bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrolyte and Electrode Design for Dynamic Windows Based on Reversible Metal Electrodeposition
Authors: Strand Michael , Hernandez Tyler , Slotcavage Dan , Barile Christopher J. , McGehee Michael D. 
Published: February 2020

Dynamic windows, which allow electronic control over light and heat flux, enable responsive environments free of glare and unwanted heat. Electronic control over traditionally static performance characteristics like visible light transmittance and solar heat gain coefficients will allow dynamic windows to be integrated with algorithms to optimize for energy efficiency and comfort. Dynamic windows based on reversible metal electrodeposition (RME) represent an exciting, new class of electrochromic devices. Metals are ideal light-modulators for dynamic windows because they can be color neutral, inert, photostable, and opaque at 20-50 nanometer thicknesses. Our team recently demonstrated metal-based dynamic windows that boast cheap processing, fast switching, and stable performance over thousands of cycles on the 25 cm2 scale.
Several technical challenges hinder further scalability of the technology. Indium tin oxide (ITO), the most ubiquitous transparent conductor, has a relatively high sheet resistance. By Ohm’s Law, maintaining a uniform current density across ITO electrodes necessitates a voltage drop proportional to the electrode area. Large-scale RME windows must be engineered with a tolerance to the voltage drop across the transparent electrodes in order to maintain optical uniformity. Additionally, undesired side reactions like the hydrogen evolution reaction (HER) set strict limits on the potentials that may be applied in aqueous electrolytes. The ideal system will enable uniform nucleation and growth of metal films over the potential range set by side reactions inherent to aqueous electrolytes, and the voltage drop inherent to transparent conductors.
Prudent design of electrode structure and electrolyte composition enable uniform and reversible electrodeposition over large areas. First, we demonstrate a scalable, self-assembly process to fabricate transparent electrodes functionalized with Pt nanoparticles. The nanoparticles enable site-selective control over nucleation of metal deposits. Second, we establish selection criteria for the use of polymeric levelling agents in reversible metal electrodeposition systems. By understanding the binding affinity between levelling agents and metal ions in our system, we access a range of electrodeposit morphologies that offer tunable control over optical properties. Finally, we demonstrate 100 cm2 RME-based dynamic windows that switch uniformly from a clear state (60% transmission) to an opaque state (<5% transmission) in less than one minute.

Figure 1
Effects of Microstructure of Nickel Electrodeposits on the Growth of Tin-Nickel Intermetallic Compound and Joint Reliability
Authors: Park MiSeok , Ryu TaeSeon , Lee SunSoo , Kim KangSoo , Kwon HyukSang 
Published: February 2020

The mechanical breakage and electrical open failure of the flipchip bump interconnection are main issues that retarding the scale shrinkage of the 3D interconnections.
In this study, the effects of the microstructure of the nickel electrodeposits on the growth of Sn-Ni intermetallic compound (IMC) and on the electro-migration (EM) reliability were investigatged. The crystal structure of the Ni diffusion barrier can be controlled by addition of additives in electroplating bath. When both coumarin and cis-2-butene-1,4-diol were contained in the bath, extremely fine grain Ni electrodeposits were deposited by the synergistic effects of the additives. The growth rate of Ni3Sn4 IMC formed on the interface between the extremely fine grain structured Ni layer and Sn solder is higher than that of the IMC formed on the interface between the large grain structured Ni layer and Sn solder. The EM failure stage corresponds to large void propagation at the Sn-Ni3Sn4 interface due to volume consumption of Sn for IMC formation. The results of STEM analysis in an early stage of the heat treatment of the solder demonstrated that substantial quantities of Ni atoms were dominantly dissolved into the liquid Sn layer. Ni3Sn4 IMC was mainly formed on the finely grained Ni layer due to the high dissolution of Ni atoms into the solute Sn during the reflow process. IMC growth was suppressed at the interface between the large and fine grain structured area. This study suggests a robust concept of the vertical structure of Ni diffusion barrier having a multi layered Ni microstructure, which can reinforce an adhesion property as well as diffusion barrier properties

