bluuebunny/crossref_metadata_2025 huggingface dataset:
Quinone-Based Flow Battery with Increased Open Circuit Voltage
Authors: Gerhardt Michael R. , Marshak Michael P. , Huskinson Brian , Gordon Roy G. , Aziz Michael J.
Published: February 2020

Quinone-based flow batteries exhibit rapid redox kinetics, contain no electrocatalyst and use very inexpensive redox active materials [1]. Consequently, they appear to be very attractive candidates for inexpensive, large-scale electrical energy storage. We compare the performance of several substituted quinone/hydroquinone redox couples in an aqueous flow battery. We show that various substitutional groups can alter the electrochemical properties of the quinone, which in turn affects the performance of the flow battery. One substituted quinone at the negative electrode, when combined with Br2/HBr at the positive electrode, exhibits an open circuit voltage exceeding 1.0 V and a peak galvanic power density exceeding 0.24 W/cm2when fully charged.

Fig. 1. Polarization plot (a) and galvanic power densities (b) of a substituted quinone-bromine flow battery at various states of charge (SOC). The electrodes are Toray carbon paper with no electrocatalyst. The membrane is Nafion 212. The negative side is 0.5 M substituted quinone in 1 M sulfuric acid. The positive electrode is 1.5 M hydrobromic acid, 0.25 M bromine.
Membrane and Electrode Effects in the Br2 – H2 Redox Flow Cell
Authors: Tucker Michael C , Srinivasan Venkat , Battaglia Vince , Cho Kyu Taek , Weber Adam Z. , Lin Guangyu , Chong Pau Ying , Nguyen Trung Van
Published: February 2020

The bromine - hydrogen flow cell under development at Berkeley Lab provides high power density and stable long-term cycling. During discharge, Br2 in HBr (aq) is fed to the cathode compartment where bromine is reduced to bromide, generating the theoretical open circuit potential of 1.098 V at 25°C. On charge, H2 and Br2 are generated from HBr at the (-) and (+) electrodes, respectively. The challenges include: high vapor pressure of bromine gas; migration of water and bromine to the hydrogen anode during charging; poisoning of the anode Pt catalyst by bromine; and, formation of mixed aqueous and liquid bromine phases at high states of charge (SOC).

Peak power of 1.4W/cm2 and >90% efficiency at 0.4W/cm2 were reported previously [1]. Cycling with 3M HBr electrolyte and closed anode tank (hydrogen stored in system) yielded Coulombic efficiency above 95% and energy efficiency around 80% as shown in Figure 1. Initial capacity fade was observed over the first 20 cycles, after which the capacity was stable indicating minimal loss of bromine from the system.

Cell materials selection and architecture has a large impact on cell performance. Upon discharge, limiting current behavior arises from liquid flooding in the anode reducing gas transport, as seen in Figure 2. Printing the anode catalyst layer directly on the membrane (red line) improves the performance and limiting current compared to printing it on the GDL before cell assembly (black line). Presumably this is due to improved contact at the membrane/anode interface, resulting in lower interfacial impedance for proton transport and eliminating liquid pooling between the membrane and anode.

The performance can be significantly improved by pre-boiling the membrane-anode assembly (blue line). Boiling increases transport properties, and the improved performance can be attributed to increased proton conductivity in the membrane and anode CL. Water transport and bromine crossover are also increased, however. The crossover bromine and water must be returned to the cathode to maintain concentrations in the electrolyte solution, increasing system complexity. Bromine crossover and reduction at the anode results in self-discharge, which lowers coulombic efficiency. Boiled NR212 membrane displays a high self-discharge current of 13 mA/cm2, compared to <2mA/cm2 for the as-received membrane.

The impact of these effects on system performance and efficiency during charge-discharge cycling will be discussed.

References

[1] Cho KT, Albertus P, Battaglia V, Kojic A, Srinivasan V, and Weber AZ, Energy Technol. 2013, 1, 596 – 608.

Acknowledgements

This work was funded by Advanced Research Projects Agency-Energy (ARPA-E) of the U. S. Department of Energy under contract number DE-AC02-05CH11231 with cost share provided by Robert Bosch Corp and Award No. DE-AR0000262 to TVN Systems, Inc.
Effect of Morphology and Size of Nickel Particles on Electrochemical Performance of Sodium Metal Chloride Rechargeable Battery
Authors: Choi Joon-Hwan , Park Min-Jung
Published: February 2020

Because of the limitation of lithium resources, sodium-based rechargeable batteries started to emerge as potential candidates for medium and large-scale stationary energy storage system (ESS) again. Na-S batteries have been used for large-scale stationary ESS but intrinsically have a risk for explosion. Sodium metal chloride batteries based on Na-NiCl2 chemistry, however, are consisted of safer electrode configuration with nickel, NaCl and NaAlCl4 as cathode ingredients than the Na-S batteries. The Na-NiCl2 batteries offer many attractive properties such as high cell voltage, high theoretical specific energy, and broad range in operating temperature. The nickel chloride electrode plays an important role in the cell performance. A qualitative and quantitative understanding of the electrochemical and morphological properties of NiCl2, therefore, is very important. This paper will describe effect of morphology and size of nickel particles on electrochemical performance of the sodium metal chloride batteries including synthesized nickel powders having very high porosity.
Optimization of Energy Storage System Considering Battery Degradation
Authors: KIM Sojin , Kwon Kyoon , PARK Hayan
Published: February 2020

Energy storage system(ESS) is operated to save and release electric energy. And the battery in an ESS performs an essential function. For this purpose its capacity needs to be finely optimized for specific applications(peak shaving, frequency control, arbitrage, UPS etc).

Some papers have already showed the studies about the topic of optimization of battery capacity in an ESS, but a battery degradation factor and irregular operation event have not much been considered. Actually, ESS may experience a very irregular operational event and the decrease of battery capacity during repeated charge/discharge is a major issue to be addressed. In the ESS industry, usually several factors such as state of charge, time, temperature, and C-rate interdependently affect the decrease of battery capacity in a complicated mode. In order to install the ESS in a specific application looking for a reasonable benefit and a sufficent realiability, ESS lifetime prediction technique considering degradation of battery is highly required.

