bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Binder Property and Interaction on Electrode Microstructure Formation in Energy Storage
Authors: Liu Zhixiao , Mukherjee Partha P. 
Published: February 2020

Energy storage, such as lithium-ion batteries (LIBs), is key enabler for grid energy storage and vehicle electrification. The electrode microstructure, which is affected by processing scheme, plays an important role in determining the electrode property and performance.1-5In the multiphase electrode slurry, physicochemical interactions affect the assembly of active material and conductive additive particles. Additionally, the pattern of nanoparticle assembly is also affected by the solvent evaporation rate.
Polymer-mediated nanoparticle assembly can be a promising method to control a composite microstructure.6 However, there are only a few studies focusing on the effect of binder interaction (such as binder molecular weight) on the electrode microstructure formation and the relative performance.7, 8

In the present study, we developed a mesoscale model accompanied by stochastic dynamics simulation to illustrate the influence of binder interaction and evaporation on microstructures during the electrode processing. Present simulations demonstrate that the lower drying temperature can produce electrode films with micropores as shown in Figs. 1 (a) ~ (c). The depth of micropores tends to increase as binder length (L) increases. Drying temperature affects binder distribution along thickness direction as shown in Fig. 1 (d). The lower drying temperature reduces the fraction of on-surface binder. Additionally, binder length also affects the binder distribution. It can be seen in Fig. 1 (d), that an increase of binder length is beneficial for keep high volume fraction of binder in the film which has implication in better mechanical stability of the electrode film.

Refernces

1. J. Li, B. L. Armstrong, J. Kiggans, C. Daniel, and D. L. Wood III, Langmuir,
28 (8), 3783-3790 (2012).
2. H. Zheng, R. Yang, G. Liu, X. Song, and V. S. Battaglia, The Journal of Physical Chemistry C,
116 (7), 4875-4882 (2012).
3. G. Liu, H. Zheng, S. Kim, Y. Deng, A. Minor, X. Song, and V. Battaglia, J Electrochem Soc,
155 (12), A887-A892 (2008).
4. Z. Liu and P. P. Mukherjee, J Electrochem Soc,
161 (8), E3248-E3258 (2014).
5. Z. Liu, V. Battaglia, and P. P. Mukherjee, Langmuir,
30 (50), 15102-15113 (2014).
6. P. Akcora, H. Liu, S. K. Kumar, J. Moll, Y. Li, B. C. Benicewicz, L. S. Schadler, D. Acehan, A. Z. Panagiotopoulos, V. Pryamitsyn, V. Ganesan, J. Ilavsky, P. Thiyagarajan, R. H. Colby, and J. F. Douglas, Nat Mater,
8 (4), 354-359 (2009).
7. B.-R. Lee and E.-S. Oh, The Journal of Physical Chemistry C,
117 (9), 4404-4409 (2013).
8. N. Tasić, Z. Branković, Z. Marinković-Stanojević, and G. Branković, Science of Sintering,
44 (3), 365-372 (2012).

Figure 1
Robust Fail-Safe Iteration Free Solvers for Battery Models
Authors: Pathak Manan , Sonawane Dayaram , Lawder Matthew T , Subramanian Venkat 
Published: February 2020

Mathematical models of batteries1, 3, 4 are dynamic systems. which are typically solved by using a finite difference or other discretization technique in the spatial direction and solving the resulting system of nonlinear differential algebraic equations (DAEs) in time2.
The resulting DAEs are stiff, often times ill-conditioned and many standard solvers fail to solve them. The complications in solving the system of DAEs also include the inability of the solvers to find consistent initial conditions for the algebraic variables5,6. Most stiff solvers include a Newton-Raphson type iterative methods to solve these stiff equations. (DASKR, RADAU, IDA7).
In this work, we propose a single-step iteration free approach to system initialization and simulation allowing for systems of DAEs to be solved using explicit ODE solvers without exact knowledge of the initial conditions for the algebraic variables. We will present this new solver which is guaranteed to not fail for any meaningful physical situations.
Acknowledgements

The work presented herein was funded in part by the Advanced Research Projects Agency – Energy (ARPA-E), U.S. Department of Energy, under Award Number DE-AR0000275.