Figure 1
Understanding the Effects of Sulfate/Bisulfate Ions on Electrolytes for Vanadium/Sulfuric Acid Redox Flow Batteries
Authors: Donnelly Daniel J , McDonnell Elias , Lawton Jamie S. , Arruda Thomas M 
Published: February 2020

Redox flow batteries are a promising utility scale energy storage technology, recognized for the safe storage of surplus energy harnessed by wind and solar. Of particular promise is the all vanadium redox flow battery (VRFB) which relies on two redox couples of VO2
+ (V5+)/VO2+(V4+) on the cathodic side and V3+/V2+ on the anodic side. Significant efforts in recent years have focused on the optimization of operating conditions of VRFBs required for widespread commercialization. However many of these endeavors rely on incomplete or inappropriate data applied to specific systems, (e.g. wrong diffusion coefficients under specific conditions) which is necessary for a more complete and robust model.
One such phenomena inherent to the operation of a VRFB is proton and vanadium ion crossover.1–4 Proton transport is a requirement for the electrochemical reactions and to maintain charge balance. However, in practice vanadium ions also transport across the membrane causing parasitic and other unknown effects. For example, it is difficult to monitor changes to proton concentration (e.g. pH) as chemical treatment (titration) is clouded by the precipitation of VO(OH)2, and pH measurements under operational conditions are impossible or impractical.
This presentation will report our fundamental measurements of VRFB electrolytes by first investigating concentration effects of SO4
2-/HSO4
- to gain insight on the discharged (VO2+) electrolyte and the chemical equilibrium with a goal of being able to identify proton concentration. This understanding will allow for the determination of proton concentrations of the charged electrolytes and shed light on vanadium crossover which has occurred during charging. Those data will be compared to our experimental electron paramagnetic spectroscopy EPR vanadium crossover data.

J. S. Lawton, A. M. Jones, Z. Tang, M. Lindsey, and T. Zawodzinski, J. Electrochem. Soc. , 164, A2987–A2991 (2017) http://jes.ecsdl.org/content/164/13/A2987.abstract.

J. S. Lawton et al., J. Electrochem. Soc., 163, A5229–A5235 (2016).

R. A. Elgammal, Z. Tang, C.-N. Sun, J. Lawton, and T. A. Zawodzinski, Electrochim. Acta, 237, 1–11 (2017) http://linkinghub.elsevier.com/retrieve/pii/S0013468617306138.

R. M. Darling, a. Z. Weber, M. C. Tucker, and M. L. Perry, J. Electrochem. Soc., 163, A5014–A5022 (2015) http://jes.ecsdl.org/cgi/doi/10.1149/2.0031601jes.
A High-Voltage Aqueous Flow Battery Based on Highly Soluble Organometallic Materials
Authors: Li Bin , Hollas Aaron , Nie Zimin , Wei Xiaoliang , Wang Wei , Reed David , Sprenkle Vincent 
Published: February 2020

Redox flow batteries (RFBs) systems, as one of the most promising electrical energy storage systems, provide an alternative solution to the problems of balancing power generation and consumption. These batteries are not only able to provide energy where and when it is required but also reduce the high capital cost of managing peak demands on the grid as well as large investments in grid infrastructures. Cost, reliability and safety are the most important factors to be considered to develop these systems. Because of good safety characteristics and high power densities (e.g., VRBs), aqueous systems have attracted widespread interest. The most widely studied redox species, vanadium, is expensive and toxic in its oxidized form. Therefore, organic or organometallic redox species could be used since they can offer more flexibility to tune the redox activity, redox potential, solubility, and stability.
Here, we will introduce a new low-cost aqueous redox flow battery system based on organometallic redox species. The theoretical energy density of this system can reach 90 Wh/L. Fig. 1(a) and (b) show the typical charge-discharge curves of this system (before and after electrolytes optimization) and cell efficiency performances over cycling, respectively (after optimization). It can be seen the open circuit voltage (OCV) increases from 1.52 V to 1.83 V and the system shows a very stable cell performance. The underlying mechanisms will be discussed.

