bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Potassium Titanate As Potential Anodes for Sodium Ion Battery
Authors: Zhang Qing , Li Huiqiao 
Published: February 2020

Sodium ion batteries (SIBs) have been intensively investigated as a low cost alternative for lithium ion batteries due to the abundance of sodium ion on the earth and its similar chemical properties to lithium.[1] Taking low cost, wide abundance and high security into consideration, titanium based intercalation materials should be the most promising choice for their low redox potential (Ti3+/Ti4+) relative to the Na+/Na redox potential and abundant reserves among various sodium storage anode materials.[2] In the past few years, researchers have explored many titanium-based materials as potential anode materials for SIBs, such as various TiO2 polymorphs, including anatase, rutile, TiO2-B. Ternary sodium titanates-based materials with related crystal structures also greatly enrich the kinds of anode materials. While, the practical application of Ti-based anodes in SIBs is severely hindered by their inferior rate capabilities and relatively low capacity resulting from both extremely poor electronic conductivity and sluggish sodium ion diffusion.
Here, we proposed K2Ti6O13 with an analogue tunnel structure with Na2Ti6O13 as a new anode for sodium ion batteries.[3] And by a soft chemistry method, we can successfully get ultrafine K2Ti6O13 nanowires with a diameter of only 5-10 nm, which grow perpendicularly to the tunnel direction. The ultrafine nanowires greatly shorten the diffusion path length of Na-ion and endow K2Ti6O13 a remarkably improved reactivity as shown in Fig.1. This new titanium based anode material exhibits a high charge capacity of 186 mAh g-1 at 20 mA g-1 and excellent rate performance of 61 mAh g-1 at 1000 mA g-1. The capacity is nearly 3 times that of the bulk phase. This suggests that shortening the diffusion length especially in the diffusion direction by design nanostructure is very important to promote the reactivity of Ti-based material for sodium storage. Furthermore, we introduce Ti3+ into this Ti-based material to enhance the inherent electronic conductivity. We synthesized the hollandite-type KxTiO2 nanorod by a facile carbothermal reduction method and used it as a new sodium ion anode. The as-prepared hollandite-type KxTiO2 shows uniform nanorod of 50 nm with a carbon coating. The carbon can not only partially reduce the Ti (IV) of the precursor to Ti (III), but also limit the particle-size growth to some extent during the heat treatment process. Morever, the carbon coating could also efficiently improve the conductivity of the active materials. This new material can deliver about 135 mAh g-1 at 20 mA g-1 and exhibit great rate capability with 67 mAh g-1 at 1000 mA g-1. It is obvious that these new potassium titanates with the high capacity and excellent rate performance can serve as potential sodium ion anodes.

References:

[1] N. Yabuuchi, K. Kubota, M. Dahbi and S. Komaba, Chem. Rev., 2014, 114, 11636.
[2] M. Doeff, J. Cabana and M. Shirpour, J. Inorg. Organomet. Polym., 2014, 24, 5.
[3] A. Rudola, K. Saravanan, S. Devaraj, H. Gong and P. Balaya, Chem. Commun., 2013, 49, 7451.

Figure 1
Prussian Blue Analogue Materials for Sodium-Ion Batteries
Authors: Lee Hyun-Wook , Cui Yi 
Published: February 2020

Battery-based electrochemical storage is particularly attractive because of its high energy efficiency and ease of deployment, and lithium-ion batteries (LIBs) are one of the most well developed of these options. Sodium-ion batteries (SIBs), which replace lithium with abundant and inexpensive sodium, have received a great deal of attention recently. Similarities in manufacturing techniques between SIBs and LIBs may significantly accelerate their technological advance. Nevertheless, several scientific challenges still need to be resolved before the performance of SIBs becomes competitive with that of LIBs. In particular, the higher negative redox potential of Na compared to that of Li results in lower cell voltages and consequently lower energy densities. Moreover, the larger size of Na+ relative to Li+ causes slower solid-state diffusion in the active materials and leads to lower energy efficiencies when the batteries are rapidly charged or discharged. High capacity electrode materials with fast solid-state kinetics are therefore required in order to compensate for these intrinsic limitations.
In this presentation, I will introduce low-vacancy, sodium manganese hexacyanomanganate (MnHCMn) as a viable cathode material for SIBs. The as-synthesized MnHCMn shows a monoclinic crystal structure composed of nonlinear Mn–N≡C–Mn bonds and containing eight large interstitial sites occupied by Na+ ions. Our experiments demonstrate a high specific capacity of 210 mAh g-1 and excellent capacity retention at high rates in a propylene carbonate electrolyte. We discovered a novel mechanism wherein small lattice distortions allow for the unprecedented storage of 50% more sodium cations than in the undistorted case. These results represent a step forward in the development of sodium-ion batteries.
In Searching for Electrolyte Compatible with NaMnO2 Cathode Material in Sodium Ion Battery
Authors: Ma Tianyuan , Xu Gui-Liang , Li Yan , Song Boao , Zeng Xiaoqiao , Sun Chengjun , Ren Yang , Heald Steve M. , Jorne Jacob , Shahbazian-Yassar Reza , Amine Khalil , Chen Zonghai 
Published: February 2020

