bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Redox Mediators and Water Content on Oxygen Evolution for Li-Air Batteries
Authors: Petrucco Enrico A. 
Published: February 2020

Chemistries that can demonstrate tolerance to both moisture and atmospheric carbon dioxide have the power to advance the technology readiness level of non-aqueous lithium air batteries. Previously published results have found that lithium iodide as redox mediator in dimethoxyethane solvent containing high water content affords reversible cycling of a lithium oxygen battery via lithium hydroxide[1]. In collaboration with the authors of the previous work, this concept has been extended to explore additional redox mediators and alternative electrolyte mixtures. Quantitative oxygen evolution for the new chemistries was studied using continuous differential electrochemical mass spectroscopy. Oxygen evolution was found for some of the new chemistries employed. Faradaic efficiency for oxygen evolution and Tafel analysis shows complex behaviour. Discharge product analysis shows that some of the new chemistries which afford oxygen evolution also cycle via lithium hydroxide.
[1] Liu, et al. Science, 2015, 350, 6260, p530.
Pouch Type Cells for Practical Evaluation and Application of Large-Scale Li-Air Batteries
Authors: Kwak Won-Jin , Shin Hyeon-Ji , Aurbach Doron , Sun Yang-Kook 
Published: February 2020

Thanks to high theoretical specific capacity and energy density, Li-air batteries are considered as candidates for next-generation battery systems in place of conventional Li-ion batteries for advanced applications such as electric vehicles (EV).1-3 However, low energy efficiency, poor cycle life and Li-metal safety issues make the use of Li-air batteries yet impractical. In addition, actual cell capacities are very low and, since only small-scale electrodes are currently tested, it is hard to predict the properties of large-size electrodes and cells, thus evaluating and judging real practical challenges related to this battery technology.
Here, we report on fabrication, operation and evaluation of pouch-type Li-air cells using 3×5 cm2 sized electrodes, in which we intend deal with higher capacity (mAh) of the electrodes, compared to most previous studies in the field. With the relatively large-sized cells, operating at high current density and capacity, we could recognize some remarkable problems that may not be significant in small cells.
In relatively large cells as those explored in this work issues related to non-uniform current distribution, mechanical and electronic integrity of electrodes are much more influencing compared to small cells. Hence, problems such as lithium dendrites formation and non-uniform deposition of oxygen reduction product become severe.
This study can help to determine which parameters are the most important for developing practical Li-air batteries.

References

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2. H. G. Jung, J. Hassoun, J. B. Park, Y. K. Sun, B. Scrosati, Nature Chemistry
2012, 4, 579. 3.
3 M. M. O. Thotiyl, S. A. Freunberger, Z. Peng, Y. Chen, Z. Liu, P. G. Bruce, Nature Materials
2013, 12, 1050.
Effect of Water on the Product Distribution at the Cathode of Li-O2 Batteries
Authors: Tomita Kentaro , Noguchi Hidenori , Uosaki Kohei 
Published: February 2020

Li-O2 secondary batteries are attracting much researcher’s attentions as a candidate for the post lithium-ion secondary batteries due to the superior theoretical energy capacity. Oxygen reduction reaction forming Li2O2 deposition takes place at the cathode of Li-O2 secondary batteries during the discharge process. The theoretical capacity of the Li2O2 electrode (8 kWh L-1) is comparable to the energy density of diesel fuel (9.7 kWh L-1). However, the mechanisms of the cathode reactions are complicated and are not well understood. The trace amount of water in electrolyte solutions is known to affect the reaction mechanisms1,2 but how water affect the reactions are still under discussions.
In this study, the effects of trace amount of water on the discharge product at gold electrode in the DMSO-based electrolyte solution are studied by using electrochemical quartz crystal microbalance (EQCM), rotating ring-disk electrode (RRDE) method, in situ surface enhanced Raman scattering (SERS) spectroscopy and other instrumental analysis. In situ SERS showed that ca.1000 ppm of water results in the decrease of crystal Li2O2 signal intensity and new peaks of LiHO2 and H2O2 at the initial stage of the discharge process. Application of negative potential, which causes surface mediated electrochemical reduction of LiO2 in the anhydrous electrolyte solution,3 results in the decomposition of DMSO forming Li2SO4 while amorphous phase of Li2O2 was formed in the anhydrous electrolyte solution. The series of decomposition reactions of DMSO induced by water clearly indicated by EQCM measurement as M/z = 55 g mol-1 corresponding to the formation of 1 mol of Li2SO4 by consumption of 2 mol of electron. These results show that effects of water should be considered when developing the better battery system utilizing water to change morphology of Li2O2 or converting Li2O2 to LiOH.1,2