Figure 1
Blackwater Disinfection Using Potentiodynamic Methods and Surface-Modified Electrochemical Packed Bed Electrode Materials
Authors: Thostenson James O. , Mourouvin Rayane , Hangarter Carlos , Ngaboyamahina Edgard , Hawkins Brian T. , Sellgren Katelyn L. , Rossman Carolyn , Parker Charles B. , Deshusses Marc A. , Stoner Brian R. , Glass Jeffrey T. 
Published: February 2020

The present work investigates the use of an electrochemical packed bed reactor (EPBR) for improving the energy efficiency of disinfecting human-generated blackwater. Potentiostatic and potentiodynamic treatment methods are used to compare packed-bed electrodes of magnelli-phase titanium-oxide, granularized activated carbon (GAC), and surface modified forms of both.
Our results highlight the differences in energy expenditure, oxidant generation, and EPBR operating conditions, as well as time needed for disinfection of blackwater as a function of packed bed electrode material and potentiometric treatment method. It is proposed that potentiodynamic treatment methods offer a more energy efficient and practical solution to treating blackwater than potentiostatic methods. Moreover, the benefits and drawbacks of using magneli-phase titanium oxide compared to common granularized carbon electrode materials are highlighted by correlating disinfection to energy expenditure and electrochemically generated oxidants. Reactive oxygen species, such as H2O2, and chlorine containing species, such as Cl2, are quantified and correlated to the reduction of bacterial concentration for each electrode material and treatment method. Lastly, the effects of flow-rate, particle size, and blackwater composition are correlated to the optimal conditions for blackwater disinfection.
Is There Room for Theory in Data Science? Encoding Physics into Machine Learning Algorithms
Authors: Dawson-Elli Neal , Subramanian Venkat R. 
Published: February 2020

Batteries are complex electrochemical devices whose short-term and long-term operational lives are highly dependent on their construction, materials, and use cases. Models have been developed and used to improve the performance of batteries by providing different material design, model based control and model based battery management systems1.
There is a recent trend in data-science-based approaches for modeling different devices and processes2,3. It has been demonstrated that using machine learning techniques can retain 99.9% of the accuracy of a complex model while improving solve time by four orders of magnitude, which can allow for the use of high accuracy models in a real-time control scenario3.
When data science techniques, and machine learning in particular, are implemented in battery systems, they are typically used as black boxes to predict battery behavior4. In this talk, we will highlight why this approach is ill suited for use in physics-based battery models, which are highly nonlinear, and how an understanding of the system can improve the result of the machine learning effort for use in optimization and control, while still allowing for the prediction of important internal states. Additionally, we will highlight ways to employ the flexibility of machine learning algorithms to allow for more accurate state estimation and voltage prediction.
Real-time model-based control has demonstrated significant improvements in time remaining, state of charge, and state of health, even using simple equivalent circuit models5. By reducing the order and solve time of higher complexity models, we believe that better predictability is possible.

Acknowledgments

The authors thank the United States Department of Energy (DOE) for the financial support for this work though the Advanced Research Projects Agency – Energy (ARPA-E) award #DEAR0000275, as well as the Clean Energy Institute (CEI) through the DIRECT program at the University of Washington.

References

Y. Dai, and V. Srinivasan,. J. Electrochem. Soc., 163, A406 (2016).

D. A. C. Beck, J. M. Carothers, V. R. Subramanian, and J. Pfaendtner, “Data science: Accelerating innovation and discovery in chemical engineering,” AIChE J., vol. 62, no. 5, pp. 1402–1416, May 2016.

Blake R. Hough, author. Jim Pfaendtner, degree supervisor. 2016 Thesis (Ph. D.)--University of Washington,2016.

J. Liu, A. Saxena, K. Goebel, B. Saha, and W. Wang, “An Adaptive Recurrent Neural Network for Remaining Useful Life Prediction of Lithium-ion Batteries,” NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER, Oct. 2010.

