bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low Cost Membrane-Free Single Chamber Zinc Bromine Battery for Grid-Scale Electrochemical Energy Storage Applications
Authors: Biswas Shaurjo , Senju Aoi , Hodson Thomas , Steingart Daniel A 
Published: February 2020

Climate change is a major global concern which can potentially be addressed by integrating renewable energy sources and low cost grid scale electrochemical energy storage (EES) systems. Most research efforts to improve energy storage have been directed to redox flow, lithium-ion and next generation sodium and multivalent batteries. The focus has been on incremental improvements in cost, and efficiency of electrode active materials and electrolytes. Most of these batteries still employ traditional cell designs with expensive passive components. Unfortunately, this approach results in the balance-of-plant costs far outweighing the cost of electrochemically active materials. Techno-economic analyses indicate that the cost of energy storage must be <$100/kWh and power cost <$600/kW. Commercially available EES systems today do not meet these targets. In addition, battery life and energy efficiencies must be over 10,000 cycles and 70%, respectively, to be a sustainable option. Based on these targets, a more holistic approach is needed when considering new energy storage system materials and designs.

Here, we discuss the design and working principle of a membrane free, non-flowing single-chamber zinc-bromine (SC-Zn-Br2) battery that utilizes the physical properties of liquid bromine, a porous carbon foam electrode, and also allows zinc dendrites to form freely. With this design, we eliminate the need to use failure prone and expensive passive components such as membrane separators, bromine complexing agents, flow-rated hardware, and control software as employed in traditional Zn-Br2 redox flow batteries (RFB). The ultimate figure of merit for feasibility in grid-scale EES system is $/kWh over its lifetime (cycles) at a given energy efficiency, or levelized cost of energy stored (LCOES). We demonstrate an SC-Zn-Br2 system with a maximum specific capacity of 89 mAh/g and energy density >150 Wh/kg (normalized to the mass of ZnBr2 salt in the electrolyte) and cell cost of $94/kWh including passive components. We achieve coulombic and energy efficiencies of up to 95% and 75%, respectively, for over 1000 cycles. The LCOES of SC-Zn-Br2 is shown to be an order of magnitude better than Zn-Br2 and vanadium RFB, as well as grid-scale lead-acid batteries and Li-ion batteries.
Crystal Structure of Na2Fe2(MoO4)3 As a Positive Material for Sodium-Ion Batteries: Determination of the Inserted Sodium-Ion Positions from Powder X-Ray Diffraction Data
Authors: Heo Jongwook W , Hong Seung-Tae 
Published: February 2020

Rechargeable sodium-ion batteries (NIBs) have been considered as promising candidates for alternatives to lithium-ion batteries due to the low cost and abundance of sodium. Recently, Fe2(MoO4)3 has received an attention as a positive electrode material for NIBs.1-4 There are two polymorphic phases for Fe2(MoO4)3: the low-temperature monoclinic phase and the high-temperature orthorhombic one,1 where the monoclinic one was recently reported as the positive material for NIBs. The previous reports mainly focused on synthesis and methods to improve the cycle and rate performances.2-4 Regarding the structure of electrochemically sodium-intercalated phase Na2Fe2(MoO4)3, only the cell parameters and space group were reported:1,5 the positions of the inserted sodium ions have never been determined at the best of our knowledge.
In this work, the monoclinic Fe2(MoO4)3 has been synthesized by sol-gel method at 600°C from Fe(NO3)3.9H2O, (NH4)6Mo7O24.4H2O and citric acid. The electrodes consisted of Fe2(MoO4)3 (80 wt %), Super-P carbon (10 wt %), and polyvinylidene fluoride binder (10 wt %). The sodium-intercalated phases NaxFe2(MoO4)3 were obtained by the galvanostatic discharge in the electrolyte of 1M NaClO4 in acetonitrile with the activated carbon as the counter electrode. Reversible structural changes of NaxFe2(MoO4)3 (0 ≤ x ≤ 2) were observed in ex-situ powder X-ray diffraction patterns during the discharge and charge cycle. The crystal structure of the fully sodiated phase of the monoclinic Na2Fe2(MoO4)3 has been determined for the first time using the techniques of structure determination from powder X-ray diffraction data, locating the inserted sodium-ion positions in the unit cell. The results presented here would provide an important basis for understanding the mechanism of sodium intercalation into Fe2(MoO4)3.

