evolution. The presence of the lithium sulfonate for PS leads to a lower onset potential of ethylene evolution. For VC, the only gaseous byproduct during reduction is CO2, while PS shows no gaseous reduction products. The combination of both additives leads to a superposition of the described phenomena. The reduction of gas evolution during SEI formation would allow a faster and easier industrial formation procedure for Li-ion batteries.
A Study of e- Transport through Li2O2, the Main Discharge Product in the Li-O2 Battery
Authors: Knudsen Kristian Bastholm , Jensen Søren Højgaard , Luntz Alan C. , Hjelm Johan 
Published: February 2020

In the field of energy storage devices the pursuit for cheap, high energy density, reliable secondary batteries is at the top of the agenda. The Li-O2battery is one of the possible technologies that, in theory, should be able to close the gap, which exists between the present state-of-the-art Li-ion technologies and the demand placed on batteries by technologies such as electrical vehicles [1].
However, the Li-O2 battery still suffers greatly from high overpotentials during oxygen reduction and evolution reactions (discharge and charge, respectively), poor rechargeability, and decomposition of salts and solvents etc. [2] [3]. In order to improve the electrochemical performance of the Li-O2batteries; it is crucial to understand the fundamental mechanisms that governs and limits the system during electrochemical operation.
Here we present a redox probing study of the charge transfer across the deposition product lithium peroxide, Li2O2, using outer-sphere redox shuttles: cobaltocene, ferrocene, and decamethylferrocene. The change in heterogeneous electron transfer exchange rate as a function of the potential and the Li2O2 layer thickness (~state of charge) was determined using electrochemical impedance spectroscopy. The attenuation of the electron transfer exchange rate with film thickness is dependent on the probing potential, indicating that hole tunneling is the dominant process for charge transfer through Li2O2supporting previous work by Luntz et al. [4].
Additionally, this work includes the determination of diffusion coefficients and concentrations of the redox shuttles and the superoxide ion, in a 1,2-dimethoxyethane based electrolyte.

References

[1]
S. A. Freunberger, P. G. Bruce, L. J. Hardwick et J.-M. Tarascon, «Li-O2 and Li-S batteries with high energy storage,» Nature Materials, vol. 11, pp. 19-29, 2012.

[2]
B. D. McCloskey, A. Valery, A. C. Luntz, S. R. Gowda, G. M. Wallraff, J. M. Garcia, T. Mori et L. E. Krupp, «Combining Accurate O2 and Li2O2 Assays to Separate Discharge and Charge stability Limitations in Nonaqueous Li-O2 Batteries,» J. Phys. Chem. Lett., vol. 4, pp. 2989-2993, 2013.

[3]
R. Younesi, M. Hahlin, F. Björefors, P. Johansson et K. Edström, «Li-O2 Battery Degradation by Lithium Peroxide (Li2O2): A Model Study,» Chem. Mater., vol. 25, pp. 77-84, 2013.

[4]
A. C. Luntz, V. Viswanathan, J. Voss, J. B. Varley, J. K. Nørskov, R. Scheffler and A. Speidel, "Tunneling and Polaron Charge Transport through Li2O2 in Li-O2 Batteries," J. Phys. Chem. Lett., vol. 4, pp. 3494-3499, 2013.
25mg NMR Studies of Mg-Ion Battery Materials
Authors: Proffit Danielle L. , Kim Chunjoong , Senguttuvan Premkuvar , Duffort Victor , Nazar Linda F , Cabana Jordi , Burrell Anthony K. , Vaughey John T. , Key Baris 
Published: February 2020

