bluuebunny/crossref_metadata_2025_split huggingface dataset:
Titanium Oxide Filled Carbon Fibres for Lihium and Sodium Ion Insertion
Authors: Čech Ondřej , Vanýsek Petr , Chladil Ladislav , Částková Klára 
Published: February 2020

In this contribution, we would like to present structural and electrochemical characterization of composite carbon/TiO2 fibers prepared by centrifugal force spinning. Monoclinic TiO2-B is a very promising material with respect to lithium-ion insertion and unlike other TiO2 allotropes, TiO2-B crystallizes in monoclinic lattice with opened layered structure giving it extraordinary possibilities for lithium ion storage. Carbon fibers filled with TiO2 particles were prepared using PAN as carbon source together with the mixture of sodium trititanate Na2Ti3O7 and sodium hexatitanate Na2Ti6O13 as TiO2 source. The solution for preparation of fibers was made by dissolving PAN in DMF with dispersed hydrothermally synthesized Na2Ti3O7/Na2Ti6O13 nanorods. Fiberio Cyclone 1000M/D was used to spin the as prepared solution in the form of composite polymer/ceramic fibers which were heat treated in nitrogen atmosphere at 800°C subsequently. XRD measurements revealed that the sodium titanates were successfully transformed in the form of TiO2 with either monoclinic or tetragonal lattice. Electrochemical measurements were performed in aprotic electrolyte against metallic lithium in a three electrode setup. Cyclic voltammetry shows response typical for mixture of two crystallographic phases of TiO2 where TiO2-B is present.

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The Electrochemical Properties of Hydrothermally Self-Assembled 3D Rgo for Lithium Air Batteries
Authors: Choi Yusong , Kim Jiyoun , Jang Yoonhee , Yoo Hyeryun , Cho Janghyeon , Seo Ilsung 
Published: February 2020

The oxygen electrode is the most important part in lithium air batteries for oxygen reduction and evolution reaction (ORR/OER) in order to get closer to the theoretical energy density of 11,238 Wh/kg, which is the best among the batteries ever developed. Many carbon materials have been researched as a candidate oxygen electrode for lithium air batteries such as a carbon black, CNTs and 2D graphene. Compared to the many research results, there are still many controversies on optimum oxygen electrode for lithium air batteries. The most important properties for oxygen electrode are the microstructures such as an optimum pore size of less than 10 nm and pore size distributions which affect greatly to ORR/OER at the interface of between the electrode and electrolyte.
In this perspective, the hydrothermally self-assembled 3D RGO has great potential as an oxygen electrode. Because, it has a wide range of pore size and large surface area, as well as a high conductive network. However, 3D RGO has some obstacle to be surpassed such as side reactions which induce a large voltage gap, and decay the cycling performances. If the electrochemical reaction mechanisms of 3D RGO in lithium air batteries are well investigated clearly, the 3D RGO is a still desirable electrode for lithium air batteries. In this research, we synthesized self-assembled 3D RGO electrode by means of hydrothermal methods. The electrochemical properties and reaction mechanisms of the self assembled 3D RGO electrode were investigated using BET, EIS, SEM, XRD. As a result, we carefully assessed the possibility of 3D RGO as a game changer in lithium air batteries.
Optoelectronic and Electrochemical Properties of ZnO Based Films
Authors: Shi Qian , Lin Song sheng , Hou Hui Jun , Wei Chun bei , Li Hong , Su Yi fang , Hu Fang 
Published: February 2020

ZnO based thin films are commonly used as transparent conductive oxides (TCO). There is increasing attention paid to improving transparent conductive electrodes for applications in photovoltaic devices, displays and electronics. However, simple deposition technology with better properties than the present generation are required for new devices. In this study, ZnO based TCO films with different dopants were prepared by magnetron sputtering technique at room temperature. A relationship between the microstructure and optoelectronic properties of sputtered ZnO based films was studied.
As a potential transparent anode electrode for thin film batteries, the electrochemical behavior were further investigated. The electrochemical test show that the highest capacity of 300 mAh/g was obtained, which is higher than that of traditional graphite anode. In comparison with the resistivity results, the conductivity shows a positive effect in enhancing the specific capacity. High conductivity will provide more chance for the reaction between Li and active materials. The cycling test shows that a reversible capacity of 150 mAh/g can be achieved even after 200 cycles. The research reveals that ZnO based films with low electrical resistance are in favour of their electrochemical performance.
Preparation of Hollow Hithium Titanate Fiber Tube By Electrospinning
Authors: Wang Yudong , Gao Fei , Liu Hao , Zhang Mingjie , Geng Mengmeng , Yang Kai 
Published: February 2020

