bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-Walled Carbon Nanotubes (SWCNTs) for Protein Engineering Applications
Authors: Wu Shang-Jung , Zubkovs Vitalijs , Boghossian Ardemis Anoush
Published: February 2020

Protein engineering is a technique that has allowed researchers to overcome billions of years of evolution to create unnatural proteins that have been re-programmed to function and interact in ways unfounded in nature. It has been used to engineer proteins for a breadth of new purposes. This technique allows researchers to change the function of the protein by modifying its structure. Though a theoretical understanding of the relationship between the protein structure and function is helpful, unfortunately, the structure-function relation in the vast majority of proteins remains unknown.  Directed evolution is a powerful protein engineering method that circumvents the need to define the structure-function relation of a protein. Briefly, after introducing random mutations to the protein, the collection of mutated proteins is screened to identify proteins with the new, desired function. The proteins with beneficial mutations are then isolated and mutated once more, and the process is repeated until the new protein function has been optimized. Scientists use this strategy to modify and/or improve protein properties, including stability, fluorescence, activity, and affinity to a specific target. One primary challenge in this method is developing a high-throughput screen for evaluating protein function. Researchers have established several high-throughput techniques to screen protein activities effectively using, for example, fluorescence-activated cell sorting or in vitro compartmentalization. However, these methods are largely limited to specific proteins and cannot be readily generalized.

In our work, we use single-walled carbon nanotubes (SWCNTs) in a novel platform for investigating the functionality of a protein. SWCNTs emit fluorescence in the near-infrared spectral region between 900 nm and 1500 nm, a region that lies outside the optical window of most proteins and biomaterials in general. Further, SWCNTs demonstrate single-molecule sensitivities, with fluorescence emissions changing in response to perturbations in the charge, dielectric constant, and pH of the environment. We have exploited this sensitivity by interfacing SWCNTs with proteins that induce local environmental changes when active, thus allowing us to monitor protein activity by measuring the resulting changes to the SWCNT fluorescence. Combined with a moderate to high-throughput approach for acquiring SWCNT fluorescence, this platform provides biologists with a new tool for expediting the protein discovery process and engineering previously intractable proteins.
Single-Walled Carbon Nanotubes for the Quantification of Biomarkers in Biofluids
Authors: Harvey Jackson Dean , Baker Hanan , Li Xinghuo , Jena Prakrit Vaibhav , Heller Daniel A
Published: February 2020

As optical sensors, single-walled carbon nanotubes (SWCNTs) have properties that make them ideally suited for detection of biologically important analytes. Carbon nanotubes exhibit band gap fluorescence which does not photobleach or blink, and their fluorescent properties can be modulated by changes in their immediate environment. Tissue transparent emission, biocompatibility, and versatile modes of optical response make SWCNTs uniquely valuable optical biosensors. Using these properties, we have rationally designed SWCNT-based sensors for enhanced quantification of biomarkers in biofluids for diagnostic applications and for the study of fundamental biological processes.
Engineering Smart Wrappings for Next Generation Single-Walled Carbon Nanotube (SWCNT) Sensors
Authors: Kupis-Rozmyslowicz Justyna , Zubkovs Vitalijs , Ravi Sudharshan , Boghossian Ardemis Anoush
Published: February 2020

Semiconducting Single-Walled Carbon Nanotubes (SWCNTs) have a unique combination of optical, chemical, and physical properties that render them suitable for a broad range of applications1–3.  Since SWCNTs are composed exclusively of surface atoms, the fluorescence emission of the nanotubes is very sensitive to the surrounding environment, enabling single-molecule detection limits that are especially desirable for biosensing applications. The selectivity of SWCNT-based fluorescence sensors can be tuned by engineering a polymer wrapping that covers the nanotube surface, imparting the nanotube with molecular recognition capabilities.  The challenge in creating these near-infrared (NIR) fluorescence sensors lies with tuning the specificity of the sensor by altering the wrapping properties. Though the exact mechanism by which polymers render surface selectivity is an area of active area of research4, researchers have been nonetheless able to engineer wrappings by screening an assortment of SWCNTs wrapped in various polymers and monitoring fluorescence changes in response to different analytes.

In contrast to this empirical approach, we have developed ”smart” wrappings capable of pre-defined molecular recognition towards a specific analyte of interest. By applying established synthetic and biological techniques for engineering specificity, our platform provides an interdisciplinary approach towards exploring the underlying molecular mechanism and versatility in tuning optical SWCNT-based sensors. The results of this work provide a seminal proof-of-concept approach in developing smart sensing technologies.

References

(1)      Han, C.; Doepke, A.; Cho, W.; Likodimos, V.; De La Cruz, A. a.; Back, T.; Heineman, W. R.; Halsall, H. B.; Shanov, V. N.; Schulz, M. J.; Falaras, P.; Dionysiou, D. D. Adv. Funct. Mater.
2013, 23(14), 1807–1816.

(2)      Choi, Y.-E.; Kwak, J.-W.; Park, J. W. Sensors
2010, 10(1), 428–455.

(3)      Liu, Z.; Chen, K.; Davis, C.; Sherlock, S.; Cao, Q.; Chen, X.; Dai, H. Cancer Res.
2008, 68(16), 6652–6660.