In the past few years, concerns over lithium reservoir depletion have driven researchers to go beyond lithium ion battery[1]. Sodium ion battery (SIB) has been considered as a promising candidate as sodium is highly abundant and widely distributed around the world.
One of the challenges in state of the arts sodium ion battery is searching for cathode materials that can provide electrochemical performance comparable to lithium ion battery and electrolytes compatible with the related cathode materials. Among the reported cathode materials for SIB, O3 or O'3 type layered transition metal oxides are of great interest due to their high specific capacities[2]. In order to get a better understanding on these transition metal oxides, it is important to decouple the mixing transition metals and carry out a thorough investigation on the end member of the series. One of the end members, NaMnO2, has been reported with high specific capacity but shown low coulombic efficiency[3], which may be associated with electrolytes decomposition. Therefore, it is critical to search for a suitable electrolyte as well as additives.
The influence of FEC (Fluoroethylene Carbonate) additive and some commonly used electrolytes in sodium ion battery were examined in NaMnO2/Na coin cells. For the cell using 1M NaClO4/PC as electrolyte, coulombic efficiency is relatively low at first but increases to 94% within ten cycles. While the coulombic efficiency of NaPF6/EC+DMC stays as low as 80% till 40 cycles. Apparently, the coulombic efficiency can be improved by adding FEC as additive in both electrolytes. The study regarding function mechanism for the FEC additive will be comprehensively understood by in-situ high energy X-ray diffraction and high precision electrochemical test, which could serves a good guide for the exploration of suitable electrolytes for high performance cathode materials of SIB.

Figure 1
New Carbon Materials with Large Closed Pore Volume for the Anode of High Energy Na-Ion Batteries
Authors: Kano Akira , Okano Tetsuyuki , Hojo Nobuhiko , Ito Shuji , Fujimoto Masahisa , Nakura Kensuke 
Published: February 2020

Recently the demand for rechargeable batteries with high capacity, high power, long life, high reliability, and low cost has been increasing. While Li-ion batteries offer the highest energy density among present battery technologies, the higher cost and insufficient resources of lithium is a bottleneck to enabling their wider use. Na-ion batteries, where sodium acts as the current carrier, are attractive alternatives to Li-ion batteries because of the lower cost and abundance of sodium. However, the energy density of Na-ion batteries is still lower than that of Li-ion batteries, therefore the development of the active materials achieving a higher energy density is eagerly anticipated.
For anode materials in Na-ion batteries, a non-graphitized carbon, such as hard carbon, is well-studied in contrast to Li-ion batteries, where graphite is usually used as the anode material. The capacity of non-graphitized carbon in Na-ion batteries is reported to be 200 - 300 mAh/g [1,2]. In Na-ion insertion process, it is proposed that Na-ions are inserted between stacked graphenes in the higher potential above ca. 0.2 V vs. Na+/Na, and then nano-pores are filled during electrochemical reaction in the lower potential region [1,2].
In our previous research, we focused on the effect of the pore structure of carbons, and found a linear relationship between the reversible capacity in the range of 0.2 - 0 V vs. Na+/Na and the closed pore volume of non-graphitized carbons. This result suggests that Na-ion could be inserted reversibly into the closed pore of non-graphitized carbons, and thus the non-graphitized carbon with large closed pore volume is a promising anode material for higher capacity Na-ion batteries [3].
In this study, we synthesized a new carbon material with a large closed pore volume using the carbon sources including a pore-forming agent as the starting material. It has the closed pore volume of 0.49 cc/g and its discharge capacity reached 438mAh/g.
[1] D. A. Stevens et al, J. Electrochem. Soc., 148 (2001) A803
[2] S.Komaba et al, ACS Appl. Mater. Interfaces, 3 (2011) 4165
[3] A. Kano et al, 228th ECS meetings, (2015) 221
(Invited) Key Challenges Facing Rechargeable Magnesium Batteries: A Peek Outside the Box
Authors: Gregory Thomas D 
Published: February 2020

