bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) From liquid to Solid: Solid State Electrolytes and Post-Lithium-Ion Electrochemistry
Authors: Hintennach Andreas
Published: February 2020

Ever since the development of lithium-ion batteries the spirit of invention has mainly lead to an evolution of existing materials. With the focus on olivine and Nickel- and cobalt based materials the energy densities, power densities and ageing mechanisms could be investigated over the years and support the understanding of the underlying mechanisms of electrochemical energy storage and conversion.

With increasing numbers of cells being used in the world the need of a post Lithium-Ion technology emerges due to a limited availability of highly pristine nickel and cobalt and increasing need for recycling, environmental protection and overall energy efficiency. Nevertheless there is still an ongoing and very promising approach for e. g. novel stoichiometries of NMC materials, olivine materials, and nickel-rich materials with can significantly increase the energy density. But due to some limitation in the field of raw materials availability, accessibility, and sustainability, low-cobalt or cobalt-free materials are of very high interest, too. For example LMR (LNMO) can be an ideal candidate. Due to the very high reactivity and potential (i. e. 4.5 V) these materials require highly stable electrolytes.

Finally, lithium-sulphur can lead to a highly recyclable, environmentally friendly system. Having a silicon-based anode (> 85 % Si) included both volumetric and gravimetric energy density can mean an interesting alternative to metal-oxide based materials.

With the increased energy density, safety becomes a more and more important aspect in thermodynamic and kinetic investigations of these materials. This aspect can lead to the development of non-flammable electrolytes or solid state cells.

Solid state cells are a very different but highly promising approach. Having a solid-solid interphase between electroactive materials and electrolyte the chemicals mechanisms significantly change to solid state chemistry rather than solid-organic interphases chemistry.

All types of novel chemistries exhibit very different chemical mechanisms which require specific synthetically work, e. g. with the support of numerical simulation, for electrolytes, additives, binders, carbon materials, and even the surfaces of the electro-active materials itself. Understanding these mechanisms is essential to further improve the life-time, efficiency, and hence, the sustainability of any kind of energy storage and conversion, but batteries in particular.
(Plenary) Anion Redox in Metal Oxides
Authors: Shao-Horn Yang , Yu Yang , Charles Nenian
Published: February 2020

Traditional Li-ion positive electrodes such as layered LiTMO2 (TM = Co, Ni, Mn) store lithium ions and electrons largely by employing the cationic redox of the transition metal (TM), yielding a capacity of ~140 mAh g-1 upon charging to 4.2 VLi. Recent advances on Li-overstoichiometric layered materials Li1+x
TM
1−yO2 (TM = Ti, Ni, Co, Mn, Ru, Ir) offer considerably greater first-cycle capacities than the conventional layered materials LiMO2 with over than 200 mAh g-1.1-4 The extra capacity can only be rationalized through the activation of anionic redox in those chemistries, in addition to conventional cationic redox mechanism. However, by tuning transition metal species, researchers observed different reversibility of the anionic redox process, inducing drastically distinct capacity fade over charge and discharge. 1, 3-4 To fully utilize and harvest the extra capacity from oxygen redox process, a clear understanding the redox behavior of those materials is needed. In the past decades, there are several competing hypotheses proposed on the redox process of Li-rich layered materials5-7, but a governing anionic redox mechanism is still lacking.

In this work, we employed X-ray core-level spectroscopies, coupled with ab-initio calculations to first understand the redox processes and structural evolution of model systems exhibiting oxygen redox. Through this effort, we have presented a holistic picture of the anionic redox mechanism in the context of previously proposed redox schemes put forward by different researchers. Moreover, through leveraging the learning of the redox process of model materials, we systematically tuned the transition metal species in the metal oxygen framework in those Li-rich oxides, which allows us to pinpoint potential electronic-structure-based descriptors to capture the activation and reversibility of the anionic redox process. This study has laid the foundation for future high-throughput screening of new generation high-energy-density positive electrodes for Li-ion batteries.

References

1.Thackeray, M. M.; Johnson, C. S.; Vaughey, J. T.; Li, N.; Hackney, S. A., Journal of Materials Chemistry
2005,
15 (23), 2257-2267.

2.Sathiya, M.; Rousse, G.; Ramesha, K.; Laisa, C.; Vezin, H.; Sougrati, M. T.; Doublet, M.-L.; Foix, D.; Gonbeau, D.; Walker, W., Nature Materials
2013,
12 (9), 827-835.

3.Yabuuchi, N.; Nakayama, M.; Takeuchi, M.; Komaba, S.; Hashimoto, Y.; Mukai, T.; Shiiba, H.; Sato, K.; Kobayashi, Y.; Nakao, A., Nature Communications
2016,
7, 13814.

4.Perez, A. J.; Jacquet, Q.; Batuk, D.; Iadecola, A.; Saubanère, M.; Rousse, G.; Larcher, D.; Vezin, H.; Doublet, M.-L.; Tarascon, J.-M., Nature Energy
2017,
2 (12), 954.

5.Gent, W. E.; Lim, K.; Liang, Y.; Li, Q.; Barnes, T.; Ahn, S.-J.; Stone, K. H.; McIntire, M.; Hong, J.; Song, J. H., Nature Communications
2017,
8 (1), 2091.

6.Seo, D.-H.; Lee, J.; Urban, A.; Malik, R.; Kang, S.; Ceder, G., Nature Chemistry
2016,
8 (7), 692-697.