With the progress of science and technology, notebook computers, microcomputers, digital cameras, mobile phones and other new electronic equipment come out one after the other. The development of new products to the storage of energy have a greater demand, the traditional graphite anode material has been unable to meet its performance needs. The spinel lithium titanate is a lithium ion battery anode material with good cycling capability, wide operating temperature range and good safety performance. However, due to the poor electrical conductivity and low lithium-ion diffusion coefficient, the rate performance is very limited. Therefore, increasing rate performance of lithium titanate anode material becomes the only way of application of lithium titanate .
In this paper, lithium titanate is prepared by coaxial electrospinning. With the High molecular weight polymer polyvinylpyrrolidone (PVP) providing high viscosity，a solution spinning solution of PVP and absolute ethanol is used as the inner layer template solution. The Part of solution with a lithium source and a titanium source set as an outer layer precursor solution. After the titanate precursor fiber filaments are calcined, with core and outer PVP are removed the hollow lithium titanate filament is finally obtained. Figure a is cycle-capacity curve of the hollow lithium titanate anode material after prepared into a button cell. The first 0.2C rate of the specific capacity is 174.9mAhg-1 with theoretical specific capacity flat, and at the 30C specific capacity can be to 105 mAhg-1, which can achieve that Li-ion battery immediately charge. Figure b shows that, at low charge and discharge rate, lithium titanate discharge platform is relatively stable, while platform stability is poor at the high charge and discharge rate.
Figure 1. (a) Discharge capacity curves of lithium titanate at different charge and discharge rate; (b) the first discharge profiles of lithium titanate at the different charge and discharge rate.

Reference

[1] Cho, Y., Lee, S., Lee, Y., Hong, T., & Cho, J. (2011). Spinel-layered core-shell cathode materials for li-ion batteries. Advanced Energy Materials,1(5), 821–828.
[2] A. K. Moghe, & Professor B. S. Gupta. (2008). Co‐axial electrospinning for nanofiber structures: preparation and applications. Polymer Reviews,48(2), 353-377.
[3] Tong, H., Tao, X., Wu, D., Zhang, X., Li, D., & Zhang, L. (2014). Preparation and characterization of doped tio 2, nanofibers by coaxial electrospining combined with sol–gel process. Journal of Alloys & Compounds, 586(10), 274-278.

Acknowledgment

Thanks for being funded by the Technology Research Program of the State Grid about Preparing Submicron Lithium Titanate-based Materials for Energy Storage Batteries (DG71-15-042) .

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Anthraquinone Functionalized Reduced Graphene Oxide As Electrode Material for Aqueous and Non-Aqueous Rechargeable Batteries
Authors: Esat Burak , Bahceci-Sertkol Sumeyye , Momchilov Anton Angelov 
Published: February 2020

The use of electro-active organic compounds as electrode materials in rechargeable batteries has been a very active research topic due to their high theoretical capacity, availability of various redox potentials depending on the electro-active group, ease of modification of properties, and improved safety. However, the issue of solubility in electrolytes limits their applications in batteries. The most common solutions for this problem involve incorporation of these organic molecules into the insoluble polymeric structures and trapping of these inside porous carbon materials. Here, we have demonstrated the covalent attachment of anthraquinone (AQ) derivatives via nitrene chemistry onto reduced graphene oxide (RGO) as another alternative. The successful synthesis of the RGO functionalized with anthraquinone groups (RGO-AQ) and its utilization as cathode materials in Li-batteries have also been demonstrated. The cells with RGO-AQ used as cathode materials initially discharged 126 mAh/g when cycled between 1.8-3.2V at the rate of 5.35mA/g in LiPF6/ EC:DEC (1:1) electrolyte, and discharged 185.7 mAh/g when cycled between 1.3-3.6V against Li metal at the rate of 6.0 mA/g in LiClO4/ PC electrolyte. The AQ-RGO has been used also as an anode material against in an aqueous battery against NiOOH (AQ-rGO | 30% NaOH | NiOOH). This battery provided a capacity of 140 mA/h at 0.83V and displayed a very good rate capability.