Rechargeable magnesium battery science & technology has benefited from a number of advances over the past 30+ years but the still requires significant improvement before it can be considered to be a viable alternative to lithium-based batteries. In particular, cathode materials with performance characteristics that preserve the advantages of Mg (especially its high volumetric capacity, low cost, and safety characteristics) have been elusive. This talk will highlight the physical and chemical phenomena which contribute to these difficulties and discuss methods of circumventing them. Electrolytes which support the unique electrochemistry of Mg have also presented R&D challenges which will be discussed.
Intercalation cathodes have received the most attention in this field but the number of materials which have been identified that can reversibly intercalate Mg2+ ions is considerably less than the number capable of reversibly intercalating Li+. Reduced mobility and ion trapping of the more charge-dense Mg2+ions in solid structures have been identified as factors which contribute to this situation, and techniques for addressing these factors such as incorporating charge-shielding molecules including water will be discussed. Recent promising results with polyanion intercalation and organic redox cathode materials will also be reviewed. Conversion cathodes are seeing renewed interest in this area as a result of difficulties encountered with intercalation cathodes, but cell voltages with common conversion cathode materials such as sulfur are significantly lower than those attained with lithium. Performance requirements for low voltage conversion cathodes which could contribute to cells with energy densities comparable to advanced lithium-ion batteries will be reviewed along with possible strategies for implementation. Figure 1 shows active material-only specific energies which may be obtainable with possible intercalation and conversion cathodes.
Electrolytes have also proved to be challenging for rechargeable Mg batteries, and recent advances in this field will be reviewed, along with potential strategies for improving them and coupling advanced Mg electrolytes with novel cell chemistry.
References

Muldoon, J.; Bucur, C.B., Gregory, T. Quest for Nonaqueous Multivalent Secondary Batteries: Magnesium and Beyond. Chem. Rev., 2014, 114 (23), pp 11683–11720 DOI: 10.1021/cr500049y.

Bucur, C. B.; Gregory, T.; Muldoon, J. Why Grignard’s Century Old Nobel Prize Should Spark Your Curiosity. In Rechargeable Batteries; Zhang, Z., Zhang, S. S., Eds.; Green Energy and Technology; Springer International Publishing, 2015; pp 611–635.

Bucur, C.B.; Gregory, T.; Oliver, A.G.; Muldoon, J. Confession of a Magnesium Battery. J. Phys. Chem. Lett., 2015, 6 (18), pp 3578–3591 DOI: 10.1021/acs.jpclett.5b01219.

Figure 1
Organic Cathodes for Energy Storage Systems
Authors: Liao Chen , Pan Baofei , Vaughey John T. , Zhang Zhengcheng , Burrell Anthony 
Published: February 2020

Redox-active organic molecules have the potential as economical and environmentally benign cathodes for lithium ion batteries. The same concept of using organic molecules as cathodes was extended to magnesium ion batteries, however, pervious work showed considerable capacity loss upon the cycling. Furthermore, no compatible electrolytes toward both anode and cathode have been demonstrated.
Her, we have focused on several organic cathode materials as cathodes, mainly for magnesium ion batteries. For example, 2,5-dimethoxy-1,4-benzoquinone (DMBQ) was reinvestigated as a cathode material with magnesium electrolytes that are capable of plating/stripping magnesium for rechargeable magnesium-ion batteries. Two electrolytes, the magnesium bis(trifluoromethylsulfonyl)imide mixed with MgCl2 in dimethoxyethane (Mg(TFSI)2-2MgCl2 in DME) electrolyte, and the Mg(TFSI)2 in diglyme were selected. The Mg(TFSI)2-2MgCl2 in DME enabled Mg-DMBQ batteries with a discharge potentials above 2.0 V vs Mg/Mg2+, which is superior to the previous reported potential in Mg-DMBQ batteries with conventional magnesium salt-based electrolytes (1.1 V vs Mg/Mg2+ ), and also excels the well-known Chevrel phase Mo6S8 in magnesium-ion batteries (1.2 V vs Mg/Mg2+).
The other organic cathodes explored for magnesium ion batteries are the redox active polymers. With emphasis on the structure motif, several polymers were investigated as high performance cathode candidates for magnesium storage. Excellent electrochemical reversibility was established for polymers within the range of 1.5-2.0 V (vs Mg), with a 99% capacity retention in 100 cycles (104.9 mAh g-1 at 100th cycle). The superior cycling stability was further demonstrated by 1000 discharge-charge cycles with very small amount of capacity loss, highlighting the great potential of redox-active organic polymer cathodes for advanced Mg-ion batteries.

