bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Iron Sulfate Based Compounds as Positive Electrode Materials for Li-Ion Batteries
Authors: Rousse Gwenaelle , Lander Laura , Reynaud Marine , Tarascon Jean-Marie 
Published: February 2020

Electrochemical storage has become an integral part of our mobile society and great hopes are being placed in Li-ion batteries to meet future demands dictated by the upcoming electric vehicle (EV) and grid application markets. Batteries with greater autonomy and built from materials having minimal environmental footprint need to be developed. This calls for both innovative chemistry and new concepts. Currently battery researchers are turning their attention to the design of polyanionic electrodes made of abundant elements. Sulfate chemistry has been a fertile ground with the recent discovery of many sulfates compounds such as AMSO4
X (A = Li, Na, K; M = Fe, Mn, Ni, Co; X = F, OH).1 Among them, the triplite form of LiFeSO4F presents an electrochemical activity at 3.9 V vs. Li+/Li, with a decent capacity. Inspired by minerals,2 we also reported a fluorine-free sulphate compound Li2Fe(SO4)2, whose structure was solved from powder diffraction data: the monoclinic marinite structure is built upon FeO6 octahedron and SO4 tetrahedron forming an open framework into which lithium ions can move. The redox voltage of Li2Fe(SO4)2 competes with the one of triplite: 3.83 V vs. Li+/Li.3

In this talk, we will report on a new polymorph of Li2Fe(SO4)2, whose structure is orthorhombic (Figure 1). This polymorph can be prepared at room temperature via a ball-milling route, and it transforms into the marinite monoclinic form on heating. This new form is also electrochemically active via two plateaus located at 3.85 V and 3.73 V vs. Li+/Li, as it will be reported in a publication we have submitted very recently. Although the capacity displayed by these sulfates is too low to be implemented in real applications, these materials constitute model compounds to understand the interplay between redox voltage and structural arrangement. They also give hints about the feasibility of using high-voltage Fe-based compounds as positive electrodes in secondary Li-ion batteries. Lastly, we will mention how and why these compounds, which wereinitially studied for their performances as electrode materials, can also be interesting for their physical properties, especially for the magnetic ones that we studied from neutron powder diffraction.4

1. Rousse, G. & Tarascon, J. M. Sulfate-Based Polyanionic Compounds for Li-Ion Batteries: Synthesis, Crystal Chemistry, and Electrochemistry Aspects. Chem. Mater.130919065413003 (2013). doi:10.1021/cm4022358
2. Reynaud, M. et al. Design of new electrode materials for Li-ion and Na-ion batteries from the Bloedite mineral Na2Mg(SO4)2•4H2O. J. Mater Chem A, asap (2014).
3. Reynaud, M. et al. Li2Fe(SO4)2 as a 3.83V positive electrode material. Electrochem. Commun.
21,77–80 (2012).
4. Reynaud, M., Rousse, G., Chotard, J. N., Rodriguez-Carvajal, J. & Tarascon, J. M. Marinite Li2M(SO4)2 (M = Co, Fe, Mn) and Li1Fe(SO4)2: model compounds for super−super exchange magnetic interactions. Inorg. Chem.
52, 10456–10466 (2013).
3D Nanostructured Binder Free Electrodes for Novel Energy Storage Devices
Authors: Zhou Haitao , Wang Xuehang , Sheridan Edel , Chen De 
Published: February 2020