In this study, the battery capacity fading through test of dynamic stress factors was quantifized and reflected to designing of ESS battery. The goal is to make an accurate estimating methodology of ESS lifetime and benefit from its installation in specific applications.
Development of a Planar Sodium Sulfur Cell
Authors: Jung Keeyoung , Park Yoon-Cheol , Park Sun-Hong , Lee Changhui , Cho Munkyu , Kim Goun , Lee Younki , Lee Ju Hyeok , Cheon Sung Wun , Hwang Soon Cheol , Yang Choongmo
Published: February 2020

A noble prototype planar sodium sulfur (NaS) cell with a self-standing type cell design has been developed for high power energy storage systems (ESS) applications. Upon designing the cell, a thermal stress analysis combined with a finite element method (FEM) has been conducted in order to (1) maximize the volumetric energy density of a multiple cell stack or module and to (2) predict the maximum stress accumulation and mitigate the maximum local stresses during freeze/thaw cycles. The analysis is of great importance in designing the high temperature sodium batteries since the thermal stresses at the joints become larger as the cell size increases, and to avoid the cell failure the thermal stress should be sufficiently smaller than the bonding strength at the heterogeneous joints. Based on the study, a number of cell designs with different shapes and sizes have been created, and in succession, a couple of cells were successfully materialized out of selected designs using various state-of-art joining technologies, such as electron beam welding (EBW), thermal compression bonding (TCB), and glass sealing for metal-metal, metal-ceramic, and ceramic-ceramic joints, respectively. Finally, the cell characteristics of assorted cells will be discussed.
Development of Intermediate Temperature Sodium-Metal Halide Battery
Authors: Kim Jin Yong , Li Guosheng , Lu Xiaochuan , Meinhardt Kerry , Sprenkle Vincent
Published: February 2020

The sodium-metal halide battery has gained increasing interests as a large-scale energy storage device for renewable energy applications due to high specific energy and power density. They exhibit several advantages over the conventional sodium-sulfur (NaS) battery, which include higher voltage, safe cell failure mode, and easiness of assembly in discharged state. A major obstacle in commercialization of sodium-metal halide battery is relatively high cost compared to the NaS battery. Our research at PNNL has focused on lowering the cost of the sodium-metal halide battery by decreasing the operating temperature less than 200°C. In this intermediate temperature range, low-cost high throughput manufacturing process can be applied using economical polymer seals and metal cases. Another effort has been geared towards replacing expensive Ni with economical active materials such Zn and Fe. In this presentation, our progress in the development of IT sodium-metal halide battery will be discussed in detail.
Metal Oxide Nanoarrays Grown on Metal Substrates As Binder-Free Anodes for Li Ion Batteries with Excellent Rate Capability
Authors: Chen Shuai , Xin Yuelong , Zhou Henghui , Qi Limin
Published: February 2020

Abstract not Available.
Raman Spectroscopy on Zero-Strain Lithium Insertion Material Li[Li1/3Ti5/3]O4 during Change and Discharge Reaction
Authors: Mukai Kazuhiko , Kato Yuichi , Nakano Hideyuki
Published: February 2020

Abstract not Available.
Correlation Between the Particle Size and Morphology and the Electrochemistry of Monoclinic Li3V2(PO4)3 Cathode Materials
Authors: Lueangchaichaweng Warunee , Gaberscek Miran
Published: February 2020

Abstract not Available.
Multi-Scaled Porous Nitrogen-Doped Carbon Xerogels for High-Performance Anode Materials in Lithium-Ion Batteries
Authors: Liu Hao , Liu Xichuan
Published: February 2020

Abstract not Available.
Free-Standing One-Dimensional Coaxial Nanostructured Electrodes for Electrochemical Energy Storage
Authors: Fu Huo Kai , Paul Chu K
Published: February 2020

Abstract not Available.
Nanochannel Modulated Light-Powered Bio-Capacitor
Authors: Rao Siyuan , Xiang Yan
Published: February 2020

Abstract not Available.
Synthesis and Electrochemical Properties of Li3V2(PO4)3/Graphene Composites
Authors: Jin Bong-Soo , Choi Mansoo , Kim Hyun-Soo
Published: February 2020

Abstract not Available.
Synthesis of Carbon Incorporated Li2MnSiO4 Cathode Materials Using Planetary Ball-Milling and Their Electrochemical Properties for Li-Ion Batteries
Authors: Sun Ho-Jung , Han Jin-Gu , Park Gyungse , Shim Joongpyo
Published: February 2020

Abstract not Available.
Electrochemical Fabrication of Novel MnO2-Poly(5-cyanoindole) Composite and Its Application for Supercapacitors
Authors: Zhou Weiqiang , Xu Jingkun , Jiang Fengxing
Published: February 2020

Abstract not Available.
Volume Properties of the Electrolyte of the All Vanadium Redox Flow Battery.II. the System of VOSO4+ H2so4+ H2o at 298.15
Authors: Xu Wei-Guo , Qin Ye , Liu Jianguo , Yan Chuanwei
Published: February 2020

Abstract not Available.
Preparation and electrochemical properties of V3O7·H2o/graphene nanocomposite for rechargeable lithium battery
Authors: Zhu Kai , Wang Chunzhong , Wei Yingjin , Chen Gang
Published: February 2020

Abstract not Available.
Electrochemical Properties of P2-Na2/3[Ni1/3Mn2/3]O2 Cathode Material for Sodium Ion Batteries
Authors: Wang Hong , Liao Xiao-Zhen , Ma Zi-Feng , He Yu-Shi
Published: February 2020

Abstract not Available.
In-Situ Synthesis of 3D-Graphene Network Embedded Tin Nanoparticles as Superior Lithium Ion Battery Anode
Authors: He Chunnian , Qin Jian
Published: February 2020