References

Methekar, R. N., Ramadesigan, V., Pirkle, J. C. and Subramanian, V. R. A perturbation approach for consistent initialization of index-1 explicit differential-algebraic equations arising from battery model simulations. Computers & Chemical Engineering 2011; 35(11): 2227-2234.

Michelsen, M. L. Application of Semi-Implicit Runge-Kutta Methods for Integration of Ordinary and Partial-Differential Equations. Chem Eng J Bioch Eng 1977; 14(2): 107-112.

M. Doyle, T. F. Fuller and J. Newman, J. Electrochem. Soc., 140, 1526 (1993).

T. F. Fuller, M. Doyle and J. Newman, J. Electrochem. Soc., 141, 1 (1994).

Cash, J. R. Efficient numerical methods for the solution of stiff initial-value problems and differential algebraic equations. P Roy Soc a-Math Phy 2003; 459(2032): 797-815.

E. Hairer, G. Wanner, Solving Ordinary Differential Equations II: Stiff and Differential–algebraic Problems, second ed., Springer-Verlag, 1996.

IDA,[http://computation.llnl.gov/casc/sundials/main.html]
(Invited) Computational Insight and Design of Cathode Materials and Electrolytes for Li-O2 Batteries
Authors: Curtiss Larry , Lau Kah Chun , Assary Rajeev , Welland Michael , Liang Linyun , Redfern Paul , Wolf Dieter 
Published: February 2020

Rechargeable aprotic lithium-oxygen (Li-O2) batteries are the subject of much current research because their potential high energy density; however, many challenges remain for Li-O2 batteries. Computational studies of cathode and electrolyte materials for Li-O2 batteries can provide key insight into their materials properties as well as aid in the design of new improved materials. In this paper we report on density functional calculations and mesoscale level simulations being carried out to try to understand the properties of cathode materials and how they control the growth and nucleation mechanism, which result in different morphologies and affects the charge overpotentials. Design of new cathode materials based on the structure-function relationships found in these studies is discussed. In addition, we also report on electrolyte decomposition mechanisms that can occur in Li-O2 batteries due to surface reactions and solution phase reactions. The use of high throughput computational screening techniques for discovery of new electrolytes for Li-O2 batteries will be discussed. In this approach we effectively down-select large pools of candidates based on successive property evaluation.
(Invited) Density Functional Theory Modeling of Coupled Mechanical/Electrochemical Interfacial Processes during Li-Insertion into Silicon Anode
Authors: Leung Kevin , Soto Fernando , Balbuena Perla B 
Published: February 2020

Silicon anodes, unlike graphite widely used in commercial batteries, experience large (up to 400%) volumetric expansion after Li insertion during charging. This likely leads to unique SEI structures and formation mechanisms, especially at atomic lengthscales not readily probed using existing experimental techniques. We apply DFT modeling to model the incremental expansion of amorphous LixSi as the Li-content (“x”) increases; examine how such expansion stretches or even cracks the model passivating layers; and how such SEI evolution/degradation leads to additional electrolyte decomposition. First we create a series of amorphous LixSi slabs by incrementally increasing the Li content. The stoichiometry can range from LiSi to Li13Si4. The slabs are coated by a thin passivating layer (e.g., LiFz, which should form rapidly in the presence of FEC additives). During expansion, the surface films evolve, become stretched, or even crack. AIMD simulations of liquid ethylene carbonate (EC) films are then conducted on expanded LixSiy with stretched passivating LiFx layers. The instantaneous, electronic voltage, responsible for SEI formation, is periodically computed to ensure the modeling conditions conform to the experimental voltage window. The effect of spatial inhomogeneity, e.g., holes in the passivating layer, on inducing voltage ”hot-spots” that can accelerate electrolyte decomposition, are highlighted. To some extent, the modeling work represents very fast Li insertion, on the time scale of SEI formation. Despite this, studying the stretching and potential breaking of model SEI layers can provide valuable insight concernin potentially unique SEI behavior on Si anode surfaces.
This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, Subcontract No. 7060634 under the Batteries for Advanced Transportation Technologies (BATT) Program. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corpo ration, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

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(Invited) What's New with Metal-Oxygen Batteries? a Multi-Scale Perspective
Authors: Siegel Donald J 
Published: February 2020