(4)      Z. W. Ulissi, J. Zhang, V. Sresht, D. Blankschtein, M. S. Strano,  Langmuir
2015, 31(1), 628–636.
Applying the Ionic Field-Effect Photoluminescence of Semiconducting Carbon Nanotubes for Circuit-Free Electroanalytics
Authors: Horoszko Christopher Peter , Jena Prakrit Vaibhav , Roxbury Daniel , Rotkin Slava V. , Martel Richard , Heller Daniel A
Published: February 2020

Semiconducting single-walled carbon nanotubes (SWCNTs) exhibit unique photophysical processes from the visible to near-infrared that are ascribed to excitation and decay of excitonic transitions. Here we show that polyelectrolytic dispersants and aqueous electrolytes interact directly with charge carriers in the semiconducting nanotubes, resulting in carrier modulation that can be probed through photoluminescence (PL) intensity and frequency changes. Laser photocarrier generation may therefore induce a potential on the nanotube which interacts, through screening and adsorption, with solvent ions, described by ionic activity in the environment. A systematic exploration of various environmental parameters such as the type of polyelectrolyte dispersant and amphoteric surface is investigated to gain increased sensitivity for eventual use in modern potentiometry. Based upon the nanotube’s demonstrated role in double-layer and pseudo-capacitors, we developed models to explain observed phenomena and propose nanotubes can serve as circuit-free optical electrodes for electroanalytical applications on surfaces and cell membranes.

SVR was partially supported by National Science Foundation (ECCS-1509786)
(Invited) Spectral Characteristics of Cryogenic Carbon Nanotubes
Authors: Högele Alexander
Published: February 2020

Pristine semiconducting carbon nanotubes are commonly pictured as one-dimensional solid-state systems that host diffusive excitons at room temperature. At cryogenic conditions, however, the photophysics of carbon nanotubes are dominated by exciton localization stemming from accidental disorder or deterministic covalent side-wall functionalization. On the basis of our photoluminescence studies of individual carbon nanotubes at low temperatures we will discuss the spectral signatures of exciton localization and highlight the effect of the dielectric environment on the spectral characteristics of single nanotube emission.
(Invited) Phenomena in Mass-Transport Electrochemical Impedance Spectroscopy at Channel Electrodes
Authors: Holm Thomas , Ingdal Mats , Fanavoll Espen Vinge , Sunde Svein , Seland Frode , Harrington David A.
Published: February 2020

Microfluidic devices in general and channel electrodes in particular offer a wide variety of opportunities for analytical electrochemistry, especially as an easily manufactured rotating disk analog. In terms of this, electrochemical impedance spectroscopy as a method is a quickly recorded method that allows for fast characterization of the system. However, channel electrodes are not uniformly accessible, which greatly complicates the numerical treatment of the mass-transport to these electrodes. Using a reversible hexaammineruthenium(II/III) redox couple, the mass-transport impedance was measured, shown in Fig. 1a, and modelled using commercially available numerical software (Comsol Multiphysics ®). The results using numerical modelling were discussed in terms of common assumptions and used as a benchmark to test the validity of these approximations [1]. In addition, a new method using galvanostatic impedance spectroscopy at the upstream electrode and detecting the frequency dependent potential at a downstream electrode was discussed, Fig. 1b. Potentially, this allows for quick acquisition of geometric, kinetic and mass-transport parameters to allow quick characterization of a double channel electrode setup.

[1] T. Holm, M. Ingdal, E.V. Fanavoll, S. Sunde, F. Seland, D.A. Harrington, Electrochimica Acta 202 (2016) p. 84.

Figure 1
(Invited) Mechanisms of Inhibition of Corrosion of Metal Reinforcements for Eco Friendly Concrete Containing a Biological Admixture
Authors: Feugeas Françoise , Chakri Sara , Belhaj Essia , Sutter Eliane , Vivier Vincent , Meylheuc Thierry , Tribollet Bernard
Published: February 2020

The corrosion of steel in concrete is an important phenomenon of degradation of reinforced concrete structures, which starts with the breakdown of the passive layer on steel surface. Reinforcing steel in concrete is usually passivated due to the formation of a protective oxide layer that remains stable in the high alkaline surrounding pore solution. However, carbonation and contamination with chlorides induce passive film breakdown and pitting corrosion initiation. Thus, corrosion inhibitors can be added to fresh concrete as admixtures. A new eco-friendly bio-admixture (BA) produced with extra-cellular substances from a Gram-negative bacteria (Pseudomonas) was tested as inhibitor of corrosion. BA was added at concentration of 10 v/v % to various simulated electrolytes representative of concrete pore solutions (CPS) extracted from different concrete mixtures (CEM I, CEM II and CEM III; w/c = 0.45). The objectives were to study the influence of (1) the chemical composition of CPS and (2) the bio-admixture on the electrochemical behaviour and the surface chemical composition of C15 carbon steel, used for reinforcement of building concrete. Electrochemical measurements: corrosion potential Ecorr
as a function of time, polarization curves, electrochemical impedance spectroscopy were performed first in 0.1 M NaOH reference solution to understand the electrochemical behaviour of C15 mild steel by and then compared to those obtained in simulated CPS without or with BA. The pH of the synthetic CPS was adjusted to 13. The electrochemical results were combined to surface reflectivity. Experiments were also carried out in chlorides solution in order to study the effect of BA in localized corrosion conditions. The estimation of the oxide layer thickness using the Cole-Cole approach confirmed the presence of an oxide layer in an extended cathodic potential range in presence of BA.
Influence of C-Rate on Impedance Spectra in Lithium-Ion Rechargeable Batteries By in-Situ EIS
Authors: Kato Hirotaka , Hoshi Yoshinao , Shitanda Isao , Itagaki Masayuki
Published: February 2020