References

1. J.L. Yue, Y.N. Zhou, S.Q. Shi, Z. Shadike, X.Q. Huang, J. Luo, Z.Z. Yang, H. Li, L. Gu, X.Q. Yang and Z.W. Fu, Scientific Reports 5, 8810 (2015).
2. Q. Sun, Q.Q. Ren and Z.W. Fu, Electrochem. Commun. 23, 145 (2012).
3. V. Nguyen, Y. Liu, Y. Li, S.A. Hakim, X. Yang and W. Chen, ECS J. Solid State Sci. Technol. 4, M25-M29 (2015).
4. V. Nguyen, Y. Liu, X. Yang and W. Chen, ECS Electrochem. Lett. 4, A29-A32 (2015).
5. P.G. Bruce and G. Miln, J. Solid State Chem. 89,162 (1990).

Figure 1
Electrospun Hollow Carbon/Sulfur Nanofiber for Lithium-Sulfur Battery
Authors: Yun Jong Hyuk , Kim Joo-Hyung , Kim Do Kyung 
Published: February 2020

Lithium ion battery (LIB) is the most widely used rechargeable battery for portable devices because of their high energy density (387 Wh kg-1) and long cycle life. Nevertheless, the energy density of LIBs is insufficient to meet the demands for grid energy storage system or electrical vehicles. Lithium sulfur battery (LSB) is one of the most promising systems for alternative rechargeable battery. Elemental sulfur has a high theoretical specific capacity of 1675 mAh g-1 and lithium-sulfur battery has a theoretical energy density of 2500 Wh kg-1. Moreover, LSB has many advantages such as low cost, non-toxicity and abundance. In spite of the considerable promises, there are multiple challenges must be solved; intrinsic poor electrical conductivity of sulfur (5 × 10-30 S cm-1 at 25 oC), dissolution of polysulfides (Li2Sx, 4≤x≤8) in electrolyte and large volumetric expansion (~80%) of sulfur during cycles. To overcome the problems, carbon based materials such as porous carbons, hollow carbon spheres, CNTs, graphene have been investigated as a conductive and structural matrix for carbon/sulfur composites. Although the above-mentioned composites showed outstanding improvement of capacity and cyclability, the specific capacity could not reached near the theoretical value yet. Additionally, finding a suitable structures for high areal capacity which is able to accommodate a high sulfur content is the issue for commercialization of LSBs. In this study, we developed a carbon/sulfur electrode which is focused on electrode design. Electrospun hollow carbon/sulfur nanofiber was designed for cathode material and carbon matrix could be a current collector itself. Because of the thin nanosized structure, electrons could reach the inner part of sulfur so that the sulfur was easily utilized for electrochemical reaction and showed high specific capacity due to high utilization of sulfur. Also, the resulting intertwined nanofibers showed porous structure. Highly porous structure accommodated electrolyte effectively and offered abundant electrochemical reaction sites with a large surface area. Moreover, this electrode was produced easily with simple electrospinning method and showed high areal capacity. We investigated the performance of the carbon/sulfur nanofiber cathode by electrochemical test. The morphology was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
Sulfur-Embedded Polymers for High Performance Li-S Batteries
Authors: Choi Jang Wook 
Published: February 2020

Lithium–sulfur (Li–S) batteries have received considerable attention because high gravimetric capacity of sulfur can enhance the energy density of the cell far beyond those of current lithium-ion batteries (LIBs). However, the shuttling process originating from polysulfides dissolution and the low electronic conductivity of sulfur impose a significant technological bottleneck for practical application of Li-S cells. As attempts to overcome these intrinsic drawbacks of sulfur cathodes, in this presentation, I will introduce sulfur-embedded polymer designs, such as sulfur-containing covalent triazine frameworks1 and sulfur-embedded benzoxazine polymers2. Both polymers exhibit extraordinary cyclability utilizing well-dispersed sulfur domains designed from the monomer-level molecular structures. Especially, both polymer classes showed superior initial Coulombic efficiencies and volumetric capacities, both of which have been difficult to achieve with conventional sulfur cathodes.