Energy-storage technologies, including supercapacitors with high power density and rechargeable batteries with high energy density, have attracted significant attention for applications in electric vehicles, power line conditioners, and load leveling of solar energy and wind power. However, for such applications, the demand for both high power density and energy density devices is becoming increasingly important. Thus, novel hybrid energy storage devices combining the advantages of supercapacitors and batteries is becoming a hotstopic in the energy storage research field. In previous work, the 3D nanostructured binder free electrodes have been shown to deliver high discharge capacity and excellent rate capability, which were assessed using Li-ion half cells [1-4], indicating that energy storage devices with high energy and power density may be achieved using such kinds of 3D electrodes. In this work, novel Li-ion full cells and supercapacitors were designed and fabricated using MnOx-based 3D electrodes, a manganese oxides based Li-ion full cell is shown in Figure 1a-c. The electrochemical performances of the different energy storage devices were assessed using a 3-electrode cell, as shown in Figure 1 d-f. The maximum energy density of the manganese oxides based Li-ion full cell is 223 Wh/kg at 146 W/kg. The Sn and Si based 3D anodes were also prepared and assessed using both Li-ion half cells and Li-ion full cells.

Figure 1 (a)
Figure 1 (b)
Figure 1 (c)

Figure 1 (d)
Figure 1 (e)

Figure 1: (a) Scheme of the manganese oxides based Li-ion full cell. S(T)EM images of the nanostructured LiMn2O4 cathode material (b) and the 3D C/MnOy/ACNTs anode materials (c). Two- and three-electrode charge (d) and discharge (e) voltage profiles of the manganese oxides based Li-ion full cell utilizing Li metal reference.
References
[1] Lou, F. et al. (2013) Journal of Materials Chemistry A, 1 (11), 3757-3767.
[2] Lou, F. et al. (2013) Journal of Energy Chemistry, 22 (1), 78-86.
[3] Lou, F. et al. Chemsuschem, accepted
[4] Zhou, H. et al. (2013) Nanotechnology, 24 (43), art. no. 435703.
Cycling Stability of Flexible Positive Electrodes for Li-Ion Batteries Using Nano-Fibrillated Cellulose As a Binder
Authors: Lu Huiran , Behm Mårten , Cornell Ann , Leijonmarck Simon , Lindbergh Göran 
Published: February 2020

Li-ion batteries are the most important power source in the application of portable electronics. Flexible Li-ion batteries attract increasing interest and could be very useful in bendable and wearable electronic devices. Nano-fibrillated cellulose (NFC), a renewable material, is a promising candidate as a binder for flexible Li-ion batteries, with good mechanical properties. They can be produced using a water-based paper making process, avoiding the use of toxic solvents. Recent work has shown capacity fading during repeated cycling of the paper based Li-ion batteries, and the traces of moisture in the NFC may be the cause for this degradation[i],[ii]. In the present work, the cycling stability of flexible positive electrodes (Fig. 1) for Li-ion batteries using NFC as a binder is investigated and discussed as function of electrode drying conditions, mainly the time and temperature. Preliminary results show that the cells with longer drying time of the NFC-based electrode obtains a better cycling performance at C/10, as well as a higher coulombic efficiency.

[i] S.Leijonmarck, et al. Flexible nano-paper-based positive electrodes for Li-ion batteries-Preparation process and properties, Nano Energy, 2013, 2, 794–800.
[ii] S.Leijonmarck, et al. Single-paper flexible Li-ion battery cells through a paper-making process based on nano-fibrillated cellulose, Journal of Materials Chemistry A, 2013, 1, 4671-4677.
Effect of F-Doping on the Cycling and Structural Stability of li[Li0.2Mn0.534 Ni0.133Co0.133]O2 Cathode for Li-Ion Batteries
Authors: Gu Haitao , Wang Ke , Xie Jingying , Xie Chaoxiang , Zhou Xinbing , Jian Dechao 
Published: February 2020

