bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Sodium Tin Sulfides As Electrolyte for Solid State Sodium Ion Batteries
Authors: McDaniel Malte , Xiong Shan , Wang Hai , Chen Hailong 
Published: February 2020

Safety concerns on conventional lithium ion batteries are attracting a lot of attentions from both academia and industry as the electric automobile market is fast growing. Replacing the organic, liquid, flammable electrolytes in conventional lithium ion batteries with inorganic, solid, nonflammable electrolytes can potentially eliminate the fire hazard of the batteries. However, currently the performance of all solid state lithium ion batteries are limited by a number of factors, including the low ionic conductivity and high interfacial resistance. On the other hand, low cost electrochemical energy storage technologies beyond lithium chemistry are also much desired for large scale applications.
In this work, we report the synthesis and electrochemical testing of several sodium tin sulfides as solid electrolyte for sodium ion batteries, aiming to combine the advantages in safety for solid state batteries and the low cost of the sodium chemistry. Na4SnS4 was synthesized by solid state reactions in pure phase. In situ XRD study on the synthesis process were used to reveal the formation mechanism of this compound. The Na ion conductivity of this compound at various temperatures was measured by using electrochemical impedance spectroscopy. The relationship between the conductivity and synthesis condition and starting materials are discussed. Full cells with using this compounds as the electrolyte were also fabricated with various methods and the electrochemical cycling performances of the cells were tested. The mechanical properties of the electrolyte and the full cells were also measured and discussed. Several other sulfides are also successfully synthesized in pure phase. Their conductivities were also measured and compared with Na4SnS4. These novel Na ion conductors provides new promise for developing high performance all solid state sodium ion batteries.
Figure caption: Figure 1. X-ray diffraction pattern of Na4SnS4 sample

Figure 1
Liquefied Gas Electrolytes for Electrochemical Energy Storage Devices
Authors: Rustomji Cyrus Sam , Yang Yangyuchen , Kim Taekyoung , Caldwell Elizabeth , Yoon Hyojung , Meng Ying Shirley 
Published: February 2020

Using electrolytes based on Liquefied Gas Solvents, high performance of both Li-Ion Batteries and Electrochemical Capacitors at temperatures as low as -60 °C has been demonstrated for the first time. Current Li-Ion technology necessitates the use of particular electrolyte solvents which are highly viscous and have relatively low electrolytic conductivity, preventing high performance below -20 °C. Further, Electrochemical Capacitors commonly use a toxic electrolyte for operation down to -40 °C. Using mild pressures to turn solvents which are typically gaseous at room temperature into a liquid phase, electrolytes with low melting points, low viscosities and moderate dielectric constants have been realized. A number of various solvent and salt systems have been characterized, some showing exceptionally high electrolytic conductivity over a very broad temperature range for both Li-Ion and Electrochemical Capacitor electrolytes. Novel mechanisms for the superior ionic conductivity in these solvents have been studied. Further, these solvents show a wide potential window of stability which may enable high voltage devices. We gratefully acknowledge funding from DOE ARPA-E (DE-AR0000646).
High-Rate Sodium Ion Batteries: Synergetic Effect of Robust Surface and Nano-Rod Primary Particles As Cathode Material for Sodium Ion Batteries
Authors: Hwang Jang-Yeon , Sun Yang-Kook 
Published: February 2020