Multivalent-ion chemistries such as Mg-ion are emerging as alternative battery systems to Li-ion. Current Mg-ion chemistries are limited to relatively low voltages and relatively low reversible specific capacities (1-2). Recent research on potential high voltage Mg-ion cathode materials and alternative anode materials such as transition metal oxides and metal alloys have highlighted the urgent need to understand structure activity relationships and insertion/intercalation phenomenon for development of such systems (3). Solid state NMR is a powerful tool to investigate local structure and insertion/intercalation phenomena, particularly for batteries as shown for Li-ion chemistries with 6Li and 7Li NMR (4, 5). However, the low natural abundance (10%) of the NMR active Mg isotope (25Mg), highly quadrupolar nuclear spin of 25Mg (spin 5/2) and very low gyromagnetic ratio (i.e 30.6 MHz Larmor frequency relative to 1H = 500 MHz) limits the effective use of 25Mg NMR for solid Mg-ion battery materials (6). In this work, despite the challenges of 25Mg NMR, our recent efforts to characterize Mg environments in cathode materials such as MgMn2O4 spinels, MgV2O5, in anode materials such as h-TiO2 and Mg-Sn alloys will be presented. Chemical magnesiation using dibutylmagnesium and preliminary electrochemical (de)mangesiation and the structral changes induced will be discussed. The results will summarize the effectiveness of the method in distinguishing side reactions or undesirable conversion reactions, including amorphous phases, from intercalation phenomenon.
References:
1. D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, and E. Levi, Nature,
407 (6805), 724-727 (2000).
2. H. D. Yoo, I. Shterenberg, Y. Gofer, G. Gershinsky, N. Pour, and D. Aurbach, Energ Environ Sci,
6 (8), 2265-2279 (2013).
3. Magnesium Batteries 1 and 2, 224th Electrochemical Society Meeting, San Francisco CA, 2013
4. C. P. Grey and N. Dupre, Chem. Rev. (Washington, DC, U. S.), 104, 4493 (2004).
5. B. Key, R. Bhattacharyya, M. Morcrette, V. Seznec, J. M. Tarascon and C. P. Grey, Journal of the American Chemical Society, 131, 9239 (2009).
6. R. Dupree and M. E. Smith, Journal of the Chemical Society-Chemical Communications, 1483 (1988).
Modeling the Si-Current Collector Interface in Li-Ion Battery
Authors: Wang Miao , Xiao Xinran 
Published: February 2020

Si is a promising anode material for Li-ion batteries (LIB) due to its high energy density. Nevertheless, the large volume variation of Si during lithiation/delithiation cycles presents a great challenge to its structural integrity in LIBs. To this end, a wide variety of Si electrode designs have been attempted. It has been shown that reducing its size to nano scale can effectively prevent the fracture of the Si electrode itself. However, failure may still occur at interfacial regions between the Si electrode and other components such as the current collector due to deformation mismatch. The detached Si becomes isolated from the electronic pathway and hence the cell capacity degrades.
Understanding the deformation and stress-strain relationship at the Si-current collector interface is an important step in engineering durable, high capacity LIBs. In this work, a multiphysics microstructure-resolved model [1] was used to simulate the deformation of Si nanorods on a Ni substrate reported by Bella et al [2]. The Si was described by an elasto-plastic law with a finite strain formulation. The Li concentration dependence of the Young’s modulus and yield strength was considered. Ni was modeled as an elasto-plastic material. The interface between Si and Ni was modeled as a region with unique properties.
The results revealed that the interfacial properties not only affect the deformed shape of the Si nanorod and Ni substrate but also the stress triaxiality in the system. To reproduce the deformation as in the experiment, a parameter study with different interfacial properties was carried out. The interfacial properties resulting in the best correlation with the experiment were identified. The microstructure-resolved model will then be used to investigate the structure design of LIBs with Si anode.

Wu, Wei, Xinran Xiao, Miao Wang, and Xiaosong Huang. “A Microstructural Resolved Model for the Stress Analysis of Lithium-Ion Batteries.” Journal of The Electrochemical Society 161, no. 5 (January 1, 2014): A803–A813.