In recent studies, the layered composites with Li2MnO3 and LiMO2 have become as the promising cathode materials for lithium ion batteries due to the high capacity of around 250 mAh/g with a lower cost and better safety in comparison with LiCoO2.
In this study, a PAAM(Polyacrylamide)-assisted carbonate co-precipitation method was attempted to prepare the spherical Li[Li0.2Mn0.534 Ni0.133Co0.133]O2 cathode material. With the F-doping, the particle size of Li[Li0.2Mn0.534 Ni0.133Co0.133]O1.95F0.05 decreased, which was beneficial for the electrochemical properties. After 80cycles at 0.05C, the capacity was 259 mAh/g and the retention was 90% for Li[Li0.2Mn0.534 Ni0.133Co0.133]O1.95F0.05. After 200 cycles at 0.1C, 0.2C and 0.3C, the retention was 94%, 93% and 95%, respectively. The cycling properties was improved obviously with F-doping. From the results of synchrotron radiation XRD, the structures were changed with the temperature from the ambient temperature to 500 °C for Li[Li0.2Mn0.534 Ni0.133Co0.133]O2. But no structural changes were observed for Li[Li0.2Mn0.534 Ni0.133Co0.133]O1.95F0.05. Hence, the structural stability was improved further with F-doping.
Development of a High Temperature PEO-Based Li-O2 Battery
Authors: Balaish Moran , Ein-Eli Yair 
Published: February 2020

Li-air battery has the potential of becoming the ultimate power source among all electrochemical energy conversion and storage configurations derived from lithium chemistry. Unfortunately, current configurations, mostly based on a non-aqueous organic liquid electrolyte, suffer from numerous challenges, namely high electrolyte volatility, electrolyte decomposition, low cycle-life, low discharge rates and high discharge/charge over-potential. A very appealing Li-air configuration is obviously one which sees the use of a solid, solvent-free, electrolyte, such as those formed by combining poly(ethylene oxide), PEO, and a lithium salt. Polymer electrolytes are well known promising materials for high energy density rechargeable batteries. Polymer electrolytes poses several advantages over liquid based electrolytes systems, in terms of high chemical, thermal and electrochemical stabilities, all of those are important factors for batteries in number of applications, ranging from portable electronics to electric vehicles. However, wide use of solid polymer electrolyte is still prevented by the decay in ionic conductivity (10-7 to 10-5 S cm-1 at room temperature), resulting from low ionic mobility, high degree of polymer matrix crystallinity, and low degree of charge separation in addition to ion association. We hereby offer a new Li-air battery configuration, based on the well-investigated PEO- lithium salt electrolyte system. The Li-air battery will be comprised of a lithium metal anode, a highly Li+ conductive, oxygen permeable PEO-based, lithium polymer electrolyte and a high surface area carbon air cathode. As opposed to current lithium polymer electrolytes, which operate at room temperature and suffer from low ionic conductivity, the new proposed configuration will operate at a high temperature of 80°c. Above 70°c PEO predominantly exists in the amorphous state, thus a practically useful conductivity is easily achievable in the temperature range of 70-95°c. Our Li-air cell is discharged/ charged at high temperature, thus enabling better kinetics, resulting in high current densities and lower over-potential. The system is studied by electrochemical methods as well as spectroscopic ones.
The results of this work will contribute to the development of practically viable Li-air batteries.
Functional, Water-Soluble Binders for Improved Capacity, Rate Capability and Stability of Lithium-Sulfur Batteries
Authors: Lacey Matthew , Jeschull Fabian , Edström Kristina , Brandell Daniel 
Published: February 2020