Metal-oxygen batteries continue to attract interest due to their high theoretical specific energies. However, several challenges must to be overcome before these batteries can be viable. For example, in the case of Li-O2 systems a combination of sluggish charge transport within the Li2O2 discharge product and electrolyte decomposition at the electrolyte/Li2O2 interface have been proposed as limiting factors. This presentation will describe multi-scale computational studies aimed at revealing the mechanisms responsible for these limitations. Based on these findings, opportunities for improving cell performance will be discussed.
Thermodynamics and Kinetics of the Multi-Electron ε-VOPO4 cathode Across Two Lithium Insertion
Authors: Lin Yuh-Chieh , Wen Bohua , Quackenbush Nicholas F. , Piper Louis F.J. , Whittingham M. Stanley , Ong Shyue Ping 
Published: February 2020

LiVOPO4 is one of the few polyanion cathode materials that can reversibly insert/extract more than one lithium ion per transition metal and has a very high theoretical capacity of 318 mAh/g. Here, we present a detailed first principles and experimental investigation on ε-LixVOPO4 (0 ≤ x ≤ 2) to understand its structural evolution, thermodynamics and kinetics during lithium intercalation. We show that while no intermediate phases are predicted to be stable in the range of 0 ≤ x ≤ 1, first principles calculations predict two intermediate phases in the low voltage regime (1 ≤ x ≤ 2), in agreement with recent experiments.1 These intermediate phases are confirmed by V L-edge soft XAS and XRD data. The calculated voltage profile over 0 ≤ x ≤ 2 is also in excellent agreement with experiments. We predict decreasing phase stability with the incorporation of two Li into ε-VOPO4, suggesting that there are inherent challenges to achieving stable two-electron cycling without structural modification. We will also present a comprehensive analysis of the kinetics (ionic and electronic) of ε-LixVOPO4over the entire lithiation range. This work was supported as part of NECCES, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001294.
1. Z. Chen, Q. Chen, L. Chen, R. Zhang, H. Zhou, N. A. Chernova and M. S. Whittingham, J. Electrochem. Soc., 2013, 160, A1777
Electrodeposition from Liquid Metal Salts
Authors: Fransaer Jan 
Published: February 2020

Ionic liquids are ideal for performing electrochemical reactions which cannot be carried out in aqueous solutions, due to their wide electrochemical window, intrinsic electrical conductivity and large liquidus range. One drawback is the limited solubility of simple inorganic metal salts, such as chlorides and sulfates. The lack of solubility leads to a correspondingly low limiting current density. This disadvantage can be circumvented by making the metal ion a part of the ionic liquid in a so-called Liquid Metal Salt. A general formula is e.g. [M(L)x][A], with M a metal ion, L a neutral ligand and A a counter anion.
By making the metal ion a structural part of the ionic liquid, the concentration of metal ions can be as high as 3 mol dm-3 without the need to add a salt as metal source. Hence, even at 25 A dm-2 which is a large current in unstirred solutions, no sign of the decomposition of the ligand L or anion A could be detected in the metal deposits. These high current densities are explained by the fact that the electrochemical experiments are performed in a pure ionic liquid that acts as both the supporting electrolyte and the electrochemically active species, which is therefore present in a high concentration. Additionally, these Liquid Metal
Salts do not have a cathodic decomposition potential since their cathodic limit is the metal reduction. The use of solution additives, such as thiourea or benzotriazole, was investigated by Raman spectroscopy for their influence on the deposit morphology.
So far we have synthesized and tested Liquid Metal Salts based on copper, silver, lithium, zinc, cobalt, nickel and palladium. Investigated ligands are (o.a.) acetonitrile, alkylimidazoles, py-N-O and amines. These cations were combined with anions such as bistriflimide, triflate or nitrate.
These liquid metal salts show great promise in a wide variety of electrochemical applications.
(Invited) Self-Terminated Electrodeposition Reactions
Authors: Ahn Sang Hyun , Liu Yihua , Wang Rongyue , Gokcen Dincer , Hangarter Carlos M , Bertocci Ugo , Moffat Thomas 
Published: February 2020

