bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Electrochemical Characterization of New Electro-Active Polymer Bearing TEMPO Functional Groups
Authors: Sadki Mohand said 
Published: February 2020

Synthesis and electrochemical characterization of new electro-active polymer bearing TEMPO functional groups

L.Assumaa, A.Santiagoa, Y. Kervallaa, JM. Mouescaa, V. Maurela, T. Gutelb, L. Duboisa, S. Sadkia

a. INAC-SPrAM-SYMMES, bLITEN-DEHT-Laboratoire des Composants pour Batteries, CEA 17, rue des Martyrs, Grenoble
Organic radical species, particularly pendant nitroxide radical polymers, have been explored as a cathode-active, charge-storage material for secondary Li-ion batteries1. However, nitroxide radical contained polymers are derivatives of conventional plastics, which are insulator, and a very large amount of conducting agents (such as carbon black, graphite, graphene and carbon fibers), even up to 60-80 wt% of the total electrode, is required in the fabrication of the composite electrode and this leads to a decrease of the composite electrode capacity2. In order to decrease de quantity of conducting agents we combined a stable nitroxide radical with a conductive polymer backbone constituted by 2,7-bisthiophene carbazole, which is characterized by high thermal stability and high conductivity. In this work we present the synthesis of this new electro-active conductive redox polymer, the electrochemical characterization, the ESR characterization and battery test. The previous results showed a very high electrochemical reversibility of this system, and a superposition between the redox potential of bisthiophene carbazole backbone and nitroxide radical . Moreover, the preliminary battery test displayed a good capacity (about 60 mAh / g) and a good life cycle, about 50 cycles for a discharge rate equals to C/10.. Thanks to these preliminary results, this polymer could be a viable alternative to the actual radical redox polymers.
(1) Song, Z.; Hapshen Z., Energy and environmental Science
2013
, 60, 2280.
(2) Lihuan X., Fang, Y., Chang, S., Lvlv Ji, Cheng Z., Electrochimica Acta, 2014,
130,148-155.
Nanowire Devices for Electrochemical Energy Storage
Authors: Mai Liqiang 
Published: February 2020

One-dimensional nanomaterials can offer large surface area, facile strain relaxation upon cycling and efficient electron transport pathway to achieve high electrochemical performance. Hence, nanowires have attracted increasing interest in energy related fields. We designed the single nanowire electrochemical device for in situ probing the direct relationship between electrical transport, structure, and electrochemical properties of the single nanowire electrode to understand intrinsic reason of capacity fading. The results show that during the electrochemical reaction, conductivity of the nanowire electrode decreased, which limits the cycle life of the devices.1 Then, the prelithiation and Langmuir-Blodgett technique have been used to improve cycling properties of nanowire electrode. Recently, we have fabricated hierarchical MnMoO4/CoMoO4 heterostructured nanowires by combining "oriented attachment" and "self-assembly".2 The asymmetric supercapacitors based on the hierarchical heterostructured nanowires show a high specific capacitance and good reversibility with a cycling efficiency of 98% after 1,000 cycles. Furthermore, we fabricated Li-air battery based on hierarchical mesoporous LSCO nanowires and nonaqueous electrolytes, which exhibits ultrahigh capacity over 11000 mAh g-1.3 We also designed the general synthesis of complex nanotubes by gradient electrospinning, including Li3V2(PO4)3, Na0.7Fe0.7Mn0.3O2 and Co3O4 mesoporous nanotubes, which exhibit ultrastable electrochemical performance when used in lithium-ion batteries, sodium-ion batteries and supercapacitors, respectively.4 In addition, we fabricated all-solid-state 3D on-chip micropseudocapacitors with ultrahigh energy and power densities.5 Our work presented here can inspire new thought in constructing novel one-dimensional structures and accelerate the development of energy storage applications.
Reference
[1] L. Q. Mai, Y. J. Dong, L. Xu, C. H. Han. Nano Lett. 2010, 10, 4273;
[2] L. Q. Mai, F. Yang, Y. L. Zhao, X. Xu, L. Xu, Y. Z. Lou. Nature Commun. 2011, 2, 381;
[3] Y. L. Zhao, L. Xu, L. Q. Mai, C. H. Han, Q. Y. An, X. Xu, X. Liu, Q. J. Zhang. PNAS. 2012, 109, 19569;
[4] C. J. Niu, J. S. Meng, X. P. Wang, C. H. Han, M. Y. Yan, K. N. Zhao, X. M. Xu, W. H. Ren, Y. L. Zhao, L. Xu, Q. J. Zhang, D. Y. Zhao, L. Q. Mai. Nature Commun. 2015, 6, 7402;
[5] X. C. Tian, M. Z. Shi, X. Xu, M. Y. Yan, L. Xu, A. Minhas-Khan, C. H. Han, L. He, L. Q. Mai. Adv. Mater. 2015, 27, 7476.
Add Oxygen Additions to Prolong Cyclelife of Hydride Batteries
Authors: Shen Yang , Noréus Dag 
Published: February 2020

