bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diagnosis Method to Detect the Incorporation of Metallic Particles in a Lithium Ion Battery
Authors: Nakajima Hironori , Kitahara Tatsumi 
Published: February 2020

Lithium ion batteries have the issue of internal short circuiting by the electrodeposition of metal at the negative electrode. This deposition follows the dissolution of metal particles incorporated into the positive electrode in manufacturing process. Thus, we have investigated the dissolution-deposition behavior of metals such as iron and copper using cyclic voltammetry and SEM/EDX. We have also addressed diagnosis method for the incorporation of the metal particles by electrochemical impedance spectroscopy.
Test cells were assembled with positive electrodes of LiCoO2 mixed with acetylene black as conductive filler and PVDF binder, electrolyte solution of ethylene carbonate (EC)/diethylcarbonate (DEC) (1:1 vol.) containing 1 M LiPF6, and negative electrodes of graphite mixed with PVDF binder. Lithium metal was used as a reference electrode.
Cyclic voltammetry was carried out with positive electrodes of iron plate and copper foil as working electrodes. Current onset potentials originating in the anodic dissolution of iron and copper were around 2.4 V and 3.6 V (vs. Li+/Li), respectively[1]. Hence those metal dissolve during charging of a cell. The anodic current for copper was larger than that for iron．
Iron particle with a diameter of 150 μm, and copper particle with a diameter of 100 μm were adhered to the positive electrode surface. The fully charged cell by 1C with the iron particle exhibited no rapid voltage drop for one week whereas the cell with the copper particle showed rapid voltage drop before full charge, resulting in the short circuit much earlier than iron in agreement with the larger anodic dissolution current shown by the cyclic voltammetry. SEM and EDX observations of the surface of the negative electrode after charging showed iron and copper depositions in torus-shape.
We also repeatedly maintained the cells with those metal particles under fully charged state (SOC:100%) for 24 hours before a discharging/charging cycle to assess the time variation of impedance spectra. As a result, we find characteristic change of the Bode plot for the negative electrode in the case of iron particles between 10-1 Hz as shown in Fig. 1. Since time variation in the impedance spectra was detected, electrochemical impedance spectroscopy is effective diagnosis method to detect the metal particle incorporation.
[1] C. Iwakura, Y. Fukumoto, H. Inoue, S. Ohashi, S. Kobayashi, H. Tada, and M. Abe, J. Power Sources, 68, pp. 301-303 (1997).
Fig. 1 Bode plots for the negative electrode (a) with and (b) without the Fe particles.

Figure 1
Determining Performance-Limiting Mechanisms in Fluorophosphate Sodium-Ion Battery Cathodes Via Transition-Metal Mixing
Authors: Matts Ian L , Dacek Stephen , Pietrzak Tomasz Karol , Malik Rahul , Ceder Gerbrand 
Published: February 2020

Motivated by the potential for new intercalation chemistries, sodium-ion batteries have received renewed interest as a possible replacement technology for lithium-ion batteries. To date, fluorophosphates, particularly Na3V2(PO4)2F3, are among the most promising sodium-ion cathodes studied. Fluorophosphates exhibit redox activity near 4V due to the strong inductive effect of phosphates and fluorine, and have been shown to reversibly cycle near their single-electron capacity of 128mAh/g, yielding energy densities close to 480Wh/kg1,2. However, efforts to further improve the capacity of these materials have achieved very little success.
This work reports on our efforts to determine the mechanism by which fluorophosphate cathodes appear to be limited to their single-electron capacity. Our method is to examine systems that decouple previously observed Na+extraction limits from redox limits. We will discuss the electrochemical characterization of novel mixed-transition metal fluorophosphate systems, from which we can conclude that fluorophosphate cathodes’ capacities are not redox-limited. We demonstrate reversible capacity exceeding the single-electron theoretical capacity during a single charge/discharge. In addition, computational examination of limiting behaviors will be elaborated on. Specifically, possible site-limiting and diffusion-limiting mechanisms in fluorophosphate cathodes will be presented.