Abstract not Available.
Organic Conjugated Carbonyl Compounds As Cathode Materials for Rechargeable Lithium Ion Batteries
Authors: Li Hao , Wang Shiwen , Liang Yanliang , Huang Weiwei , Zhu Zhiqiang , Liang Jing , Chen Jun
Published: February 2020

Abstract not Available.
ANODE Performance of Lithium-Silicon ALLOY Prepared By Mechanical Alloying for Use in ALL-SOLID-State Lithium Secondary Batteries
Authors: Park Hye Won , Song Jung-Hoon , Choi Heekyu , Jin Joo Sung , Lim Hyung-Tae
Published: February 2020

Abstract not Available.
One-Step Electrodeposition of Poly(indole-7-carboxylic acid) Nanowires and Their High Capacitance Properties
Authors: Ma Xiumei , Zhou Weiqiang , Jiang Fengxing , Xu Jingkun
Published: February 2020

Abstract not Available.
Electrochemical Synthesis and Capacitance Properties of a Novel Poly (3,4-ethylenedioxythiophene) Derivative-Based Electrode Material
Authors: Mo Daize , Zhou Weiqiang , Ma Xiumei , Xu Jingkun , Lu Baoyang , Jiang Fengxing
Published: February 2020

Abstract not Available.
Open Framework Fluorides As Insertion/Conversion Cathodes for Li and Na Batteries
Authors: Li Chilin
Published: February 2020

Abstract not Available.
Electrostatic Spray Deposition of Additive-Free TiO2-VO2 Thin Films with Enhanced Electrochemical Capacity
Authors: Hu Chenchen , Hu Xianluo , Huang Yunhui
Published: February 2020

Abstract not Available.
Polyimide As anode Electrode Material for Rechargeable Sodium Batteries
Authors: Chen Long , Wang Yong-Gang , Xia Yong-Yao
Published: February 2020

Abstract not Available.
Flexible and Wire-Shaped Micro-Supercapacitor Based on Ni(OH)2-Nanowire and Ordered Mesoporous Carbon Electrodes
Authors: Dong Xiao-Li , Wang Yong-Gang , Xia Yong-Yao
Published: February 2020

Abstract not Available.
High-Temperature Ceramic Separator Composite for Lithium-Ion Battery
Authors: Zhou Yin Jian
Published: February 2020

Abstract not Available.
Effect of Lithium Content on LiMnPO4 and Its Electrochemical Property for Lithium Ion Batteries
Authors: Xu Huayun , Jiang Xiaolei , Wang Nana , Zhou Yanli , Yang Jian , Qian Yitai
Published: February 2020

Abstract not Available.
Polymer-Decorated Mesoporous Carbon for Encapsulating Sulfur As Cathode Material in Lithium Sulfur Batteries
Authors: Zhao Xiaohui , Manuel James , Ahn Jou-Hyeon
Published: February 2020

Abstract not Available.
Tuning the Shape and Surface Structure of Pt Nanocrystals: From Tetrahexahedron to Hexoctahedron and to Trapezohedron
Authors: Tian Na , Zhou Zhi-You , Sun Shi-Gang
Published: February 2020

Abstract not Available.
Influence of Molecular Weight of Gelatin on Electrochemical Performance of the Sulfur Cathode
Authors: Huang Yaqin , Chen Yilei , Xiong Xing , Gao Mengyao , Wang Weikun , Zhang Hao
Published: February 2020

Abstract not Available.
Nitrogen-Doped Double-Shelled Hollow Nanocarbon Spheres with a Three-Dimensional Hierarchically Porous Structure for Supercaparcitor Applications
Authors: Xing Wei
Published: February 2020

Abstract not Available.
One-Pot Synthesis of Tin-Embedded Carbon/Silica Nanocomposites for Anode Materials in Lithium-Ion Batteries
Authors: Hwang Jongkook , Lee Jinwoo
Published: February 2020

Abstract not Available.
Aqueous Lithium-Iodine Battery
Authors: Byon Hye Ryung , Zhao Yu
Published: February 2020

Abstract not Available.
Fluorinated Electrolytes for 5 V Li-Ion Chemistry
Authors: Hu Libo , Xue Zheng , Azimi Nasim , Zhang Zhengcheng
Published: February 2020

Abstract not Available.
Study of Li3VO4 As a Promising Insertion Anode Material for Lithium-Ion Batteries
Authors: Li Huiqiao
Published: February 2020

Abstract not Available.
Effect of heat treatment on the structure and electrochemical performance of FePO4 coated spinel LiMn2O4
Authors: Shang Yesheng , Huang Tao , Yu Aishui
Published: February 2020

Abstract not Available.
The Application of FeS2-Based Cathode Materials in Thermal Battery
Authors: Zhao Xiaoling , Liu Bo
Published: February 2020

Abstract not Available.
Nanostructured MnO2-Based Materials As Promising Electrodes for Supercapacitors
Authors: Xia Hui , Lu Li , Zhu Dongdong , Li Bo
Published: February 2020

Abstract not Available.
Preparation of Graphene/Carbon Nanotube Film over Copper Foil As Anode for Lithium Ion Batteries
Authors: Dong L , Feng Jian min , Han Yan , Dong Li tian , Li Dejun
Published: February 2020

Abstract not Available.
Galvanostatical Performance of Rice-Carbon-Coated Silica As Anode for Lithium Ion Batteries
Authors: Lin Mingtong , Yang Won-Geun , Hong Jung-Eui , Oh Rye-Gyeong , Ryu Kwang-Sun
Published: February 2020

Abstract not Available.
Polypyrrole/Manganese Oxide Hybrid Coaxial Arrays for High-Performance Li-O2 Battery
Authors: Gao Qiuming , Li Zeyu , Liu Zhengping
Published: February 2020