At first the title might sound counter intuitive, but metal alloy corrosion during cycling influences the cycle life of NiMH batteries in two detrimental ways. Firstly, it consumes the electrolyte drying out the battery resulting in increasing internal resistivity. Secondly, the corrosion produces hydrogen and when the hydrogen is absorbed in the MH electrode, it shifts the electrode balancing. This rapidly consumes the overcharge reserve in the battery leading to increased internal oxygen pressures in the end of the charging cycle, which in turn makes the battery to vent through the safety valve, accelerating the drying out of electrolyte. This is aggravated by the shift of the Ni-electrode balance to higher pressures in the PCT curve, as this contaminates the oxygen with hydrogen. The recombination of oxygen is significantly slowed down by the presence of gaseous hydrogen.1If oxygen could be added externally, it would react with the hydrogen in the metal hydride forming water. This will counter act the drying out by adding water to the electrolyte and at the same time as it restores the electrochemical electrode balance leading to reduced internal pressures when cycling the battery. This was tested in a bipolar NiMH module comprising 10 cells in series supplied by Nilar AB in Sweden. (cf. figure below) A special feature of the design is that it has a common gas space facilitating external addition of gases. By adding an oxygen aliquot every hundreds of cycles, we could eliminate the pressure build up as the battery aged and significantly reduce the increase in internal resistivity over long time cycling.
1) Z. Ye and D. Noréus, J. Power Sources 208, (2012) 232.

Figure 1
Compatibility Issues Between Electrodes and Electrolytes in Solid-State Batteries
Authors: Tian Yaosen , Shi Tan , Richards William Davidson , Bo Shou-Hang , Kim Jae Chul , Li Juchuan , Ceder Gerbrand 
Published: February 2020

Solid-state batteries have recently attracted significant attention because of their advantages compared with conventional batteries employing liquid electrolytes. Remarkable success has been achieved in the discovery of ceramic alkali superionic conductors as electrolytes in solid-state batteries; however, obtaining a stable interface between these electrolytes and electrodes is difficult. Only limited studies on the compatibility between electrodes and solid electrolytes have been reported, partially because of the need for expensive instrumentation and special cell designs. Without simple yet powerful tools, these compatibility issues cannot be systematically investigated, thus hindering the generalization of design rules for the integration of solid-state battery components.
In this work, we present a methodology that combines density functional theory (DFT) calculations and simple experimental techniques such as X-ray diffraction(XRD), simultaneous differential scanning calorimetry and thermal gravimetric analysis (SDT), and electrochemistry to efficiently screen the compatibility of numerous electrode/electrolyte pairs. Employing a Na solid-state system as an example, we demonstrate the efficiency of our method by finding the most stable system (NaCrO2|Na3PS4|Na-Sn) within a selected chemical space (more than 20 different combinations of electrodes and electrolytes). Important selection criteria for the cathode, electrolyte, and anode in solid-state batteries are also derived from this study.
This work has two important implications for the future studies in the related fields: (1) the study of the stability window of the electrolyte and the reaction conditions and products of the reactions between electrode and electrolyte provide an essential guide for integrating all-solid-state battery components; and (2) this current method can significantly accelerate the expansion of the electrolyte/electrode compatibility database.