References
(1) D. G. Kwabi, T. P. Batcho, S. Feng, L. Giordano, C. V. Thompson and Y. Shao-Horn, Physical Chemistry Chemical Physics, 18, 24944 (2016).
(2) F. Li, S. Wu, D. Li, T. Zhang, P. He, A. Yamada and H. Zhou, Nature Communications,
6, 7843 (2015).
(3) D. G. Kwabi, M. Tułodziecki, N. Pour, D. M. Itkis, C. V. Thompson and Y. Shao-Horn, Journal of Physical Chemistry Letters,
7, 1204 (2016).
Battery Functionality and Reactivity of a Cathode for Magnesium Ion Battery
Authors: Suto Koji , Zhang Ruigang , Mohtadi Rana 
Published: February 2020

Post lithium ion battery is highly demanding energy storage for smaller scale as stationary use to greater scale as grid storage, and vehicle use as well. Magnesium ion battery with metal magnesium as an anode has been investigated over decades because of its high theoretical capacity of magnesium (3833 mAh cm3) and relatively lower potential (0.7 V vs lithium) for naturally abundant mineral resources in “multivalent” metals with less risk on forming dendritic deposits [1]. After over a decade of finding of stable and reversible electrolyte based on Grignard agent such as APC [2], our finding of magnesium monocarborane [3] opened next door toward high energy density by its wider potential window up to 3.7 V and high current density more than 1mS cm-1, without corrosive issue which is intrinsic to conventional electrolytes containing chlorine.
Although of many efforts for electrolytes and electrodes, the battery system has lack of cathode capable of providing high potential and / or capacity with stable performance over numbers of cycles in charge and discharge, to takeover Li ion battery. Recently some challenges proved custom approach for magnesium ion effective to certain extent; eg. C60 [4] works as a mimic of cluster aspect of highly reversible Chevrel Mo6S8, and spinel Ti2S4 [5] presents the design of host framework with “soft” anion and ionic path.
In this study we approach to new insights into active materials by means of charge transfer. Interfacial analysis such as electrochemical impedance, XPS, etc., to the most established cathode, Chevrel phase Mo6S8 [1] in contact with MMC electrolyte gives some key factors of highly reversible cathode. Besides, our new approach for a cathode active material and its battery performance will be introduced for the next step of the reaction design.
References:
[1] J. Muldoon, C. B. Bucur, and Th. Gregory, Chem. Rev.
2014,
114, 11683.
[2] D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, E. Levi, Nature
2000, 407, 724.
[3] O. Tutusaus, R. Mohtadi, T. S. Arthur, F. Mizuno, E. G. Nelson, Y. V. Sevryugina, Angew. Chem. Int. Ed.
2015, 54, 7900.
[4] R. Zhang, F. Mizuno, L. Chen,, Chem. Commn..
2015, 51, 1108.
[5] X. Sum, P. Bonnick, V. Duffort, M. Liu, Z. Rong, K. A. Persson, G. Ceder, an L. F. Nazer, Energy Environ. Sci.
2016, 9, 2273.
Molecular Design of Conjugated Lithium Carboxylates As Negative Electrodes for Lithium-Ion Battery
Authors: Thiam Amadou , Toumieux Sylvestre , Frayret Christine , Becuwe Matthieu 
Published: February 2020