Abstract not Available.
A Study on Structures and Electrochemical Lithium/Sodium Insertion Mechanisms for Hard Carbon Negative Electrodes
Authors: Dahbi Mouad
Published: February 2020

Abstract not Available.
Atomic-Scale Structure of Intercalated/De-Intercalated Electrode Materials in Lithium/Sodium Ion Batteries
Authors: Gu Lin , Hu Yong-Sheng , Guo Yu-Guo , Huang Xuejie , Li Hong , Chen Liquan
Published: February 2020

Abstract not Available.
Invited Presentation: High-Performance Self-Humidifying Bipolar Membrane Fuel Cell with Unique Water Transport Property
Authors: Xiang Yan , Peng Sikan , Xu Xin , Sui Pang-Chieh , Lu Shanfu , Djilali Ned
Published: February 2020

Abstract not Available.
Space-Confinement-Induced Synthesis of Planar Nitrogen-Doped Graphene for Catalysis of Oxygen Reduction
Authors: Wei Zidong , Ding Wei , Wan Li-Jun
Published: February 2020

Abstract not Available.
Bimorph Electrochemical Actuator Based on Graphene Nanosheet/Carbon Nanotube/Ionic Liquid
Authors: Randriamahazaka Hyacinthe
Published: February 2020

Abstract not Available.
Effect of PVDF Film Structure on the Piezoelectric Property
Authors: Oh Eunseok , Lim Sangwoo
Published: February 2020

Abstract not Available.
Surface Morphology Effect on Electroreduction of CO2
on Cu Nanostructure Electrode
Authors: Qiao Jinli , Liu Yuyu
Published: February 2020

Abstract not Available.
Stability of Graphene-Supported DMFC Cathode Catalysts
Authors: Wang Xindong , Lu Lixin , Wang Meng , Zheng Le
Published: February 2020

Abstract not Available.
Ethanol Electro-Oxidation in an Alkaline Medium Using the Nanostructured Platinum-Nickel Electrocatalysts
Authors: Tamasauskaite-Tamasiunaite Loreta , Balciunaite Aldona , Zabielaite Ausrine , Vaiciuniene Jurate , Juskenas Remigijus , Norkus Eugenijus
Published: February 2020

Abstract not Available.
Enhanced Photoelectrochemical Properties with Doped TiO2 for Solar Energy Conversion
Authors: Cui Xiaoli
Published: February 2020

Abstract not Available.
Keynote Presentation: Plasmonic Photoelectrochemical Cells and Photocatalysts for Solar Fuel Productio
Authors: Wu Nick
Published: February 2020

Abstract not Available.
TiO2 Nanotube Array Based Photoelectrochemical Water Splitting
Authors: Wang Peng , Zhang Zhonghai
Published: February 2020

Abstract not Available.
Comments on the Effect of Concentration Polarization on the Performance of Fuel Cell
Authors: Reda Mahmoud R.
Published: February 2020

Abstract not Available.
An Electrochemical Model Considering the Electric Double Layer of Nano-Size Materials for Lithium Ion Battery
Authors: Jia Ming , Cheng Yun , Du Shuanglong , Tang Yiwei , Li Jie
Published: February 2020

Abstract not Available.
Smoothing out NaxCo0.7Mn0.3O2 ocv Curve – Role of the Oxygen Nonstoichiometry
Authors: Molenda Janina , Baster Dominika
Published: February 2020

It is well known that NaxCoO2-y exhibits complicated character of the OCV (Open Circuit Voltage) curve, with several potential plateaus and jumps in 2.0-3.8 V range [1,2]. Origin of such the behavior is commonly attributed to the Na cations ordering [3]. However, often neglected influence of the electronic structure of the cathode material, which manifest itself as an additional energy states present in the main energy gap, seems to play a major role in this case. These states can be directly related to the presence of the oxygen vacancies [4].

In this work we show a novel approach, based on the consideration of the influence of cation dopants replacing partially cobalt, which aims to smooth out the OCV characteristic of Na/Na+/NaxCoO2-y battery. On a basis of work [4], one can state that in order to remove most of the potential jumps, the material has to be oxygen stoichiometric (NaxCo0.7Mn0.3O2) and no sodium ordering should be present. Since +4 oxidation state for cobalt cations is not the most favourable one, it gives rise to a presence of the oxygen vacancies, which decrease the average oxidation state of Co. If an appropriate dopant with stable +4 state would be introduced in cobalt positions, the concentration of the oxygen vacancies shall decrease considerable. Furthermore, random distribution of such dopant in Co sublattice will diminish the tendency of Na cations to form ordered structure.

As predicted from the considerations shown above, in the case of Mn substitution, OCV curve of Na/Na+/NaxCo0.7Mn0.3O2 is almost completely smoothed out, with only one major potential jump, which is associated with x = 0.5 mol·mol-1. Apart from basic scientific aspect, the obtained result is interesting from the point of view of application, as in commercial batteries voltage cannot show any non-monotonous behaviour.

References:

[1] R. Berthelot, D. Carlier and C. Delmas, Nature Materials 10 (2011) 74.

[2] J. Molenda, C. Delmas and P. Hagenmuller, Solid State Ionics, 9-10 (1983) 431.

[3] Y. Meng, Y. Hinuma, G. Ceder, J. Chem. Phys. 128 (2008) 1047081.

[4] D. Baster, K. Dybko, M. Szot, K. Świerczek and J. Molenda, Solid State Ionics (2013) http://dx.doi.org/10.1016/j.ssi.2013.11.