References:
[1] R. A. Shakoor, D. H. Seo, H Kim, Y. Park, J. Kim, S. Kim, H. Gwon, S. Lee, and K. Kang. J. Mater. Chem., 22,20535–20541 (2012).
[2] K. Chihara, A. Kitajou, I. Gocheva, S. Okada, and J. Yamaki. J. Power Soources., 227, 80 – 85 (2013).
Influence of Synthesis Parameters on the Electrochemical and Interfacial Properties of Na2Ti3O7 As Anode for Na Ion Batteries
Authors: Zarrabeitia Maider , Castillo-Martínez Elizabeth , Eguía Aitor , Muñoz Márquez Miguel Ángel , López del Amo Juan Miguel , Rojo Teófilo , Casas-Cabanas Montserrat 
Published: February 2020

Sodium ion batteries (SIBs) are becoming an attractive alternative for stationary applications because of their low cost: sodium is more abundant and easier to obtain than lithium and cheaper current collectors made of aluminium instead of copper can be used.
While for cathode materials many lithium analogues can be successfully used in SIB [1], the challenge is to find alternative anode materials [2], the reasons being the impossibility of sodium insertion into graphite and the formation of a stable SEI layer (Solid Electrolyte Interphase).
Na2Ti3O7 has been reported as the oxide with the lowest sodium insertion/deinsertion voltage at 0.3 V vs . Na+/Na and a capacity close to 200 mAh/g [3], becoming a very promising anode candidate both in terms of energy density and cost. However the reported capacity retention needs to be improved [4, 5] and the formation of a stable SEI layer remains to be proved.
Here we present a study were the role of several synthesis parameters, such as the sodium source precursor and the atmosphere during the cooling process, is correlated with the electrochemical properties of the sodium titanate, in particular, with the capacity retention which has been dramatically improved [6]. The composition of the SEI layer has also been studied at different points of galvanostatic curve by means of XPS (X-ray photoelectron spectroscopy) combined in some cases with ion bombardment depth profiling.

[1] V. Palomares, M. Casas-Cabanas, E. Castillo-Martínez, M.H. Man, T. Rojo, Energy Environ. Sci., 2013, 6, 2312-2337.
[2] M. Dahbi, N. Yabuuchi, K. Kubota, S. Komaba, Phys. Chem. Chem. Phys., 2014, 16, 15007-15028.
[3] P. Senguttuvan, G. Rousse, V. Seznec, J.M. Tarascon, M.R. Palacín, Chem. Mater., 2011, 23, 4109-4111.
[4] H. Pan, X. Lu, X. Yu, Y.S. Hu, H. Li, X.Q. Yang, L. Chen, Adv. Energy Mater., 2013, 3, 1186-1194.
[5] A. Rudola, K. Saravanan, C.W Mason, P. Balaya, J. Mater. Chem.
A, 2013, 1, 2653-2662.
[6] M. Zarrabeitia, E. Castillo-Martínez, J.M López del Amo, A. Eguía-Barrio, M.A. Muñoz-Márquez, T. Rojo, M. Casas-Cabanas (submitted)
Corrosion Processes in Lithium-Sulphur Cells. Isothermal Calorimetry As Method of Their Identification
Authors: Kuzmina Elena , Kolosnitsyn Vladimir , Mochalov Sergey , Karaseva Elena , Nurgaliev Azat 
Published: February 2020

Electrochemical system of Lithium-Sulphur is very promising because of its high theoretical specific energy (2600 Wh kg-1). In addition to sulphur is cheap and available.
However the laboratory prototypes of lithium-sulphur batteries (cells) have several significant disadvantages: low practical specific energy (250-300 Wh kg-1at first cycles), high rates of self-discharge (>3% per month) and capacity fade (>0.1% per cycle) during prolong cycling.
The main reason of low practical specific energy of lithium-sulphur cells is the large shares of ballast components including greater share of an electrolyte than in lithium-ion cells.
Corrosion processes at lithium electrodes cause the high rates of self-discharge and capacity fade. It is related to the solubility of sulphur and lithium polysulphides in the electrolyte systems and their direct chemical interactions with the lithium electrodes.
S8 + 4Li -> Li2Sn + Li2Sk, k+n=8; k & n ≥ 1 (1)
Li2Sn + 2Li -> Li2Sm+Li2Sk; k+m=n, k & m ≥ 1 (2)
Traditionally the effect of different factors on the corrosion processes in lithium-sulphur cells is measured by results of prolong charge/discharge cycling: the values of charge and discharge capacities and rate of their fading during cycling. Such studies are slow because corrosion process occurs slow at the initial cycles and does not affect the results so it is hard to measure the efficiency of suggested methods to suppressed the corrosions processes.
As results show the combine method of isothermal calorimetry and galvanostatic polarisation (cycling) is very informative and convenient method to study corrosion processes in chemical power sources. This method allows us to identify corrosion processes at the initial stages of cycling and estimate their intensity.
The aim of this work is to estimate the corrosion activity of sulphur, lithium polysulphides and factors, affecting their interactions with metallic lithium, by isothermal calorimetry combined with galvanostatic polarisation.
The reported study was partially supported by RFBR, research project No 14-03-31399.
Nax(Fe,Mn)O2 Layered Oxides Used in Sodium Batteries : Structural Transformations Induced By the Electrochemical Process
Authors: Guignard Marie , Mortemard Benoit , Carlier Dany , Wattiaux Alain , Delmas Claude 
Published: February 2020