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Study of Polysulfide Speciation in Lithium Sulfur Batteries Using in Situ Confocal Raman Microscopy
Authors: McBrayer Josefine , Beechem Thomas E. , Perdue Brian Robert , Garzon Fernando H , Apblett Christopher A. 
Published: February 2020

Lithium sulfur (Li-S) batteries are a promising option for high energy density applications, such as electric vehicles and grid storage. In addition to a high theoretical specific energy, the Li-S system also boasts a lower cost and the use of relatively nontoxic, abundant materials compared to current lithium ion batteries. However, soluble, mobile polysulfide intermediates in the electrolyte lead to a polysulfide shuttling mechanism resulting in damage to the anode, loss of active material, and diminished cyclability. A better understanding of the polysulfide speciation as a function of depth of discharge is warranted to identify means to mitigate the polysulfide shuttle.
In response, polysulfide speciation is examined, under relevant conditions, in an operational coin cell, at varying states of charge and position, using in situ confocal Raman microscopy. Specifically, a spectroscopic 2032 coin cell was designed for use in in situ experiments while maintaining a representative environment for discharge. The coin cell consisted of a carbon-sulfur cathode, lithium metal anode, and 1:1 1,2-dimethoxyethane to 1,3-dioxolane with 1M LiTFSI and 0.25M LiNO3electrolyte. To aid in comparison, polysulfide standards were synthesized and investigated using electrospray ionization-mass spectroscopy (ESI-MS). Raman and ESI-MS were utilized to map polysulfide speciation and relative abundances along the discharge curve. The electrolyte within the cell was probed as a function of position within the cell to determine the spatial distribution of differing polysulfide species. Challenges associated with performing Raman spectroscopy within this environment, to differentiate the varying polysulfide species in solution, were also investigated.
Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

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Approaching in-Situ Investigation of SEI Growth Dynamics By Isotope-Assisted TOF-SIMS
Authors: Lu Peng , Liu Zhe , Zhang Qinglin , Xiao Xingcheng , Chen Long-Qing 
Published: February 2020

Among the many challenges for Li-ion batteries (LIBs) to achieve long cycle life, formation of high quality solid electrolyte interphase (SEI) is of critical importance. SEI forms on LIB anode during the initial cycles, and its properties directly impact battery life and power performance. In-depth understanding of SEI growth mechanism can provide critical parameter input for modeling and simulation, set foundation for the SEI properties and performance correlation, and lead to the ultimate effective artificial SEI or coating design to achieve satisfactory cell cycle efficiency. However, due to the nm thickness and air/moisture sensitivity of SEI, designing and performing in-situ diagnostics are technically challenging. To date, most studies on SEI properties are performed on electrodes harvested after SEI formation, and the time-dependent growth mechanism of SEI during its formation remains to be elucidated.
In this talk, we will present an approximation of in-situ diagnostic method, by utilizing isotope-assisted time-of-flight secondary ion mass spectrometry (TOF-SIMS). This method is capable of obtaining time-dependent information during SEI growth, even after the growth process has completed. The model battery design includes a Cu electrode, 6Li labeled electrolyte (1M 6LiBF4 in EC:DEC 1:2) and a 7Li metal counter electrode. As SEI grows on the Cu electrode, the 6Li:7Li isotope ratio in the electrolyte decreases due to 6LiBF4 consumption. The time scale of SEI growth thus can be represented by the 6Li:7Li ratio in the SEI, and each 6Li:7Li ratio corresponds to a snapshot during SEI growth. The isotope ratio are measured with TOF-SIMS after harvesting the SEI. With this method, we have found that the SEI portion formed first (higher 6Li:7Li ratio) presents at the electrolyte/SEI interface, and the SEI formed last (lower 6Li:7Li ratio) exists at the SEI/electrode interface. These results also indicate that new SEI forms at the SEI/electrode interface. Further chemistry analyses with TOF-SIMS and XPS show that the portion formed first are mostly organic compounds while the portion formed last are mostly inorganic compounds. This method could also be applied in other fields where growth dynamics are of interest, such as investigating Li dendrite growth.

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Encapsulating of Sulfur and Acetylene Black with Manganese Dioxide Nanosheets for High-Performance Lithium–Sulfur Batteries
Authors: Walle Maru Dessie 
Published: February 2020

A novel acetylene black (AB) and sulfur composite wrapped by manganese dioxide nanosheets (MnO2@AB/S) as a cathode material for lithium-sulfur (Li-S) batteries was prepared. The MnO2@AB/S composite was first prepared by simple melt-diffusion sulfur on/into AB followed by encapsulating by the two dimensional MnO2 nanosheets. Surface modification on the sulfur and AB composite would be an efficient strategy to enhance the cycle stability and to improve the insulating nature of sulfur. The MnO2 nanosheets also increase high active contact area to improve the conductivity and stability of the cathode. The as-prepared cathode material with a high area sulfur loading of 6.19 mgcm-2 delivers a high initial discharge capacity of 994.4 mA h g-1 and the coulombic efficiency is up to 91.4% at high current rate of 1 C compared with AB/S composite. The MnO2@AB/S electrode is promising as a potential practical application for lithium-sulfur batteries.
Experimental Protocol for Magnesium Electrochemistry
Authors: Masse Robert C , Cao Guozhong 
Published: February 2020