Berla, Lucas A., Seok Woo Lee, Ill Ryu, Yi Cui, and William D. Nix. “Robustness of Amorphous Silicon during the Initial Lithiation/delithiation Cycle.” Journal of Power Sources 258 (July 15, 2014): 253–59.
Anodic Dissolution in Dual-Ion Batteries: Development of Protection Layers for Current Collectors
Authors: Teucher Georg , Van Gestel Tim , Uhlenbruck Sven , Guillon Olivier , Eichel Rüdiger-Albrecht , Meister Paul , Winter Martin 
Published: February 2020

One aspect of the current research on lithium ion batteries is the increase of the cell voltage to improve the energy density. In innovative dual-ion cells, graphite intercalation compounds are used for both electrodes. Consequently, a simultaneous intercalation of lithium ions into the anode and the corresponding salt anions into the cathode is possible and enables voltage values above 5 V vs. Li/Li+. Established liquid electrolytes, consisting of carbonates and lithium hexafluorophosphate, do not resist these conditions. Therefore, we replace this mixture by ethyl methanesulfonate and organic lithium salts, having a good electrochemical performance also at higher temperatures. Now, it is the challenge to overcome the anodic dissolution of the aluminum current collector triggered by fluorinated anions like bis(trifluoromethylsulfonyl)imide (TFSI-). Our approach to protect the metal against anodic dissolution is the deposition of an only electronically conductive, defect-free and mechanically as well as electrochemically stable layer. We test different material compositions in the range of oxidic ceramics. First of all semiconductors like alumina doped zinc oxide show promising results to meet the requirements. The preparation is based on a sol-gel route combined with several wet-chemical coating methods, because these are easily adjustable to different substrate dimensions. Ceramic thin layers of around 100 nm thickness are deposited on aluminum foil and mainly investigated by scanning electron microscopy, X-ray diffraction and secondary ion mass spectrometry. Additionally, we present conductivity measurements and the electrochemical performance tested with cyclic voltammetry.
Voltage Fade in Lmr-NMC Oxides Cycled below the Activation Plateau
Authors: Bareno Javier , Li Yan , Bettge Martin , Benedek Roy , Iddir Hakim , Chen Zonghai , Bloom Ira , Abraham Daniel P 
Published: February 2020

A common feature of lithium-excess layered oxides, nominally of composition xLi2MnO3
•(1-x)LiMO2 (M = transition metal) is a high-voltage plateau (~4.5 V vs. Li/Li+) in their capacity-voltage profile during the first delithiation cycle. This plateau is believed to result from activation of the Li2MnO3 component, which makes additional lithium available for electrochemical cycling. Once activated (i.e., cycled beyond the activation plateau) the voltage v. capacity characteristic of LMR-NMC oxides is known to decrease continuously with cycling, resulting in a progressive loss of energy density. This phenomenon is commonly referred to as voltage fade.
In this talk we show evidence of voltage fade well below the activation plateau. We argue that this voltage fade results from a gradual accumulation of spinel environments in the crystal structure. Some of these spinel sites result from lithium deficiencies during oxide synthesis and are likely to be at the particle surfaces; other sites result from the migration of transition metal atoms in the partially-delithiated LiMO2 component into the lithium planes during electrochemical cycling.
(Invited) Electrolytes for Li-Ion Batteries Based on High Voltage Cathodes
Authors: Jow T. Richard , Delp Samuel A. , Allen Joshua L. , Allen Jan L. , Borodin Oleg , Olguin Marco 
Published: February 2020

The electrolyte is a critical part of today’s Li-ion batteries. The state-of-the-art Li-ion batteries, which are made of cathodes such as 4.1 V LiCoO2 and 3.4 V LiFePO4 and graphite anode, function well in the state-of-the-art electrolytes made of LiPF6 in carbonate solvent mixtures such as EC and EMC with additive such as VC. The reason for this compatibility is attributed to the facts that the cathodes are within the stability range of the electrolytes and the ability of the electrolyte for forming a solid electrolyte interphase (SEI) layer on graphite, protecting the graphite anode from reacting with the electrolytes.
When developing higher energy density Li-ion batteries based on higher voltage cathodes such as 4.7 V LiNi0.5Mn1.5O4 (LNMO) and 4.8 V LiCoPO4 (LCP), the oxidative stability of the state-of-the-art electrolytes is in question. Furthermore, the stability of the high voltage cathodes themselves is also not certain. Efforts in improving the stability of LNMO and LCP through substitutions have yielded better performing cathodes in terms of improved capacity retention and coulombic efficiency.1, 2

