batterydata/paper-abstracts huggingface dataset:
In this paper we compare the behavior of LiNi0.5Mn0.5O2, LiNi0.33Mn0.33Co0.33O2 (NMC) and LiNi0.4Mn0.4Co0.2O2 as cathode materials for advanced rechargeable Li-ion batteries. These materials were prepared by a self-combustion reaction (SCR) from the metal nitrates and sucrose, followed by calcination at elevated temperatures. The temperature and duration of calcination enabled the adjustment of the average particle size and size distribution. It was established that the annealing temperature (700–900°C) of the as-prepared oxides influences strongly the crystallite and particle size, the morphology of the material, and the electrochemical performance of electrodes in Li-cells. Capacities up to 190, 180 and 170mAhg−1 could be obtained with Li[NiMn]O2, LiNi0.4Mn0.4Co0.2O2 and LiNi0.33Mn0.33Co0.33O2, respectively. In terms of rate capability, the order of these electrodes is NMC<LiNi0.4Mn0.4Co0.2O2 ≪Li[NiMn]O2. Many hundreds of cycles at full DOD could be obtained with Li[NiMn]O2 and NMC electrodes in Li-cells, at room temperature. All of these materials develop a unique surface chemistry that leads to their passivation and stabilization in standard electrolyte solutions (alkyl carbonates/LiPF6). The surface chemistry was studied by FTIR, XPS and Raman spectroscopy and is discussed herein.
In this work, a new class of single Li-ion conducting polyelectrolytes (SLICPs) were skillfully synthesized from highly delocalized lithium tetrazolate, polyethylene glycols (PEGs) and diisocyanates. The chemical composition of SLICPs was confirmed by FT-IR, NMR and XPS, and the physical and electrochemical properties were investigated with XRD, SEM, DSC, TG, EIS, LSV, etc. The results showed that the related properties could be tailored using various diisocyanates and PEGs, and the SLICPs comprising PEG1000 exhibited higher ionic conductivities and Li+ transference number. It was noted that the conductivity of SLICP prepared from isophorone diisocyanate, lithium tetrazolate and PEG 1000 (IPULi-1000) could be close to 1 × 10−4 S cm−1 at 80 °C without uptake of any organic solvents. Besides, the polymer electrolytes could endure an oxidation potential up to 4.2 V (vs. Li+/Li), and the stable cycle (more than 200 cycles for Li/Li symmetric cell at 30 °C) indicated that the developed SLICPs were compatible with lithium electrode. Hence, the developed SLICPs were promising solid polymer electrolytes materials for Lithium batteries.
Umicore, a market leader in the production of cobalt powder, has announced plans for significant investments at its cobalt refining and recycling plant in Olen, Belgium. The investments, which could total some €25 million, would centre on the upgrade of the cobalt refining and recycling plant. They would also involve the modernization of a number of on-site facilities in order to further improve the EHS performance of the site. Umicore also plans to improve plant efficiency and suggests that by 2020 the site should be able to operate with 70 fewer people than it does today. ‘Such a reduction could be achieved over the coming five years by not replacing retiring employees and therefore without the need for any lay-offs,’ it said in a press release. The upgraded refining facility would enable Umicore to increase its production of cobalt and also increase its ability to recycle cobalt and nickel-bearing residues. According to the company, the upgrade conforms to Umicore's strategy of securing supply for the growth of its Rechargeable Battery Materials business unit as well as for the cobalt and nickel activities in its Cobalt & Specialty Materials segment. ‘We need to do all we can to ensure that Olen remains competitive in a challenging global market and I am convinced that these investments will enable us to achieve this,’ said Jan Vliegen, senior vice president of Cobalt & Specialty Materials and site manager of the Olen plant. Umicore;www.umicore.comThe upgrade conforms to Umicore's strategy of securing supply for the growth of its Rechargeable Battery Materials business unit.