Magnesium batteries are a compelling alternative to lithium-ion batteries on the basis of safety, resource abundance, and energy density. Yet until recently magnesium battery research received little attention, and progress remains slow. The two main hurdles have been the poor performance of positive electrode materials and the dearth of magnesium electrolytes with which to study them.
This is attributable to the much more complicated electrochemistry of magnesium relative to well-established lithium-ion battery studies. Well documented examples include the passivation of magnesium metal[1], corrosion of current collectors[2], and low voltage stability of magnesium electrolytes[3]. Nevertheless, a critical look at the literature reveals that many magnesium studies are conducted using experimental designs that are either dubious or unlikely to yield encouraging results[4].
To address these discrepancies, we show that appropriate electrochemical design choices are crucial to the success of magnesium experiments. This study analyzes how different electrolytes, current collectors, and electrode materials work with (or against) each other. This work is intended to provide a platform for the search for high energy magnesium battery electrode materials.

References

[1] Z. Lu, A. Schechter, M. Moshkovich, D. Aurbach, On the electrochemical behavior of magnesium electrodes in polar aprotic electrolyte solutions, J. Electroanal. Chem. 466 (1999) 203–217. doi:10.1016/S0022-0728(99)00146-1.
[2] D. Lv, T. Xu, P. Saha, M.K. Datta, M.L. Gordin, A. Manivannan, et al., A Scientific Study of Current Collectors for Mg Batteries in Mg(AlCl2EtBu)2/THF Electrolyte, J. Electrochem. Soc. 160 (2012) A351–A355. doi:10.1149/2.085302jes.
[3] J. Muldoon, C.B. Bucur, A.G. Oliver, J. Zajicek, G.D. Allred, W.C. Boggess, Corrosion of magnesium electrolytes: chlorides – the culprit, Energy Environ. Sci. 6 (2013) 482. doi:10.1039/c2ee23686a.
[4] R.C. Massé, E. Uchaker, G. Cao, Beyond Li-ion: electrode materials for sodium- and magnesium-ion batteries, Sci. China Mater. 58 (2015) 715–766. doi:10.1007/s40843-015-0084-8.
Current Redistribution and Uneven Heat Generation in a Lithium-Ion Battery Pack with Cells of Initial Performance Difference
Authors: DAN Dan , Li Zhe , Zhang Yangjun 
Published: February 2020

Lithium-ion battery is one of the most promising candidate for the energy storage system in the automobile industry. In electric vehicles, cells are connected with each other closely due to space constraints, where thermal problem becomes significant during the system operation. Among all parameters, the initial cell inconsistency plays an important role in the changing rules of pack thermal performance. This paper seeks to gain a better understanding of current load and uneven heat redistribution for a lithium-ion battery pack consisted of cells with unequal initial parameter.
This study carries out a multi-physics coupling model for a battery pack consisted of cells with different initial resistance and capacity. A pseudo 2D electro-chemical model coupled with a lumped thermal model is used to describe each cell inside the pack. Based on this cell model, a coupled thermal-electrochemical model for a battery pack is built, which is able to predict the current load distribution and uneven heat generation during the charge and discharge procedure.
Using the coupled electrochemical-thermal model, cell initial parameters’ impact on pack performance was studied, including resistance and capacity inconsistency. Different cell numbers and connection pattern (parallel/series) were also selected to explore the changing mechanisms in load non-uniformity and heat performance.
The Response and Limits of Fast Discharge and Charge Rates of Electrodeposited V2O5 Inverse Opal Networks in Lithium Batteries
Authors: O'Hanlon Sally , O'Dwyer Colm 
Published: February 2020