Figure 1
Multi-Scale Modeling and Experimental Characterization of Charge Process of Li-O2 Batteries: Impacts of Particle Size and Cycling History
Authors: Yin Yinghui , Gaya Caroline , Torayev Amangeldi , Thangavel Vigneshwaran , Larcher Dominique , Franco Alejandro A. 
Published: February 2020

Li−O2 batteries have attracted significant attention due to their high theoretical capacity up to ~3000 Wh/kg, but they are still facing many challenges which avoid their penetration in practical applications. Their high charging voltage, which usually reaches 3.8 V and even more than 4 V, leads to problems such as poor round-trip efficiency, unfavorable parasitic reactions and a large potential gap between charge and discharge, resulting in an intrinsic loss of energy efficiency from source to end. The major part of this potential gap is due to large charge overpotential. Therefore, it is important to develop better understanding of the charge process.
In this work, a comprehensive multiscale model is reported to describe charge processes of Li−O2 batteries. On the basis of a continuum approach, the present model combines mathematical descriptions of mass transport of soluble species (O2, Li+, LiO2) and detailed elementary reactions. The decomposition kinetics of the Li2O2 particles are assumed to be morphology dependent and the simulated charge curves are in good agreement with experimental studies reported in literature previously.1 The model along with the assumed reaction mechanisms provides physical explanations for the characteristic two-step charge profiles. Moreover, since the morphology of Li2O2depends strongly on the applied current density during discharge and operation history upon cycling, the model underlines the strong link between discharge and charge processes. The experimental validation and comparison will be also discussed in the talk.
[1] Zhai, D.; Wang, H.-H.; Yang, J.; Lau, K. C.; Li, K.; Amine, K.; Curtiss, L. A. J. Am. Chem. Soc.
2013, 135, 15364–15372.
[2] Y. Yin, C. Gaya, A.Torayev ,V. Thangavel, A. A. Franco. J. Phys. Chem. Lett., 2016, 7 (19), 3897–3902

Figure 1
Plastic Deformation of Lithium Metal and Impact on Dendrite Growth Process
Authors: Barai Pallab , Higa Kenneth , Srinivasan Venkat 
Published: February 2020

Lithium metal has attracted interest as an alternative anode material for lithium ion batteries due to its extremely low reduction potential (-3.04V with respect to standard hydrogen electrode) and very high theoretical specific capacity (3860mAh/g of Li). However, lithium dendrite growth is a major challenge preventing the widespread commercial use of lithium thin films as lithium ion battery anodes.
It has been observed experimentally that stiff protective layers are capable of preventing the growth of dendritic protrusions. In a previous article[1], the present authors investigated a dendritic protrusion into a solid polymer electrolyte/separator region. Under the assumption of elastic deformation, stress fields and their impact on the current distribution were calculated. It was found that operation at low current density did not lead to any dendrite growth. Also the stress field under the assumption of linear elastic deformation significantly exceeded the yield strength of both lithium metal and polymer electrolyte region.
Contrary to the results of this previous analysis, there are several reports of lithium dendrite growth in systems where PEO-based polymers have been used as the electrolyte[2]. Elucidation of the dendrite growth mechanism within these Li/PEO systems is the main aim of the present work, which extends the earlier model by considering i) a more realistic elastic-plastic description of lithium metal and PEO electrolyte deformation, and ii) operation at current densities close to the limiting current, at which significant concentration and potential gradients evolve according to concentrated solution theory, promoting dendrite growth through higher total current density at dendrite protrusion peaks than valleys. An electrolyte phase with a higher elastic modulus can suppress this growth by i) reducing reaction current density at the peak through increased compressive stress, and ii) reducing variations in ionic conduction path lengths by decreasing dendritic protrusion height. Based on these two mechanisms, the minimum value of the elastic modulus needed for the electrolyte phase to prevent growth of dendritic protrusions is estimated.
References:
1. Barai, P., K. Higa, and V. Srinivasan, Effect of initial state of lithium on the propensity for dendrite formation: A theoretical study. Journal of the Electrochemical Society, 2016. Accepted, In press.
2. Brissot, C., et al., Dendritic growth mechanisms in lithium/polymer cells. Journal of Power Sources, 1999. 81: p. 925-929.

Figure 1
Long Cycle Life LiFePO4 / AC Hybrid Cathodes for Lithium Ion Capacitors
Authors: Shellikeri Annadanesh , Zheng Jun-Sheng , Yturriaga Steven , Cao Wanjun , Zheng Jim P. 
Published: February 2020

Energy storage devices which can bridge the gap between the energy density of Lithium ion battery and the power density of electric double layer capacitor have been gaining interest. Lithium ion capacitor (LIC), with its unique charge storage mechanism with hybrid/composite electrodes is one such device which has attracted much research recently 1, 2. We report here a Hybrid LIC consisting of a Lithium Iron Phosphate (LFP) / Activated Carbon (AC) composite cathode in a synergetic ratio combination, while elaborating on the charge sharing and transition between the faradaic and non-faradaic reactions in the hybrid device. The results from this investigation of energy and power performance, cycle life and anode effects will be presented. The preliminary results, Figure 1, show that during the cycle life study carried out at a very high C- rate of 60C, the LIC device displays a very high capacity retention with no evident capacity decay (retention of 99.99%) over 15000 cycles (ongoing), while delivering an energy density of 70 Wh/Kg act. wt.+ Li-Loading at 1C rate.