7.Saubanère, M.; McCalla, E.; Tarascon, J.-M.; Doublet, M.-L., Energy & Environmental Science
2016,
9 (3), 984-991.
(Invited) DFT-Assisted Solid State NMR Characterization of Defects in Vanadium Fluorophosphates As Battery Materials
Authors: Carlier Dany , Bamine Tahya , Sanz Camacho Paula , Nguyen Hoang Bao Long , Broux Thibault , Masquelier Christian , Croguennec Laurence
Published: February 2020

For energy storage, nowadays, Li-ion and Na-ion batteries are major technologies for mobility applications and also for large-scale storage of energy and their integration in the grid. In the scope of finding new positive electrode materials with improved performances, the deep understanding of the link between their structure, electronic structure and electrochemical behavior is crucial. As the presence of defects or disorder may play a critical role, a local characterization of the materials is highly required. To that extent, Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR) appeared to be a key tool. For paramagnetic materials, it allows to probe both, the local structure and the local electronic structure thanks to the Fermi contact interaction. In order to assign the signals and understand the spin transfer mechanism through the chemical bonds, we have been developed the use of ab initio calculations for some years.

Some recent studies of the characterization of defects or disorder in layered oxides or V-phosphate materials will be presented. Using MAS-NMR we showed that several phosphate materials as LiVPO4F, or Na3V2(PO4)2F3, which are promising materials for positive electrode application in Li-ion and Na-ion batteries respectively, exhibit some O-defects leading to the formation of V4+ ions locally. These V4+ ions are forming a vanadyl-type bond with the defect O, and affect the electrochemical cycling performances.
(Invited) Understanding Microstructural Deformation of Alloying Anodes for Li- and Na-Ion Batteries
Authors: Wu Nae-Lih
Published: February 2020

Charge/discharge of either Li- and Na-ion batteries in most cases is accompanied by microstructural variations of active materials in the electrodes. These microstructural changes, in turn, have significant impact on cycle life of the batteries. Knowledge of the dynamics of such deformation processes would be valuable to the development of batteries of long cycle-life. The current general understanding on such deformation processes has so far been limited to the dimensional variations. Recent development in operando imaging analytical techniques, such as in-operando transmission electron microscopy and X-ray microscopy (TXM), has offered the opportunities to directly probe the changes in interior microstructures of the active material particles. This talk presents examples of TXM analysis on alloying metal anodes pertaining to Li-ion and Na-ion batteries. Systematical description of the deformation processes for various alloying anode materials reveals complex correlations between their redox kinetics and metallurgical properties, which pave the way for better designed microstructures enabling high-performance anodes for the next generation high-energy batteries.
(Invited) Development of Silicon Anodes and Conversion-Type Cathodes for Li-Ion Batteries
Authors: Yushin Gleb
Published: February 2020

Energy density and cost of Li-ion batteries (LIBs) based on conventional intercalation compounds are closely approaching their limits. The reliance of conventional cathodes on the use of toxic metals additionally endangers health and safety of miners in developing countries. Conversion-type active materials offer an opportunity to double energy stored in LIBs, reduce their cost by the same factor, and improve cell safety. These materials may be produced from safer, cheaper and globally available resources and contribute to accelerated adoption of electric transportation. Formation of effective nanocomposites is likely a necessity for the successful commercialization of conversion-type electrodes, including silicon (Si) - based anodes, lithium sulfide (Li2S) and metal fluoride - based cathodes. I will discuss approaches taken by our laboratory to address current challenges of such materials.
(Invited) Engineered Active Material Particles from Scalable Processes
Authors: Obrovac Mark N , Zheng Lituo , Cao Yidan , Wang Jun
Published: February 2020

High performance positive and negative electrode materials can be highly engineered particles exhibiting particle coatings, functional nanostructures, core/shell designs, etc. Some engineered particles are often produced by complex methods (e.g. ALD coated positive electrode materials, SiO made by vacuum processing). However, less expensive and less complex methods are continually being developed to make complex engineered particles that are often superior to those made by more complex methods. In this presentation it will be shown how highly engineered positive and negative electrode particles can be practically made using scalable processes, such as mechanofusion and reactive gas milling. In some cases these simple processes can enable the practical synthesis of new material microstructures having improved performance compared to materials made by more complex methods.

Figure 1
Investigation of Capacity Fading on Li-Rich Layered Composite Cathode Materials for Li Ion Batteries
Authors: Fung Kuan-Zong , Tsai Shu-Yi , Chang Chia Chin , Chang Li-Fu , Huang Bo-Yuan
Published: February 2020

the capacity of Li-rich layered cathode powder was strongly affected by its particle size. By using sol-gel process, particle size of Li1.2Mn0.54Ni0.13Co0.13O2 powder obtained is around 200 nm. On the other hand, Li1.2Mn0.54Ni0.13Co0.13O2 powder synthesized by solid-state reaction method gives particle size as coarse as 1.0μm. The initial discharge capacity of sol-gel processed Li-rich cathode was 250 mAh/g. After 40 cycles, the discharge capacity from the same cathode still shows a capacity as high as 205 mAh/g. However, for cathode powder from solid-state reaction, its initial capacity was 190 mAh/g that is 24% lower than that of sol-gel processed cathode. After 40 cycles, the capacity degraded to 137 mAh/g. The enhanced capacity of sol-gel processed Li-rich cathode is attributed to its enormous surface area and short Li diffusion distance provided for electrochemical reaction to take place.