Electrochemical impedance spectroscopy (EIS) has been used for the investigation of electrochemical properties in lithium-ion rechargeable batteries (LIRB). Our group applied a nonstationary impedance spectroscopy to evaluation of LIRB1). The theory of this method was proposed by Stoynov et al.2). It allows the simultaneous measurement of the charge-discharge curves and impedance spectra of LIRB. We previously reported that three impedance spectra for full cell and positive and negative electrodes were determined by arranging a reference electrode in a laboratory cell of LIRB 3). We named in-situ EIS for this method and the influence of C-rate on the impedance spectra of both electrodes was investigated by in-situ EIS in the present study.

3D impedance spectra of positive and negative electrodes during charge at the 3 C-rate were measured by in-situ EIS. The 3D impedance of the full cell and positive and negative electrodes whose axes were real and imaginary parts and time was determined precisely. The impedance spectrum of the positive electrode described the two capacitive loops originating from film resistance and charge transfer resistance (R
ct). The instantaneous impedance was determined at arbitrary time from 3D impedance plot. The R
ct of negative electrode was determined by the curve-fitting using the equivalent circuit from 3D impedance plots.  It demonstrated that the R
ct during charge was larger than that during discharge in the positive electrode and smaller than that during discharge in the negative electrode. The interpretation of the hysteresis of R
ct observed in charge-discharge sequence was discussed in the present study.

 

References:

 

[1] M. Itagaki, N. Kobari, S. Yotsuda, K. Watanabe, S. Kinoshita, M. Ue, J. Power Sources, 135 (2004) 55-261.

[2] Z. B. Stoynov, B. S. Savova – Stoynov, J. Electroanal. Chem., 183 (1985) 133.

[3] M. Itagaki, K. Honda, Y. Hoshi, I. Shitanda, J
. Electroanal. Chem. 737 (2015) 78-84.
(Invited) Versatile Hydrogen Separations at Intermediate Temperatures with Solid Acid Membranes
Authors: Papandrew Alexander B. , Wilson David L. , Zawodzinski Thomas A.
Published: February 2020

Scalable, economical, on-demand hydrogen production from easily transported feedstocks may be an accelerant to the dawn of the long-prophesied hydrogen economy. An appropriately selective separation scheme could be used to produce ultra-pure hydrogen from a mixture of gases, allowing hydrogen to be mixed into existing natural gas pipelines. Alternately, gas-to-liquid methods can be used to produce transportable liquids, such as methanol, that can be converted to hydrogen as necessary.

The economics of these prospective courses of action demand that any such separation route must rely on inexpensive membranes, omit expensive catalysts, and limit stack-level materials costs. Electrochemical systems based on the anhydrous crystalline proton conductor CsH2PO4 (CDP) meet these standards. Operating at an intermediate temperature of 250 C, CDP-based devices can incorporate heterogeneous catalysts at the cell level to effect in-situ reforming of complex fuels such as methanol. A further benefit of intermediate-temperature operation is the extreme impurity tolerance of nonplatinum anode catalysts, including ruthenium.

In this contribution, the versatile array of separation schemes accessible using CDP-based membrane is assessed. Separations from simulated reformate streams as well as coupled heterogeneous-electrochemical cells for hydrogen production directly from hydrocarbons will be discussed.
Lithium Conducting Solid Electrolytes for Electrolysis of Lithium Tritide and Enrichment of Lithium-6
Authors: Olson Luke Christopher , Garcia-Diaz Brenda L. , Colon-Mercado Hector , Teprovich Joseph
Published: February 2020

Lithium stable, lithium conducting electrolytes may improve methods to attain high tritium breeding yields required by many current D-T fusion energy production designs. Two ways such an electrolyte could aid is by reducing one unit of operation from the current baseline method from the process of tritium extraction from the breeding blanket, and by enrichment of lithium-6 from natural lithium to allow for use of a lithium-6 enriched blanket in combination with blanket neutron multipliers to attain a higher breeding per fusion neutron.

Lithium tritide (LiT) is generated as a by-product of a tritium reaction with lithium cooling blanket material in fusion reactors for tritium breeding and power production. Recovery of tritium from the blanket materials is important to prevent environmental release and to recover valuable material. The Maroni process is the leading method to recover LiT from the lithium blanket using a molten salt liquid-liquid extraction method. The Maroni process can introduce salt components into the fusion reactor if separation is not complete and that can cause corrosion and activation of the salt components. SRNL has developed a direct LiT electrolysis method in the lithium blanket material using solid lithium ion conductors and has shown the evolution of hydrogen from the Li/LiH material during electrolysis. This method has been demonstrated at SRNL and results will be discussed.