1Elemental Sulfur Mediated Facile Synthesis of a Covalent Triazine Framework for High Performance Lithium-Sulfur Batteries,
Angew. Chem. Int. Ed.
, 2016, 55, 3106-3111

2Under review
Voltage Delay Action of Na Metal in Na/MnO2 Non-Aqueous Cells
Authors: Kishore Brij , Munichandraiah N 
Published: February 2020

The Li based battery systems, namely Li-ion, Li-O2 and Li-S batteries have occupied top importance in research and development activities at present. However, Na based battery systems are gaining interest for the next generation non-aqueous batteries. This is primarily because of limited and uneven global resources of Li for large scale production of Li-ion batteries for future applications such as electric vehicles. Plentiful resources of Na and its electrochemical properties close to those of Li have instigated research activities on Na-ion batteries similar to Li-ion batteries. Electrode materials suitable for Na-ion batteries are under investigations and they are characterized for their electrochemical properties by assembling experimental cells in combination with Na metal as the counter electrode as well as reference electrode [1]. Primary batteries employing Na metal as the anode similar to Li based primary batteries are also expected to gain momentum [2]. The cells employing Na metal in non-aqueous electrolytes experience voltage delay on initiation of cell discharge. The voltage delay action arises due to the presence of surface film on Na.
In the present studies, Na/MnO2 cells are assembled in a non-aqueous electrolyte and the voltage delay properties are investigated. Coin cells of type CR2032 with Na foil and MnO2 coated stainless steel mesh as the negative and positive electrodes, respectively, are assembled. The electrolyte was 1 M NaPF6 in a mixture of ethylene carbonate and propylene carbonate (1:1 by volume). Na foil was sliced from a lump of Na in Ar atmosphere glove box before the cell assembly. Amorphous MnO2 was used as the positive electrode material. As shown in Fig. 1 typically, there is a large voltage drop on commencing the cell discharge by passing current in galvanostatic mode. Following the instantaneous voltage fall from open circuit voltage (V1) to dip voltage (V2), then, cell voltage rises gradually and reaches the operating plateau voltage (V3) of the cell. The surface film on Na exhibits its first appearance and it undergoes dielectric breakdown in the high field, which are reflected in the initial voltage fall. Subsequent to the breakdown of surface film, bare Na surface contacts the non-aqueous electrolyte and undergoes oxidation to Na+ ions under the galvanostatic conditions with a simultaneous building of electric double layer. From the data obtained under several experimental conditions such as current density and cell ageing, the properties of surface film on Na metal are evaluated. Results of these studies will be discussed.

References:

1. L. P. Wang, L. Yu, X. Wang, M. Srinivasan and Z. J. Xu, J. Mater. Chem. A,
3, 9353 (2015).
2. Brij Kishore, G. Venkatesh, and N. Munichandraiah, J. Electrochem. Soc.,
162, A839 (2015).

Figure 1
Surface Modifications of LiMn2O4 electrode for Aqueous Lithium Ion Batteries
Authors: Mun Junyoung , Tron Artur V. , Kim Jaemin , Go Nakgyu , Jo Yong Nam , Choi Wonchang 
Published: February 2020

1. Introduction

The rechargeable lithium-ion batteries (LIBs) have been considered as the power sources for the various applications from portable devices to high power applications such as electric vehicles and power storage for renewable energy [1]. However, their safety concerns and high cost are issues restricting their field for large scale energy storage system because the conventional LIBs contain the large energy and dangerous carbonate electrolyte. In this regards of safety and cost, the aqueous electrolyte can be the best candidate [2]. However, its practical application was limited due to its decreasing cycle life from poor electrochemical stability window. Here, we have shown that surface modifications of LiMn2O4 showed highly improved rate and cycle life in aqueous electrolyte.