Williard, Nick, Wei He, and Michael Pecht. "Model Based Battery Management System for Condition Based Maintenance." Technical Program for MFPT 2012, The Prognostics and Health Management Solutions Conference - PHM: Driving Efficient Operations and Maintenance, 2012
Electrochemical Properties of Anatase-Type TiO2 Nanoparticles with Different Morphology
Authors: Juhasz Gergely 
Published: February 2020

Yamauchi and her group recently showed that anatase type TiO2 electrodes can be used for electrochemical reduction of carboxylic acids to alcohols [1]. So far this reaction was demonstrated only for oxalic acid with an efficiency very sensitive to the preparation conditions of the anatase electrode. One possible explanation of such sensitivity electrochemical activity to preparation conditions is that the morphology of the surface has deep impact on the electrochemical processes. To improve the efficiency as well as to understand what factors limit the reduction of other acids, we studied the effect of morphology on the electronic structure of anatase nanoparticles using Density Functional Tight Binding (DFTB) method. Since only nanoparticles of anatase up to 5 nm are thermodynamically stable, we focused on nanoparticles of 2-4 nm and assumed that morphological differences of the electrodes can be described with the help of such particle models.
The edges and peaks of nanoparticles contains of 4- and 5- coordinated Ti ions, which can be responsible for smaller band gap and strong reactivity of the particles. We performed extensive calculations to study the water and acid absorption on the edges and faces of nanoparticles to identify the most probable coordination environment of these Ti ions. We also studied the energy and overlap between LUMO (conduction band) of the nanoparticles and substrates, as these orbitals play important role in electrochemical reduction reactions. Our computational work offers new understanding for optimization of titania electrode surfaces for electrochemical reaction.
The work was supported by CREST, JST and the computations were partially performed using Research Center for Computational Science, Okazaki, Japan.
Reference:
[1] R. Watanabe, M. Yamauchi, M. Sadakiyo, R. Abe and T. Takeguchi, Energy Environ. Sci., 2015, 8,
1456–1462

Figure 1
Charge Transport and Stability of a Semiconductor-Solution Interface Under Electrical Bias from First Principles
Authors: Campbell Quinn , Dabo Ismaila 
Published: February 2020

Solar energy is the most abundant energy source available to humankind; this energy cannot be harnessed on demand, however, due to the variability of sunlight. Artificial photosynthesis offers a sustainable way to overcome that variability through the photocatalytic conversion of solar power into chemical fuels at a semiconductor–electrolyte interface. Although considerable progress has been made in simulating the bulk properties of semiconductors from first principles, much less has been done to address the electrochemical response of semiconductor–electrolyte interfaces under realistic environmental conditions. We present broadly applicable and highly transferable computational techniques to simulate semiconductor–electrolyte interfaces. By introducing a continuum model of the semiconductor and electrolyte regions surrounding the quantum-mechanical interfacial layer, our model enables the self-consistent determination of the electrical response of a semiconductor-solution interface, including the atomistic effects of charge trapping at interfacial surface states. Using this, we develop a new description of the semiconductor-solution interface allowing us to predict the electrical response, stability, and equilibrium Schottky barrier of a photoelectrode as a function of different surface chemistries. This allows researchers to optimize materials selection for both charge transport and stability, leading to more efficient and practical artificial photosynthesis systems.
Reference:
Campbell and Dabo, Physical Review B 95, 205308 (2017).
Modeling Lithium Growth in Symmetric Cells
Authors: Chen Jerry , Subramaniam Akshay , Lee Seong Beom , Geise Natalie R , Kasse Robert M. , Toney Michael F , Subramanian Venkat R. 
Published: February 2020

Lithium-metal batteries are receiving great attention in recent years as an anode material. It has a higher theoretical specific capacity (3860 mAh∙g-1) compared to the graphite (372 mAh∙g-1) used in conventional Lithium-ion batteries.1 However, the capacity fade resulted from unexpected dead lithium, and dendrite growth is a major issue that causes shorter cycle life and possible internal short circuits during operation.
The purpose of this study is to develop a continuum model that captures the dynamics of lithium metal deposition and stripping during repeated cycling of a lithium-metal cell. The repeated deposition and stripping of Lithium accounts for the presence of a heterogeneous growth of Lithium foil (anode) in a battery electrode. One can take advantage of the simplicity of symmetric cells to understand electrodes and electrolyte in a controlled applied potential.2 The symmetric cell consists of the same materials on both electrodes, so the average potential of the system is zero. This study will compare the continuum model with experimental data for a Li/Li symmetric cell.
The mathematical model used in this study is based on the concentrated solution theory models developed by Newman and coworkers.3-5 The mass transport of the Li-ion in the electrolyte, neglecting migration, is governed by Fick’s law. A modified Ohm’s law for the liquid electrolyte phase is considered and the Butler-Volmer equation is accounted for lithium metal deposition and stripping at the electrode.
The system will be studied with one-dimensional modeling coupled with a moving boundary representation of lithium stripping and plating.6 Some experimental variations such as high current density cases will also be considered. The one-dimensional model will then be extended to two-dimensional modeling to understand the trend of heterogeneous plating/growth of Lithium metal.