Structurally stable electrodeposited vanadium pentoxide inverse opal networks on FTO-coated glass are electrochemically tested as a function of C-Rate (discharging and charging) in this study. Recent applications of IOs in electrochemical energy storage have proven that their open-worked structure promotes more stable Li-ion intercalation during cycling(1-3), exhibit improved rate capability due to increased surface area and decreased path lengths for Li+ insertion,(4-7). Rate limitations associated with standard Li-ion batteries can be improved in principle due to shorter diffusion lengths in the 3D architecture(8, 9), particularly important for charging in full cells. V2O5 has been widely investigated(10) as a cathode material for Li-ion batteries due to its high theoretical specific capacity and is useful for reversible Li-ion insertion and removal due to its mixed valance and layered structure.(11) The difference in open-topped versus overfilled (closed top) 3D inverse opal macroporous V2O5 networks, due to electrodeposition growth time, is examined by galvanostatic cycling, and both 3D structure are examined at C-rates in the range 0.5 – 30 C. Electrochemical analysis demonstrates how lithium phase changes increasing C-rate in both open and overfilled network cases, with capacity values investigated after 25 charge/discharge cycles. Raman scattering and X-ray diffraction is used to investigate the change in structure and phase in each case at each C-rate, along with SEM images to visual investigate the effect of C-rate on the V2O5 inverse opal networks.

References

1. E. Armstrong and C. O'Dwyer, J. Mater. Chem. C, 3, 6109 (2015).
2. Y. Zhao, X. Li, J. Liu, C. Wang, Y. Zhao and G. Yue, ACS Appl. Mater. Interfaces (2016).
3. E. Armstrong, D. McNulty, H. Geaney and C. O’Dwyer, ACS Appl. Mater. Interfaces (2015).
4. M. Osiak, H. Geaney, E. Armstrong and C. O'Dwyer, J. Mater. Chem. A, 2, 9433 (2014).
5. F. Zhang, Y. Tang, H. Liu, H. Ji, C. Jiang, J. Zhang, X. Zhang and C.-S. Lee, ACS Appl. Mater. Interfaces (2016).
6. Y. Liang, L. Chen, L. Cai, H. Liu, R. Fu, M. Zhang and D. Wu, Chem. Commun (2016).
7. F. Li, M. Zeng, J. Li, X. Tong and H. Xu, RSC Adv. (2016).
8. D. R. Rolison, J. W. Long, J. C. Lytle, A. E. Fischer, C. P. Rhodes, T. M. McEvoy, M. E. Bourg and A. M. Lubers, Chem. Soc. Rev, 38, 226 (2009).
9. C. O'Dwyer, Adv. Mater.
28, 5681 (2016).
10. D. McNulty, D. N. Buckley and C. O'Dwyer, J. Power Sources, 267, 831 (2014).
11. E. Armstrong, M. O'Sullivan, J. O'Connell, J. D. Holmes and C. O'Dwyer, J. Electrochem. Soc, 162, D605 (2015).
First-Principles Calculation of Li-GIC Compounds: Van-Der Waals Interaction DFT Calculation
Authors: Yamamoto Masahiro 
Published: February 2020

The graphite intercalation compounds(GIC) of lithium is commercially used in lithium ion battery (LIB), then a lot of the experimental and theoretical works on GIC have been reported from the invention of LIB. In our previous study[1] we have shown that first-principles calculation based on the local density approximation(LDA) of Ceperley-Alder(CA) type give us some physic-chemical properties, because the LDA-CA calculation accidentally give us the stable interlayer distance between the graphite layers. The interaction between the layers is believed to be van der Waals (vdW) interaction and this interaction comes from the dynamic properties. In 2004 Dion et al. proposed the approximated method that include the vdW interaction in the density functional framework and some people have shown that the their method works! In this study we have used the vdW-DF2 functional[2] in the VASP code[3] for vdW DFT calculation and compare the results without vdW contribution. The energetics and structure of graphite and LiC6 are in good agreement with the results by Wang et al.[4] The have shown that energetics and structures for Li, K, Na GIC are in good agreement with the experimental results. In our study the energy barriers of the diffusion for lithium ion in LIC6 GIC have been calculated. The energy barrier in the parallel direction of the grapheme plane is 0.3 eV per Li ion without vdW interaction, which is in good agreement with out previous calculation[1]. In the vdW-DF2 calculation the energy barrier is increased up to 0.8 eV, the origin of which may be the attractive character of the vdW interaction between the Li and C. If we expand the C-C interplane distance up to 1 nm which corresponds to the distance between the GIC that contains the solvated intercalants, we have found that the calculated energy barrier in plane direction can be neglected.
The dependence of the interlayer distance and the charged state on the diffusion barrier is now evaluating and will be presented.
References [1] M. Yamamoto and H. Imamura, Tanso, 2004 No.212 81-90. [2] K. Lee et al. Phys. Rev. B, 2010, 82 08101 [3] G. Kresse et al. Phys. Rev. B, 1993, 47, 558-561, J. Comput. Mater. Sci. 1996, 6, 15-50. [4] Z. Wang et al. Rsc. Adv. 2014, 4, 4069-4079.