Layered sodium oxides with the formula NaxMO2 (where x is comprised between 0 and 1, M is a transition metal) have been intensively studied these last thirty years either for their unique physical properties (high thermoelectric power, superconductivity …) or with a view for their use in large sodium-ion batteries. More recently, advanced electrochemical properties of some NaxMO2 systems containing only one transition metal have been re-investigated and new complex materials with several transition metals in the MO2 layers have been synthesized and studied. In particular, systems containing non-toxic and abundant elements such as manganese and iron appear very attractive and first results in the P2-NaxMn1/2Fe1/2O2 system have showed a capacity as high as 190 mAh/g [1]. Other promising results were obtained in other compositions in manganese- and iron-based systems [2,3].
In this context, we recently studied some NaxMO2 phases used as positive electrode in Na cells with a special focus on the structural transformations and redox processes occurring during cycling in P2- and O3-Nax(Fe,Mn)O2 systems. The structures of all starting materials were determined by Rietveld refinement from powder X-Ray diffraction data. The electrochemical study was carried out in sodium batteries with a solution of NaPF6 in PC as electrolyte. For all materials, a very good reversibility of the electrochemical process was observed. In situ and ex situ X-ray powder diffraction experiments were carried out to understand better the structural transformations induced by the electrochemical (de)intercalation process. In parallel, redox processes were studied by ex situ and in situ Mössbauer spectroscopy.
[1] N. Yabuuchi, M. Kajiyama, J. Iwatate, H. Nishikawa, S. Hitomi, R. Okuyama, R. Usui, Y. Yamada, S. Komaba Nature Materials, 2012, 11, 512.
[2] J. Zhao, J. Xu, D. H. Lee, N. Dimov, Y. S. Meng, S. Okada J. Power Sources, 2014, 264, 235.
[3] D. Yuan, X. Hu, J. Qian, F. Pei, F. Wu, R. Mao, X. Ai, H. Yang, Y. Cao Electrochimica Acta, 2014, 116, 300.
Mechanistic Insights into Rechargeability and Capacity Limitations in Nonaqueous Li-O2 Batteries
Authors: McCloskey Bryan D 
Published: February 2020

Multiple directions in battery research are now being pursued in hopes of advancing beyond the specific energy limits imposed by conventional Li-ion electrode materials. For example, ‘beyond Li-ion’ battery chemistries, such as Li-O2, Li-S, and Mg-ion, are currently being explored as potential successors to Li-ion batteries given their very high theoretical specific energies; yet severe technical challenges have prohibited them from becoming a practical reality. The objective of this presentation is to provide an assessment of such challenges, in particular, instabilities of the electrolyte and cathode, and Li2O2 electronic conductivity limitations, facing the nonaqueous Li-O2 battery cathode. Results will be presented on the characterization of the Li2O2 formation mechanism and how the mechanism could be engineered to potentially alleviate problems associated with Li2O2 deposition on the cathode.
P2 Structure Sodium Manganese Oxides for Na-Ion Batteries
Authors: Billaud Juliette Marie , Singh Gurpreet , Armstrong Anthony Robert , Gonzalo Elena Candida , Roddatis Vladimir , Armand Michel , Somerville James William , Maitra Urmimala , Tapia-Ruiz Nuria , Rojo Teófilo , Bruce Peter G 
Published: February 2020