The search for electrolytes that work with the high voltage cathodes has been intensive. Molecular modeling to understand the oxidative stability of Li-ion electrolytes has been active.3 This paper will review our recent efforts on electrolyte development for improving the electrochemical performance of the high voltage cathodes in Li-ion batteries.
References

A. Manthiram, Phys.Chem. Lett. 2011, 2, 176-184.

J. L. Allen, T. R. Jow, J. Wolfenstine, J. Power Sources 2011, 196, 8656.

O. Borodin, W. Behl, T. R. Jow, J. Phys. Chem. C 2013, 117, 8661-8682.
Graphene Folding in Si Rich Carbon Nanofibers for Highly Stable, High Capacity Li-Ion Battery Anodes
Authors: Fei Ling , Joo Yong Lak 
Published: February 2020

Silicon has received tremendous attention as lithium ion battery anode due to its high theoretical capacity) and low working potential versus Li+/Li. The major problems associated with Si are its poor conductivity and large volume change during the lithium insertion and extraction process. Previously, we prepared Si/carbon nanofibers with improved electrochemical performance of Si via environmental-friendly and cost-effective water-based electrospinning procedure [1]. In this work, we continued our effort to further improve the system. Graphene, possessing excellent mechanical property, high conductivity, and good stability, has been widely applied in the energy storage field. Herein, graphene was introduced to the Si/C nanofibers for the first time. It was found increasing graphene amount helps keep the fibers morphology after carbonization. And the fiber cross section images reveal that micrometer graphene is heavily folded into the nanometer fibers during electrospinning, while Si NPs are incorporated into the folds with nanospace inbetween. When applied as the anode material in LIBs, the composites show a high reversible capacity of ~1600 mAh g-1 at a charging rate of 100 mA/g and a stable capacity of 890 mAh g-1 at 1A/g after 50 cycles with 98% capacity retention. The interconnected graphene network not only ensures excellent conductivity, but also serves as a buffering matrix for the mechanic stress caused by volume change; the nanospace between Si NPs and graphene provides the space needed for volume expansion.
1. Y.S. Kim, K.W. Kim, D. Cho, N.S. Hansen, J. Lee, and Y.L. Joo, "Silicon-Rich Carbon Hybrid Nanofibers from Water-Based Spinning: The Synergy Between Silicon and Carbon for Li-ion Battery Anode Application", ChemElectroChem 1, 220-226 (2014).
Using X-Ray Diffraction to Map the Electrochemical Spatial Inhomogeneity within Li-Ion Batteries
Authors: Okasinski John , Abraham Daniel P 
Published: February 2020

Many limitations of current lithium-ion battery technologies originate from the degradation of the battery’s active materials, with micromechanical fatigue damage playing a critical role. This microstructural damage results from mechanical strains and stresses induced by volume changes during the extraction and insertion of lithium ions. In addition, structural changes that result from composition-induced phase changes and interfacial reactions with the electrolyte also contribute to the build-up of mechanical stresses. The specific challenge undertaken is the characterization of the spatial inhomogeneity within the battery cell electrodes during electrochemical cycling via x-ray diffraction.
The Li1+xTM1-xO2compounds are leading candidates for the next generation of lithium batteries. Due to constraints imposed by the complex electrode morphology, the mechanical stresses often lead to cracking within, and at the boundaries between, oxide particles. We have conducted a systematic experimental study to determine the evolution in these oxide materials as a function of electrode cycling, position in the battery cell, and aging conditions.
High-energy x-rays are able to penetrate through large amounts of material so that the diffraction signal probes the entire depth of the battery cells, including multiple layers of aluminum and copper current collectors and transition-metal laden electrodes. The diffraction signal provides information on the lattice parameters for the active materials, which changes as the battery cell is cycled. Results for a study of the spatial inhomogeneity that is present in a NMC523(+)/Graphite(-) battery with a prismatic form factor will be discussed.