The U.S. has historically stockpiled lithium-6 and lithium-7 for use in nuclear applications. These stockpiles of lithium isotopes are being depleted and the U.S. closed production facilities in the 1980's. The longest operating plants in the U.S. used the column exchange (COLEX) process, which utilized an Hg-Li amalgam that preferentially forms with lithium-6. The operation of these plants resulted in significant environmental contamination with mercury (Hg). SRNL is now conducting research to use the same type of electrolyte as used for LiT electrolysis to enrich lithium in lithium-6. This research is to develop a high temperature method for lithium-6 enrichment that includes conduction of lithium-6 through a solid state electrolyte and the formation of a molten Li-Bi alloy. Both the solid state conduction of Li and the formation of the Li-Bi alloy can potentially lead to enrichment of lithium-6 based on current research findings and thermodynamic modeling. Combining the conduction and alloying steps will make it possible to create a smaller and more efficient separation process. The use of bismuth (Bi) is much more environmentally friendly than Hg and has a similar energetic change, which assists the separation process. Results to date will be discussed.
Highly Stable Dual-Phase Y0.8Ca0.2Cr0.8Co0.2O3 - Sm0.2Ce0.8O1.9 ceramic Composite Membrane for Oxygen Separation
Authors: Yoon Kyung Joong , Marina Olga A
Published: February 2020

High-temperature oxygen transport membranes based on mixed ionic- and electronic-conducting (MIEC) ceramics are receiving increasing attention due to their potential applications for high-purity oxygen production, oxyfuel combustion, hydrogen/syngas production, coal gasification, and waste recovery. Dense MIEC membranes exclusively allow the permeation of oxygen ions in the presence of an oxygen partial pressure gradient because the oxygen ionic flux is counterbalanced by the flux of electrons to form an internal short circuit.

In this work, a highly stable ceramic composite membrane composed of Ca- and Co-doped yttrium chromite, Y0.8Ca0.2Cr0.8Co0.2O3 (YCCC), and samaria-doped ceria, Sm0.2Ce0.8O1.9 (SDC), is demonstrated for oxygen separation. Homogeneously dispersed nano-scale composite powders were synthesized by a single-step combustion process based on the glycine-nitrate method. Dense composite membranes were achieved having submicron grain sizes and well-percolated electronic and ionic conduction pathways. Densification of the composite membrane was assisted by liquid phase sintering caused by cobalt-doping in yttrium chromite, and gas-tight membranes are fabricated at 1400oC. The YCCC and SDC phases were chemically and thermo-mechanically compatible at both processing and operating temperatures. The composite membrane exhibited an oxygen permeation flux comparable to those of the state-of-the-art single-phase membrane materials and excellent stability in harsh operating conditions under a H2-CO2 environment for long-term operation, which suggests potential application in various combustion and fuel production processes.
Understanding High Capacity in Li-Rich 3d Cathode Materials
Authors: Luo Kun , Roberts Matthew , Bruce Peter G.
Published: February 2020

Lithium rich layered cathodes, which offer increased capacity, have, for several years, been regarded as one of the next major advances, able to store charge by invoking transition metal and oxygen redox processes in the same material. However, they are still challenged by problems such irreversible first cycle capacity, voltage fade on cycling related to changes in the structure. Recently important work has been carried out to better understand the origin of the high capacity and the voltage fade.

In this contribution we shall present data probing the nature of the O redox states in Li rich 3d transition metal oxides, on the nature of O loss probed by isotopic substitution and on the degree of oxygen loss vs oxygen redox. We shall also report on a new sol-gel synthesis for Li1.2Mn0.54Ni0.13Co0.13O2. The electrochemical performance is shown in Figure 1. The cycling stability of the material is good with a capacity of ~250 mAh g-1 maintained after 100 cycles.

Figure 1
A Techno-Economic Assessment of Cylindrical Spiral-Wound Lithium Ion Batteries: Can the Huge Factories Achieve Their Cost Goals?
Authors: Whitacre Jay , Ciez Rebecca
Published: February 2020

This talk will examine the techno-economics of Li-ion battery production with a focus on assessing the potential economies of scale that are purported for very large factories. A full front-to-back manufacturing model has been developed to address this question. The model is based on the Argonne BatPac tool that was originally created to describe the production of prismatic pouch configuration cells and has been extended to describe spiral-wound 18650 cells. Three different cathode chemistries have been considered: NCA, LMO, or NMC, and the costs of producing cells and packs at different volumes with different supply chain inputs are assessed. Further, an analysis on the impact of the market price of lithium-containing precursors on battery and back costing will be offered.

Our findings suggest that there is an absolute minimum in production cost for this format of these cells and this minimum is higher than values commonly described in the media. We also suggest that the price of lithium has little impact on cell and pack costing on a per kWh basis. We will offer a complete accounting of our analysis and an assessment of what materials and manufacturing changes stand to have the largest cost impact when producing cells and packs at a massive scale.
Li5FeO4 Li Source Additive Fixing Irreversibility in Li-Ion Batteries
Authors: Lin Chi-Kai , Su Xin , Lu Wenquan , Wang Xiaoping , Johnson Christopher
Published: February 2020

The initial irreversible capacity loss (ICL) in Li-ion batteries (LIB) occurs at both the anode and cathode materials. For the cathode, mostly interfacial losses are seen. However, the anode is typically more severe due to the creation of the solid-electrolyte interphase or SEI that consumes lithium in the cell on the first cycle, that passivates the carbon (graphite) electrode surface that enables further cycling at decent energy and coulombic efficiencies. However deleterious lithium consuming reactions continue to occur; caused by other reasons, such as decomposition of electrode materials, electrolyte additives, or side reactions that are not beneficial but all consuming. As a result, the number of lithium-ions available in the cell for cycling is decreased, leading to unmitigated decrease of the cell capacity and energy content. 

