bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving the Electrochemical Performance of Glucose-Derived Hard-Carbon Na-Ion Battery Anodes By Silicon Oxycarbide Embedment
Authors: Kaspar Jan , Storch Mathias , Graczyk-Zajac Magdalena , Riedel Ralf 
Published: February 2020

Sodium-ion batteries (NIB) hold much promise for energy storage application due to the high abundance and low cost of sodium, combined with the low redox potential of Na/Na+ of -2.71 V vs. SHE, which is only 0.3 V above the one of Li/Li+. However, sodium-ion batteries are less explored and research for promising electrode materials is still a fundamental concern [1].
Within this work, we present a novel approach to increase the electrochemical performance of glucose-derived hard-carbon (HC-G) NIB-anodes by the preparation of silicon oxycarbide-based composites. In particular, the influence of an intrinsically carbon-rich (SiOC/HC-G) and carbon-poor (SiOC(N)/HC-G) ceramic as stabilizing matrix phase is discussed.
Materials were prepared by mixing of glucose with commercially available polysiloxane or polysilazane polymers, followed by thermolysis at 1000 °C. XRD identified the samples of amorphous nature, whereas Raman-Spectroscopy emphasized the disordered character of the generated hard-carbon phase. Compared to pure HC-G, both composites reveal higher insertion/extraction capacities (Figure 1). In addition, SiOC(N)/HC-G shows an excellent cycling stability, while the cycling stability of SiOC/HC-G is less. However, much higher capacities are obtained for the SiOC/HC-G sample. Moreover, SiOC/HC-G demonstrates the best coulombic efficiency of the first cycle of about 83 %, whereas the first cycle efficiency of pure HC-G only amounts 19 %; for SiOC(N)/HC-G 51 % are obtained.
In both cases, the glucose reacts with the polymer precursor upon thermal treatment, yielding a homogeneous composite after pyrolysis. The ceramic matrix acts as laminate towards the interspersed hard carbon and stabilizes the graphene layers against exfoliation during the subsequent insertion and extraction of sodium cations. In the case of SiOC/HC-G, the SiOC phase provides additional free carbon, accounting for the higher capacities. However the laminating effect is less, as compared to SiOC(N)/HC-G, which leads to the weaker cycling stability.
[1] S.-W. Kim, D.-H. Seo, X. Ma, G. Ceder, K. Kang, Adv. Enery. Mater., 2 (2012) 710-721.

Caption to Figure 1: Galvanostatic cycling performance of glucose-derived hard-carbon (HC-G) and SiOC-based/hard-carbon composites SiOC/HC-G and SiOC(N)/HC-G; current rate 37 mA/g.
High-Temperature Cycling Performance of Cathode with DLC Protective Film
Authors: Oka Yoshihiro , Obata Taiki , Takahara Hikari , Nakamura Tatsuya 
Published: February 2020

One of the most important issues is related to the long cycling performance in the secondary batteries, considering their application to hybrid electric vehicle, electric vehicle and stationary storage system. Especially, the improvement of high-temperature cycling performance is the most challenging target. Under such an inhospitable condition, several reasons may be taken for the battery degradation. Among them, the side reaction at the electrode/electrolyte interface is taken place, irrespective to the kind of the electrode material. It can yield high-resistive interfacial layer, giving the kinetic limitation, and dissolution of transition metals, leading to the reductive precipitation on the anode surface. We have tried to suppress the side reaction with help of a diamond-like carbon (DLC) protective film and presented our experimental results.
The sub-nm DLC films were deposited by a hybrid process of plasma-based ion implantation and deposition (PBIID), which enables us to obtain uniform and thin coating at low processing temperature. This process is applicable to the cathode films as well as the electrode particles. In this study, the LiCo1/3Ni1/3Mn1/3O2 cathode film was treated as a typical electrode. An aspect of the DLC protective layer was observed by a cross-sectional TEM. It was found that the sub-nm DLC film was uniformly coated along the form of cathode surface without the damage to the cathode. The electrochemical cycling of the cathode film was evaluated with Li coin cell at the range from 2.5 to 4.5 V under the CC mode at 55°C. The DLC film coating had no influence on the initial charge-discharge properties but a significant positive effect on the cycling stability. For the cathode with DLC protective film, the discharge capacity hardly decreased even after 100th cycles. The cycling stability was also studied with the AC impedance spectra; it was found that the interfacial impedance growth during the cycling was suppressed by the presence of the DLC film. At the conference, the results about the surface analysis of the high-temperature cycled cathode will be presented and discussed.
This work was financially supported by Advanced and Seamless Technology Transfer Program through target-driven R&D, JST.
Improving the Electrochemistry of Anatase for Sodium Ion Batteries By Using Self-Organized TiO2 Nanotubes Prepared By Anodization Under Variable Voltage
Authors: González José Ramón , Alcántara Ricardo , Ortiz Gregorio F. , Nacimiento Francisco , Tirado José L. 
Published: February 2020