During the last twenty-five years Lithium Ion Batteries (LIBs) have expanded their landscape in large-scale applications and are now well positioned to achieve the Electrical Vehicle (EV) horizon, thus lessening our dependence towards fossil fuels. Among all possible negative electrode materials used in commercial LIBs, graphite is the most employed due to its lowest operating potential and to its excellent cyclability. However, such an operating potential (~ 0.1 V vs. Li+/Li) induces considerable risk of decomposition associated with lithium dendrite growth. Coupling many advantages in one material, conjugated lithium carboxylates can be seen as one of the best alternative to overcome these issues and thus became serious candidates to supplant LTO in the future. However, employment of organic material remains at an early stage compared with classical anode materials. A step forward deep structure-property relationship has clearly to be performed to reach the target of sustainable energy storage. The main difficulty of such approach nests in the combination of different fields, e.g. organic synthesis, material science and solid-state electrochemistry, all of them having an impact on the performances (e.g.material particle size on activity/conductivity or electrolyte on capacity. Nevertheless, electrochemical activity remains primarily governed by the molecular structure which is the starting point of the electrode material conception. As an example of the importance of molecular design on electrode performances, we first studied the impact on the rate capability of the stabilization center using naphthalene (Fédèle et al., JES, 2014) and perylene Fédèle et al., J. Mat. Chem. A, 2014) cores and very recently the incidence of the conjugation distance between two carboxylates using a layered material based on a 4,4’-biphenyl unit (Fédèle et al., Chem. Mater., accepted).
In order to explore in details the impact of the delocalization extent on electrochemical performances of conjugated dilithium carboxylate, we focused on substituted or bridged biphenyl-based materials using a coupled theoretical/experimental approach. Thanks to these investigations, we clearly showed a dramatic influence of key structural parameters modulating (or tuning) the electron movement ability and define new trends to control the redox potential, reversibility and rate capability by adding selectively atoms on the aromatic backbone. This work thus opens new perspectives towards the understanding of the reactivity of such family.

Figure 1
Effect of Material Anisotropy on the Mechanical Response of Protective Layers for Lithium Metal Anodes
Authors: Chadwick Alexander F. , Thornton Katsuyo 
Published: February 2020

A critical challenge in the development of safe, long-lasting secondary batteries with lithium metal anodes is protecting the surface of the anode to prevent dendrite formation during charging1 or to minimize interactions between the anode and active species in the electrolyte.2,3 One approach is to place a protective layer in the cell, such as a coating on the anode itself or as a free-standing membrane material, which can inhibit many of the mechanisms that lead to failure of the lithium metal anode. These layers must be mechanically robust such that they do not fail over the course of many cycles. However, these materials experience stress during cycling, which can lead to mechanical failure at high current densities. While such phenomena have been examined in certain cathode materials, such as LiCoO2,4 it has yet to be investigated in depth for anode protective layers. The stress arises from gradients in the lithium concentration that lead to the formation of eigenstrains. Here, we present a continuum-scale model to examine the effect of anisotropy in mechanical and transport properties on eigenstrains in protective layer materials. The model solves for the mechanical equilibrium of the layer, with the anisotropic linear elasticity tensor as well as the concentration-dependent anisotropic eigenstrain in the material based on the steady-state concentration profile. The von Mises stress is calculated as a function of the anisotropic properties and applied current. This stress can be compared to the yield stress of the protective layer material to determine whether it is sufficiently robust for many charge/discharge cycles of the lithium metal anode. The presented work will cover a range of cases from single-crystal domains to polycrystalline films with varying levels of anisotropy. By examining the peak von Mises stress as a function of the applied current density, the model will predict design guidelines for the relevant material parameters.

References

1. Y. Cao, X. Meng, and J. W. Elam, ChemElectroChem, 3, 858–863 (2016).
2. R. Cao, W. Xu, D. Lv, J. Xiao, and J.-G. Zhang, Adv. Energy Mater., 5, 1402273 (2015).
3. S. E. Doris, A. L. Ward, P. D. Frischmann, L. Li, and B. A. Helms, J. Mater. Chem. A, 4, 16946–16952 (2016).
4. H. Wang, Y.-I. Jang, B. Huang, D. R. Sadoway, and Y.-M. Chiang, J. Electrochem. Soc., 146, 473–480 (1999).
Electroactive Materials Design Strategies Toward Increased Electrical Conductivity: Impact on Electrochemistry
Authors: Marschilok Amy C , Takeuchi Esther S , Takeuchi Kenneth J 
Published: February 2020