2. Results and discussion

The effect of the surface coating on the electrochemical properties of LiMn2O4 cathode in aqueous electrolyte solution was investigated by systematic electrochemical and instrumental analyses. The electrochemical performance of pristine LiMn2O4 and coated LiMn2O4 is presented. Despite the high ionic conductivity of the aqueous electrolyte (1 M Li2SO4 in water), the pristine LiMn2O4 did not show the high rate capabilities. In detail, the pristine and coated LiMn2O4 by 1,2, and 3wt.% AlF3 in aqueous electrolyte deliver the initial discharge capacity of 109.7, 106.6, 103.4 and 99.0 mAh g−1 at 1 C, respectively. The AlF3 coating has a dual role of surface stabilizer and resistance for lithium transportation. Based on these results, it is confirmed that the resistance from the surface failure mode of LiMn2O4 could be a main hurdle for cycle decaying especially in the aqueous electrolyte. After the surface modification of the electrochemically stable inorganic species, the rate capability and the cycle life are further improved. This coating enhance the surface stability to the aqueous solution and presents very promising cycle and rate capabilities for the development of ARLBs. Furthermore, they are investigated in detail by using XPS, SEM and TEM analyses.

Acknowledgments

This research was supported by the Post-Doctor Research Program (2014-2015) through the Incheon National University (INU) and the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Science, ICT & Future Planning (NRF-2014R1A1A1038248).

Reference

[1] M.R. Palacin, Recent advances in rechargeable battery materials: a chemist’s perspective, Chem. Soc. Rev. 38 (2009) 2565-2575.
[2] W. Li, J.R. Dahn, D.S. Wainwright, Rechargeable Lithium Batteries with Aqueous Electrolytes, Science 264 (1994) 1115-1118.
Honeycomb-Layer Structured Na3M(II)2M(V)O6 Cathode for Sodium-Ion Batteries
Authors: Nam Kyung-Wan 
Published: February 2020

The necessity to find sodium ion battery cathodes with high capacity and improved cycle life has stimulated the research on sodium containing layered transition metal oxides. With this perspective, we have examined the electrochemical properties of highly ordered, honeycomb layered oxide Na3M(II)2M(V)O6, with monoclinic super structure as a cathode in sodium ion battery. One of this class materials, Na3Ni2BiO6, is able to reversibly deliver specific discharge capacities of up to 109 mAh/g with very flat voltage plateaus ~3.5V vs. Na/Na+. Complex structural changes occuring during charging/discharging is investigated by using in situ X-ray diffraction (XRD). Long range- as well as local- structures at different charged/discharged states have been also probed ex situ using combined synchrotron based x-ray techniques such as high resolution XRD (HRPD) and extended X-ray absorption fine structure (EXAFS). The Ni3+/Ni2+ active redox couple during charge/discharge is also confirmed by X-ray absorption near edge structure (XANES) spectroscopy.
Tailored Transition Metal Oxide Spheres Using Versatile Polymer-Template for Sodium-Ion Battery Cathodes
Authors: Song EunHee 
Published: February 2020

Transition metal oxides have been studied as positive- and negative-electrode materials for sodium-ion batteries (SIBs). In this study, we report the strategic synthesis methods of tailored cathode materials for high performance SIBs using external-stimuli responsive polymer particles and water-in-oil system. The primary particles consisting of the polymer and metal precursors are fabricated by introduction of various metal ions and polar molecules into the three-dimensional cross-linked polymer spheres in aqueous solution. The assembled secondary metal oxide spheres with tailored structures were prepared by water-in-oil system and heat treatment in high purity oxygen. When tested in an electrochemical Na-half cell, the tailored transition metal oxide spheres exhibit good Na storage capabilities.
Nanorod Assembly in a Spherical Secondary Particle for High-Energy Sodium Ion Batteries
Authors: Hwang Jang-Yeon , Sun Y.-K. 
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. 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 and full concentration gradient 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 various analysis technique. Micro-compression testing and single particle electrochemical measurement results demonstrate the robustness of the spherical particles and the associated Na+ ion mobility in the particles. These significant improvements provided by the tailored structure are appealing for utilizing sodium ion. 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.
Study on Lithium-Sulfur Batteries
Authors: Wang Yong-Gang , Wang Lina , Yuan Shouyi , Xia Yong-Yao 
Published: February 2020