Furthermore, the TEM diffraction analysis of cycled Li[Li0.2Mn0.54Ni0.13Co0.13]O2 shows the evidence of spinel phase after cycling. It is believed that the transition from layered structure to spinel structure may also induce a large lattice distortion resulting in lattice breakdown and capacity fading. In additions, the phase transition may be caused by the redox reaction of transition metal ions through charging/discharging tests.
Synthesis, Characterization, and Electrochemical Properties of Iron-Doped Titania Nanoparticles
Authors: Clapham Jonathon , Barone Veronica , Fahlman Bradley Dean
Published: February 2020

In the search for alternative anode materials for Li-ion batteries with high power densities, titanium(IV) oxide has emerged as an attractive candidate in recent years. Pristine and Fe-doped titanium dioxide nanoparticles were synthesized using a solvothermal route employing titanium(IV) tert-butoxide and acetic acid as the capping agent. The use of acetic acid provides a scalable synthesis medium that avoids difficulties in removing the entraining agent, often encountered with longer-chain carboxylic acids. The synthesis incorporates a one-pot carbon- and copper-coating strategy designed to improve the electronic conductivity of the composites. Fe-doping and coating strategies both demonstrated improved electrochemical performance in Li-ion half-cells over extended cycling.
Preparation and Characterization of α-MnO2 Nanoplatelets/Onion like Carbon (OLC) Composite: High Capacity and Long-Cycle Life Rechargeable Sodium Ion Batteries
Authors: Palaniyandy Nithyadharseni , Modibedi Remegia Mmalewane , K. Mathe Mkhulu
Published: February 2020

Sodium ion batteries (SIBs) continue to receive a tremendous exposure due to its natural abundance (2.6 wt. %, compared to lithium (0.06%)), cost effective and similar chemical and electrochemical properties to the lithium ion batteries (LIBs). However SIBs are still suffering with low energy density and long cycle life which impedes the wide applications and its development of SIBs. These drawbacks such as higher redox potential (-2.71 V vs. SHE), higher atomic mass (23 g mol-1) and large ionic radii (1.02 Å) of sodium metal facing a challenge for the choice of the electrode materials for the SIBs. Therefore, it’s necessary to use suitable cathode materials in order to occupy the sodium ions during insertion and de-insertion process [1-2].

In this case, numerous cathode materials have been investigated for SIBs such as layered transition metal oxides, fluoride-based sulfates and phosphates, olivins, and NASICONs [3-5]. However, their electrochemical performance (specific capacity, long-term cyclability and rate capability performance) as reported is not satisfactory. Thus, the finding of suitable electrode materials is a key challenge for the development of high-performance SIBs [6].

Manganese dioxide is known for large open tunnels, which can provide interstitial spaces for Na-ion storage and transport. Also, manganese dioxide is highly abundant, low cost and environmental benign. Therefore, in this work, α-MnO2 nanoplatelets/OLC composite was explored as cathode material and has been synthesized by microwave irradiation method using electrolytic manganese oxide (EMD). The physical and chemical characterizations of materials reveal single phase, Mn valence state and its nanoplatelet morphology. The electrochemistry of the fabricated cells was examined by cyclic voltammetry, galvanostatic cycling and electrochemical impedance spectroscopy. The α-MnO2 nanoplatelets/OLC composite exhibits highly stable and better capacity retention compared to pure α-MnO2 nanoplatelets cathode materials. In this discussion, the explored detail of the material and its preparation, physical and electrochemical properties of α-MnO2 nanoplatelets and its composite cathode materials for the application of Na-ion batteries will be presented.

References:

[1] D. Su, et al., J. Mater. Chem. A, 1, 4845-4850 (2013)

[2] J. Y. Hwang, et al. Chem. Soc. Rev., 46, 3529-3614 (2017)

[3] S. Guo, et al. Angew. Chem. Int. Ed., 54, 5894-5899 (2015)

[4] Funeka P. Nkosi, et al. J. Electrochem. Soc., 164 (13), A3362-A3370 (2017)

[5] F. Yang, et al., Small Methods, 1, 1700216 (2017)

[6] D. Su, et al., Npg Asia Materials, 5, e70 (2013)
Rechargeable Aluminum Battery Cathode/Electrolyte Compatibility and Room Temperature Aluminum Deposition from Organic Solvent of AlCl3
Authors: Wen Xiaoyu , Guo Juchen
Published: February 2020

Lacking viable electrolytes is one of the fundamental obstacles preventing the realization of rechargeable aluminum batteries. To date, the only electrolytes which can enable allowing reversible Al deposition-stripping with excellent chemical and electrochemical stability are the chloroaluminate ionic liquids (ILs). However, these kind of ILs are extremely corrosive due to the high concentration of chloride. To demonstrate the importance of the cathode/electrolyte interfacial stability in emerging rechargeable aluminum (Al) batteries, chemical compatibility between vanadium(V) oxide (V2O5), a widely studied cathode material for Al batteries, and the most common chloroaluminate ionic liquid electrolyte are studied. The potential reactions between V2O5 and Lewis acidic species (Al2Cl7
-) and Lewis neutral species (AlCl4
-), respectively, and the resulting electrochemical properties are investigated with electrochemical analysis, spectroscopic characterizations including Raman and nuclear magnetic resonance (NMR) spectroscopy, supported by computational studies using methods based on density functional theory (DFT). Our studies clearly demonstrate that V2O5 reacts to both Al2Cl7
- and AlCl4
-, and the reaction mechanisms are proposed and validated. We also developed new organic electrolyte for Al deposition at room temperature based on AlCl3/g-butyrolactone (GBL) mixture in benzene. It is found that the solubility of AlCl3 in GBL can be significantly enhanced by adding benzene as diluent. Besides, the coordination structure between AlCl3 and GBL would change when the molar ratio of AlCl3/GBL increased above 1:1, which lead to the generation of active species for Al deposition.
Charge-Discharge Mechanism of All-Solid-State Batteries Using Li2RuO3-Li2so4 Positive Electrode Active Materials
Authors: Nagao Kenji , Sakuda Atsushi , Hayashi Akitoshi , Deguchi Minako , Hotehama Chie , Tsukasaki Hirofumi , Mori Shigeo , Orikasa Yuki , Yamamoto Kentaro , Uchimoto Yoshiharu , Tatsumisago Masahiro
Published: February 2020