In a recent publication Pt deposition at negative potentials revealed an unanticipated self-terminating characteristic that enables controlled deposition of Pt monolayer films from a K2PtCl4-NaCl electrolyte. In the case of Pt, the deposition reaction is quenched at potentials just negative of proton reduction by alteration of the double layer structure and adsorption properties induced by a saturated surface coverage of underpotential deposited hydrogen, (Hupd). The surface may be reactivated for Pt deposition by stepping the potential to more positive values where Hupd is oxidized and fresh sites for adsorption of PtCl4
2- become available. Periodic pulsing of the potential enables sequential deposition of additional Pt layers to fabricate films of desired thickness relevant to a range of advanced technologies in manner that is tantamount to wet atomic layer deposition (ALD). In the presence of iron group metal the Hupd induced suppression is lifted by underpotential deposition of the iron group metal as revealed in voltammetric studies of singular surfaces and thin film deposition studies of the binary Pt100-xNix and Pt100-xCox alloy. Bulk alloy formation is facilitated by ongoing Pt deposition that incorporates the iron group metals in accord with the excess enthalpy of alloy formation. This talk will present an update on the exploration of the generality of self-terminating deposition reaction to other chemical system such as Ir and other transition metals.
(Invited) Electroless Deposition of Ruthenium Using Sodium Borohydride Reducing Agent: A Mechanistic Study Using Electrochemical Quartz Crystal Microbalance
Authors: Joi Aniruddha , Zieliene Albina , Norkus Eugenijus , Tamasauskaite-Tamasiunaite Loreta , Dordi Yezdi 
Published: February 2020

Further miniaturization of interconnects and devices to keep up with Moore’s law in the 21st century requires materials innovation. Copper, as the interconnect metal has been the workhorse of the semiconductor industry for the past two decades. As wire dimensions shrink below 20 nm in future technology nodes, the ability of copper to meet the conductivity and reliability benchmarks is strained1. One metal that becomes attractive at smaller dimensions (<10 nm) is ruthenium, due to its high conductivity and electromigration resistance2. Traditional routes for metallization of ruthenium includes physical vapor (PVD), chemical vapor (CVD) and atomic layer deposition (ALD). PVD suffers from its line-of-sight, non-conformal deposition process that is not suitable for narrow, high aspect ratio geometries. CVD and ALD processes are slower and more expensive than PVD. Here we present an electroless deposition process (ELD) for ruthenium that overcomes some of the obstacles associated with the aforementioned processes. ELD is inherently selective which yields conformal coating in challenging geometries. Furthermore, ELD has lower cost of ownership due to relatively inexpensive precursors and significantly higher deposition rate than ALD and CVD. Here, sodium borohydride is used as the reducing agent for electroless deposition of Ru, and the effects of temperature, precursor and ligand concentrations on ruthenium growth rate are characterized. A linear increase in deposition rate is observed with increasing temperature and ruthenium concentration. A critical borohydride concentration is observed at ~2 g/L, where the maximum deposition rate is obtained. The mechanism of the ruthenium deposition process (reduction half-reaction) is further investigated via electrochemical quartz crystal microbalance (EQCM) analysis to probe the role of pH and complexation. Ru deposition on Cu initiates at a potential of -1.05 V vs. Ag/AgCl reference electrode, and further analysis indicates that a high pH of the electrolyte is needed to suppress any side reaction(s) and to form kinetically active ruthenium-hydroxy complexed species. Finally, some challenges to integration and different applications for an electroless deposited Ru are highlighted.

Figure 1: (a) Linear potential scan of the background electrolyte and the electrolyte containing Ru precursor. Increase in current density is observed at potential <-1.05 V vs. Ag/AgCl. Coupled quartz crystal microbalance analysis (b) confirms Ru deposition at potentials more cathodic than -1.05 V vs. Ag/AgCl.
References:
1. International Technology Roadmap for Semiconductors, www.itrs.net
2. K. Sankaran, S. Clima, M. Mees, C. Adelmann, Z. Tokei and G. Pourtois. Proceedings of the IEEE International Interconnect Technology Conference, 193 (2014)

Figure 1
Modification of Electrodeposited Co-Pd Alloy Catalysts By Superimposed High Magnetic Field
Authors: Zabinski Piotr , Mech Krzysztof , Banbur-Pawlowska Sylwia , Kowalik Remigiusz 
Published: February 2020