In this study, advanced high-performance lithium-ion cells and batteries that contain high-lithium-content additives such as Li5FeO4 or ‘LFO’ are used in the LIBs. Such additives improve the lithium-ion cell by electrochemically releasing large quantities of sacrificial lithium on the first formation cycle to treat too large irreversible capacity losses (ICL) (Figure 1). Additional benefits also include improved cycle-over-cycle coulombic efficiency in such cells. These solid powder oxide-based lithium-containing additives are enabled by co-blending with an active material cathode (e.g.; nickel manganese cobalt, NMC, or lithium cobalt oxide, LCO, or nickel cobalt aluminum or NCA) into an electrode in an as-prepared state. Such co-blended cathodes, when properly cell-balanced and thus paired with high-capacity and high energy/capacity containing advanced anode electrodes such as silicon, silicon oxide, or tin-containing intermetallic alloys, or high-capacity hard carbons, and graphite anodes thus results in a higher energy dense lithium-ion cell than previous state-of-art.

Figure 1. Voltage profiles of various LIB materials including Li-source additive Li5FeO4.

Acknowledgements

This work is supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. This work was supported as part of the Center for Electrochemical Energy Science (CEES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences.

Figure 1
Substantial Oxygen Flux in Fluorite-Rich Dual-Phase Membrane By Tailoring the Surface
Authors: Joo Jong Hoon , Yu Ji Haeng , Yoo Chung-Yul , Yun Kyong Sik , Lee Younki
Published: February 2020

The oxygen permeation flux of dual-phase doped ceria membranes, Ce0.9Gd0.1O2−δ–La0.7Sr0.3MnO3±δ (GDC/LSM), has been systematically studied as a function of their LSM content, thickness, and coating material. The percolation threshold of the composites for electronic conduction has been determined by general effective-medium theory. The minimum LSM content of the composite for electrical percolation was estimated to be ~20 vol%. The oxygen flux of uncoated fluorite phase-rich membrane exhibits a low oxygen flux under an air/He gradient, indicating that the permeation is mainly controlled by the surface-exchange kinetics of GDC. However, with modification of the surface on both sides, the flux of the membrane was substantially improved by about three orders of magnitude compared with that of the membrane with non-modified surfaces. This observation indicates that the surface modification of fluorite-rich dual phase membrane plays a crucial role in dramatically enhanced oxygen permeation flux. This significant enhancement of the oxygen fluxes is of particular importance as dual-phase membranes are the most studied class of the chemically and mechanically stable membrane. These promising results highlight the potential of dual-phase ceria/pure-electronic-phase membranes for industrial applications.
Electrochemical Reduction of UO2 to U in LiCl-KCl Molten Salt Eutectic Using the Fluidised Cathode Process
Authors: Abdulaziz Rema , Brown Leon D , Inman Douglas , Sharrad Clint , Shearing Paul R. , Brett Daniel J.L
Published: February 2020

The electrochemical reduction of UO2 to U metal using a fluidised cathode process [1] has been investigated. This has relevance for the pyroprocessing of mixed oxide spent fuel from certain types of nuclear power stations. Considering voltammetry alongside a predominance diagram for the system, the reaction path-way for both a fluidised cathode process and a packed metallic cavity electrode precursor was studied. The route the reduction process follows depends on pO2- and potential, which is highly influenced by the process used to reduce the metal oxide and its form.

The main reduction potential using the fluidised cathode appeared to be -2.2 V (vs. Ag/Ag+). Faradaic current efficiency was found to be ~ 92 %. The reduction process is split into three stages; the first where a seeding process takes place at a low potential to allow for the reduced uranium particles to be deposited onto the tungsten current collector; the second where rapid reduction of UO2 particles occurs with a growth in electrode size accompanied by an increase in current being passed; and the third where diminishing current is associated with reduction of the residual oxides in the melt takes place.

References:

[1] R. Abdulaziz, L.D. Brown, D. Inman, S. Simons, P.R. Shearing, D.J.L. Brett, Novel fluidised cathode approach for the electrochemical reduction of tungsten oxide in molten LiCl–KCl eutectic, Electrochemistry Communications, 41 (2014) 44-46.

Figure 1
Dynamic Impedance As a Cell Grading and Selection Method for the Lib Pack
Authors: Chung Jaesik
Published: February 2020

We have studied the Dynamic Impedance method as a cell grading and selection guideline for the multi-cell LiB module and battery pack. We have studied a) Cell Open Circuit (OCV), b) cell AC Impedance at 1 K Hz and c) cell initial capacity, which industries have been used for cell grading for the quality control and cell selection guideline for the multi-cell LiB pack. Full range of AC Impedance methode also has been studied for the same purpose.