All-solid-state batteries have attracted great attention because of their high safety owing to the use of non-flammable inorganic solid electrolytes. Solid electrolytes with an extremely high ionic conductivity have already been discovered, and therefore the discovery of new and efficient electrode materials is key for the construction of high energy density all-solid-state batteries. In the electrode layers for conventional all-solid-state batteries, mixtures composed of active material, solid electrolyte and carbon conductive additive powders are often applied to secure lithium ionic and electronic conduction pathways. Moreover, most of all-solid-state batteries reported so far comprise a thin electrode layer with a small amount of active materials and a thick electrolyte layer as the separator. Therefore, the energy density of all-solid-state batteries at the present stage is considerably lower than that of typical lithium ion batteries. To enhance the energy density of all-solid-state batteries, high capacity electrode materials should be developed and the active material content should be increased in the composite electrode layers.

With consideration to the demands and features described above, we have successfully developed a novel Li2Ru0.8S0.2O3.2 (80Li2RuO3·20Li2SO4 in mol%) positive electrode material for all-solid-state batteries. Mechanochemical treatment with Li2SO4 imparts ionic conductivity and favourable ductility to the Li2RuO3 active material. Because of the favourable formability and high electronic and ionic conductivities, we achieved the fabrication of all-solid-state cells, where the positive electrode layer was composed of the active material without any conductive additives. The all-solid-state cell using a monolithic Li2Ru0.8S0.2O3.2 positive electrode functioned as a secondary battery showing a high reversible capacity of about 270 mAh g-1. In this study, the detail charge-discharge mechanism of the Li2Ru0.8S0.2O3.2 positive electrode was investigated by XRD, TEM, XPS, and XAFS measurements.
Operando Neutron Imaging for Next-Generation Solid State Batteries: A Direct Visualization of Li-Ion Transport in Sulfide Materials
Authors: Hoeltschi Laura , Cochet Magali , Trtik Pavel , Jordy Christian , Villevieille Claire , Boillat Pierre
Published: February 2020

Li-ion all-solid-state batteries promise to enhance safety and performance compared to conventional liquid based batteries. Nevertheless, only few investigations have been carried out on the effect of the solid electrolyte’s ionic conductivity on the electrochemical performance of batteries in order to visualize non-uniform fields of transport.

Neutron Imaging (NI) is a non-intrusive technique that offers the possibility of tracking light elements such as the 6Li isotope during all phases of battery operation. Because it helps visualizing lithium’s concentration profiles, NI allows quantifying Li-ion transport and enables us to model solid state batteries. We therefore expect NI to help us explain solid state batteries’ poor rate capabilities. A reliable electrochemical cell was successfully designed and utilized for an operando test of an all-solid-state battery using PSI's high-resolution neutron imaging detector ('Neutron Microscope') at the POLDI beamline of Swiss Spallation Neutron Source SINQ (Paul Scherrer Institut). A solid state battery with a composite electrode TiS2:6Li3PS4(6LPS) and a 6Li-In alloy counter electrode have been investigated (Figure 1) and the results will be discussed.

Figure 1
Electrochemical Data Science Infrastructure for Open Battery Innovation
Authors: Massé Robert Carl , Goodall Brian , Ulery Daniel , Webb Nicholas J. , Asokan Nirmal Kumar
Published: February 2020

Despite significant investments in battery research and development, progress remains modest, with more advances made at the level of engineering rather than basic science.

Important interdisciplinary work is being done, but many projects and initiatives unfortunately lack the coordination or incentivization to have an impact beyond academic publications, and many learnings, tools and datasets remain siloed or forgotten.

The electrochemical and battery communities have data generated by experimentalists, algorithms developed by theoreticians, and the electrochemical domain expertise to solve thorny problems. However, what is missing is the common infrastructure.

Leveraging modern software and data science tools allows for many new opportunities to better equip scientists and engineers to have greater impact, but requires greater communication between the relevant stakeholders.

Our goal is to grow an ecosystem of battery innovators that tightens the feedback loop between basic science at academic institutions and applied engineering that takes place in industry to advance battery technology.

Components of this infrastructure include:

1) Open-source modeling and data analysis tools

2) Access to open datasets

3) Emergent best practices for managing data and contributing to the open-source community

We want to shorten the journey from intuition to experimental raw data to insights and intelligent decision making to solve important scientific and technological challenges.

We have already started this process by developing workflow tools for routine battery data management and analysis. Our platform parses electrochemical datasets from leading hardware vendors, and provides a user interface for recording project and testing metadata. Automated plotting and reporting are among the other available features. To date, our software handles basic cycling statistics and voltage profiles as well as more advanced tools such as differential capacity analysis. Future work will allow for custom analysis with an environment for scripting with Python.

We aim to arm aspiring electrochemical data scientists with tools that save time and energy. Beyond this, we help users increase the visibility of their work by curating a platform where new battery models and analyses can be hosted, rather than be delegated to “shelfware” after PhD students graduate and leave their former labs. Further, by hosting data sets and analysis tools, researchers benefit from greater reproducibility and transparency among labs, which helps to engender greater trust between the battery community and the broader public.