Nowadays, to adjust the fluctuations in electricity production and efficient use of midnight off-peaks for stable energy supply, the mid-large scale battery system has been growing up [1]. In particularly, sodium ion batteries have many interests as an alternative candidate for cost-advantage versus lithium ion batteries because of large amounts of reservation of sodium resources in earth. However, intrinsic structural disadvantage of interstitial tetrahedral sites dissimilar to the O3 structure led to the low discharge capacity and cycle retentions and it have not yet satisfactorily addressed. Recently, to breakthrough present drawbacks, we suggested the new concept of radially aligned hierarchical columnar structure with varied chemical composition.
To further study of novel nano-structured with varied chemical composition materials, we carry out the synthesis and characterization of O3-type layered structure cathode material of constant concentration Na[Ni0.60Co0.15Mn0.25]O2 and full concentration gradient Na[Ni0.61Co0.12Mn0.27]O2 material. Through the comparison of electrochemical properties and related structural properties, herein, we investigated and defined the novel concept FCG materials.
Especially, we focus on the effect of particle morphology and micro structured properties by using micro scope technique. We believe that the unexplored site of radially assembled nano-rod structure primary particles having varied chemical composition is highly contribute to high power and high energy Na-ion battery systems.
References
[1] B. Scrosati, J. Hassoun, Y. K. Sun, Energy Environ. Sci. 2011, 4, 3287
[2] J.-Y. Hwang, S.-M. Oh, S.-T. Myung, K.-Y. Chung, I. Belharouak, Y.-K. Sun. Nat. Commun. 6 (2015) 6865.
Sodiation Kinetics of Metal Oxide Conversion Electrodes: A Comparative Study with Lithiation
Authors: He Kai , Lin Feng , Zhu Yizhou , Yu Xiqian , Li Jing , Lin Ruoqian , Nordlund Dennis , Weng Tsu-Chien , Richards Ryan M , Yang Xiao-Qing , Doeff Marca , Stach Eric A. , Mo Yifei , Xin Huolin L. , Su Dong 
Published: February 2020

The development of sodium ion batteries (NIBs) can provide an alternative solution to lithium ion batteries (LIBs) for sustainable, low-cost energy storage. Due to the many similarities between sodium and lithium chemistries, the development of sodium-ion batteries (NIBs) – in particular the discovery and development of electrode materials – has been benefited greatly from the knowledge developed in understanding lithium chemistries in LIBs. However, many electrode materials used in LIBs show an inferior performance in sodiation. For example, in transition metal oxides MOx (M = Fe, Co and Ni), the sodiation reactions have shown much lower capacity and slower kinetics than those commonly observed in lithiation reactions. This could not be simply interpreted from the difference in the ionic size of Na+ and Li+ because the reaction happened in this system is not intercalation but conversion. For the conversion compounds, although there were many papers published to investigate their electrochemical performance, the origin of different reaction kinetics is still not clear which hinder the further study on this system.
To address this issue, we present herein our comprehensive, systematic study of the sodiation and lithiation of a model MOx conversion compound, viz., nanostructured sheets of NiO. We investigate the sodiation and lithiation processes using a combination of multiple temporal- and spatial-scaled characterization techniques, including electrochemical measurements, in situ transmission electron microscopy (TEM), and ab initio molecular dynamics (MD) simulations. From the in situ TEM, where our previous results showing the lithiation heterogeneous reaction pathways, we found the sodiation only go through a “shrinking-core” pathway and further sodiation was blocked by a crystalline passivation layer of Na2O that formed at an early stage. Our MD simulation shows that the sodiation pathway originates from a layer-by-layer reaction that occurs during the insertion of Na ions; this was the rate-determining step for the entire process. In case of lithiation, however, the formation of Li anti-site defects significantly distorts the local NiO lattice, which thereby facilitates Li insertion and enhance the overall reaction rate. In conclusion, the intrinsic layer-by-layer sodiation reaction and the formation of a crystalline passivation layer of Na2O play an important role for sluggish sodiation reactions.
New Methods for Understanding Stacking Disorder in Honeycomb-Layered Batteries: Insights into Synthesis Mechanism and Influence on Electrochemical Performance
Authors: Khalifah Peter , Liu Jue , Bo Shou-Hang , Yin Liang , Ma Jeffrey , Wu Lijun , Bai Jianming , Zhu Yimei , Bak Seong-Min , Yu Xiqian , Yang Xiao-Qing , Grey Clare P. 
Published: February 2020