In recent years, great strides forward have been made in increasing the practical capacity and cycle life of the lithium-sulfur system. Many of the strategies currently pursued involve optimisation of the conductive host structure, in order to maximise sulfur utilisation; coupled with some form of encapsulation of the active material, to mitigate capacity fade due to the well-explored reactions of polysulfide intermediates at the anode[1,2].
Recently, our group has investigated the use of functional polymers as binders in this system, particularly poly(ethylene oxide) (PEO)[3] and mixtures of PEO and poly(vinylpyrrolidone) (PVP)[4]. PVP has recently been similarly investigated elsewhere[5]. We have identified that a binder of 4:1 PEO:PVP can significantly improve the capacity, rate capability and stability of Li-S cells compared to conventional alternatives, e.g., PVdF. We have used galvanostatic cycling and impedance spectroscopy (IS) to determine that these improvements are most likely due to the influence of the polymer functionality on the chemistry of polysulfides in the electrolyte near the electrode surface.
These commodity polymers are inexpensive, water soluble, environmentally friendly and widely available, making them particularly interesting for mass production of Li-S cells. Through this simple approach we can demonstrate reversible capacities in excess of 1000 mAh g-1 for cathodes with total sulfur content of at least 58%.
Figure: comparison of different water-soluble binders: left) cycling of simple Li-S cells based on Super P host with 50% total sulfur loading at C/5; right) first discharge of Ketjen Black-based composites with 58% sulfur loading at C/50.
References:
[1] X. Ji, K. T. Lee, L. F. Nazar, Nat. Mater.
2009, 8, 500.
[2] X. L. Li, Y. L. Cao, W. Qi, L. V Saraf, J. Xiao, Z. M. Nie, J. Mietek, J. G. Zhang, B. Schwenzer, J. Liu, J. Mater.
Chem.
2011, 21, 16603.
[3] M. J. Lacey, F. Jeschull, K. Edström, D. Brandell, Chem. Commun.
2013, 49, 8531.
[4] M. J. Lacey, F. Jeschull, K. Edström, D. Brandell, submitted.

[5] Z. W. Seh, Q. Zhang, W. Li, G. Zheng, H. Yao, Y. Cui, Chem. Sci.
2013, 4, 3673.
Nickel(II)-1,4,8,11-Tetraazacyclotetradecane As a Single Electrolyte Component for Non-Aqueous Redox Flow Batteries
Authors: Kim Hyun-seung , Yoon Taeho , Jang Jihyun , Mun Junyoung , Hwang Hongseo , Ryu Ji Heon , Oh Seung M. 
Published: February 2020

Energy storage systems (ESSs) are required for stable electricity supply from power plants and efficient usage of generated electricity. ESSs are also needed to accommodate fluctuations in renewable energy generation. Redox flow batteries (RFBs) are considered as one of the reliable choices for ESSs.
Since 1970s, RFB technologies have been developed mainly on the basis of aqueous electroytes, which show a critical drawback; limited working voltage (< 1.23 V) due to a narrow electrochemical stability window of water.1 This constraint can, however, be relieved if electrochemical stability window is widened by deliberately controlling the composition of non-aqueous electrolyte systems.
Redox couple is the core component in non-aqueous electrolyte systems, which should satisfy at least the following requirements; (i) high working voltage, (ii) high solubility in non-aqueous solvents, (iii) stability for high couloumbic efficiency and cycle retention, and (iv) facile molecular diffusion in solutions. It must be additionally beneficial if it can be used for both catholyte and anolyte. When such a single electrolyte component is used for RFBs, the loss of redox couple by side reactions can be greatly suppressed.
A metal-multidentate complex, (nickel(II)-1,4,8,11-tetracyclotetradecane, Ni(cyclam)2+) has been tested if or not it satisfies the above requirements.
The nickel complex is reduced and oxidized at -1.78 V and 0.74 V (vs. Fc/Fc+), respectively (Fig. 1). Hence, this redox couple can be used as a single electrolyte component for non-aqueous RFBs. The expected working voltage is as high as 2.52 V, which is much larger than those for conventional aqueous RFBs. The maximum solubility is ~0.4 M at room temperature. This value is again higher than those for the conventional metal-ligand complexes (0.1 M).2 A much enlarged energy density is thus expected with this RFB since it shows larger values for both cell voltage and capacity. This redox couple also exhibits a stable cycle performances. As seen in Fig. 1, the current profiles are not changed even after 50 cycles.
Galvanostatic charge-discharge cycling is carried out in a non-flowing static cell. The coulombic efficiency is ~ 75% after 3 cycles.