Figure 1
Magnesocene-Based Electrolytes - a New Electrolyte Class for Magnesium Batteries
Authors: Schwarz Rainer Martin , Fischer Philipp , Pejic Marijana , Marinaro Mario , Jörissen Ludwig , Wachtler Mario 
Published: February 2020

Technological evolution puts up an ever-growing demand on energy storage – challenging today’s technology. However, future needs for capacity, efficiency, availability and price on energy storage devices exceed the current state of the art technology, Lithium-ion, by far and require advanced alternative technologies. Currently, multiple alternatives are still undergoing research efforts. Magnesium batteries are a prime candidate to those future demands - magnesium is energy dense, 2205 mAhg-1, abundant and comparatively cheap. [1, 2]
Despite these promising properties, magnesium batteries still face major roadblocks until their commercialization. The favoured, high energy density, magnesium metal anode is, at the current state of research, only compatible with electrolytes based upon either magnesium-organo-halo-aluminates or magnesium-borohydrides. [3, 4] Electrolytes based upon conventional magnesium salts e.g. such as halides, perhalates or imides seem to be incompatible to the magnesium metal surface [5] where the electrolyte degenerates and forms a passivating, magnesium ion impermeable, surface layer.
Here, we would like to report on a new electrolyte system for magnesium batteries, based upon the bis(η5-cyclopentadienyl)-magnesium complex. The proposed electrolyte is highly suitable for a metallic magnesium anode. We will present the results of a comprehensive electrolyte-system characterisation, electrochemical performance testing (Figure 1), SEM and XRD analysis of the deposited magnesium, as well as IR and NMR studies on the fresh and cycled/aged electrolyte.
The presented work introduces a completely new electrolyte class for magnesium batteries.
Figure 1: Cyclic voltammogram of a 0.5 M MgCp2 in THF solution obtained at a scan rate of 10 mVs-1 in a potential range of -0.5 V to 1.2 V vs. Mg/Mg2+ for 500 cycles; WE: Cu, CE: Mg, RE: Mg.

References

[1] R. D. Shannon; Acta Cryst., 1976, A32, 751-767
[2] D. R. Lide (ed.); Section 14, Geophysics, Astronomy, and Acoustics; Abundance of Elements in the Earth's Crust and in the Sea, 85 ed., CRC Press, 2005.
[3] D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, E. Levi.; Nature, 2000, 407, 724
[4] Mohtadi, R., Matsui, M., Arthur, T. S. and Hwang, S.-J.; Angew. Chem. Int. Ed., 2012, 51, 9780
[5] O. Tutusaus, R. Mohtadi; ChemElectroChem, 2015, 2, 51-57

Acknowledgement

Funding is gratefully provided by BMBF - Project No.03EK3027C

Figure 1
High Energy Density Lithium-Sulfur Batteries for NASA and DoD Applications
Authors: Bugga Ratnakumar V , Jones Simon C. , Jones John-Paul , Pasalic Jasmina , Krause Frederick C. , Torres Loraine 
Published: February 2020

We have been successfully using Li-ion batteries in several NASA missions since 2000, including the Mars Exploration Rovers (Spirit and Opportunity), Mars Science Laboratory (MSL), Phoenix Lander, JUNO, Aquarius, Keppler Rovers and SMAP. Being compact, lightweight and durable, these batteries have contributed to a significant enhancement or even enablement of these missions. However, NASA’s future missions, e.g., Astronaut’s Portable Life Support System (PLSS) for Extra-Vehicular Activities (EVA), small planetary rovers, planetary probes, CubeSats etc., require more advanced battery technologies with higher energy densities. The lithium-sulfur system emerges as the most promising technology, because of its high theoretical specific energy (3-4x) compared to Li-ion cells. However, despite many significant developmental efforts over the last few years, Li-S technology hasn’t matured yet, mainly due to the challenges from the soluble polysulfides forming a redox shuttle and also poisoning the lithium anode. Several attempts are being reported in the literature to develop novel cathode designs, e.g., hierarchical porous carbon structures to sequester sulfur and its reduction products, and also electrolyte solutions to minimize their solubility. 1-5 Good cycle life was reported in some of these cases with nanostructured sulfur cathodes in both organic electrolytes containing suitable additives (LiNO3) and in ionic liquids, but the sulfur loadings are much lower (below 4 mg/cm2), while high loadings of >12 mg/cm2 are essential for high specific energy Li-S cells. In this context, we have developed new sulfur composite cathodes blended with transition metal sulfides (e.g., titanium and molybdenum disulfide), which not only provided adequate electronic and ionic conductivity, but also facile electrochemical activity at sulfur reduction potentials to function as redox mediators.6 With such blended cathodes, we have been able to realize high specific capacities of ≥800 mAh/g at C/3 rates with high material loadings. In this paper, we will describe the performance of these composite sulfur cathodes in different electrolytes, and also in conjunction with a polymer-protected Li anode.