Lithium-Sulfur (Li-S) batteries have recently raised worldwide attention owning to the high specific theoretical energy density of sulfur (2600Wh kg-1), the low cost and the wide availability of sulfur. However, the practical application of lithium-sulfur batteries has been hindered by several challenges, such as the shuttling of polysulfide intermediates, the large volume expansion of sulfur during charge/discharge and the dendrites formation on Li-anode. In this talk, we will introduce our recent investigation about Li-S batteries, including physical and chemical immobilization of sulfur to improve cycling stability, segregator optimization to minimize the shuttling effect and design of ionic liquids based electrolyte system to reduce the self-discharge. Finally, we introduce a lithium-ion sulfur battery based on a Li2S cathode using a dual-phase electrolyte (Li2S/electrolyte-1/LISICON/electrolyte-2/Li) and then replaced the Li anode with Al and graphite, which demonstrates a proof of concept of metal Li free Li-ion Sulfur battery.

Reference

[1] S.Y. Yuan, Z.Y. Guo, L.N. Wang, S. Hu, Y. G. Wang*, Y.Y. Xia*, Adv. Sci.
2015, 2: 1500071.
[2] S.Y. Yuan, J.W. Bao, L.N. Wang, Y.Y. Xia, D.G. Truhlar*, Y.G. Wang*, Adv. Energy Mater., 2015
, 1501733.
[3] L.N. Wang, J.Y. Liu, S. Haller, Y.G. Wang*, Y.Y. Xia*, Chem. Commun.,
2015, 51: 6996.
[4] L.N. Wang, J.Y. Liu, S.Y. Yuan, Y.G. Wang*, Y.Y. Xia*, Energy Environ. Sci.,
2016, 9: 224.
[5] L.N. Wang, Y.G. Wang*, Y.Y. Xia*, Energy Environ. Sci.,
2015, 8: 1551.
First Principles Studies of Fe, Co, Mn, and Ir-Based Hybrid Li-Ion/Li-Oxygen Battery Materials
Authors: Li Liang , Kinaci Alper , Ford Denise , Letchworth-Weaver Kendra , Chan Maria K. Y. 
Published: February 2020

In the Center for Electrochemical Energy Science (CEES) Energy Frontier Research Center, we are investigating a new class of energy storage materials – hybrid Li-ion/Li-oxygen materials – that combine transition metal and oxygen redox chemistries to deliver high energy storage capacity [1, 2, 3]. The electrochemical reactions, structural and electronic structure evolution of these materials are complex, requiring a combination of in-depth characterization and first principles modeling. In this talk, we will report on a comparison study of several examples of hybrid Li-ion/Li-oxygen materials using density functional theory calculations. We will discuss the structural, thermodynamic, and electronic structure reasons for differences in reaction pathways and competition between transition metal vs oxygen redox chemistries. Insight towards selecting and designing promising hybrid battery materials gleaned from the comparison will be discussed.

References

[1] L. Trahey, C. S. Johnson, J. T. Vaughey, S.-H. Kang, L. J. Hardwick, S. A. Freunberger, P. G. Bruce, M. M. Thackeray, “Activated Lithium-Metal-Oxides as Catalytic Electrodes for Li-O2 Cells,” Electrochemical and Solid-State Letters, 2011, 14, A64.
[2] M. M. Thackeray, M. K. Y. Chan, L. Trahey, S. Kirklin, and C. Wolverton, “Vision for Designing High-Energy, Hybrid Li Ion/Li–O2 Cells,” Journal of Physical Chemistry Letters, 2013, 4, 3607.
[3] Z. Yang, L. Trahey, Y. Ren, M. K. Y. Chan, C. Lin, J. Okasinski, and M. M. Thackeray, “In-Situ High-Energy Synchrotron X-ray Diffraction Studies and First Principles Modeling of α-MnO2 Electrodes in Li-O2 and Li-ion Coin Cells,” Journal of Materials Chemistry A, 2015, 3, 7389.

Acknowledgement

This work was supported as a part of the Center for Electrochemical Energy Science, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences under award number DE-AC02–06CH11. Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.