Energy storage materials remain important due to their ability to store electricity for many applications including aerospace, transportation, portable electronics, and biomedical devices. Full utilization of materials requires fast transport of both ions and electrons to all regions of the electrode. Several approaches have been utilized to facilitate ion diffusion including dimension reduction, morphology control, and synthesis of layered and tunneled structures, however, electron access must also be considered. Low electrical conductivity can limit active material utilization, especially at high rates, and may be a cause of capacity fade.
One approach to address the low electrical conductivity of cathode materials is to utilize composite electrodes that contain conductive media, most often carbon. While commonly employed, this strategy is imperfect, as inhomogeneous dispersion of the active material in the conductive additive results in incomplete electrical contact to all particles in the electrode. Encapsulation of individual active material particles with a carbon coating can be more effective for providing electrical contact to each particle, however have the disadvantages of additional synthesis steps and increased production cost. An alternative strategy to approach an ideal electrode that we have been exploring is the use of bimetallic material systems. In this approach, the active material particles are electrically connected as they generate a conductive network in-situ on initiation of reduction. Bimetallic cathode materials offer the opportunity for conductive matrix formation via reduction displacement reactions that result in the formation of metal nanoparticles providing the electrical connections.
The investigation of bimetallic materials and the formation of electrically conductive pathways has included exploration of metal oxide and metal polyanion type structures including phosphate and diphosphate moieties. Additionally, composites containing bimetallic materials have been explored. The impact of this strategy on delivered capacity and capacity retention will be discussed.
Exceptional Lithium Intercalation Capacity of Incommensurate Graphene Foam in Rechargeable Batteries
Authors: Paronyan Tereza M. , Thapa Arjun Khumar , Sherehiy Andriy , Jasinski Jacek B. , Jangam John Samuel Dilip 
Published: February 2020

Development of high capacity Lithium battery anode materials will have a profound and direct impact on current commercial and emerging markets such as portable electronics, electric vehicles and electric grid storages.
Graphite’s capacity of intercalating lithium in rechargeable batteries is limited (theoretically, 372 mAh/g) due to low diffusion of lithium atoms within commensurately-stacked infinite graphene layers. Graphene foam with highly enriched incommensurately-stacking layers is grown using Chemical Vapor Deposition (CVD) method and applied as an active electrode in rechargeable batteries. Raman spectroscopy is used to estimate the fraction of incommensurately-stacking layers in a bulk material. ~90% incommensurate graphene foam is demonstrated up to 1540 mAh/g reversible specific capacity at 100 mA/g current density stable throughout hundred cycles with 75-100% Coulombic efficiency. C-rate testing of the electrochemical cells exhibit stability under high current densities which makes these cells feasible.
XRD, XPS and Raman analysis of graphene anodes show that lithium atoms highly intercalate within weakly interacting incommensurately-stacked graphene structure, followed by a flexible rearrangement of layers for a long-term stable cycling. We have tested several samples with various incommensurateness degree and found that specific capacity is enhanced when commensurately-stacking order of graphene layers is reduced in an anode material1. The incommensurately-stacked infinite layer graphene cab be considered as a “graphite-like” structure with weakened interplanar interaction which may exhibit exceptionally high lithium capacity of 1116 mAh/g with LiC2 stoichiometry. New intercalation model of multilayer graphene is considered, where capacity varies with N number of layers, resulting LiN+1C2N stoichiometry in which the finite layers of graphene can demonstrate higher capacity, achieving a maximum of 1674 mAh/g in bilayer configuration. An effective capacity increase over six times compared to commonly use commercial graphite battery cells promises the feasibility of the rapid development of lightweight, cost-efficient and high energy density secondary batteries.

Paronyan, T. M. et al. Incommensurate Graphene Foam as a High Capacity Lithium Intercalation Anode. Sci. Rep.
6, 39944; doi: 10.1038/srep39944 (2016).
High-Performance Rechargeable Lithium-Sulfur Dioxide Batteries Exploiting Conventional Carbonate-Based Electroyltes
Authors: Park Hyeokjun , Lim Hee-Dae , Lim Hyung Kyu , Bae Youngjoon , Kim Hyungjun , Kang Kisuk 
Published: February 2020