Acknowledgements: The project was funded by the National Science Centre Poland (NCN) on the basis of the decision number DEC-2011/02/A/ST5/00447.
A Synergistic Approach to Reduce the Hysteresis in Conversion Reactions
Authors: Bernuy-López Carlos , Pérez-Villar Sofía , Galceran Montserrat , Muñoz Márquez Miguel Ángel , Casas-Cabanas Montserrat
Published: February 2020

Keywords:Lithium-ion battery, conversion reaction, hysteresis, composite material

In order to expand the Li-ion battery (LIB) technology and to enlarge energy demanded applications such as the electrical vehicle, an increase in their energy storage density is needed. An alternative to common intercalation materials are the so-called conversion materials which undergo a multi-electron redox process [1]. Instead of inserting Li, these materials undergo reversible reduction to form metal nanoparticles M0 and binary Li compounds: Mn+Xy + nLi++ ne- ↔ M0 + yLiz/yX [2]. Transition metal oxides such as Fe2O3 or Fe3O4are examples of this type of materials and have largely been studied these last years due to their high capacity values, good cycleability, capacity retentions and low toxicity and cost [2]. However, they present some drawbacks such as large voltage hysteresis between charge and discharge, which would lead to an enormous loss of energy efficiency of the battery.

In this work we present a synergistic approach to reduce the hysteresis in conversion materials. To do so, C- FeOxcomposites with tailored microstructure are prepared using low cost methods. In the literature, carbon-metal oxide nanocomposites has already been used as a strategy to improve the cycleablity of conversion materials but no hysteresis reduction effect was previously observed [2, 3]. In our work, a significant hysteresis voltage reduction ( ≥ 0.3 V) will be shown through the combination of two materials reacting through different mechanisms (intercalation and conversion). The reduction of polarisation through a dual mechanism has been observed in the nanocomposite formed during the electrochemical reaction of titanium hydroxyfluoride [4] and is herein applied to abundant and low cost materials able to deliver much higher capacities. Insights about the electrochemical reactions and mechanisms taking place in these composite materials will be shown by means of TEM, XPS and in-situ Raman spectroscopy data.

References

[1] Armand, M.; Tarascon, J.-M. Nature 2008, 451, 652.

[2] Cabana, J.; Monconduit, L.; Larcher, D. ; Palacin, M. R. Adv. Mater. 2010, 22, E170.

[3] Zhang W.M. ; Wu X.L. ; Hu J.S. ; Guo Y.G : Wan L.J. Adv. Funct. Mater. 2008, 18, 3941.

[4] Dambournet, D. ; Chapman, K. W. ; Chupas P.J. ; Gerald, R.E.; Penin, N.; Labrugere, C.; Demourgues, A.; Tressaud, A.; Amine, K. J. Am. Chem. Soc. 2011, 133, 13240.
Materials Exploration in Na-Fe-S-O System: Synthesis and Electrochemistry
Authors: Oyama Gosuke , Barpanda Prabeer , Nishimura Shinichi , Yamada Atsuo
Published: February 2020

The current Li ion batteries which employ layered oxides such as LiCoO2, spinel LiMn2O4, and olivine LiFePO4as cathode materials have dominated global markets of secondary batteries. However, rapid expansion of their application has triggered the growing concerns on scarcity and rising costs of Li resources. As one of the most realistic alternatives, Na ion batteries re-attract massive attention owing to its abundance, lower cost, and sustainable production. In this pursuit, Na-Fe-S-O systems are one of the most desirable systems, which are consisted only by earth-abundant and geographically distributed elements. Especially, sulfate compounds are very cheap, being a byproduct of coal power plant, or petrochemical industries.

During the exploration of in the Na2O-FeO-SO3 ternary phase diagrams, we identified some materials with a totally new composition and crystal structure [1]. The target cathode material was obtained via classical solid-state synthesis by ball-milling Na2SO4 and anhydrous FeSO4 followed by annealing the mixed precursors at elevated temperature under an Ar gas flow. The electrode property of as-synthesized cathode material was examined with no special effort for decreasing particle size or carbon coating. The working electrode was formulated by mixing 85 wt% active material, 10 wt% carbon black (Ketjen Black, ECP), and 5 wt% polytetrafluoro- ethylene (PTFE) binder. Figure 1 shows an example of galvanostatic charging and discharging curves measured at a rate of C/10. The initial charging capacity of 98 mAhg-
1 was retained over 10 cycles with small polarization. An average potential of 3.6 V (vs. Na/Na+) is the highest-ever Fe3+/Fe2+redox potential among all known Na-ion cathode materials. The smooth sloppy charging and discharging curves suggests a single-phase reaction mechanism, which is generally favorable from the perspective of homogeneity and kinetics of the reaction.

Details on the compositions and their synthetic conditions will be disclosed in the poster.

References

[1] A. Yamada, P. Barpanda, S. Nishimura, G. Oyama, Patent JP-2013-187914 (2013).

Acknowledgments

This work was supported by the ‘Element Strategy Initiative for Catalysts & Batteries’ (ESICB) project.
New Insight in Sodium Intercalation in MoS2 at Different Stages and the Optimized Cycle Performance for Sodium Ion Batteries
Authors: Wang Xuefeng , Wang Zhaoxiang , Chen Liquan
Published: February 2020

Due to the high abundance and low cost of the sodium (Na), Na-ion batteries are an alternative to lithium-ion (Li-ion) batteries for large-scale energy storage, such as electric vehicles and stationary storage for renewable energies. Similar to the successful lithium intercalation chemistry, Na-ion batteries have recalled much attention recently and a significant achievement have been made. However, the large size of the ionic diameter and ionization potential of the Na ions make it difficult in structural stability and ion diffusion, usually resulting in different reaction mechanisms1.

Transition metal dichalcogenides MS2 (M=Mo, W) and their intercalated compounds belong to a large class of the so-called 2D layered solids. The layers of these materials consist of three interconnected, hexagonally coordinated atomic sheets (S-Mo-S)2. The weak interlayer van der Waals force permits the possible intercalation of some foreign atoms between the layers, such as alkali metal. Li-ion intercalated MoS2 (LixMoS2) has been widely explored and known as intercalation (x<0.5), 2H-1T phase transition (0.5<x<1) and conversion (x>1)3. However, few studies have been focused on the structural change of the host when Na ions are inserted into the MoS2 lattice. Moreover, the electrochemical performance of MoS2for Na-ion insertion needs to be improved.