The use of TiO2 as negative electrode in non-aqueous sodium ion batteries may show several drawbacks, such as the relatively low gravimetric capacity, low coulombic efficiency at low voltage and poor cyclability. To try to overcome these problems we have followed a new strategy: anatase-type TiO2 nanotubes (nt-TiO2) have been prepared by anodization of titanium under variable voltage. The titanium anodization process under variable voltage modifies de anodization curves (intensity vs. time) in comparison with the anodization under constant voltage at 100 V. As a result of the anodization process, self-organized TiO2 nanotubes with amorphous character are obtained. After annealing at 550°C in air atmosphere anatase-type nt-TiO2 are formed. The relative intensity of the anatase Bragg reflections are influenced by the anodization procedure.The resulting areal capacity values in sodium cells are in the order of 1.0-1.5 mAh/cm2 (as refereed to the fingerprint area of nt-TiO2). When the anodization voltage is linearly increased from 20 to 100 V during one hour, the obtained anatase nt-TiO2 electrode material exhibits improved electrochemical performance. After six hundred discharge-charge cycles the gravimetric capacity vs. Na is about 200 mAh/g. Consequently, the electrochemical behavior in sodium cell of the anatase nt-TiO2 electrode material that we have prepared can be competitive in comparison to lithium.On the other hand, the use of aqueous electrolyte batteries may be an alternative that is explored in this work. Using cyclic voltammetry, we have found that self-organized anatase nt-TiO2 vs. Pt electrode in aqueous NaCl solution exhibits reversible redox processes in the region between ca. -1.0 and -0.2 V. In contrast to the true insertion of lithium ions into the framework of anatase, the reaction with sodium rather takes place in the surface of nt-TiO2.
The Kinetics of Li+ Electrodeposition on Sn Substrate for Li Rechargeable Battery
Authors: Yang Yifu , Xu Qian , Shao Huixia 
Published: February 2020

Sn can form alloy phase with Li with a theoretical specific capacity of 994mAh·g-1, which is more than twice of the graphite. Due to this property, Li-Sn alloy has been considered as one of the most appealing anode materials. In order to make this material to meet the requirements of real application, huge efforts have been devoted to the research of this material [1-3]. In this work, the kinetics of electrodeposition of Li+on Sn substrate is studied, and this can provide theoretical basis on improving the electrochemical properties of Li-Sn alloy anode materials.
Galvanostaticpulse method is used for the study of the kinetics of Li+ electrodeposition on Sn metal and Li-Sn alloy with different Li contents which is formed instantaneously with the deposition of Li. The polarization resistance of Li-Sn alloy electrodes with different Li contents is evaluated by EIS method. Meanwhile, the kinetics of Li+ electrodeposition on Li metal and Cu metal substrates are compared. Some conclusions can be drawn: firstly, Li+ electrodeposition on Sn substrate is a process with continuing change in exchange current density and polarization resistance. Secondly, Li content in Li-Sn alloy has great impact on the kinetics of Li+ electrodeposition, in which the Li-Sn alloy substrate containing highest Li content is the most beneficial one among them. Thirdly, the Li+ deposition performance on Li-Sn alloy substrate containing highest Li content is much better than on Li metal and Cu metal substrates.
References:

[1] M. Winter, J. O. Besenhard. Electrochimica. Acta, 45 (1999) 31-50.
[2] M. Inaba, T. Uno, A. Tasaka. J. Power Sources, 146 (2005) 473–477.
[3] S. C. Chao, Y. C. Yen, Y. F. Song, Y. M. Chen, H. C. Wu, N. L. Wu. Electrochemistry Communications, 12 (2010) 234–237.
Statement:
The novelty of this work is that, it is found that as the deposition of Li+ on Sn surface proceeds, the alloy of Li-Sn is formed with increase of Li content in the alloy. The exchange current density of Li+ deposition on the alloy is changed with the Li content. This feature could affect the overall kinetics Li+ deposition and the cycleability of Li metal anode.
Relating topic: electrode materials (Li battery anodes)
Ionic Liquid Based Synthesis of α-Fe2O3 nanocrystallite and Its Application in Lithium Ion Battery
Authors: Lu Yan , Wen Zhaoyin , Jin Jun , Rui Kun , Hu Yingying 
Published: February 2020