We found the best condition of the Dynamic Impedance testing for the cell grading and selection guideline through with various variables of a) temperature, b) time, c) type of LiB and d) Capacity of the cell. We applied this technique to the multi-cell LiB modules by serial and parallel cell connections to verify the validation of this method and the impact of this technique.
Electrochemical Characteristics of Garnet-LLZO Materials Doping By Chemical Elements for All Solid Lithium Batteries
Authors: Yang Seung-Hoon , Kim Min-Young , Kim Da-Hye , Kim Kyeong-Joon , Choi Seung-Woo , Noh Tae-Hyoung , Kim Ho-Sung , Lee Moo Sung
Published: February 2020

Recently, many sorts of lithium batteries have been studied such as all solid and lithium-air batteries etc., for EV and ESS applications. Especially, all solid battery is one of the candidates for a large-sized battery in regard of the safety problem. Garnet-type LLZO electrolyte has good advantages with a high ionic conductivity and electrochemical potential window. However, it is reported that there are difficulties to prepare LLZO(Li7La3Zr2O12) pellets with high relative density. In this study, LLZO material was doped by the different elements of Al, Nb, Ta by co-precipitation process. Furthermore, we studied the effects of lithium excess concentration of Al-doped LLZO. We investigated not only the change of cubic and tetragonal structure but also electrochemical properties according to the synthesis conditions. As a result, ionic conductivity of Al-doped LLZO material was about 3x10-4 S/cm at room temperature, indicating a wide electrochemical window of 0~5.5V. Furthermore, we will introduce the electrochemical properties of unit cell using LLZO material in more detail.
Fabrication of All-Solid-State Batteries Using Li3BO3-Based Glass-Ceramic Electrolytes
Authors: Nagao Kenji , Hayashi Akitoshi , Tatsumisago Masahiro
Published: February 2020

Safety and reliability are important factors for rechargeable batteries with high energy density. All-solid-state batteries using inorganic solid electrolytes without leakage and flammability are one of the solutions for rechargeable energy sources. Sulfide electrolytes exhibit very high lithium ion conductivities around 10-4-10-2 S cm-1 at room temperature, which is comparable to that of organic liquid electrolytes[1]. In spite of such good conductivities, sulfide electrolytes are not stable under ambient atmosphere. On the other hand, oxide-based solid electrolytes are very attractive for application in all-solid-state batteries with safety because of their high chemical stability. In general, it is difficult to use oxide solid electrolytes in all-solid-state batteries because of poor deformability, which results in a huge interfacial resistance between electrolytes and electrodes. Oxide glass electrolytes with low melting properties such as Li3BO3 are promising materials for application in all-solid-state batteries. Li3BO3 glass showed the conductivity of 3.4×10-7 S cm-1 at room temperature. To enhance the conductivity of the Li3BO3 glass, we have prepared lithium ion conducting glasses based on Li3BO3 by rapid melt-quenching and mechanochemical techniques [2-4]. Especially, by heating 90Li3BO3·10Li2SO4 (mol%) glass, solid solution between high temperature phase of Li3BO3 and Li2SO4 were precipitated. This glass-ceramic showed a high lithium ion conductivity of 1.4×10-5 S cm-1 and good deformability. The 33Li3BO3·33Li2SO4·33Li2CO3 glass-ceramic electrolyte was prepared. It showed a relatively high conductivity of 2.3×10-6 S cm-1 and excellent deformability achieving relative density of 90% by cold-press, which is comparable to the deformability of sulfide electrolytes such as Li3PS4 glass [5].

 In this study, all-solid-state Indium / Li(Ni1/3Mn1/3Co1/3)O2 (NMC) cells using the 90Li3BO3·10Li2SO4 or 33Li3BO3·33Li2SO4·33Li2CO3 glass-ceramic electrolyte were fabricated. These cells operated as a secondary battery at 25-100oC. The first discharge capacity at 100oC of the cell using 90Li3BO3·10Li2SO4 glass-ceramic electrolyte was 100 mAh g-1, while the capacity using 33Li3BO3·33Li2SO4·33Li2CO3 glass-ceramic electrolyte was 150 mAh g-1. This capacity enhancement was caused by the better deformability of 33Li3BO3·33Li2SO4·33Li2CO3 electrolyte than that of 90Li3BO3·10Li2SO4 electrolyte.

References

[1] Y. Seino et al., Energy Environ. Sci., 7 (2014) 627.

[2] M. Tatsumisago et al., J. Ceram. Soc. Jpn., 95 (1987) 59.

[3] A. Hayashi et al., Phys. Chem. Glasses: Eur. J. Glass Sci. Technol. B, 54 (2013) 109.

[4] M. Tatsumisago et al., J. Power Sources, 270 (2014) 603.

[5] A. Sakuda et al., Sci. Rep., 3 (2012) 2261.
A Hydrate Melt Electrolyte for High Energy Density Aqueous Lithium-Ion Batteries
Authors: Yamada Yuki , Usui Kenji , Sodeyama Keitaro , Ko Seongjae , Tateyama Yoshitaka , Yamada Atsuo
Published: February 2020

Aqueous Li-ion batteries attract increasing attention as an ultimately safe rechargeable battery based on non-flammable and non-toxic aqueous electrolytes. However, their low operation voltage, limited by water’s electrochemical window (1.23 V), is a prime issue that has hindered their widespread applications. Here, by exploring optimized eutectic systems of several Li salts, we discovered a room-temperature hydrate melt of Li salts, in which all water molecules participate in Li+ hydration shells with retaining fluidity. As a new class of aqueous liquid electrolyte, a surprisingly wide 3.2 V stability window was achieved to unlock the water’s voltage limitation. Using the hydrate melt electrolyte, we observed, for the first time, the reversible reactions of Li4Ti5O12 and LiNi0.5Mn1.5O4 electrodes in an aqueous system (Fig. 1), both of which are far beyond the water’s stability window. As a proof of concept, we demonstrated charge-discharge cycling of a 3.1 V-class LiNi0.5Mn1.5O4/Li4Ti5O12 battery, as well as a 2.5 V-class LiCoO2/Li4Ti5O12 battery. We rationalized the unusual stability from the viewpoint of the unique liquid structure exclusively achieved in the hydrate melt state, on the basis of both experimental and theoretical approaches. We believe that our discovery of hydrate melt electrolytes will open an expanded research avenue for safe and high-voltage aqueous energy storage, breaking away from flammable, expensive, and toxic organic solvents.