In this work, in situ and ex situ techniques were combined to monitor the structural changes of MoS2 at atomic levels at various intercalation stages and recognize the reaction products. By optimizing the binder and the cut-off potential, we improve the cycling performance of MoS2 for Na-ion battery by a large margin. When discharged to 0.2 V, the cell shows an initial discharge capacity of 241 mAh g-1 and maintains at 165 mAh g-1 after 70 cycles. However, intercalation of too many Na ions in the host leads to the decomposition of MoS2 into metallic Mo and NaxS2 (x£2). The performance of the cell becomes deteriorated in the subsequent cycles due to large volume expansion and the electrolyte reduction at low potentials (0.01 V) though a reversible capacity up to 440 mAh g-1 can be obtained.

(1) Palomares, V.; Serras, P.; Villaluenga, I.; Hueso, K. B.; Carretero-Gonzalez, J.; Rojo, T. Energy Environ. Sci.
2012, 5, 5884-5901.

(2) Zak, A.; Feldman, Y.; Lyakhovitskaya, V.; Leitus, G.; Popovitz-Biro, R.; Wachtel, E.; Cohen, H.; Reich, S.; Tenne, R. J. Am. Chem. Soc.
2002, 124, 4747-4758.

(3) Fang, X. P.; Hua, C. X.; Guo, X. W.; Hu, Y. S.; Wang, Z. X.; Gao, X. P.; Wu, F.; Wang, J. Z.; Chen, L. Q. Electrochim. Acta
2012, 81, 155-160.
Exfoliated MoS2/C Composite As a High-Performance Anode for Sodium Ion Batteries
Authors: Wang Yunxiao , Seng Kuok Hau , Chou Shulei , Guo Zaiping , Wexler David , Liu Hua Kun , Dou Shi Xue
Published: February 2020

Molybdenum disulphide (MoS2) has a graphite-like structure, where Mo and S atoms are covalently bonded to form two-dimensional S-Mo-S trilayers. It could be a desirable intercalation host material for sodium ions. We report on an exfoliated MoS2/C composite (E-MoS2/C) for SIBs with outstanding electrochemical properties, which possesses a unique grapheme-like structure (Figure 1a). Our strategy to achieve high performances is to use a unique E-MoS2/C composite as an anode material that possesses expanded d-spacing to accommodate large sodium ions. In addition, the exfoliated structure could shorten the Na-ion diffusion pathway and also withstand large volume change due to the buffering space created by the crumpled nanolayers. Simultaneously, the carbon component can effectively increase electrode conductivity. As shown in Figure 1b, various electrolytes were utilized to optimize the cycling performance of E-MoS2/C. The E-MoS2/C is presented as an excellent anode material in 1.0 M NaClO4 with propylene carbonate / ethylene carbonate and 5 wt % fluoroethylene carbonate additive (PC/EC + 5 wt % FEC), with an average working voltage of 1.0 V. Coupled with the average capacity of ~ 400 mAh g-1 for 100 cycles at applied current of 100 mA g-1 (0.25 C) and excellent rate capability (467.7 mAh g-1 at 0.125 C and 290.1 mAh g-1 at 5 C ), as well as high energy density of 400 Wh Kg-1, this material could be a promising anode candidate for SIBs at room temperature.

Figure 1 SEM image (a) and cycling performances (b) of E-MoS2/C at various electrolytes.
Significant Effect of Graphene Coating on Cathode Performence for Lithium-ion Batteries
Authors: Zeng Jiesheng , Li Xifei , Chen Chen , Li Dejun
Published: February 2020

Benefits by high electrical conductive and surface area, graphene has been received great attention in lithium-ion batteries field. In this study, graphene was successfully coated on the LiMn2O4 cathode through a low-temperature treatment. With SEM and TEM techniques the resultant samples were founded that graphene coating layer was uniform and compact, moreover, the spinel structure of LiMn2O4 could not be changed during this process. It was confirmed that this novel coating could offer impressive conductive channels, also decrease Mn dissolution from the reaction between cathode and electrolyte, as demonstrated by the results of EIS and ICP. As a result, in comparison to pristine cathode, graphene coated LiMn2O4 showed higher cyclic performance, better rate capability , and high temperature performance for lithium ion batteries.
Approaching the Theoretical Capacities of LiMnBO3
Authors: Kim Ji Ung , Kim Ji-Young , Cho Hae In , Chang Wonyoung , Cho Byung-Won , Cho Yongsoo , Chung Kyung Yoon
Published: February 2020

In the last decades, there have been a lot of studies on the LiFePO4 as a cathode material for lithium ion batteries. Its major target application was hybrid electric vehicles ( HEV ) and plug-in hybrid electric vehicle ( PHEV ). However, several hurdles remain before LiFePO4 can be deployed on a commercial scale because the material is still not capable enough to the energy density demand required for the electrical vehicles. The polyanion materials based on metal borate can be one of the solutions to replace ( PO4
3- ) anions due to high theoretical capacity, however, it has been reported that metal borate cathode materials could not make full use of its high theoretical capacities. We have successfully developed solid state synthesis method to produce lithium manganese borate ( LiMnBO3 ). Our experiments have shown that well synthesized LiMnBO3 delivers 190 mAh g-1 in the voltage range between 1.5 ~ 4.5 V using constant current-constant voltage ( CC-CV )mode at 1/20 C, which means that the theoretical capacity of LiMnBO3 can nearly be achieved under reasonable current density at room temperature by the simple synthesize method. This synthesis method allows the electrode of LiMnBO3 to deliver high capacity, even when charge/discharge experiments at the high C rate. More details will be discussed at the meeting.
Electrochemical Performance of Polyoxometalates for Cathode Materials of Lithium Battery
Authors: Sonoyama Noriyuki , Uematsu Shinichi , Ni Erfu
Published: February 2020

Polyoxometalates (POM) are very famous cluster ions that can be synthesized self-assembly formation in the solution. These cluster ions behave as independent molecules and show reversible redox activity in the solution. These molecular cluster ions are expected to show different property from the usual cathode materials for lithium ion battery those are the bulk continuum ionic crystals.[1-3] In this paper, we have synthesized Anderson-type POM Na3[AlMo6O24H6] (Fig.1 ) and examined its electrochemical property as cathode materials for lithium battery. In Anderson-type POM, all [MoO6] share the edge with hetero ion [AlO6]. This covalent bond of [MoO6] with unreactive hetero ion would stabilize the structure of the reduced POM.