In doing so, we hope this platform will serve to accelerate battery innovation.
Investigation of the Interactions between Electrodes in Li4Ti5O12 – Based Batteries with Complementary Surface Analysis Techniques (XPS, SAM, ToF-SIMS)
Authors: Gauthier Nicolas , Courrèges Cécile , Demeaux Julien , Tessier Cécile , Martinez Hervé
Published: February 2020

Li4Ti5O12(LTO)-based negative electrode for lithium-ion batteries is of interest for electrical vehicles due to its safety, low cost and cycling stability [1]. In this study, the effect of the positive electrode on the electrochemical performances of LTO electrodes, in relation with the Solid Electrolyte Interphase (SEI) properties, has been investigated [2]. Full cells LTO/LiNi3/5Co1/5Mn1/5O2 (NMC) and LTO/LiMn2O4 (LMO) were cycled at 40°C over 100 cycles and the electrodes were analyzed by XPS, Scanning Auger Microscopy (SAM) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) after one and 100 cycles (figure 1). Moreover, LTO/LTO symmetrical cells were also analyzed in order to be free of the positive electrode impact. For each system, LTO electrodes are homogeneously covered by surface layers since the first cycle which induces an irreversible capacity loss. This latter is more important for LTO/LMO compared to LTO/NMC and LTO/LTO. Both SEI layers are composed of organic (polyethylene oxides, oxalates) and inorganic species (LiF, phosphates and fluorophosphates) but in different proportions and with different 2D and 3D spatial distributions: fluorine species are detected deeper in the electrode than organic species and in higher quantities for LTO/LMO for instance [3]. Moreover, the SEI is thicker on the LTO electrode when cycled versus LMO compared to NMC and contains small amounts of manganese, homogeneously spread over the surface and deeply inserted in the SEI, which entails an increase of the system impedance. In conclusion, a thick SEI associated with the presence of metallic species could alter the passivating role of the SEI and explain the less efficient electrochemical performance of LTO/LMO cells.

[1] Tarascon et al. Nature 2001, 414, 359–367.

[2] El Ouatani et al. Journal of The Electrochemical Society, 156(6): A468, 2009.

[3] Nicolas Gauthier et al. Journal of The Electrochemical Society, 165(13): A2925-A2934, 2018.

Figure 1
Sputter-Coated Li Electrodes for High Performance Li-S Batteries
Authors: Rikarte Jokin , Dibden James William , Carboni Marco , Ulissi Ulderico , Locke Jacob
Published: February 2020

Li-S technology stands out as a potential alternative for Li-ion batteries due to the improved energy density, particularly in applications where the specific energy density is important [1,2]. OXIS Energy is currently developing Li-S batteries that outperform other battery technologies available in the market nowadays. Among the different challenges to obtain a high-performance Li-S battery, the issues related to metallic Li electrode are a limiting factor [3]. Among others, the continuous degradation reactions on Li surface and dendrite formation result in poor cycle life and arise safety hazards. Different approaches have been proposed to overcome these effects, such as the use of additives on the electrolyte, the development of structured composite Li anode or the formation of an artificial solid electrolyte interphase (SEI) [3,4]. Direct deposition of protective coatings on the surface of Li electrodes by means of Magnetron Sputtering is an easy and potentially scalable method to successfully produce thin and homogeneous layers with upgraded properties as an artificial SEI [5]. In this work current research activities in sputter deposited coatings being developed at OXIS Energy will be described, focusing both on the deposition process of coating materials and the electrochemical response of coated electrodes.

[1] Manthiram, Arumugam, et al. "Rechargeable lithium–sulfur batteries." Chemical reviews 114.23 (2014): 11751-11787.

[2] Fotouhi, Abbas, et al. "Lithium-Sulfur Battery Technology Readiness and Applications—A Review." Energies 10.12 (2017): 1937.

[3] Cheng, Xin-Bing, Jia-Qi Huang, and Qiang Zhang. "Li metal anode in working lithium-sulfur batteries." Journal of The Electrochemical Society 165.1 (2018): A6058-A6072.

[4] Cheng, Xin‐Bing, et al. "A review of solid electrolyte interphases on lithium metal anode." Advanced Science 3.3 (2016): 1500213.

[5] Li, Juchuan, et al. "An artificial solid electrolyte interphase enables the use of a LiNi0. 5 Mn1. 5 O4 5 V cathode with conventional electrolytes." Advanced Energy Materials 3.10 (2013): 1275-1278.
(Invited) Advances and Issues in Developing Salt-Concentrated Battery Electrolytes
Authors: Yamada Atsuo
Published: February 2020

With a worldwide trend towards the efficient use of renewable energies and the rapid expansion of the electric vehicle market, the importance of rechargeable battery technologies, particularly lithium ion batteries, has steadily increased. In the past few years, a major breakthrough in electrolyte materials was achieved by simply increasing the salt concentration in suitable salt/solvent combinations, offering technical superiority in numerous figures of merit over alternative materials. This long-awaited extremely simple yet effective strategy can overcome most of the remaining hurdles limiting the present lithium ion batteries without sacrificing manufacturing efficiency, and hence, its impact is now widely felt in the scientific community, withserious potential for industrial development. I will try to provide timely and objective information that will be valuable for designing better realistic batteries, including a multi-angle analysis of their advantages and disadvantages together with future perspectives. Emphasis is placed on the pathways to address the remaining technical and scientific issues rather than re-highlighting the many technical advantages.
Novel Li4Ti5O12/Si/c-PAN Composite Anode for Lithium-Ion Batteries
Authors: Nurpeissova Arailym , Bakenov Zhumabay
Published: February 2020