Shedding new light on conventional primary batteries sometimes inspires new chemistry adoptable for rechargeable batteries. Recently, a primary lithium-sulfur dioxide battery, which offers a high energy density and a long shelf-life, was successfully renewed as a promising rechargeable system exhibiting significant merits over the lithium-oxygen chemistry such as small polarization and good reversibility.1 Here, we demonstrate, for the first time, that the reversible operation of the lithium-sulfur dioxide battery is also possible exploiting conventional carbonate-based electrolytes. Even though carbonate-based electrolytes possess advantages such as high ionic conductivity and good electro/chemical stability and have thus been widely used in commercial lithium-ion batteries, they have not been used in metal–air batteries because of the occurrence of serious side reactions. The attempt to use carbonate-based electrolytes during the early development of rechargeable lithium–oxygen and sodium–oxygen batteries failed, yielding significant side reaction products; thus, appropriate charging process could not be achieved.2,3 The organic carbonate was highly vulnerable to chemical attacks by gas radicals generated during the discharge process. This finding has led to the general perception that carbonate-based electrolytes cannot be considered for metal–gas batteries. However, theoretical and experimental studies reveal that the SO2 electrochemistry is highly stable in the carbonate-based electrolytes enabling the reversible formation of Li2S2O4 in contrast to lithium-oxygen batteries. The use of the carbonate-based electrolyte leads to the remarkable enhancement of power and reversibility with much improved compatibility with lithium metal; furthermore, the optimized lithium-sulfur dioxide battery with catalysts achieves the outstanding cycle stability over 450 times with 0.2 V polarization, which is one of the highest efficiencies reported for metal-gas batteries. This study highlights the potential promise of rechargeable lithium-sulfur dioxide chemistry along with the viability of the conventional carbonate-based electrolytes in metal-gas rechargeable systems. We expect this finding to open up a further opportunity for the lithium–sulfur dioxide chemistry as a promising next-generation rechargeable battery and spur vigorous discussions on the role of the electrolyte in metal–air batteries.

Reference

Lim. H. -D. et al. Ange. Chem.
127, 9799 (2015).

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15, 3623 (2013).
Chemical, Morphological, and Structural Tuning of Tunnel Manganese Oxides for Intercalation Batteries
Authors: Byles Bryan , Pomerantseva Ekaterina 
Published: February 2020

In this work, we investigate the effect of tunnel dimension, material morphology, and structural water content on the performance of two tunnel structured manganese oxides in intercalation batteries. Tunnel manganese oxides represent an attractive family of materials for intercalation-based energy storage due to their open crystal structures consisting of well-defined structural tunnels that allow for the reversible insertion/extraction of charge-carrying ions, as well as their low cost, low environmental impact, and high electrochemical activity. Facile hydrothermal methods can be used to synthesize tunnel manganese oxides, which have the general formula AxMnO2, where “A” is a stabilizing cation present within the structural tunnels built from MnO6 octahedra.
We focus on comparing the performance of two tunnel manganese oxides with square tunnel structures, α-MnO2 (K0.11MnO2), which contains tunnels of 2x2 octahedra dimension, and todorokite MnO2 (Mg0.20MnO2), which contains tunnels of 3x3 octahedra dimensions. When tested as intercalation electrodes in Na-ion batteries, we find that the material with smaller structural tunnels, α-MnO2, achieved a higher initial capacity of 330 mAh g-1­, while todorokite MnO2, which contains larger 3x3 octahedra tunnels, achieved a capacity of 157 mAh g-1. However, the larger tunnel structure proved to be more stable in a Na-ion battery, demonstrating superior capacity retention, as well as superior rate performance. These results suggest that although smaller tunnels may initially show higher capacity, larger tunnels are preferable for superior electrochemical stability. Further, the effect of material morphology is also shown by synthesizing todorokite MnO2 with both a platelet and a nanowire morphology. In Li-ion batteries, the nanowire morphology exhibited a 30% higher capacity retention after 100 cycles, demonstrating the advantage of a nanowire morphology in terms of enhanced cycling stability. Moreover, the effect of structural water in todorokite MnO2 (0.42 H2O molecules per Mn) is discussed, elucidating the role of structural water on ion insertion of into tunnel structured materials. Lastly, we discuss the effect of controlling the electrochemical potential window used during cycling, the trade off between capacity and capacity retention, and how the stability of these materials can be improved. This work describes the role of tunnel size, ionic content, and material morphology on the behavior of tunnel manganese oxides and thus provides insight into tailoring of tunnel structured materials for intercalation batteries.