The layered alpha-NaFeO2 structure is one of the most important structural families for battery cathodes. In recent years, it has been found that a honeycomb-layered superstructure of the basic alpha-NaFeO2 structure type can produce enhanced specific capacities for Li-ion batteries (Li-excess compounds with Li2MnO3 motifs) and enhanced voltages for Na-ion batteries (compounds such as Na3Ni2SbO6 for which the entire discharge capacity is delivered above 3.0 V vs. Na+/Na). However, the crystallography of honeycomb-layered compounds is very complex, which results in the occurrence of both disordered and ordered polymorphs as well as complex long-range c-axis superstructures whose origin has not previously been determined. New tools for investigating, classifying, and quantifying the disordered in honeycomb-layered compounds have been developed and applied to Na-ion cathode materials with this structure type with an emphasis on the “number” faults associated with the position of the central atom of the honeycomb lattice rather than the “letter” faults associated with the layer position relative to the close-packed atom planes. This comprehensive work includes Rietveld refinements of synchrotron and neutron diffraction data, pair distribution function analysis, solid state NMR, TEM studies, and complementary electrochemical performance data. It is demonstrated that there is a continuous spectrum of compositions with varying amounts of number disorder. This number disorder is distinctly non-random, and the underlying thermodynamic reasons will be discussed, as well as the unusually slow reaction mechanism by which disorder is annealed out of the structure. Since the structure of honeycomb-layered compounds are strongly dependent on the synthesis history, the methods for quantifying the degree of disorder that will be presented are particularly important if systematic studies on this important class of materials are to be carried out. It is found that the degree of ordering has a clear impact on electrochemical performance, and thus control over sample disorder is required in order to attain the best cathode electrochemistry.
Rechargeable Zinc Batteries
Authors: Li Yun , Yang Jihui 
Published: February 2020

Keyword: Rechargeable Zinc batteries, spinel ZnMn2O4, electrochemical reaction mechanism
Rechargeable Zn batteries, consisting of abundant, environmentally benign electrode materials that can be manufactured economically and theoretically provide decent energy density (around 400 Wh/kg), are regarded as promising alternatives to lithium-ion batteries. Combined with a Zn metal anode and an aqueous ZnSO4 electrolyte, MnO2­ and the Prussian blue hexacyanoferrates have been shown to work as cathode materials for rechargeable Zn batteries. However, the significant capacity fade during long-term cycling tests and insufficient energy density largely hamper their applications. Meanwhile, there are ongoing debates on reaction mechanisms of the Zn/MnO2 system.
In this study, our goal is to investigate the possibility of spinel ZnMn2-xTMxO4 as cathode materials for rechargeable Zn batteries, verify the reaction mechanisms, and eventually to achieve high voltage. Single phase ZnMn2O4 nanopowders with good crystallinity were synthesized by a combination of co-precipitation reactions and subsequent calcination technique, and the synthesis parameters were systematically optimized. We found that the calcination temperature has a significant influence on the crystallinity and morphology, thus electrochemical behavior of ZnMn2O4 nanopowders. The optimized ZnMn2O4 with ZnSO4 as electrolytes shows an initial specific capacity of 125 mAh/g at C/10. To elucidate the electrochemical reaction mechanism of ZnMn2O4, phase & chemical compositions, and microstructure of cathodes before and after cycling were systematically investigated. In parallel, ZnMn2-xFexO4 (0≤x≤2) has been synthesized and characterized.
Capacity Contributing Conductive Cathode Additive for Sulfur Batteries
Authors: Sun Ke , Su Dong , Cama Christina A , DeMayo Rachel , Huang Jianping , Zhang Qing , Marschilok Amy C , Takeuchi Kenneth J , Takeuchi Esther S , Gan Hong 
Published: February 2020