Hematite (α-Fe2O3), which is the most stable iron oxide with n-type semiconducting properties under ambient conditions, is of great scientific and technological importance. Especially in the energy storage field, it has attracted considerable interest because of their low cost and excellent electrochemical properties in rechargeable lithium ion batteries (LIBs).[1,2] Stimulated by both the promising applications of iron oxides and the novel properties of nanoscale materials, considered efforts have been made in the synthesis of α-Fe2O3 nanoparticles, nanorods, nanowires and nanotubes. However, most of the synthesis approaches are complicated and beyond the large scale production. Herein, we report the preparation of α-Fe2O3 nanocrystalline using ionic liquid (BMIBF4) as morphology tuning agent through a facile, one step solvethermal method.
The role of ionic liquid (IL) played in the preparation process was investigated and a possible formation mechanism was proposed. Fig. 1 showed the morphologies of the products with and without ionic liquid in the reaction system. From which, we can see that uniform nanocrystallites were obtained with the addition of ionic liquid, demonstrating it a good morphology controllable agent for the products. Fig.2 showed that ionic liquid did not affect the phase of the products.
A series of experiments about the formation process ofα-Fe2O3 nanocrystallites have been carried out by changing the reaction temperature and time. The results showed that the product obtained at 180 °C for 36 hours exhibited the most homogenous morphology and the best dispersibility. The electrochemical performances of them were examined in rechargeable lithium batteries. Due to the poor conductivity of them, graphene nanosheets (GNSs) were used to composite with them to improve the electrochemical performance. As Fig.3 demonstrated, α-Fe2O3 nanocrystallites were successfully dispersed on the surface of GNS (Fig. 3a,b). It exhibited an initial discharge capacity as high as 1900 mAh g-1, which is much higher than that of primitiveα-Fe2O3 electrode of 1600 mAh g-1in Fig. 3c.
Figure 1. SEM image (a) and TEM image (b) of the product obtained at 180°C for 36 h with IL; SEM image (c) and TEM image (d) of the product obtained at 180°C for 36 h without IL.
Figure 2. XRD patterns of the product obtained at 180°C for 36 h with and without IL.
Figure 3. SEM images (a,b) of GNS supportedα-Fe2O3 nanocrystallites and the first charge-discharge curves of the electrodes at a current density of 50 mA g-1 in LIBs (c).
References
[1] J. Chen, L. Xu, W.Y. Li, X.L. Gou, Advanced Materials, 17 (2005) 582-586.
[2] J.Y. Zhong, C.B. Cao, Y.Y. Liu, W.S. Khan, Chemical Communications, 46 (2010) 3869-3871.
High Quality Graphene for Low Temperatures Lithium-Ion Batteries Application
Authors: Raccichini Rinaldo , Varzi Alberto , Chakravadhanula Venkata S , Kübel Christian , Balducci Andrea , Passerini Stefano 
Published: February 2020

The properties of high quality few-layers graphene, produced though multisteps process involving microwave irradiation of expandable graphite, are presented. Such innovative approach fulfills all desirable requirements (so far missing in the conventional methods, e.g. Hummers method) of being reproducible, low-cost, environmental friendly, with high yield, and scalable.
When used as anode material the so-obtained graphene (hereinafter GRAL), differently from the commonly employed reduced graphene oxide, is able, similarly to graphite, to intercalate/de-intercalate Li ions in the few-layers structure. Its peculiar features such as (i) presence of few defects, (ii) small sheets size, and (iii) nanometric thickness, enable the negative electrode to work at considerably lower temperatures than conventional graphite.
During galvanostatic charge-discharge experiments (specific current of 50 mA g-1), performed in a temperature range comprised between +20°C and -30°C, GRAL exhibits remarkable capacity retention with comparison to commercial graphite. At temperatures above 0°C, GRAL performs quite similarly to graphite. However, at lower temperatures, graphite suffers from dramatic capacity decay resulting on only 9% of capacity retention at -30°C. On the contrary, GRAL is able to retain 65% and 34% of the room temperature capacity when operating at -20°C and -30°C, respectively.
The outstanding performances of this novel few-layers graphene are confirmed also by the very promising low temperature stability, with a coulombic efficiency close to 100%.
Metallization of Silicon Particles for Improved Li-Ion Battery Anodes
Authors: Spreafico Marco , Cojocaru Paula , Biso Maurizio , Apostolo Marco , Magagnin Luca 
Published: February 2020