Among the anode materials for Lithium-ion batteries (LIBs), LTO [1] and Si [2] are extensively studied for the use in applications which require high power. LTO is commercialized as an alternative to graphite because of its high safety and its ability to be used in high-power devices, due to the “zero strain” of the LTO spinel structure [1]. Si has many advantages when used as an anode material; however, there is a huge volume expansion that should be eliminated. As a possible solution of the stated issues, LTO-matrix might be used as a retaining material in case of the volume expansion of the Si nanoparticles. Until now, a few works on LTO/Si composite anodes were reported. Lin et al. [2] reported the LTO coated with thin film of silicon, and Chen et al. [3] prepared a composite with LTO, Si and conductive carbon. Since both LTO and Si have a low electronic conductivity, the LTO/Si system requires a conductive connecting agent/network to allow for efficient lithium ion diffusion. Cyclized polyacrylonitrile (c-PAN) is a polymer consisting of a conductive network of fused pyridine rings, and it was widely combined with silicon to form efficient composite anodes for LIBs [4]. This work describes the development of the new preparation technology of the anode composite material, which is based on LTO spinel and Si with addition of PAN, which demonstrates a synergistic positive effect on the performance of LIBs. This system is considered as promising alternative for the potential application in electric vehicles, energy storage systems for renewable energy sources and many others.

1) F. Luo, B. Liu, J. Zheng, G. Chu, et al., Nano-silicon/carbon composite anode materials towards practical application for next generation Li-ion batteries, J. Electrochem. Soc. 162(14) (2015) A2509–A2528.

2) Y. Lin, Y. Yang, Y. Lin, G. Zhao, T. Zhou, Z. Huang, Effects of amorphous silicon film on elevated-temperature cycle performance of Li4Ti5O12 for lithium ion battery, Int. J. Electrochem. Sci. 6 (2011) 5588–5596.

3) C. Chen, R. Agrawal, C. Wang, High Performance Li4Ti5O12/Si composite anodes for Li-ion batteries, Nanomaterials 5 (2015), 1469.

4) F.M. Hassan, R. Batmaz, J. Li, et al., Evidence of covalent synergy in silicon–sulfur–graphene yielding highly efficient and long-life lithium-ion batteries, Nature Comm. 6 (2015) 8597.
High Performance Silicon-Carbon Composite Powders Using Recycled Silicon from Solar Cells As Anode Material for Li-Ion Batteries
Authors: Eshraghi Nicolas , Mahmoud Abdelfattah , Vertruyen Bénédicte , Cloots Rudi , Boschini Frederic
Published: February 2020

Currently, silicon (Si) coming from the recycling of solar cells is a non-valued fraction. The principal aim of this work is the development of silicon recovered during the dismantling of solar panels as negative electrode material for Li-ion batteries. The principal technological challenge associated with the use of silicon in this type of application is to control the volume expansion during charge/discharge cycles. This drawback can be avoided through the formation of Silicon/carbon composites in which the size of the silicon particles and their dispersion is controlled [1–4].

In this research, we develop a carbon matrix system using a conducting carbon source and a reduced carbon from organic source that will incorporate the silicon particles. The recycled Si wafers are leached to remove Al and Ag. The a grinding step is performed to obtain Si particles of <200nm and then a mixed suspension of Si, an organic carbon source and the conductive carbon source is prepared. This mixture is spray-dried followed by heat treatment to generate a carbon matrix that incorporates the silicon particles

The morphology of the composite materials is analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Electrochemical performance of Si/C composites is characterized by Galvanostatic charge-discharge cycling and electrochemical impedance spectroscopy (EIS).

References:

[1] Y. Li, Electrochem. Commun. 72 (2016) 69–73.

[2] S.Y. Kim, ACS Appl. Mater. Interfaces. 8 (2016) 12109–12117.

[3] C. Paireau, Electrochim. Acta. 174 (2015) 361–368.

[4] J.L. Gómez-Cámer, J. Power Sources. 294 (2015) 128–135.
Improved High Temperature Performance By a Modified Phosphate-Coating on 5 V LiNi0.5Mn1.5O4 Cathode Materials for Li Ion Battery
Authors: Wu Zong-Han , Yang Chun-Chen
Published: February 2020

In this work, the FePO4-coated spinel LiNi0.5Mn1.5O4 cathode materials are successfully prepared by the solid-state reaction and wet precipitation method. The effect of FePO4 coating on the physical and electrochemical properties were examined by X-ray diffraction (XRD), micro-Raman spectroscopy (micro-Raman), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), C-rate and cycling tests (at 25 oC and 55 oC). The results show that FePO4 coating can greatly mitigate the dissolution of Mn ions into electrolyte from LiNi0.5Mn1.5O4, resulting in excellent cycling stability and rate capability. In all samples tested, it was found that the sample containing 1 wt.% of FePO4 coating presents the best electrochemical performance. It delivers discharge capacities of 112.05 mAh g-1 (at 25 oC) and 101.71 mAh g-1 (at 55 oC) at 1 C rate, with the corresponding capacity retention of 99.3% and 88.4% after 100 cycles. In addition, the cathode material presents a superior high discharge capacity of 104.92 mAh g-1 and 91.70 mAh g-1 at 5 C and 10 C rates, respectively. More importantly, the enhancement of electrochemical performance is related to the fact that the phosphate coating layer effectively diminishes the side reactions, which occurred at interface of the 5 V LiNi0.5Mn1.5O4 cathode and the electrolyte.