Anderson-type POMs were synthesized according to the reported method. [4] Obtained samples were mixed with acetylene black with the weight ratio of 1:2 using ball mill. The charge-discharge test and AC-impedance spectra measurements are performed using the coin cells at 25ºC. Lithium metal was used as anode and 1M solution of LiPF6in EC:DEC (3:7 v/v%) was used as the electrolyte. After the charge-discharge measurements, ex-situ XRD and Raman measurements were carried out under Ar atmosphere again.

NMR, FT-IR and Raman spectra of obtained samples agreed with those for reported Anderson-type POM. In Fig. 1, the discharge-charge curves for Na3AlMo6O24H6 were shown. Na3AlMo6O24H6 mixed by ball mill show large capacity over 420 mAh/g. In Fig.2, cycle stability of Na3AlMo6O24H6 was shown. The cycle stability of Na3AlMo6O24H6 was higher than the most representative POM K3PMo12O40 with Keggin type structure. 90% of the initial discharge capacity for Anderson-type POM was retained after 50 cycles, whereas that for KPM decreased steeply in the first 10 cycles. This result suggests Anderson type POM has higher stability than Keggin type POM.

[1] N. Sonoyama et al, J. Power Sources, 196 (2011) 6822.

[2] S. Uematsu et al, , J. Power Sources, J. Power Sources, 217, (2012)13.

[3] E. Ni et al. J Nanopart Res, 15(2013) 1732.

[4] Kenji Nomiya et al. Polyhedron, (1987) 213.
Particle Shapes and Surface Structures of Olivine NaFePO4 for Sodium-Ion Batteries
Authors: Whiteside Alexander , Fisher Craig Andrew James , Parker Stephen C. , Islam M. Saiful
Published: February 2020

The expansion of batteries into electric vehicle and grid storage applications has spurred the development of alternative cathode materials such as olivine phosphates. Building on previous studies of the lithium-ion cathode material LiFePO4, we present atomistic simulations of olivine-structured NaFePO4. We discuss differences in its morphology compared to its Li analogue, in the context of new simulations on the bulk properties.[1] The calculated equilibrium morphology is mostly isometric in appearance, with (010), (201) and (011) faces dominant. Exposure of a significant fraction of (010) surface is significant because it is normal to the most facile pathway for ion conduction. The equilibrium morphology of an NaFePO4 nanoparticle is proportionally thinner along the [010] axis than that of an LiFePO4 nanoparticle, which should also be beneficial for high ion intercalation-deintercalation rates because of the 1D nature of the conduction pathway.[2] We also simulated the effect of stabilising the (010) surface upon the particle morphology (shown below), concluding that a significant reduction in the surface energy is required to obtain the experimental “platelet” structure.

Figure: Variation in the equilibrium morphology of NaFePO4 with the (010) surface energy, all other surface energies being held constant.

[1] R. Tripathi, S. M. Wood, M. S. Islam and L. F. Nazar, Energ. Environ. Sci., 6, 2257-2264 (2013).

[2] A. Whiteside, C. A. J. Fisher, S. C. Parker and M. S. Islam, Phys. Chem. Chem. Phys. (2014) (submitted).
Hollow Carbon Nanosphere/Germanium Metal Composite Li-Ion Anode
Authors: Banek Nathan A , Hays Kevin Alan , Wagner Michael J
Published: February 2020

Since their introduction, lithium ion batteries have become ubiquitous for powering portable electronic devices. However, the charging rate of graphite (by far the most common anode material) is dependent on lithium diffusion into the material. Highly graphitic hollow carbon nanospheres (HCNS) have a tremendous advantage over micron-sized graphite particles as the diffusion path length is on the nanoscale, 3 orders of magnitude shorter than graphite’s, facilitating rapid charging within a few minutes, rather than many hours. In addition, HCNS anodes cycle stably in inexpensive low melting electrolytes, cycling with excellent capacity retention and high rate at temperatures as low as -50 ˚C. Unfortunately, HCNS anodes have lower specific capacity compared to those made with graphite (~220 mAh/g vs. ~330 mAh/g).(1) However, the high surface area, good electrical conductivity and excellent electrochemical stability of HCNS make it a promising support material for other high capacity lithium alloying metals, suggesting the possibility of significantly higher specific capacities, much better low temperature performance and charging rates than graphite-based anodes. Here we present our studies to date on the incorporation of germanium metal which is second only to Si in gravimetric capacity as a Li alloying material (1385 mAh/g) and nearly equal to it in volumetric capacity (7372 mAh/mL), into HCNS anodes.

Syntheses were performed by multiple reduction methods of germanium precursors in the presence of HCNS to produce conductive composites of HCNS. Various Ge morphologies were observed from each synthesis method. Using these composites, electrodes were prepared with different binder materials and tested in different electrolytes at various potentials in attempt to obtain a high capacity, long cycle-life anode while maintaining nearly 100 % coulombic efficiency. A stable capacity of 950 mAh/g of Ge was obtained when cycling from 1.0 to 0.055 V and long-term coulombic efficiency values were greater than 99.7 %. TEM analysis revealed the HCNS particles to be coated with Ge. Performance comparisons of multiple Ge/HCNS composites with differing cycling environments will be presented.