Silicon is a material that has gained particular interest for the application as anode active material in lithium ion batteries, thanks to its unique reversible lithium insertion capability, which can lead to very high values of specific capacity. However, the main drawback that prevented the spreading of this material in industrial application is its structural instability upon lithium insertion cycling, and different solution have been proposed to address this issue 1
,
2. The very high volume variation that occurs to silicon during cycling leads to difficulty to establish a continuative electrical contact between Si particles and the rest of the electrode. The approach developed in this work is to apply a nanostructured metallic coating to the Si particles, helping to overcome the continuous stresses during cycling and maintaining electrical contact.
In this work, two different metallization techniques have been tested. The presence and composition of the coating on the surface of the particles is confirmed by SEM/EDX and XRD analysis. Anodes containing at least 20%wt Si have been manufactured to perform the electrochemical characterization and to assess the cycling behavior. Coated particles show enhanced structural stability upon cycling, leading to improved cycling efficiency and cycle life. Specific capacity values around 1000 mAh/g are achieved with a 40% increase with respect to pristine Si.
References:
1. C. K. Chan et al., Nature nanotechnology, 3, 31–35 (2008).
2. B. A. Boukamp, Journal of The Electrochemical Society, 128, 725 (1981).
Synthesis and Morphological Influence on High Capacity LiMnBO3 Cathode Material for New Generation Lithium Ion Batteries
Authors: Veena Regupathi , Ganapathi Subramanian Nagarajan , Shanmukaraj Devaraj , Sudarkodi Raman 
Published: February 2020

In search of new cathode material, Borate based electrode, LiMBO3 (M= Fe, Mn and Co) for lithium ion battery offer several attractive features, such as low molar mass, abundant, environmental friendliness and relatively high theoretical capacities (222 mAh/g) [1]. In this view,an effort towards improvement in electronic conductivity of LiMnBO3material via reduction in particle size and appropriate synthesis condition is reported in this paper.
A simplified Sol gel method was adopted for the synthesis of LiMnBO3cathode material. High Purity, analytical grade LiNO3, Mn(NO3)2. 6H2O and H3BO3 were used as precursors. The synthesized powders were annealed at 700oC for 3 hrs under different atmosphere.
Powder X –ray diffraction pattern of the LiMnBO3 revealed the presence of mixed phases of hexagonal and monoclinic in which hexagonal phase is dominant in both Ar and N2atm. [2]. The crystallite size (Debye –Scherrer) calculation indicated nanoparticle formation (~ 38 nm).
The SEM images of LiMnBO3 (Fig.1a) showed elongated spherical shaped particle in Ar atmosphere whereas peculiar tetragonal rod shaped particles was observed for N2atmosphere (fig.1b). The influence of morphological changes on the electrochemical performance is reported in this paper
Cycling profile of LiMnBO3 cells are given in fig.2. The cells were cycled between 1.5 to 4.8V at room temperature at a C rate of C/20. Fig.2, revealed that the capacity was maintained at 198mAh g-1for the first three cycles followed by a good capacity retention upto 35 cycles with a capacity deliverance of 190mAh/g (figure not shown).
From the results, we report a sol gel derived LiMnBO3 that delivers a first discharge capacity of 198mAh g-1 at C/20 rate, the best result reported so far for LiMnBO3to our knowledge.
References:

Shouli Li, et al, “In-situ controllable synthesis and performance investigation of carbon-coatedmonoclinic and hexagonal LiMnBO3 composites as cathode materials inlithium-ion batteries” - Journal of Power Sources, 236 (2013) 54e60

Yong –Suk Leeet al, “Structural and electrochemical behaviour of LiMnBO3 synthesised at various temperature” - Electronic Material Letters (accepted for publication)
A Sodium-Ion Battery Based on Olivine Sodium Iron Phosphate Cathode and Nanostructured Tin Carbon Anode
Authors: Hasa Ivana , Sun Yang-Kook , Hassoun Jusef 
Published: February 2020