Figure 1
Mechanistic Studies of Fluorinated Electrolyte for High Voltage Lithium-Ion Battery
Authors: He Meinan , Su Chi-Cheung , Wang Yan , Zhang Zhengcheng , Peebles Cameron
Published: February 2020

Lithium ion batteries have dominated the portable electronics market and have the potential to dominate large-scale battery applications including hybrid and electric vehicles as well as grid storage because of their high energy and power densities.[1] It is well known that conventional electrolytes (such as 1.2 M LiPF6 in EC/EMC 3/7) show poor anodic stabilities above 4.5 V versus Li/Li+.[2] However, high voltage electrolytes play an intrinsic role in many applications such as hybrid and electrical vehicles, aerospace uses and power grids. As a result, high voltage electrolytes are essential for the development of next generation lithium ion batteries. One possible solution is to develop fluorinated electrolytes which not only form kinetically stable SEI interphase, but also are resistant to oxidative decomposition due to their high oxidation potential. [3] In this work, a novel fluorinated electrolyte was introduced in a graphite-LiNi0.5Mn0.3Co0.2O2 full cell operated between 3.0 - 4.6 V. The electrolyte contains 1.0 M LiPF6 dissolved in a mixture of FEC and HFDEC solvent with 1wt % LiDFOB used as the additive. Compared to a conventional EC and EMC based electrolyte, the fluorinated electrolyte shows an excellent cycle life under a 4.6V cut off voltage. NMR and GC-MS were used to analyze the harvested electrolyte post-cycling while SEM, XPS and FTIR were employed to study the interface between the electrolyte and the bulk electrodes. Most importantly, HR-XRD and XANS were conducted to investigate and compare the cycled bulk cathode electrode in different electrolytes. To the best of our knowledge, the structural change of the cycled cathode material in different electrolytes has never been reported. Therefore, we believe this research is a crucial breakthrough for studying the interaction between the electrolyte and electrode. The methodology developed could be fundamental in the design and investigation of better electrolytes for next generation lithium ion batteries.

[1]Xu, Kang. "Nonaqueous liquid electrolytes for lithium-based rechargeable batteries." Chemical reviews 104.10 (2004): 4303-4418.

[2] Xu, Kang. "Electrolytes and interphases in Li-ion batteries and beyond." Chemical reviews 114.23 (2014): 11503-11618.

[3] Zhang, Zhengcheng, et al. "Fluorinated electrolytes for 5 V lithium-ion battery chemistry." Energy Environ. Sci. 6.6 (2013): 1806-1810.
Advanced Ceramic Li Ion Electrolytes for All-Solid-State Li Ion Batteries
Authors: Thangadurai Venkataraman
Published: February 2020

At present, the energy supply around the world comes from fossil fuels and is one of the main causes of greenhouse gas emissions. Attempts have been made to generate electricity using renewable sources, such as wind and solar, but it could be realized through the use of reliable electrochemical storage systems. Batteries can be used in combination with renewable energies to store energy when the demand is low and supply to the grid when demand is high. Among the known secondary batteries, Li ion batteries (LIBs) find applications ranging from small mobile electronics to transportation and even to stationary, grid storage systems. LIBs exhibit the highest power and energy densities over other known batteries. The most frequently used cathodes in LIBs include LiCoO2, LiNi1/3Mn2/3Co1/3O12 and LiFePO4 and graphite is the most popular choice for anode. Typical electrolyte used in the LIB consists of lithium salt (e.g., LiPF6, LiBF4 or LiClO4) dissolved in an organic carbonate such as ethylene carbonate, diethyl carbonate or propylene carbonate.

The current LIB research is mainly focused on improving the practical gravimetric and volumetric energy densities by developing advanced Li ion electrolytes and electrodes. Attempts have been made to replace unstable polymer members with high temperature stable and highly conducting ceramic Li ion electrolytes, including Li3N, Li-β-alumina, A-site deficient perovskite-type and garnet-type metal oxides. These solid electrolytes offer the advantages of being safe and compatible with advanced electrode materials, as well as a having a wide temperature range of operation and high Li ion conductivity. In this talk, recent advances in most promising garnet-type Li5La3M2O12 (M = Nb,Ta) oxides will be discussed. Since their discovery as Li ion conductors, there has been an increased interest in the development of garnet-type Li ion electrolytes for all solid-state LIBs. Some of the members of the garnet have been proven to be stable against chemical reaction with Li, as well as electrochemically stable up to 6 V vs. Li/Li+. These attributes, together with the good total Li ion conductivity, make them ideal electrolyte candidates for all solid-state LIBs.
Development of Novel High Energy Density Sn-Doped Sodium Layered Oxide Cathode Materials
Authors: Smith Katherine , Gruar Robert , Kendrick Emma
Published: February 2020

Sodium ion batteries are being developed as a  lower cost alternative to lithium ion batteries which find application in consumer electronics, power tools , stationary energy storage and electric vehicles. The lower cost of  sodium makes it an attractive technology r for application in stationary energy storage and other applications which require lower cost energy storage technologies. One of the limitations with sodium ion batteries for use in other applications is their low energy density.  Sharp laboratories of Europe Ltd (SLE) have been developing and optimising higher energy density cathodes for sodium ion batteries.