Wang B, Wang QM, Xu BH, Liu TF, Wang DL, Zhao G. The synergy effect on Li storage of LiFePO4 with activated carbon modifications. RSC Adv. 3, 20024–20033 (2013).

Shellikeri, A., Hung, I., Gan, Z., Zheng J.P. In situ NMR Tracks Real-Time Li Ion Movement in Hybrid Supercapacitor - Battery Device, J. Phys. Chem. C, 120, 6314-6323 (2016).

Figure 1
(Invited) Tire-Derived Carbon Anodes for Lithium-Ion and Sodium-Ion Batteries
Authors: Paranthaman Mariappan Parans 
Published: February 2020

Carbon powders recovered from waste tires are considered as one of the most promising anodes for both lithium-ion and sodium-ion batteries. The tire-derived carbons obtained by pyrolyzing the acid-treated tire at 1100 °C. The carbon interlayer distances for crystalline carbon areas were determined to be 4.7 Å. These values are ideal for lithium and sodium intercalation. When the pyrolysis temperature is increased from 1100 to 1600°C, the capacity of the plateau below 0.2 V increases dramatically and this could help increase the full cell energy density. The 1600°C treated carbon shows a capacity of 203 mAh g-1after 100 cycles with sodium-ion batteries. We will report the current status of the tire-derived carbon powder scale up efforts and its use in energy storage applications.

Acknowledgements

This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division.
Influence of Electrolyte Penetration Depth and How It Affects the Electrochemical Performance of Cathodes in Zn-Air Batteries
Authors: Kube Alexander , Wagner Norbert , Friedrich K. Andreas 
Published: February 2020

One of the major drawbacks of renewable energy production is that efficient energy storage is required, due to the intermittent nature of wind and solar power. The EU funded Project “ZAS – Zinc Air Secondary batteries based on innovative nanotechnology for efficient energy storage” has the goal to overcome this drawback by developing a new generation of secondary zinc-air batteries.
Zinc based metal-air batteries have the advantage of high energy density, because oxygen from ambient air is used without in-cell storage. As a consequence, lighter batteries are produced with the reversible available Zinc as the only limiting factor.
However, before Zn-air batteries can be used as secondary elements some obstacles have to be overcome. The low cyclability of state of the art Zn-air batteries is caused by the passivation rate and dendrite growth of zinc, carbonate formation in the alkaline electrolytes, corrosion of cathode materials and flooding of the cathode.
Due to the volume expansion of Zinc in alkaline Zn-air batteries, it is important to optimize the penetration depth of electrolyte into the porous structure of the cathode by an appropriate pore size distribution.
Electrochemical impedance spectroscopy measurements were conducted for different applied electrolyte pressures and correlated to the electrolyte penetration depth and the electrochemical performance.
To get a better understanding how the electrolyte infiltrates the porous structure, an electrolyte intrusion cell was build. The volume increase and decrease of the zinc during charge and discharge could be mimicked with the developed cell by electrolyte intrusion and extrusion. The effect of the pore size distribution is strongly reflected in this measurements. This test was done for electrodes at different stages of degradation, to see how the penetration characteristics change over the cycle life of the cathode and how a long life battery could be obtained. Additionally electrodes at different state of charge (SOC) were compared and, in addition, changes in hydrophilic and hydrophobic pore properties were studied.
TiO2 Supported By Acid Treated Graphene Oxide As an Oxygen Reduction Catalysts
Authors: Grewal Simranjit , Macedo Andrade Angela , Karimaghaloo Alireza , Lee Min Hwan 
Published: February 2020