Lithium-ion battery is presently the most diffused energy storage system in the electronic portable devices market, this in view of its high energy density and intrinsic safety due the replacement of the reactive lithium-metal by the lithium-insertion, graphite anode. [1,2] The increased demand of lithium and its concentration in few countries contributed to a rapid rise of the price. As consequence, rechargeable electrochemical cells based on sodium, designed for the energy storage, are now attracting large interest due to its abundance and low cost. [3,4]
We report here the behavior of a sodium-ion battery based on a NaFePO4 cathode, obtained by electrochemical Li-Na conversion of LiFePO4 olivine, and a nanocomposite tin-carbon (Sn-C) alloying anode. [5,6] We show that, by adopting a refined, unique electrochemical process, the LiFePO4 can be successfully and efficiently converted in NaFePO4 and demonstrate that this material can be used as cathode in a sodium-ion battery characterized by the reversible electrochemical process NaFePO4 + SnC = Na(1-x)FePO4 + SnxC with good reversibility and rate capability.
[1] M. Armand and J.-M. Tarascon, Nature,7 February 2008, Vol 451;
[2] B. Scrosati and J. Garche, J. Power Sources, 2010, 195, 2419;
[3] M.D. Slater, D. Kim, E. Lee, C.S. Johnson, Adv. Funct. Mater., 2013, 23, 947–958;
[4] B.L. Ellis, L.F. Nazar, Current Opinion in Solid State and Materials Science, 2012, 16, 168–177;
[5]P. Moreau, D. Guyomard, J. Gaubicher, F. Boucher, Chem. Mater., 2010, 22, 4126;
[6]S.-M. Oh, S.-T. Myung, J. Hassoun, B. Scrosati, Y.-K. Sun, Electrochem. Comm., 2012, 22, 149–152;
Perfluorocarbon Additive Behaviour on Lithium Oxygen Battery
Authors: Wijaya Olivia , Rinaldi Ali , Hoster Harry E. , Yazami Rachid 
Published: February 2020

Lithium oxygen batteries have drawn a lot of attention recently due to their potential for high energy density, around three times the amount of the theoretical specific energy of LiCoO2, the commercial lithium ion battery.[1][2] Despite its high theoretical energy density, current lithium oxygen batteries suffer from poor cycle efficiency, poor rate capability, and low cycle life which impede practical application. One of the causes of the drawbacks is the low oxygen solubility and the oxygen transport limitations of the electrolyte. Tackling these challenges is important especially to realize the high rate lithium oxygen battery.
Perfluorocarbons (PFC), the main component of artificial blood, have been investigated as additives for lithium oxygen battery due to their ability to absorb significant volume of oxygen[3]. They are expected to improve the mass transport of oxygen and thus decrease the polarization during discharge. In this work, fluorocarbon compound was incorporated in the ether electrolytes and its performance is tested in lithium oxygen battery. Our results demonstrate that addition of PFC improves the discharge voltage significantly up to 200 mV for 20% PFC addition in 0.1 M LiClO4 in tetraglyme(TEGDME) electrolyte (Figure 1a). We also discover that the effect of PFC additive is more pronounce at thicker electrode, in agreement with the hypothesis that PFC enhances the concentration of oxygen and/or diffusion of oxygen throughout the electrode thickness. However, subsequent investigation on the effect of PFC additive towards the oxygen reduction using Glassy Carbon (GC) Disk electrode in 0.1 M TBAClO4:DME reveals that the PFC additive reacts with the superoxide radical and yields irreversible species during the cyclic voltammetry. This indication is further confirmed by Rotating Ring Disk Electrode (RRDE) on the Au Ring/ GC disk electrode by performing the collection efficiency measurement (Nk). It is found that the collection efficiency increases with increasing rotation speed on the electrolyte with PFC additive, proving that the superoxide species is depleted by chemical reaction with PFC (Figure 1b). Result on the diffusion coefficient of oxygen and superoxide, solubility of oxygen and kinetic of superoxide reaction with PFC will also be discussed to assess the real effect of PFC toward oxygen reduction reaction. In summary, this work has added deeper insight on the consideration of using PFC as electrolyte additive for lithium oxygen battery.
[1] L.-L. Zhang, Z.-L. Wang, D. Xu, X.-B. Zhang, and L.-M. Wang, “The development and challenges of rechargeable non-aqueous lithium–air batteries,” Int. J. Smart Nano Mater., vol. 1, pp. 1–20, Feb. 2012.
[2] A. Kraytsberg and Y. Ein-Eli, “Review on Li–air batteries—Opportunities, limitations and perspective,” J. Power Sources, vol. 196, no. 3, pp. 886–893, Feb. 2011.
[3] R. Battlno, T. R. Rettich, and T. Tominaga, “The Solubility of Oxygen and Ozone in Liquids,” J. Phys. Chem. Ref. Data, vol. 12, no. 2, pp. 163–178, 1983.