Several layered oxide systems have been reported as potential cathodes [i],[ii]  SLE has performed an optimisation of tin containing nickel based layered oxide materials which exhibit high specific capacities[iii]. In particular we have looked at the O3 type mixed nickel and manganese containing layered oxides of the formula  NaυNi1
v M2
w M3
xO2±6wherein Μ2 comprises tin, optionally in combination with one or more transition metals,  Μ3 comprises one or more transition metals. The incorporation of Sn is interesting because it leads to higher observed average voltages upon discharge, and exhibits higher specific capacities compared to other O3 type layered oxides with similar compositions. The main contribution to the higher average voltage upon discharge is the observation of a high voltage reversible plateaux.  An optimisation of the material composition has been performed which looks at the effect of the different dopants and dopant levels upon the observed voltage and specific capacity. Here we discuss the optimisation of the high energy sodium ion cathode material, and the origin of the voltage plateaus and the mechanism for charge and discharge mechanism for the Sn containing layered oxide materials.

[i] X. Li et al.  Electrochemistry Communications 49 (2014) 51–54

[ii] H. Yoshida, N. Yabuuchi and  S. Komaba Electrochem. Commun., 34 (2013), pp. 60–6

[iii] Kendrick, Gruar et al, Tin containing compounds, WO2015177568A1, 2015-11-26

Figure 1
Characteristics of All-Solid-State Thin-Film Battery Using Amorphous LixMyPOz Cathode Material
Authors: Shimizu Keisuke , Hayashi Saori , Sato Susumu , Nakayama Norikazu , Kusanagi Susumu , Nagamine Masayuki
Published: February 2020

A novel amorphous cathode material LixMyPOz for all-solid-state thin-film lithium-ion battery has been developed. Since a non-annealing process is employed, a thin-film lithium-ion battery can be fabricated by direct deposition of materials onto thin plastic film. LixMyPOz is formed through sputter deposition of Li3PO4 and metal or metal oxide targets. We have tested several metal elements (M = Ni, Mn, Co, Cu, Ag), and LiNiPO showed a high capacity of 330 mAh g−1 at 1C. In addition, a cell using this cathode material has demonstrated a high charge/discharge rate up to 30C.
Computational Modelling Study on Stability of Li-S/Se System
Authors: Masedi M. C. , Sithole H. M. , Ngoepe Phuti Esrom
Published: February 2020

Li-ion batteries have transformed portable electronics and will play a key role in the electrification of transport. However, the highest energy storage possible for Li-ion batteries is insufficient for the long-term needs of society. Here we consider a study on rechargeable lithium−sulfur (Li−S) batteries which hold great potential for high-performance energy storage systems because they have a high theoretical specific energy, low cost, and are eco-friendly.  This work employs computational modelling methods to explore stability, structural and electronic properties of discharge products formed in the Li-S/Se battery, especially Li2S/Se, which has potential to offer higher theoretical specific energy and remedies the challenges that Li-S battery encounters. First principle methods were used to calculate thermodynamic properties of Li2S and Li2Se, which agreed with available experimental results. A cluster expansion technique generated new stable phases of Li2S/Se system and Monte Carlo simulations determined concentration and temperature ranges in which the systems mix. Interatomic Born Meyer potential models for Li2S and Li2Se were derived and validated and used to explore high temperature structural and transport properties of Li2S/Se.
Storage and Effective Migration of Li-Ion for Defected Beta-LiFePO4 Phase Nanocrystals
Authors: Guo Hua , Song Xiaohe , Zheng Jiaxin , Pan Feng
Published: February 2020

Lithium iron phosphate, a widely used cathode material, crystallizes typically in olivine-type phase, α-LiFePO4 (αLFP). However, the new phase β-LiFePO4 (βLFP), which can be transformed from αLFP under high temperature and pressure, is originally almost electrochemically inactive with no capacity for Li-ion battery, because the Li-ions are stored in the tetrahedral [LiO4] with very high activation barrier for migration and the one-dimensional (1D) migration channels for Li-ion diffusion in αLFP disappear, while the Fe ions in the β-phase are oriented similar to the 1D arrangement instead. In this work, using experimental studies combined with density functional theory calculations, we demonstrate that βLFP can be activated with creation of effective paths of Li-ion migration by optimized disordering. Thus, the new phase of βLFP cathode achieved a capacity of 128 mAh g−1 at a rate of 0.1 C (1C = 170 mA g−1) with extraordinary cycling performance that 94.5% of the initial capacity retains after 1000 cycles at 1 C. The activation mechanism can be attributed to that the induced disorder (such as FeLiLiFe antisite defects, crystal distortion, and amorphous domains) creates new lithium migration passages, which free the captive stored lithium atoms and facilitate their intercalation/ deintercalation from the cathode. Such materials activated by disorder are promising candidate cathodes for lithium batteries, and the related mechanism of storage and effective migration of Li-ions also provides new clues for future design of disordered electrode materials with high capacity and high energy density.