The Lithium-Sulfur (Li-S) battery has been a subject of intensive research in recent years due to its potential to provide much higher energy density and lower cost than the current state-of-the-art lithium-ion battery technology. However, both cell reaction active materials, sulfur and Li2S, are electronically non-conductive, which leads to the low electrode utilization and fast capacity fade during cell cycling. Large amounts of non-active carbon host materials must be added to boost sulfur electrode electronic conductivity for high rate discharge, which lowers the sulfur electrode specific energy density.
Transition metal sulfides have been utilized as cathode material with high energy density and have been demonstrated to be rechargeable in lithium batteries. Many of these sulfides are electronic conductive with conductivity comparable to that of graphite and carbon black. Since they are also electrochemically active and can be cycled within the voltage window of sulfur battery, transition metal sulfides could be used as capacity contributing conductive cathode additive for sulfur batteries.
We have investigated Titanium Disulfide (TiS2), Pyrite (FeS2) and Cupric Sulfide (CuS) as capacity-contributing conductive cathode additives to the sulfur electrodes in Li-S battery. Sulfur electrodes containing the metal sulfide additives showed improved power capability under high rate discharge. While the cyclability of the hybrid electrodes vary widely depending on the type of conductive additive, different and unique electrochemical behaviors were observed for hybrid electrodes with TiS2, FeS2 and CuS respectively. Improved coin cell cycling performance was observed with TiS2 as the cathode additive at 1C discharge rate. The TiS2 distribution within the hybrid electrode showed significant impact on cell cycling capacity fade. The mechanisms associated with the electrochemical performance of each chemical system are discussed.
High Capacity Li-S Secondary Battery Using Vertically-Aligned CNT Electrode
Authors: Fukuda Yoshiaki , Nozue Tatsuhiro , Nakano Haruhisa , Tsukahara Naoki , Murakami Hirohiko , Omoda Ryo , Yamada Takanobu , Ito Seitaro , Aihara Yuichi 
Published: February 2020

In recent years, the lithium-sulfur (Li-S) secondary battery has been energetically researched worldwide as a good candidate for next-generation secondary batteries. The sulfur active material has a theoretical capacity of 1675 mAh g-1and is abundant and highly inexpensive. However, several issues are associated with the use of Li-S secondary batteries, such as low utilization due to the insulating property of sulfur and the redox shuttle phenomenon caused by the dissolution of polysulfides generated during the discharge process.
In the present work, we have developed a Li-S secondary battery using the carbon nanotube (CNT) technoloy. Multiwalled-CNTs were directly grown on a nickel current collector by using the thermal chemical vapor deposition (CVD) method. The CNT films were used as the electrode for the Li-S battery. The S-CNT cathode was fabricated by impregnating it with molten sulfur. Then, sulfur powder was uniformly placed on the CNT film and heated at more than the melting point of 113°C. Our CNT has a diameter of 10-15 nm and a length of 200-600 µm. Therefore, the CNT electrode has a wide reaction area owing to its large specific surface area. In addition, the active materials can react rapidly because the electrons quickly access through the CNTs that connect directly with the current collector.
At IMLB 2014, we reported that coin-cell-type Li-S batteries with a sulfur loading of up to 10 mg cm-2 operate at a current density of 0.5 mA cm-2 [1]. However, more sulfur loading is required, in order to achieve the electrode capacity of 300 Wh kg-1 for practical usage. As sulfur loading increased to more than 10 mg cm-2, the discharge capacity decreased dramatically, probably owing to be attributed to inhomogeneous sulfur distribution in the CNT film. Moreover, the CNT films fell off the nickel current collector because of the shrinkage of the CNT bundles owing to the absorption of sulfur. Therefore, we attempted to synthesize harder CNT films with homogeneously impregnated sulfur. A thick amorphous carbon layer was coated on the CNTs by optimizing the thermal CVD process, thus making the CNT films harder. Moreover, the adhesiveness between the CNTs and the nickel current collector was enhanced, which improved CNT exfoliation. For homogeneous distribution, sulfur impregnation was performed in vacuum. The sulfur was considered to spread over the CNT films more uniformly. We could obtain the stable coin-cell-battery performance with sulfur loading of up to 20 mg cm-2, and the capacity was estimated to be more than 300 Wh kg-1 [2]. We manufactured 1 Ah-class pouch cell, with electrode surface area of 50 cm2.
Reference
[1] N.Tsukahara, presented at The 17thInternational Meeting on Lithium Batteries, Como, 2014 (unpublished)
[2] T. Yamada, presented at The 56th Battery Symposium, Nagoya, 2015 (unpublished)

Figure 1
Redox Flow Lithium-Oxygen Battery with Unprecedently Low Charging Overpotentials
Authors: Zhu Yun Guang , Jia Chuankun , Wang Xingzhu , Yang Jing , Wang Qing 
Published: February 2020