A novel method to produce LiMn2O4/carbon nanocomposites in a rapid, one-step and industrially scalable process is presented. A flame spray and a diffusion flame are combined to continuously produce LiMn2O4 nanoparticles and carbon black, respectively. Powder carbon content is varied by adjusting the diffusion flame conditions. The powders are characterized by X-ray diffraction (XRD), transmission electron microscopy, cyclic voltammetry and galvanostatic cycling for a range of current densities. These LiMn2O4/carbon nanocomposites retain over 80% of their initial galvanostatic discharge capacity for current densities ranging from 5 to 50C-rates, significantly better than pure LiMn2O4 nanoparticles mixed conventionally with commercial carbon blacks. The improved performance of the LiMn2O4/carbon nanocomposites is attributed to the carbon particle contact and/or film coating of the freshly-made LiMn2O4 nanoparticles. This additional well-distributed carbon provides an electrically conductive network that induces a more homogeneous charge transfer throughout the electrode. The suitability of these nanocomposites as a hybrid material is discussed by considering the layout of a thin-layer lithium-ion battery containing these flame-made nanocomposites as positive electrode and LiC6 as negative electrode. The battery’s specific energy is calculated to be 78Whkg−1 (50C-rate) based on the results of lithium-ion insertion capacity experiments and reasonable engineering assumptions on the lithium-ion battery design.
The solid electrolyte interphase on the lithium electrode cycled with an electrolyte solution with polysulfides is investigated by a series of measurement within symmetrical cells. Both discharge–charge curves and EIS (electrochemical impedance spectroscopy) data show that polysulfides in the electrolyte solution play an important role for the stability of the interface on the lithium electrode. These results combined with SEM (scanning electron microscope) images show that the decomposition of the lithium salt (LiTFSI) on the lithium electrode can be prevented by a surface film formed with polysulfides. As shown by XPS (X-ray photoelectron spectroscopy) spectra and depth profiling, the surface film on the lithium anode cycled in the electrolyte solution with polysulfides can be assumed to be composed of two layers. The top layer is composed of the products of the decomposition of LiTFSI and the bottom layer is composed of lithium sulfide produced by the reaction between lithium metal and the polysulfides in the electrolyte solution. We suggest that the bottom layer efficiently prevents the decomposition of the lithium salt on the lithium anode in lithium–sulfur batteries, thereby increasing the stability and cyclability.
In the present study, LiMn2O4 cathode powders were coated with aluminum and gallium using a solution method with two-stage surface modification to obtain a Mn-based powder with an Al–Ga surface modification layer (MAG). It was found that the MAG powders have a higher capacity and excellent cycle characteristics at 55 °C at various current rates, and that the Al–Ga coating layer inhibits the precipitation of Mn ions, which increases the stability of the structure. In addition, although low temperatures generally lead to a reduction of conductivity and capacitance, the Al–Ga coating layer gives the MAG powders low-temperature resistance, with charge–discharge characteristics better at −30 °C. The Al–Ga surface modification coating layer of LiMn2O4 powder is the LiMn2−x−y Al x Ga y O4 phase, which reduces the negative impact of temperature variation. As a result, the MAG powders can be used for high C-rate charging–discharging.
Highly dispersed crystalline/amorphous LiFePO4 (LFP) nanoparticles encapsulated within hollow-structured graphitic carbon were synthesized using an in situ ultracentrifugation process. Ultracentrifugation triggered an in situ sol–gel reaction that led to the formation of core–shell LFP simultaneously hybridized with fractured graphitic carbon. The structure has double cores that contain a crystalline LFP (core 1) covered by an amorphous LFP containing Fe3+ defects (core 2), which are encapsulated by graphitic carbon (shell). These core–shell LFP nanocomposites show improved Li+ diffusivity thanks to the presence of an amorphous LFP phase. This material enables ultrafast discharge rates (60 mA h g−1 at 100C and 36 mA h g−1 at 300C) as well as ultrafast charge rates (60 mA h g−1 at 100C and 36 mA h g−1 at 300C). The synthesized core–shell nanocomposites overcome the inherent one-dimensional diffusion limitation in LFP and yet deliver/store high electrochemical capacity in both ways symmetrically up to 480C. Such a high rate symmetric capacity for both charge and discharge has never been reported so far for LFP cathode materials. This offers new opportunities for designing high-energy and high-power hybrid supercapacitors.
Major incidents are complex, dynamic and bewildering task environments characterised by simultaneous, rapidly changing events, uncertainty and ill-structured problems. Efficient management, communication, decision-making and allocation of scarce medical resources at the chaotic scene of a major incident is challenging and often relies on sparse information and data. Communication and information sharing is primarily voice-to-voice through phone or radio on specified radio frequencies. Visual cues are abundant and difficult to communicate between teams and team members that are not co-located.