Lithium ion batteries have dominated the world of portable electronic devices over the past two decades and are making their way into the electric vehicle market due to their high energy density. However, recently sodium ion batteries have regained the interest of the scientific community due to the high and uniform abundance of sodium across the world and consequent low cost compared to lithium, making them attractive for grid storage. Various electrode materials have been studied for sodium ion batteries. Layered oxides, NaMO2, where M is one or more transition metals, represent an attractive class of cathodes for Na batteries. Here we show that Na0.67MnO2 with the P2 structure, Figure 1 a), exhibits a high capacity (175 mAhg-1), close to the best reported for a Na cathode, and with good capacity retention, in contrast to previous studies of Na0.67MnO2 where the capacity faded rapidly. [1] Due to the presence of Jahn–Teller active Mn3+ in Na0.67MnO2, the structure undergoes various structural transitions during sodiation/desodiation leading to many voltage steps in the charge/discharge profile. [2], [3] We have investigated reducing the phase transitions by substituting Mn3+ ions with electrochemically inactive dopant ions, which have a strong preference for octahedral sites in the layered oxide framework. This leads to the formation of a highly stable framework that shows a smooth charge/discharge profile with very low polarization even for a substitution level as low as 5%, Figure 1 b) and a capacity of ~ 175 mAhg-1. Such an observation is significant for the future development of sodium ion battery cathode materials.

References:

[1] A. Caballero, L. Hernán, J. Morales, L. Sánchez, J. Santos Peña, and M. A. G. Aranda, J. Mater. Chem., 12, 1142–1147.
[2] N. Yabuuchi, M. Kajiyama, J. Iwatate, H. Nishikawa, S. Hitomi, R. Okuyama, R. Usui, Y. Yamada, and S. Komaba, Nat. Mater., 11, 512-517.
[3] X. Wang, M. Tamaru, M. Okubo, and A. Yamada, J. Phys. Chem. C, 2013, 117, 15545.

Figure 1
Substituted Garnet Materials for Safer Lithium Ion Batteries: Composition Optimisation and Full Cell Application
Authors: Buannic Lucienne , Manalastas William Wang , Aguesse Frédéric , Han Man Huon , López del Amo Juan Miguel , Singh Gurpreet , Llordés Anna , Kilner John A. 
Published: February 2020

Solid state lithium ion conductors have been identified as very promising candidates for the replacement of liquid organic electrolytes [1]. Not only will they provide a physical barrier to Li dendrite growth but they will also obviate the use of flammable and toxic solvents. Amongst the ceramic candidates, Li7La3Zr2O12 in its cubic phase has been reported as one of the fastest lithium ion conductors (σLi+ = 0.4 mS.cm-1at 25ºC) [2]; however the stabilization of this material in the cubic phase requires high processing temperatures and long sintering times.
Our work has been dedicated to identifying suitable substitution strategies in order to stabilize the cubic phase at lower temperature while maintaining a high density for the material. In addition to studying the effect of Al substitution on the Li site, we have explored the benefits of partially replacing Li+ by Ga3+. The substitution of Li+ by a cation with higher oxidation state decreases the number of charge carriers (Li+) in the structure and could be detrimental to the conductivity of the material. Nevertheless, the preferential location of Ga3+ on the Li tetrahedral sites forces Li+ onto the distorted octahedral sites, thereby increasing the disorder on the Li sites and stabilizing the cubic phase of the garnet. This substitution leads to a considerable gain in conductivity, with values as high as 1.3 mS.cm-1 for Li6.55Ga0.150La3Zr2O12 at 25ºC [3]. Alternative substitutions on the Zr4+site will also be discussed, leading to a wider range of compositional possibilities.
In order to demonstrate the applicability of the garnet electrolytes to commercial systems, the implementation of these substituted garnets in full cell Li-ion batteries will also be reported.
[1] Knauth P. Solid State Ionics, 10, 911 (2009)
[2] Murugan, R.; Thangadurai, V.; Weppner, W. Angewandte Chemie International Edition, 46, 7778 (2007)
[3] Bernuy-Lopez, C.; Manalastas, Jr. W.; Lopez del Amo, J-M.; Aguadero, A.; Aguesse, F.; Kilner, J. A. Chemistry of Materials, 26, 3610 (2014)

Figure Caption:

(a) Crystal structure of garnet Li7-3xGax□2xLa3Zr2O12 where La (dodecahedral), Zr (octahedral) and O atoms are represented by dark red, blue, and red circles respectively. Li (octahedral), Li (tetrahedral), and Ga (tetrahedral) are represented in grey, turquoise blue, and green respectively. (b) Enlarged area of the Li vacancy highlighted in (a) showing the Li+ pathways. (c) Arrhenius plot of Li6.55Ga0.150La3Zr2O12between 340 and 180 K.