Y. Yin, S. Xin, Y. Guo and L. Wan, Angew. Chem. Int. Ed. 2013, 52, 13186 (2013).

S. Evers, L. F. Nazar, Acc. Chem. Res., 46, 1135 (2013);

X. Ji, K. T. Lee, L. F. Nazar, Nat. Mater. 8, 500 (2009).

A. Manthiram, S.-H. Chung, C. Zu, Adv. Mater. 27, 1980 (2015).

S. S. Zhang, Front. Energy Res. 1, 1 (2013).

Ratnakumar Bugga, Simon Jones, Jasmina Pasalic, Dan Addison and Ramanathan Thillaiyan, 228th ECS Meeting, Phoenix, AZ, Oct. 11 (2015)
Investigating Lithium-Sulfur-Metal Interactions in the Host Materials of Li-S Batteries
Authors: Li Zhejun , Lu Yi-Chun 
Published: February 2020

Rechargeable Li-S batteries promise to provide a 2 to 3 times higher specific energy than conventional Li-ion batteries.1 The development of Li-S batteries has been strongly hindered by poor rechargeability, limited rate capability and rapid capacity fading, which largely can be attributed to the dissolution, diffusion and side reactions of soluble polysulfides in the electrolyte2. Applying host materials that can chemically bind polysulfides has been shown one of the most effective approaches in suppressing polysulfide shuttle3, which significantly improve the coulombic efficiency and the cycle life of the Li-S batteries. For instance, metal oxides such as TiO2
4, Ti4O7
5, MnO2
6have been reported effective as polysulfide immobilizers. To rationally design the host materials, it is required to understand the nature of the chemical bonding between the host materials and polysulfides and investigate key materials property that dictates the interactions.
In this work, we investigate series of transition metal oxides hosting materials for polysulfide absorption in two model electrolytes including 1,3-dioxolane (DOL):1,2-dimethoxyethane (DME) and dimethyl sulfoxide (DMSO). We apply UV-vis spectroscopy, X-ray absorption spectroscopy and X-ray photoelectron spectroscopy to understand the interactions between transition metals and various form of polysulfides (S8
2-, S6
2-, S4
2-). We further apply selected metal oxide hosting materials in Li-S batteries and characterize the effect of hosting materials in the cycling stability of Li-S batteries. We will examine the correlation between the degree of sulfur-absorption revealed by UV-vis spectroscopy and the improvement in the cycling stability of Li-S batteries. The enhancement mechanism and the nature of the bonding between the host materials and polysulfides will be discussed.

Acknowledgement:

This work is partially supported by a grant from the Research Grants Council (RGC) of the Hong Kong Special Administrative Region (HK SAR), China, under Theme-based Research Scheme through Project No. T23-407/13-N, and partially supported by a RGC project No. CUHK14200615.

Reference:

1. A. Manthiram, Y. Fu, S.-H. Chung, C. Zu and Y.-S. Su, Chem. Rev., 114, 11751 (2014).
2. M. Wild, L. O'Neill, T. Zhang, R. Purkayastha, G. Minton, M. Marinescu and G. Offer, Energy Environ. Sci., 8, 3477 (2015).
3. Q. Pang, X. Liang, C. Y. Kwok and L. F. Nazar, J. Electrochem. Soc., 162, A2567 (2015).
4. S. Evers, T. Yim and L. F. Nazar, J. Phys. Chem. C, 116, 19653 (2012).
5. Q. Pang, D. Kundu, M. Cuisinier and L. F. Nazar, Nat. Commun., 5, 4759 (2014).
6. X. Liang, C. Hart, Q. Pang, A. Garsuch, T. Weiss and L. F. Nazar, Nat. Commun., 6, 5682 (2015).