An interesting and effective route for improving battery performance using ferroelectric poly(vinylidene difluoride) (PVDF) polymer as a binder material is demonstrated in this work. A ferroelectric PVDF phase developed under the appropriate thermal annealing process enables generation of suitable polarization on active materials during the discharge and charge process, giving rise to longer capacity with lower overpotential at a high current rate. Electrochemical analysis including in situ galvanostatic electrochemical impedance spectroscopy and a galvanostatic intermittent titration measurement revealed that the ferroelectric binder effectively reduced Li-ion diffusion resistance and supported fast migration in the vicinity of active electrodes. Computational results further support that the binding affinity of the ferroelectric PVDF surface is much higher than that of the paraelectric PVDF, confirmed by ideally formed ferroelectric and paraelectric PVDF conformations with Li-ions. Furthermore, we consistently achieved high Li-ion battery (LIB) performance in full cell architecture consisting of a LTO/separator/LFP with a ferroelectric PVDF binder in the anode and cathode materials, revealing that the polarization field is important for fabricating high-performance LIBs, potentially opening a new design concept for binder materials.
Demand response programs are becoming an integral part of the power system, helping create a closer alignment between the electrical service providers and customers. The research described in this paper uses the residential demand response (DR) program during a peak demand event to determine the demand reduction capacity as a virtual storage (VS). As in the marketing business, identifying target customers is vital in the DR program, thus making it more efficient and productive. Additionally, peak load events are very critical in the power system; therefore, it is essential to model an effective demand response program. This paper uses predictive analytics to estimate the level of residential participation in a DR program, and thus the load reduction capacity available, during peak load events. Also derives the mathematical modeling of the demand reduction capacity of a demand response program as a virtual storage system and optimizes it using genetic algorithm technique.
Solid state electrolytic properties of mixtures of Li(BH4)0.75I0.25 and amorphous 0.75Li2S·0.25P2S5 are reported in this study. The enhanced Li-ion conductivities for the Li(BH4)0.75I0.25 phase after addition of 0.75Li2S·0.25P2S5 were found to be within the range for practical solid-state electrochemical storage near room temperature. The highest ionic conductivities are found for the borohydride/sulfide system at 1:2 wt ratio with ∼10−3 S cm-1 at room temperature and an activation energy of 0.30(2) eV. Combined experimental analyses with powder X-ray diffraction and infrared spectroscopy suggest that the synthesized material still include both [PS4 3−] and [BH4 −] entities. Density functional theory (DFT) calculations provide more insights about the origin of the observed ionic behavior according to the induced structural modifications in the BH4–BH4 interactions. Finally, the electrolyte functionality and its compatibility toward an active material are successfully demonstrated by means of cyclic voltammetry (Au vs. Li+/Li) in a large voltage window (up to 5 V) and battery cycling tests with TiS2 electrode, respectively.
Electric vehicles (EVs) have high energy efficiency and low pollutant and greenhouse gas (GHG) emissions compared with conventional internal combustion engine vehicles (ICEVs). This study examines the economic competitiveness of battery electric vehicles (BEVs) in the Chinese market. BEVs are compared with ICEVs using benefit-cost analyses from the perspectives of consumers, society and GHG emissions. A life-cycle cost model is developed to evaluate the lifetime cost of a vehicle. The results show that, with central government subsidies, the BEV life-cycle private cost (LCPC) is about 1.4 times higher than comparable ICEVs. Central government subsidies on BEVs will not be cost effective and efficient unless the annual external cost reduction from using BEV reaches $2500 for a compact vehicle or $3600 for a multi-purpose vehicle. That total cost level would imply a carbon cost of more than $2100 per ton. The current life-cycle external cost reductions from using BEV are around $2000–$2300, which are smaller than government subsidies or LCPC differences between BEV and ICEV. Further projections show that BEVs likely will not be economically competitive in the Chinese market before 2031.