Figure 1
All Solid State Li-Ion Batteries Based on Cubic Garnets: From Material Optimization to Thin Film Battery Design
Authors: Rupp Jennifer L. M. , Ayfon Semih , Garbayo Inigo , Pfenninger Reto , Rawlence Michael , Struzik Michal 
Published: February 2020

The next generation of energy storage devices relies on a broad and adaptable range of volumetric and gravimetric energies to compete with the challenges in stationary, mobility and portable electronic electricity supply. Here, all solid state batteries based on Li-garnet-based structures are interesting model systems as these allow for complete solid state battery types that: i.) can partially use industrial waste heat to increase charging times (increased Li+ diffusion) for stationary, ii.) with new high capacity electrode materials which show conventionally a low stability in standard liquid/polymer based Li-batteries, iii.) are easy transferrable to model thin film battery structures for powering of portable electronics on chip.
Firstly, we report on Al:Li7-2xLa3Zr2O12 bulk pellet and thin film processing, their crystallization and ionic transport characteristics. Secondly, from a materials processing perspective we report on a new modified sol-gel synthesis-combustion method to lower the nano-particle production of the solids to ~ 600°C. Here, we exemplify stable electrolyte compounds based on Li7-3x(Gax)La3Zr2O12. Thirdly, for N-site doping Li7-xLa3Zr2-xTexO12 with x = 0.25 to 0.35 were prepared by synthesis in solid state, and Te is studied as alternative to Ga and Al stabilizers as battery electrolyte without grain boundary stabilization.
Finally, we concluded on the suitability of these new materials for scaling down to thin film microstructures, as potential Li-garnet electrolytes in all solid state batteries for portable electronic applications. First strategies on how to design optimum thin film-microbatteries adaptable to chemo-mechanical variations during operation will be shown. Here, two different model designs are described: (i.) the fabrication of microbattery dot arrays and (ii.) wrapped anode/electrolyte/cathode microstructures with tunable strain.
Radiation-Grafted Anion-Exchange Polymer Electrolytes for Clean Energy Applications
Authors: Ponce Gonzalez Julia , Willson Terry , Poynton Simon , Murphy Sam , Slade Robert CT , Whelligan Daniel , Hamerton Ian , Varcoe John 
Published: February 2020

Anion-exchange polymer electrolyte materials are being developed and studied for an increasing diversity of clean energy technologies, such as alkaline polymer electrolyte fuel cells, redox flow batteries, biological fuel cells, and reverse electrodialysis cells. These technologies include the application of the anion-exchange polymer electrolytes in conditions that span the pH range from highly acidic, through more neutral environments, and finally to highly alkaline.
This presentation will highlight the versatility of the radiation-grafting methodology in that it allows the production of polymer electrolytes containing numerous different morphologies and chemistries, including both cation-exchange and anion-exchange types. Once initial (small scale) experiments have been conducted and synthesis protocols have been developed, this methodology has the advantage that reasonably large (for lab-scale) quantities of materials can be synthesised, e.g. 10 – 100s of grams and several m2 sized batches, with excellent repeatabilities; this also allows for a large number of tests and experiments to be conducted on the same batch of material. This synthesis platform therefore facilitates research into such materials including research that compares ion-exchange materials where a single variable has varied: e.g. anion-exchange polymer electrolyte materials with the same ion-exchange capacities and polymer backbones but where the chemistries of the cationic head-groups is varied, anion-exchange polymer electrolyte materials with the same ion-exchange capacities and cationic head-groups but where the polymer backbones are varied, or anion-exchange polymer electrolyte materials with the same polymer backbone and head-group chemistries but where the ion-exchange capacity is varied.
The materials to be discussed include radiation-grafted anion-exchange membranes (with similar ion-exchange capacities) that possess an array of cationic head-group chemistries, including the benchmark benzyltrimethylammonium, benzyltriethylammonium, benzylimidazoliums, benzylpyridiniums, benzylpiperidiniums, and benzylmorpholinium. Some of these anion-exchange polymer electrolytes have reasonable stabilities at alkaline pHs (e.g. for use in alkaline polymer electrolytes fuel cells), whilst others can only be applied to systems where the pHs, that the materials are exposed to, are more neutral (e.g. materials for use in reverse electrodialysis cells). The ionic conductivities of these materials appear to be high enough for use in the above mentioned technologies.
As a small aside, it will also be demonstrated that cation-exchange membranes with different chemistries can also be synthesised and this is of interest to applications such as the more well-known proton-exchange membrane fuel cells as well as reverese electrodialysis.

Figure 1