References

1. M. Skyllas-Kazacos, M.H. Chakrabarti, S.A. Hajimolana, F.S. Mjalli, and M. Saleem, J
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Fig. 1
. The 1st and 50th cyclic voltammograms of Ni(cyclam)2+
Atomic-Scale Structure of Intercalated/De-Intercalated Electrode Materials in Lithium/Sodium Ion Batteries Via Aberration-Corrected Annular-Bright-Field Electron Microscopy
Authors: Gu Lin 
Published: February 2020

To satisfy ever-demanding inquires upon energy storage for applications in portable electronics, electric vehicles and smart grid etc., lithium ion batteries have been proved to be one of the ideal candidates in terms of energy density and power density. However, limited understanding for the structural evolution of electrode materials at atomic scale amid electrochemical process substantially hinders their further performance optimization. The recent success of annular-bright-field (ABF) imaging method erected on aberration-corrected scanning transmission electron microscopy (STEM) has been demonstrated to be a powerful technique to directly visualize individual light atoms, in particular the lithium ions, probing the nearly-equilibrated local structure of lithiated/delithiated electrodes under electrochemical cycling at atomic resolution. Compared to the high-angle annular-dark-field (HAADF) image, it is clearly demonstrated that not only heavy elements are revealed in ABF image, but also the atomic columns of O and Li. The ABF contrast tends to minimize the variance of the atomic number (Z) by following a Z1/3 dependency. With the unique ABF method, we have further studied possible electrochemical reaction mechanisms and detailed microstructure for (partially) lithiated/delithiated 1D-LiFePO4, 2D-LiCoO2, Li2MnO3 and 3D-Li4Ti5O12 and other lithium-based active materials with atomic resolution, which are essential for basic understanding and further performance optimization. These achievements provide new insight into the lithium/sodium storage mechanism in important cathode materials for lithium/sodium ion batteries.
References:
[1] Y. Sun, et al., Nature Commun. 4 (2013) 1870.
[2] R. Wang, et al. Adv. Energy Mater., in press.
[3] C. B. Zhu, et al. Adv. Func. Mater., in press.
[4] X. Lu, et al., Nano Lett. 12 (2012) 6192.
[5] S. Xin, et al., J. Am Chem. Soc. 134 (2012) 18510.
[6] X. Lu, et al., Adv. Mater. 24 (2012) 3233. (Editor’s Choice in Science 336 (2012) 1621.)
[7] Y. Q. Wang, et al., J. Am Chem. Soc. 134 (2012) 7874.
[8] X. Lu, et al., Energy Environ. Sci. 4 (2011) 2638.
[9] L. Gu, et al., J. Am Chem. Soc. 134 (2011) 4661.
Fluorinated High-Voltage Electrolyte: Synergetic Effect of Solvents and Additives
Authors: Xue Zheng , Hu Libo , Su Chi-Cheung , He Meinan , Zhang Zhengcheng 
Published: February 2020

High-voltage electrolytes (HVEs) for Li-ion battery refer to the electrolytes that are intrinsically stable towards oxidative decomposition on the cathode at high charging potential. To develop HVEs that are compatible with 5 V spinel LiNi0.5Mn1.5O4 (LNMO), we focus on incorporating fluorinated solvents in the electrolyte formulation. In the meantime, we also take into account the stability of such electrolytes on the anode. A combination of cathode-compatible fluorinated solvents with anode-protecting additives is envisaged to be a promising solution for a successful HVE.
A new HVE containing fluorinated carbonates was evaluated against LNMO cathode and showed excellent oxidative stability. Several additives were found to form solid-electrolyte interphase (SEI) layers that effectively prevented significant decomposition of the HVE on the graphite anode. Cell performance was evaluated at both ambient and elevated temperatures. The fluorinated HVE exhibited much improved performance compared with conventional non-fluorinated carbonate-based electrolyte especially at high temperature. Cycling results and electrochemical impedance spectroscopy (EIS) data clearly demonstrated the synergetic effect of the fluorinated solvents and the SEI forming additives.
Study on the Synthesis and Application of Core-Shell Structured Nanoparticles of Fe3O4
Authors: Chin Chun-Yi , Chou Kan-Sen 
Published: February 2020