A category of mesoporous carbons-that covers pristine CMK-3, micropore-enriched CMK-3, nitrogen-doped CMK-3 and a combination of nitrogen-doped and micropore- enriched CMK-3 has been prepared via a one-pot wet-impregnation method, using SBA-15 as mesopore template, phenolic resol as carbon precursor, silicate oligomer as micropore template, and nitrogen-rich hexamethoxymethylmelamine as nitrogen precursor. The synthesis is very flexible to control the pore structure and nitrogen doping of the carbons by changing the initial composition of the precursors. The structural similarity of these materials allow them to serve as model systems for mesoporous carbons in general, to comparatively illustrate the enhanced supercapacitor and Li-S cathode properties by nitrogen doping and micropore development. It is found that additional microporosity prevails over the nitrogen doping on the electrostatic adsorption for supercapacitor, while nitrogen doping performs better on the trapping polysulfide species especially at high current rates for Li-S cathode. Simultaneous creation of microporosity and nitrogen doping into mesoporous carbons could combine the synergistic effects, thus greatly improving the electrochemical properties both for supercapacitors and Li-S cathode.
The behaviour of a woven fabric carbon/epoxy composite T-joint (representing a simplified version the T-joint located at the connection between the B-pillar and the longitudinal rocker in a car body structure) is investigated using experimental and numerical methods. Details of the manufacturing process and experimental design factors are considered to understand their influence on the performance of the T-joint structure. The experimental results reveal the influence of manufacturing process and experimental setup on the load-carrying capacity and failure mode of the T-joint. Numerical simulation accurately predicts the stress distribution and load-carrying capacity of the T-joint obtained from experimental tests. The FEM model, which includes the adhesive interface layers at the edges, convincingly represents the experimentally found stiffness: the error is less than 3%. According to Hashin matrix tension criteria, the first ply failure occurs at 3.746 kN when the Hashin failure index (R) becomes equal to 1. Whereas, in the case of experimental tests, the first ply failure occurs around 3.4 kN, at which force the first load drop is observed.
Supercritical carbon dioxide (scCO2) as a treatment medium has a possibility to realize excellent room temperature conductivity more than 10−4 S/cm for polymer electrolytes in the dry state. In this study, a typical high ion-conductive polyether-based electrolyte which consists of poly-[ethylene oxide-co-2-(2-methoxyethoxy)ethyl glycidyl ether] (P(EO/EM)) and lithium perchlorate (LiClO4) was used as a model sample for the scCO2 treatment. We found the suitable scCO2 treatment conditions (pressure, temperature and time) for high conductivity. The conductivity of sample treated at 7.5MPa and 40°C for 40min was more than 100-times higher than that of original without the treatment, and the value decreased only 20% after 30days. DSC measurement revealed that the decrease in glass transition temperature (T g) is caused by the scCO2-treatment. The change of ionic association in the scCO2-treated samples was confirmed using FT-IR measurement. The scCO2 treatment gave rise to increase in peak fraction of free ClO4 − anions (620–625cm−1) and peak shift of ν(C–O–C) mode to lower frequency region (1060–1070cm−1) depending on ether–Li+ interactions.
Ag2Se thin film has successfully been fabricated by pulsed-laser deposition method. X-ray diffraction (XRD) measurement indicated that the as-deposited Ag2Se thin film consisted mainly of orthorhombic β-Ag2Se. A reversible electrochemical reaction of Li/Ag2Se cell has been investigated by discharge–charge and cyclic voltammetry (CV) measurements for the first time. The reversible capacity of Ag2Se electrode exhibited more than 5.6 Li per Ag2Se at 10μA/cm2. Both alloying/de-alloying processes and selenidation/reduction processes of Ag were revealed during the lithium electrochemical reaction of Ag2Se thin film electrode. Ag2Se was found to be one novel candidate of anode materials for rechargeable lithium batteries.
We report a new approach to improve the cyclic stability of lithium nickel manganese oxide (LiNi0.5Mn1.5O4) cathode, in which the cathode/electrolyte interface is modified by using prop-1-ene-1, 3-sultone (PES) as an electrolyte additive. The interfacial properties of LiNi0.5Mn1.5O4 cathode in PES-containing electrolyte have been investigated by scanning electron spectroscopy (SEM), transmission electron microscopy (TEM), thermal gravimetry (TG), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammometry (CV), chronoamperometry (CA), and constant current charge/discharge test. It is found that the application of PES improves significantly the cyclic stability of LiNi0.5Mn1.5O4. After 400 cycles at 1C rate (1C=147mAg−1), the capacity retention of LiNi0.5Mn1.5O4 is 90% for the cell using 1.0 wt% PES, while only 49% for the cell without the additive. The characterizations from SEM, TEM, TG, XRD, and XPS confirm that the LiNi0.5Mn1.5O4/electrolyte interface is modified and a protective solid electrolyte interface film is formed on LiNi0.5Mn1.5O4 particles, which prevents LiNi0.5Mn1.5O4 from destruction and suppresses the electrolyte decomposition.