Keywords: lithium-ion batteries, spinel LiNi0.5Mn1.5O4, 5V cathode materials, FePO4-coated, high-temperature.
A High Performance All-Solid-State Lithium-Ion Battery Composited with Silicon/Carbon Anode// Li6.4La3Zr1.4Ta0.6O12/Polymer Membrane// LiFePO4/Li5FeO4 cathode
Authors: Huang Ting-Yuan , Liu Shih-Fu , Chen Han-Yi
Published: February 2020

All-solid-state lithium-ion batteries (LIBs) have many advantages over traditional LIBs including higher energy density, higher voltage endurance, intrinsic series connection, no solid electrolyte interphase (SEI) -related decay mechanism for longer life time, and the most important issue, safer than traditional LIBs. In this research, we assembled a high performance all-solid-state LIB which exhibited high energy density, good cycle stability and high safety. For the component of all-solid-state LIB, Li6.4La3Zr1.4Ta0.6O12 / polymer composited membrane was used as a solid electrolyte. This solid electrolyte exhibited good ionic conductivity thus a LIB comprised of LiFePO4//solid electrolyte//Li metal performed a well capacity of ~150 mAh/g, showing similar capacity with the LIB with liquid electrolyte. For the anode side, instead of lithium metal, silicon/carbon was used as an anode material. The ratio of silicon and carbon was optimized in order to achieve high capacity as well as good cycle stability. The cathode material in this LIB cell was LiFePO4/Li5FeO4 hybrid material which was utilized as a lithium source to compensate the irreversible capacity loss in the anode material during the first charge/discharge process. With this battery design, we successfully demonstrated a high energy-density, high cycle-stability, and high-safety all-solid-state LIB.
Enhancing the High-Voltage Cycling Stability of Nickel-Rich Oxide Cathode Using Functional Electrolyte
Authors: Tran Yen Hai Thi , Pham Hieu Quang , Kwon Young-Gil , Song Seung-Wan
Published: February 2020

Increasing needs of electric vehicles and grid-based energy storage systems for the reduction of carbon dioxide gases require higher energy density lithium (Li)-ion batteries than commercial batteries. The energy density of Li-ion batteries can increase by increasing the specific capacity of cathode material, which can increase by raising the charge cut-off voltage. Among various cathode materials, nickel-rich layered oxides of Li(Ni1
–x

–y
Co
x
Mn
y
)O2 (NCM, 1–x–y ≥ 0.5) are promising high-capacity cathode materials for high-energy density Li-ion batteries because of higher capacity and lower cost than nickel-lean oxides. However, the limited anodic instability of the conventional carbonate-based organic electrolytes at the voltage higher than 4.2 V versus Li/Li+ and instability of cathode-electrolyte interface at highly charged state makes high-voltage charge of nickel-rich oxide cathode difficult. In order to mitigate the electrolyte and interface issues, we have been developing new functional electrolytes that provides high anodic stability above 4.3 V and highly stable cathode-electrolyte interface. High-voltage electrochemical and interfacial reaction studies and their correlation to cycling performance would be discussed in the meeting.

Acknowledgements: This research was supported by Ministry of Trade, Industry & Energy (R0004645) and Creative Human Resource Development Consortium for Fusion Technology of Functional Chemical/Bio Materials of BK Plus program by Ministry of Education of Korea.
A Novel Approach for Synthesis of Nickel-Rich Layered Oxide Cathode Materials with Tailored Morphology and Their Electrochemical Performance
Authors: Siozios Vassilios , Heidbuechel Marcel , Diehl Marcel , Ruttert Mirco , Schmuch Richard , Winter Martin , Placke Tobias
Published: February 2020

The improvement in energy density of lithium ion batteries (LIBs) is primarily focused on the increase of the specific capacity of active materials and the cell voltage.[1] Transition metal (TM) oxide-based cathodes materials reach a high specific capacity through the optimization of the chemical composition with a higher Ni content and can be cycled up to 4.6 V.[2] However, the electrochemical performance of Ni-rich cathode materials depends strongly on their physical properties such as particle size, specific surface area or surface characteristics. The poor rate capability and capacity retention as well as the high first cycle irreversible capacity loss (ICL) and the low volumetric energy density of electrodes have to be improved by specific design of the particle shape. A spherical morphology with a narrow size distribution is the preferred particle shape and can only be synthesized during the co-precipitation of TM-hydroxides or -carbonates by a continuously stirred tank reactor (CSTR). Additionally, the CSTR-process allows a further improvement of the cathode materials during the synthesis of core-shell and full concentration-gradient particles.[2]

In this work, the design and the operating principle of a novel Couette-Taylor-Flow-Reactor (CTFR) is evaluated regarding the synthesis of spherical shaped Ni-rich TM-precursors. The CTFR offers a continuous process and is constructed by two co‐axial arranged cylinders with a small gap and a low working volume. The rotational motion of the inner cylinder induces a turbulent Taylor‐vortex flow. Above the suitable Taylor number (Ta), a periodic and stable turbulent fluid motion is formed, which increases the fluid shear and the local concentration of educts and promotes the agglomeration of precipitates to uniform spherical particles with narrow particle size distribution.[3]

Based on the co-precipitation of Ni-rich TM-precursors by a continuous CTFR, the influence of the reaction conditions on the properties of TM-precursor is investigated. The rotational speed, residence time, temperature and pH-value were varied in a broad range. The growth behavior of the particles, regarding the morphology, particle size distribution, tap density and chemical composition of TM-precursors as well as for lithiated cathode materials are investigated. The electrochemical properties of the corresponding cathode materials with their unique particle morphology in dependence of the co-precipitation conditions are comprehensively evaluated for finding the optimal synthesis conditions.