This study addressed different materials to coat iron oxide, after using co-precipitation to synthesize. During synthesizing iron oxide, FeSO4•7H2O as a single raw material , was emphasized as a precursor salt. In advance, FeSO4•7H2O was oxidized into trivalence by using hydrogen peroxide, allocated Fe(Ⅱ)and Fe(Ⅲ) mole ratio as one to two, and synthesized ferric ferrous oxide nanoparticle by sodium hydroxide co-precipitation, which TX-100 was a protective agent to disperse uniformly.
Depend on the morphology of several nanopartical types through the processing, separation of precursor salt solution and NaOH solution in pump by adding TX-100 solution would get Fe3O4 ratio more evenly. Besides during the experiment, variety loading of NaOH and dispersant, using two- stage method to add NaOH as well, rod and particle mixure would obtain.
XRD, SQUID, HRTEM and SEM were used to analyze the particle size, uniformity, Magnetic, and Crystal structure. Also, intend to find the relation among synthesis and properties, and continue to work on electrodes for battery application to seek the optimal performance corresponded to synthesis conditions.
Preparation of Fe3O4@Ag was took AgNO3 and C6H12O6, the reductant, into Fe3O4 solution. Different mole ratio of AgNO3 and Fe3O4 were mix- coated. Through the process, surface modifier makes coating completely and uniformly. Later, same analysis entailed to Fe3O4@Ag product powder. The purpose was to examine its completely coating, thickness, and magnetism.
Nucleation and Growth of Lithium Peroxide in the Li/O2 Cell
Authors: Lau Sampson , Archer Lynden A. 
Published: February 2020

The aprotic Li–O2 battery offers a vast improvement in theoretical energy density up to ten times that of current Li-ion batteries, but still suffers from shortcomings in cell and material design. Some of these shortcomings stem from the large gap in understanding between fundamental studies and cell cycling experiments. In particular, it is known from computational studies that the solid Li2O2 discharge product is an electronic insulator, but SEM images of discharged cathodes show particles of Li2O2 much larger than what electron conduction and tunneling would allow. In addition, the shape of the discharge curves does not match the expected exponential resistance rise of a cell limited by electron tunneling.
In order to bridge Li2O2 properties with experimental observations, we developed a model in which Li2O2 forms as discrete particles on the cathode surface by using a combination of Kolmogorov’s statistical phase transformation theory and the atomistic nucleation theory. Nucleation rate was modeled according to a two-step process involving formation of a LiO2 intermediate. Despite its relative simplicity, the proposed model provides a near-quantitative description of empirically observed discharge curves (Figure 1). We find that the sudden potential drop at the end of discharge is caused by the reduction in active surface area as Li2O2 covers the cathode surface. Thus, the extra overpotential gained during discharge is the kinetic overpotential of the ORR rather than an ohmic overpotential through the Li2O2 bulk.
This model can be used as a guide for cathode and electrolyte design, by maximizing the amount of Li2O2 that can be collected for a given amount of electrochemically active surface area. One strategy is to promote the growth of larger Li2O2 particles. For cathodes, this means reducing the rate of nucleation by having a higher nucleation energy barrier or a lower concentration of active sites. For electrolytes, this means solvating the LiO2 intermediate to promote the superoxide disproportionation pathway. In principle, the general form of this model is applicable to any electrochemical cell that produces a solid passivation layer.
Figure 1: (a) Empirically observed discharge curves (symbols), compared with fit of the nucleation and growth model (lines). (b) Analysis of model parameters shows that they are independent of operating conditions.

Figure 1