Palladium and its alloys have been a subject of interest in many research centers all over the world. Due to the price and accessibility of Pd, intensive tests are conducted aiming to invent alloys with catalytic properties similar to those of platinum, but much cheaper than palladium itself. Alloys of Co-Pd, Pd-Fe, Pd-Ni and Pd-Cr exhibit high catalytic activity for the four electron oxygen reduction reaction.
The properties of Co-Pd alloys for the hydrogen evolution reaction are close to the properties of pure platinum. This makes it possible to use them, for example, in fuel cells. Tests performed so far have demonstrated that the Pd-Co alloys are characterized by much better electrocatalytic properties for HER than pure palladium. Application of an external magnetic field during the deposition of an alloy causes an additional convection at the electrode surface through the magnetohydrodynamic effect (MHD), paramagnetic force and magnetic field gradient force. This additional convection results in changes of the alloy composition, structure and morphology, and these, in turn, affect the further properties as magnetic as catalytical of the produced alloys.
Magnetic field applied parallel to the surface of the electrode generates convection (magnetohydrodynamic effect MHD) of the electrolyte; it results in a laminar flow on the surface of the electrode which reduces the diffusion layer and increases the concentrations gradients. This results in change of the size of the grains and thus can also influence the texture and formation of various phases of the deposits. These various effects can be caused at the same time by the above mentioned convection but also by the magnetic properties, when the field is superimposed the growth in the direction of easier magnetization appears.
Optimal conditions of electrolytic deposition of cobalt matrix nanoalloys will be sought through selection of proper composition of electrolyte, changes of electrolysis parameters and by application of external electromagnetic field with intensity up to 12 Tesla.
Initial experiments, when the magnetic field was limited up to 1 T, show the improvement of catalytical properties together with increase of magnetic field orientated parallel to the surface of electrode. The influence of magnetic field with higher strength on electrodeposition of alloys with catalytical properties is needed to be clarified.
Acknowledgement
This work was supported by Polish National Science Center under grants 011/01/N/ST5/05509 and 2013/09/B/ST8/00211. This work was also supported by Polish Ministry of Science and Higher Education under grant IP2012/001072.
Intensity Modulated Photocurrent Spectroscopy (IMPS) Used to Detect Photoactive Intermediates during Ni-W Electrodeposition
Authors: Sun Shaopeng , Podlaha Elizabeth J 
Published: February 2020

Intensity modulated photocurrent spectroscopy (IMPS) is a technique conventionally used to characterize the semiconductor/electrolyte interface. It is used here in a new way, to track the presence of adsorbed, photoactive intermediates during the electrodeposition process, using Ni-W alloy electrodeposition as an example. Interest in Ni-W alloys are related to their high corrosion resistance, ability to catalyze the hydrogen evolution reaction from water, and superior wear resistance. The Ni-W deposition behavior from aqueous solutions is described as a coupled reaction mechanism and better understanding of the mechanism can help to control the deposit composition, which in turn is related to the resulting properties. To this end, IMPS was used to examine codeposition using an ammonia free citrate-boric acid electrolyte. The IMPS spectra was generated for different applied potentials. A significant current response to the incident modulated UV light was detected where steady state Ni-W codeposition takes place. The results confirm the presence of photoactive intermediates during codeposition, and demonstrates the first use of this technique in the electrodeposition process of a metallic alloy.
The attached figure shows a typical response during cathodic deposition of a Ni-W alloy at -1 V vs AglAgCl (42 wt % W) during IMPS compared to a potential where open circuit conditions are achieved and when clearly the alloy is treated anodically. A three electrode, single compartment cell with a flat quartz window was used with the following electrolyte: 0.375 M sodium citrate, 1.0 M boric acid, 0.075 M sodium tungstate, and 0.1 M nickel sulfate at a pH of 7. The response during deposition is significantly larger than that which occurs when a surface oxide is purposely generated; helping to valid that the deposition intermediate contributes to the observed impedance results. A simple model that includes the generated photocurrent contributing to an electrochemical reaction at the electrode/electrolyte interface or being lost to recombination was used to interpret the IMPS results. The dominate process occurring during IMPS is electron-hole pair recombination and thus, the modulated light does not significantly change the deposit composition, which was experimentally confirmed.

Acknowledgments

This material is based upon work supported by the U.S. National Science Foundation under Grant No.0957448.

Figure 1