Lithium oxygen battery (LOB), as a promising next generation energy storage system, has attracted tremendous attention. However, for aprotic systems due to the deposition of insoluble and insulating discharging product Li2O2, surface passivation and pore clogging of the cathode occur. As a result, the charging overpotential of LOB is generally intolerably high. While people have tried to use homogeneous catalysts — redox mediators dissolved in the electrolyte to address the above issues, the passivation and clogging problems remain especially at deep discharge. Inspired by the redox targeting concept in redox flow lithium battery, we have recently proposed a new battery concept — redox flow lithium oxygen battery (RFLOB), which elegantly resolves the surface passivation and pore clogging issues.1-3 As shown in Figure 1, with a pair of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) redox catalysts, the formation of Li2O2 during discharge and oxidation during charge could be performed in a separate gas diffusion tank rather than on the cathode in the cell. Therefore, the passivation and clogging problems of the electrode are feasibly obviated.4 Here, we will report a series of robust redox mediators as efficient ORR and OER catalysts in the RFLOB system. By optimizing the electrolyte compositions, extremely low charging overpotential (~0.20 V) has been achieved, which results of unprecedently high voltage efficiency. The underlying mechanism of the redox catalytic processes toward ORR and OER will be discussed in detail. We anticipate RFLOB provide a new vista to the development of Li-air battery with high round-trip efficiency for practical applications.
Figure 1. The structure of a redox flow lithium oxygen battery.

Reference:

(1) Wang, Q.; Zakeeruddin, S. M.; Wang, D.; Exnar, I.; Grätzel, M. Angewandte Chemie International Edition
2006, 45, 8197.
(2) Huang, Q.; Li, H.; Gratzel, M.; Wang, Q. Physical Chemistry Chemical Physics
2013, 15, 1793.
(3) Pan, F.; Yang, J.; Huang, Q.; Wang, X.; Huang, H.; Wang, Q. Advanced Energy Materials
2014, 4, n/a.
(4) Zhu, Y. G.; Jia, C.; Yang, J.; Pan, F.; Huang, Q.; Wang, Q. Chemical Communications
2015.

Figure 1
Cluster-Based Reduced-Order Modeling of Lithium-Ion Battery
Authors: Esfahanian Vahid , Shahbazi Ali Akbar 
Published: February 2020

The Lithium-ion batteries are certainly the battery of choice today because of their high voltage platform, low maintenance, high energy and power density, good cycle performance, and low self-discharge. Developments in lithium-ion battery technology make them inexpensive, small and extremely light-weight. These batteries are capable of providing the great power needs of today’s high-tech industries, ranging from small portable devices, e.g. smart phones, to full/hybrid electric vehicles and also alternative energy storage requirements of renewable power generation. The lithium-ion battery performance plays a significant role in the system energy management. As a consequence, battery real-time monitoring and accurate state-of-charge (SOC) estimation are necessary. However, full order electrochemical models are not suitable for this purpose due to high computational cost. Reduced order model (ROM) is one of the promising models which is computationally cost effective while ensuring accurate results. Using data clustering are one of attractive ways to make reduced order model. The capability of cluster-based reduced order modeling (CROM) has been proven in fluid mechanics engineering fields. This approach, starts with a snapshot data set. The observations are clustered based on their similarity and then the means of these clusters (centroids) are used to constitute the reduced order basis.
In the present study, cluster-based reduced order modeling is applied to electrochemical transport governing equations in order to simulate a lithium-ion battery. For this purpose, the governing equations including conservation of species and charge are solved all together using finite volume method (FVM) by which the snapshot data are provided. The data are clustered by k-means clustering algorithm in order to obtain the centroids which are optimal low-dimensional basis for representing an ensemble of high-dimensional simulation data. This low-dimensional basis are used to formulate reduced order models of complex fields of battery. The obtained numerical results show that not only the CROM of lithium-ion battery significantly decreases the computational time but also there is an excellent agreement with the results of computational fluid dynamics (CFD) models, consequently is suitable for deployment in real-time monitoring and battery management systems.