[1] J. Betz, G. Bieker, P. Meister, T. Placke, M. Winter, R. Schmuch, Adv. Energy Mater. 2018, 1803170/1-18.

[2] H. Li, P. Zhou, F. Liu, H. Li F. Cheng, J. Chen, Chem. Sci, DOI: 10.1039/c8sc03385d.

[3] J.-M. Kim, S.-M. Chang, J.-H. Chang, W.-S- Kim, Colloids and Surfaces A: Physicochem. Eng. Aspects (2011) 384, 31-39.
Li Buffer Interest in Silicon Based Anode to Improve Li-Ion Battery Cycle Life
Authors: Porcher Willy , Gutel Elise , Blanc Lionel , Haon Cédric , Reynier Yvan
Published: February 2020

Silicon is a promising material at the negative electrode due to its huge specific capacity and its low potential. However, this high capacity reflects huge volume changes of around 270% which cause at nanoscale solid electrolyte interphase (SEI) fracture associated with irreversible Li consumption and at microscale electrode cracks with active material loss. To achieve a suitable cycle life, many studies reports the use of silicon particles incorporated in graphite material composite. This approach is consistent with the lowest volume capacity at the positive electrode. Considering the energy density at cell level, no significant improvement is obtained with higher silicon content at the negative electrode.

However the huge specific capacity of the silicon is not only a way to improve the energy density at cell. It is also a way to implement a lithium buffer at the negative electrode without sacrificing the energy density. In a standard Li-ion cell, the active lithium content is stored within the cathode. During the first cycle a certain amount of lithium is lost by SEI formation so that the remaining lithium is reduced. Many strategies are reported to incorporate extra lithium in the anode to compensate this loss [1]. By adding much more lithium, we were able to evaluate the interest of a lithium buffer which can a priori compensate the lithium loss at the first cycle and all along the cycle life.

Usingsilicon alloy blended with graphite material, several electrodes were coated with various silicon content, loadings and porosity by keeping constant the electrode thickness. Different prelithiation levels were then studied in pouch cell using NMC622 positive electrodes. Results show that it is possible to have 90% of capacity retention at cell level after 1000 cycles at C/2, 100% DOD and 25°C.

[1]: F. Holtstiege, P. Bärmann, R. Nölle, M. Winter, T. Packle, Batteries, 2018, 4, 4.
Polyanion-Type Anode Material for Lithium-Ion Batteries
Authors: Xia Yong-Yao
Published: February 2020

Today’s anode for lithium ion batteries is dominated by graphite, with a low operate voltage at 0.1 V vs. Li+/Li, easy to format lithium dendrite and cause to safety risk. As an alternative anode material, the “zero-strain” spinel structure Li4Ti5O12 could avoid Li plating with a relative high intercalation potential (1.55 V vs. Li+/Li) and exhibits an excellent cycling stability. However, the slightly low capacity and high voltage of Li4Ti5O12 result in low energy density.

Herein, we report several polyanion-type anode materials for Li (Na)-ion Batteries (Figure 1). Figure 2 gives the crystal structure of Li2TiSiO5, which is illustrated as a layered structure with infinite sheets of distorted TiO6 octahedra and SiO4 tetrahedra, linked by Li atoms. The distorted TiO6 octahedral and SiO4 tetrahedral networks are thought to be the origin of the structural stability of this material. Figure 2 gives the typical charge/discharge curve of Li2TiSiO5 at between 0 and 3 V (vs. Li+/Li), delivers a reversible charge capacity (Li-ion extraction) of 308 mAh/g, with a voltage plateau below 1.0 V.

Fig. 1 (a) Phase diagram of polyanion-type materials. (b) Crystal structure of Li2TiSiO5 and (c) typical charge/discharge curve

References：

[1] Y-Y Xia, et al. Energy Environ. Sci. 2017,
10
, 1456-1464;

[2] Y-Y Xia, et al. Electrochim. Acta, 2018, 260, 695-702;

[3] Y-Y Xia, et al. ACS Appl. Energy Mater. 2018, doi10.1021/acsaem.8b01412.

Figure 1
Sodium Vanadium Fluorophosphates Morphology Effects on Rechargeable Sodium Ion Batteries
Authors: Wang Robin Chih-Hsing , Chiu Sheng-Cheng , Yeh Yu-Wen , Yang Chang-Chung , Chang Wen-Sheng
Published: February 2020

With growing demands of using sustainable energy, a reliable energy storage system is truly essential. Sodium ion battery is one of the candidates which features in low cost and reasonable battery performances for future energy storage. In our previous works, promising cathode material, carbon-coated sodium vanadium fluorophosphates (Na3V2(PO4)2F3/C, NVPF/C) nanocomposites with sodium superionic conductor (NASICON) structures, have been investigated and displayed high capacities at high operation voltage. Some thorny issues arising, however, during the small-scale production. First, the discharging capacities decrease as the loading of active materials increase. Second, the original synthesis method is time consuming and low yield. Considering the economic and technical feasibility, we introduce some measures to improve both the manufacture process and the battery performance. The adoption of spray-drying not only effectively reduces the production time of NVPF/C but transforms the shape of NVPF/C from blocks to spheres. In addition, different recipes of additives results in different morphology of NVPF/C particles. Here we present three types of NVPF/C, including blocks, hollow spheres and solid spheres, which are confirmed by SEM. X-ray diffraction indicated that the purity of NVPF crystalline increased by the new process. Coin cells assembled with Na foils reversible discharge capacities of 105 mAh g−1 at 1C, accompanied with high active material loading over 10 mg/cm2.