Acknowledgements

The authors would like to thank for the financial support of this work by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the DOE through the Advanced Battery Material Research (BMR) Program (Battery500 consortium) and the Clean Energy Institute (CEI) at the University of Washington and the Washington Research Foundation (WRF) for their partial monetary support during this work.

References

J. Qian, W. A. Henderson, W. Xu, P. Bhattacharya, M. Engelhard, O. Borodin and J.-G. Zhang, Nature communications, 6 (2015).

J. C. Burns, L. J. Krause, D.-B. Le, L. D. Jensen, A. J. Smith, D. Xiong, and J. R. Dahn. J. Electrochem. Soc.,
158, A1417-A1422 (2011).

M. Doyle, T. F. Fuller, and J. Newman, J. Electrochem. Soc., 140, 1526–1533 (1993).

V. Srinivasan and J. Newman, J. Electrochem. Soc. , 151, A1517–A1529 (2004)

S.-L. Wu, A. E. Javier, D. Devaux, N. P. Balsara, and V. Srinivasan, J. Electrochem. Soc. , 161, A1836–A1843

Q. Zhang and R. E. White, J. Electrochem. Soc. , 154, A587–A596 (2007)
Estimation of Transport and Kinetic Parameters of Vanadium Redox Batteries Using Static Cells
Authors: Lee Seong Beom , Pratt Harry D. , Anderson Travis M. , Mitra Kishalay , Chalamala Babu R. , Subramanian Venkat R. 
Published: February 2020

Redox Flow Batteries (RFBs) are receiving significant attention as a promising technology for grid storage applications.1 While there has been great progress in experimental aspects of flow battery technology, there is a lack of modeling approaches to rapidly evaluate system performance. For example, a common practice has been to determine parameters in mathematical RFB models either through conducting experiments or based on the information available in the literature.2,3,5 However, it is not easy to investigate all parameters for models through this way, and there are occasions when important information, such as diffusion coefficients and rate constants of ions, is not studied. In addition, the parameters needed for modeling charge-discharge are not always available.
In this presentation, we demonstrate that an optimization-based robust modeling framework, which is based on a physics-based electrochemical engineering model and parameter estimation techniques,2-5 is useful in studying and analyzing RFB systems. We have studied aspects of capacity loss/fade, kinetics, and transport phenomena of the system and further optimized our model using a laboratory-scale all-vanadium redox static cell setup. The practical impact of this work will be reviewed by providing executable files that enable to identify the performance of redox batteries without the need for software installation and a priori programming knowledge.

Acknowledgements

This work was supported by the Clean Energy Institute located in University of Washington, Seattle and Washington Research Foundation. The battery experimental work has been supported by program manager Dr. Imre Gyuk through the U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

References

K. T. Cho, P. Ridgway, A. Z. Weber, S. Haussener, V. Battaglia, and V. Srinivasan, Journal of The Electrochemical Society,
159 (11), A1806-A1815 (2012)..

K. Knehr, E. Agar, C. Dennison, A. Kalidindi, and E. Kumbur, Journal of The Electrochemical Society,
159 (9), A1446-A1459 (2012).

A. Shah, R. Tangirala, R. Singh, R. Wills, and F. Walsh, Journal of the Electrochemical society,
158 (6), A671-A677 (2011).

A. Tang, J. Bao, and M. Skyllas-Kazacos, Journal of Power Sources,
196 (24), 10737-10747 (2011).

P. A. Boettcher, E. Agar, C. Dennison, and E. C. Kumbur, Journal of The Electrochemical Society,
163 (1), A5244-A5252 (2016).