Soils are recipients of contaminants from the burning of metal-containing materials in bonfires. In order to obtain a better understanding of the impacts of bonfires on soils, a total of 218 surface soil samples were collected from a traditional bonfire site in Galway City, Ireland. Concentrations of 14 elements including Al, Ca, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sc, Ti and Zn in 30 selected samples were determined using ICP-OES. Strong variations were observed for these elements. Concentrations of Zn, Cu and Pb were elevated, indicating that these metals may be influenced by human activities. Therefore, concentrations of these three metals were further measured using a portable X-ray fluorescence (P-XRF) analyser (n =218) and their spatial distribution was investigated using a Geographical Information System (GIS). Soils with elevated metal concentrations, as evident from the spatial distribution maps, coincided with the locations of traditional festival bonfires. The results of this study provide useful information for the management of bonfire sites including the enforcement of a control policy regarding the burning of materials in bonfires.
Electron paramagnetic resonance spectroscopy was used to analyse the changes in local Ni, Mn environment in layered LiNi1/2Mn1/2O2 and spinel LiNi1/2Mn3/2O4 after electrochemical extraction and reinsertion of lithium. For layered LiNi1/2Mn1/2O2, the EPR signal from Mn4+ is only detected, while residual antiferromagnetic correlations between Ni2+ and Mn4+ ions gives rise to strong resonance absorption for LiNi1/2Mn3/2O4 spinel. The first charge process of layered LiNi1/2Mn1/2O2 leads to oxidation of Ni2+ ions located both in the transition metal sites and in the Li sites. The reverse process of reduction of these nickel ions was suggested to proceed between 4.4–3.0V and 2.5–1.4V, respectively. Lithium extraction from LiNi1/2Mn3/2O4 spinel leads to oxidation of paramagnetic Ni2+ to diamagnetic Ni4+ without significant changes in the local environment of Mn4+. For both fully delithiated compositions, Li1−x Ni1/2Mn1/2O2 and Li1−x Ni1/2Mn3/2O4, an EPR spectrum from localized Mn4+ ions is observed, indicating an exhaustion of paramagnetic Ni2+ ions in the vicinity of Mn4+ ions. Furthermore, it has been found that the Mn4+ environment including paramagnetic Mn4+ and Ni2+ neighbours is restored after the first cycle of charge/discharge.
A 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI–BF4) ionic liquid is introduced into an electrolyte as a functional additive to enhance the low-temperature performance of LiNi0.5Co0.2Mn0.3O2 (NCM523)/graphite batteries. Linear sweep voltammetry (LSV), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests show that EMI–BF4 can be oxidized in advance and produce low impedance solid-electrolyte interphase (SEI) films on the electrode surfaces. Compared with the batteries without the EMI–BF4 additive, the capacity retention of the NCM523/graphite batteries with 1% EMI–BF4 additive is enhanced from 82.3% to 93.8% after 150 cycles at a low temperature of −10 °C. In addition, at −30 °C, the discharge capacity of the batteries with 1% EMI–BF4 additive is nearly doubled. And at the room temperature of 25 °C and after 400 cycles, the capacity retention also increases from 80.3% to 85.9%, and the coulomb efficiency remains at approximately 100%. These results demonstrate that EMI–BF4 used as a functional electrolyte additive has promising prospects for application to improve the low-temperature performance of NCM523-based lithium-ion batteries.
Energy storage systems provide several benefits and services in optimizing the power grid's reliability, efficiency and safety. However, the feasibility of energy storage systems varies dependent on the requirements of the applications. Technical limitations in design and type of the storage technology prevents a single storage type to perform equally well in all situations. Hence, it is essential to compare and measure the energy storages’ usefulness and determine their optimal use. To address this issue this study introduces an indexing approach to evaluate the suitability of energy storages for power system applications. Four different energy storages (double-layer capacitor, flywheel, lead–acid battery, lithium-ion battery) are tested for four typical energy storage applications (frequency regulation, voltage support, capacity firming and energy time-shift). The suitability index allows a simple and intuitive way to compare and rank the suitability of energy storages.