Renewable energy devices such as fuel cells and metal air batteries involves oxygen reduction reactions (ORR), often the performance-determining process of the device. While Pt and its alloys have been the materials of choice due to their high catalytic activity, intense efforts have been made to find alternatives due to their prohibit cost, limited availability and instability. In this presentation, we report a study of TiO2–graphene hybrid as a cost effective option and more environmentally friendly alternative ORR catalyst. While TiO2 has been rarely considered to be an effective ORR electrocatalyst, a recent study by Pei and colleagues reported that oxygen-deficient titanium dioxide rendered surprisingly competitive ORR activity and excellent durability.[1] Motivated by this work and additional advantages of TiO2-x such as abundance, safety and cost effectiveness, we probed the feasibility of applying self-doped TiO2-x based on graphene oxide (GO) to ORR catalyst. This hybrid structure leverages the extremely high surface area and excellent electronic conductivity of reduced GO, which is highly advantageous for maximizing catalytically active sites per mass.[2] Since only the wrinkles and edges of GO are populated with active sites (binding functional groups), GO was treated with acid (HBr acid and/or oxalic acid) to functionalize the non-active sites (epoxide groups) on its basal plane. HBr acid is expected to create hydroxyl groups, and additional oxalic acid treatment is used to create carboxyl groups. These functional groups are then used to bind TiO2nanoparticles. [3]
TiO2/GO hybrid materials was synthesized by a hydrothermal reaction using three different kinds of GO: as-synthesized, HBr-treated, and HBr + oxalic acid-treated GOs. For simplicity, we named the resulting hybrid materials as GT (i.e. GO-TiO2), HGT (HBr-treated GO-TiO2), and HOGT (HBr and oxalic acid-treated GO-TiO2), respectively. From a series of characterization, we found that HOGT samples show the best catalytic activity among the samples with a four electron process, whereas the other samples show a two-electron processes. It was also observed that HOGT showed the best performance when reacted at the highest temperature (160°C) unlike the other samples. From these observations, it is concluded that high density of carboxyl group is essential in rendering high performance and durability toward ORR catlysis.
This project is funded by NASA Advanced STEM Training and Research (ASTAR) Fellowship (NNX15AW57H) and NASA MUREP Institutional Research Opportunity (MIRO) Program (Grant No. NNX15AQ01A).

References

[1] Pei, D.-N. et al.
Nat. Commun. 6, 8696 (2015).

[2] Sun, Y. et al. Graphene based new energy materials. Energy Environ. Sci. 4, 1113 (2011).

[3] Chen, M. et al. Sci. Rep. 5, 10389 (2015)

Figure 1
Exploring the Capacitive Performance of the Transition Metal Carbonitride Mxene Ti3CNTx
Authors: Mathis Tyler , Alhabeb Mohamed , Gogotsi Yury 
Published: February 2020

Transition metal carbides, nitrides, and carbonitrides known as MXenes are a growing family (20+ members) of two dimensional (2D) materials that have garnered much attention for the unique physical, electrical, and optical properties of this new class of materials[1]. Titanium Carbide (Ti3C2Tx) MXene based electrodes have shown great potential for energy storage applications due to their attractive properties such as their high specific capacitances due to redox active transition metals at their surfaces[2, 3] and the high conductivities of MXenes (5000 S/cm) when they are fabricated into free-standing, flexible films[4]. To date, relatively few MXenes have been used as electrode materials for electrochemical capacitors, all of which have been carbides.
Here we examine for the first time the electrochemical performance of a carbonitride MXene, Ti3CNTx, as a supercapacitor electrode material. The structure of Ti3CNTx is similar to Ti3C2Tx, with nitrogen and carbon layers sandwiched between three layers of titanium instead of only two layers of carbon. The Ti3CNTx investigated shows high specific capacitances in acidic electrolytes and good rate performance, similar to previous reports on Ti3C2Tx-MXenes, but the charge-discharge response of Ti3CNTx-MXene during cyclic voltammetry is completely different from carbide based MXenes. These results show how manipulation of the composition of MXenes can influence their energy storage properties.
1. Naguib, M. and Y. Gogotsi, Synthesis of two-dimensional materials by selective extraction. Acc Chem Res, 2015. 48(1): p. 128-35.
2. Lukatskaya, M.R., et al., Cation intercalation and high volumetric capacitance of two-dimensional titanium carbide. Science, 2013. 341(6153): p. 1502-5.
3. Ghidiu, M., et al., Conductive two-dimensional titanium carbide 'clay' with high volumetric capacitance. Nature, 2014. 516(7529): p. 78-81.
4. Shahzad, F., et al., Electromagnetic interference shielding with 2D transition metal carbides (MXenes). Science, 2016. 353(6304): p. 1137-1140.