(1) Michael J. Wagner, J. Thomas McKinnon, J. Cox and K. Gneshin, “Hollow Carbon Naonsphere Based Secondary Cell Electrodes”, United States Patent 8,262,942, September 11, 2012.
Sns 2D Nanosheets with High Energy Density for Next-Generation Rechargeable Battery Applications
Authors: Song Kyeongse , Cho Eunbi , Jung Jaepyeong , Kang Yong-Mook
Published: February 2020

Beyond the human being, economical energy providing/consumption, development of advanced energy conversion system and finding effective way for energy transport are considered as global urgent task which must be accomplished as soon as possible in modern society based on the environmental concerns and climate changes. In this regard, with the purpose of reducing consumption of natural resources as well as decrease of environmental pollution from internal combustion-engine, much effort has been spent on developing new energy storage system (ESS) and electric vehicles (EVs) powered by various batteries, fuel cell and hybrid system. However there are several quite requirements such as high power/energy density of battery, improved safety, and high reliability against with external environmental condition. Even if only considered in power/energy density of battery, state-of-the-art of rechargeable battery system have obvious limit although wide research and development has been conducted to meet requirements for next-generation battery. Therefore, lithium-oxygen batteries and Na ion batteries have engaged intensive attention owing to their high theoretical energy density. Yet, present lithium-oxygen battery and Na ion battery exhibit low efficiency and cyclic degradation, thus limiting their commercialization as next-generation power sources. Therefore, there are many attempts to design tailored materials for as an active material of Na ion battery or catalyst of lithium-oxygen batteries. Among them, metal sulﬁdes have been extensively studied due to their fundamental properties for important technological applications.

Here, we suggest SnS 2D nanomaterials with an unique layered CdI2-type structure with tin atoms sandwiched between two layers of hexagonal close-packed sulphur atoms. Thus, we found that such unique structure is facilitating not only intercalation of Na ions but also have catalytic activity for ORR/OER in lithium-oxygen batteries.
Simple and Large Scale Synthesis of SnSX Nano-Belts, Flowers and Sheets for Li-Ion Battery Anode Applications
Authors: Bhaskar Akkisetty , Deepa Melepurath , Narasinga Rao Tata
Published: February 2020

In this report, a variety of nanostructured materials of SnSx (such as nanobelts, nanoflowers and interconnected nanosheets) were prepared by hydrothermal synthesis method using mercaptopropionic acid (MPA) as the structure directing agent. By simply adjusting the amount of MPA in the precursor formulations and heating period, nanobelts, nanoflowers and interconnected nanosheets of SnSx were obtained. The detailed growth processes of SnS2/SnS nanoflowers from nanobelts are elucidated. Morphological evolution of the definitively shaped SnSx nanostructures was followed by scanning electron microscopy. X-ray diffraction (XRD) analyses confirmed an orthorhombic crystal structure for SnS nanobelts. The XRD patterns of SnSx nanoflowers and interconnected nanosheets show a mixed phase comprising an orthorhombic crystal structure of SnS coupled with a hexagonal crystal structure of SnS2. The SnSx nanostructured materials demonstrated extremely large capacities when used as Li-ion battery anodes. Among the various anode nanostructures that we studied, the anode based on SnS2/SnS interconnected nanosheets showed an exceptionally high capacity. Initially it showed a reversible capacity of 800 mAh g-1 at a current density of 100 mA g-1 and even after 50 cycles it retained a capacity of 470 mAh g-1 with almost 97% Coulombic efficiency. The SnS2/SnS interconnected nanosheets also exhibited an excellent rate capability even at a very high current density (1160 mA g-1) a charge capacity of 360 mAh g-1 was obtained. We demonstrate that this facile hydrothermal route assisted by MPA adopted herein for the development of SnSx based high performance anodes is also extendable to other potential inorganic anode materials.
Porous FeF3 Microspheres/Reduced Graphene Oxide Composites as a High Performance Cathode Material for Lithium-Ion Batteries
Authors: Jung Hyeyun , Shin Jihyun , Kim Yonggyeong , Lee Jung Kyoo , Kim Jongsik
Published: February 2020

Lithium-ion batteries (LIBs) have high energy density, high operating voltage, environmental friendliness and long cycle lifetime. They are applied to the energy storage system such as the mobile phones, laptop computers, and electric-vehicles (EVs). However, modern energy storage device requires the development of LIBs with enhanced reversible specific capacities, which are mainly limited by electrode materials, especially cathode materials. Therefore, it is needed to develop the cathode materials with higher theoretical capacity. FeF3 is of great interest as a potential alternative cathode material for LIBs because of its low cost, abundance, environmental friendliness, and high theoretical capacity of about 237 mAhg−
1 in the voltage range of 2.0−4.5 V and 712 mAhg−
1 in the 1.5−4.5 V, respectively.[1, 2] However, FeF3 has drawbacks of poor capacity retention and rate performance because of its low intrinsic electrical conductivity and slow diffusion of lithium ions.

In this study, porous FeF3 microspheres/reduced graphene oxide (r-GO) composites were synthesized by a simple hydrothermal route with aqueous HF solution. The size of the microspheres was controllable simply by adjusting the amount of the graphene oxide from about 1 to 10 wt% in the precursor solution. The oxygen functional groups of the graphene oxide played a role as an anchoring site for the FeF3 precursor and its crystallization to primary FeF3 nanoparticles, which were structured as a building block to porous FeF3 microspheres. The FeF3 microspheres/r-GO composites showed the improved discharge capacity and cycling stability in the voltage ranges of 1.5-4.5 V and 2.0-4.5 V at room temperature compared to those of bulk FeF3. For example, they delivered an initial discharge capacity of about 195 mAhg-1 at 0.1 C rate with 0.27% fading per cycle during 50 cycles in the 2.0-4.5 V. The composites also showed the significantly enhanced rate capabilities in the range of 0.1-20 C (e.g., about 170 mAhg-1 at 1 C rate). The detailed electrochemical data in the range of 1.5-4.5 V will be presented as well.

References

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[2] F. Badway, F. Cosandey, N. Pereira, G. G. Amatucci, J. Electrochem. Soc.
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