batterydata/paper-abstracts huggingface dataset:
The aim of this study was to assess time of day and sleep deprivation impacts on motorcycling performance taking into consideration key variables, such as reaction time, motor coordination and vigilance that are principally involved in a riding task. Eight subjects participated in different tests sessions planned at 06:00 and 18:00h after a normal night's sleep and after a night of total sleep deprivation. During each session all subjects completed “laboratory” and “motorcycling” tests that were designed to assess each of the variables tested. As classically observed in sport performance, motorcycling performance demonstrates a time of day fluctuation by increasing from 06:00 to 18:00h during the day after a normal night's sleep. For each variable tested, the effects of sleep deprivation depend on the design of the test conditions. Thus, the data collected in laboratory specific conditions are more affected than those noted in arranged motorcycling situations. Taking into account that the sample size used in this study was limited, which may limit the results interpretations, these discrepancies suggest that during complex tasks, compensation mechanisms may be set up between different resources so as to maintain a good level of performance.
The growing demand for electrical energy is one of the most important subjects today. Decreasing amount and environmental effect of fossil fuels does not seem to surmount this challenge. Renewable energies give a good perspective to be an alternative to fossil and nuclear-fueled power plants, in order to meet growing demand for electrical energy. Hydropower is well known in this category. Hydrokinetic energy technologies are relatively new than other hydropower systems. In this work has been investigated these kinds of hydrokinetic energy, and given some detailed information about current base of hydrokinetic. It has tried to give some knowledge in order to familiarize with the hydrokinetic turbine and generator. The selection information of a suitable turbine has been mentioned.
Fully lithiated lithium sulfide (Li2S) has become a promising cathode material for Li/S cells due to its high theoretic capacity (1166mAhg−1) and specific energy (2600Whkg−1). However, low utilization of sulfur and poor rate capability still hinder the practical application of Li/S cells. In this paper, a carbon coated Li2S/graphene composite (Li2S/G@C) was developed by incorporating Li2S nano spheres with single-layered graphene and further forming a durable protective carbon layer on the surface of the Li2S particles using a facile CVD method. The high rate capability and remarkable cycle life of the Li2S/G@C cathode were demonstrated, which was mainly attributed to the unique structure of the Li2S/G@C that can significantly improve not only the electrical conductivity, but also the mechanical stability of the sulfur cathode.
This paper reports sol–gel derived nanostructured LiFePO4/carbon nanocomposite film cathodes exhibiting enhanced electrochemical properties and cyclic stabilities. LiFePO4/carbon films were obtained by spreading sol on Pt coated Si wafer followed by ambient drying overnight and annealing/pyrolysis at elevated temperature in nitrogen. Uniform and crack-free LiFePO4/carbon nanocomposite films were readily obtained and showed olivine phase as determined by means of X-Ray Diffractometry. The electrochemical characterization revealed that, at a current density of 200mA/g (1.2C), the nanocomposite film cathodes demonstrated an initial lithium-ion intercalation capacity of 312mAh/g, and 218mAh/g after 20 cycles, exceeding the theoretical storage capacity of conventional LiFePO4 electrode. Such enhanced Li-ion intercalation performance could be attributed to the nanocomposite structure with fine crystallite size below 20nm as well as the poor crystallinity which provides a partially open structure allowing easy mass transport and volume change associated with Li-ion intercalation. Moreover the surface defect introduced by carbon nanocoating could also effectively facilitate the charge transfer and phase transitions.
The metal complex formation and the electrical properties of amorphous solid polymer electrolytes, based on poly(butadiene–acrylonitrile) copolymer (PBAN) and CoCl2, have been studied over the homogeneity region of the system limited by the CoCl2 concentration of 1.89molkg−1. It has been found that ionic conductivity is carried out by the unipolar anion transfer at lower CoCl2 concentrations (up to 0.10molkg−1). As the CoCl2 concentration increases, electronic conductivity appears in addition to ionic conductivity, and the former becomes dominant, starting from 0.38molkg−1. It has been shown that the nature of charge carriers is determined by the composition of metal complexes formed by CoCl2 and the macromolecular solvent PBAN. At lower concentrations, the [Co2L2Cl4]0 dimers are the predominant species (L being macromolecule side groups CN), and their dissociation is followed by the formation of mobile Cl− anions and immobile binuclear [Co2Cl3]+ complexes. As CoCl2 concentration increases, polynuclear [Co n L2Cl2n ]0 (n >2) complexes appear (L being CN and CC groups of PBAN). Specific features of chemical bonds in π-complexes of transition metals result in the appearance of electronic charge carriers. The abrupt increase in conductivity observed at the highest CoCl2 concentration is connected with the formation of a percolation network of polynuclear [Co n L2Cl2n ]0 complexes.
In valuing new active materials chemistries for advanced batteries, the theoretical specific energy is commonly used to motivate research and development. A packaging factor is then used to relate the theoretical specific energy to the pack-level specific energy. As this factor is typically assumed constant, higher theoretical specific energies are judged to result in higher pack-level specific energies. To test this implicit assumption, we calculated the fraction of the theoretical specific energy achieved on the pack level for hypothetical cell chemistries with various open-circuit voltages and theoretical specific energies using a peer-review bottom-up battery design model. The pack-level specific energy shows significant dependence on the open-circuit voltage and electrochemical impedance due to changes in the quantity of inactive materials required. At low-valued average open-circuit voltages, systems with dramatically different theoretical specific energies may result in battery packs similar in mass and volume. The fraction of the theoretical specific energy achieved on the pack level is higher for the lower theoretical specific energy systems mainly because the active materials mass dominates the pack mass. Finally, low-valued area-specific impedance is shown to be critical for chemistries of high theoretical specific energy and low open-circuit voltage to achieve higher pack-level specific energies.
Structure-resolving simulation of porous materials in electrochemical cells such as fuel cells and lithium ion batteries allows for correlating electrical performance with material morphology. In lithium ion batteries characteristic length scales of active material particles and additives range several orders of magnitude. Hence, providing a computational mesh resolving all length scales is not reasonably feasible and requires alternative approaches. In the work presented here a virtual process to simulate lithium ion batteries by bridging the scales is introduced. Representative lithium ion battery electrode coatings comprised of μm-scale graphite particles as active material and a nm-scale carbon/polymeric binder mixture as an additive are imaged with synchrotron radiation computed tomography (SR-CT) and sequential focused ion beam/scanning electron microscopy (FIB/SEM), respectively. Applying novel image processing methodologies for the FIB/SEM images, data sets are binarized to provide a computational grid for calculating the effective mass transport properties of the electrolyte phase in the nanoporous additive. Afterwards, the homogenized additive is virtually added to the micropores of the binarized SR-CT data set representing the active particle structure, and the resulting electrode structure is assembled to a virtual half-cell for electrochemical microheterogeneous simulation. Preliminary battery performance simulations indicate non-negligible impact of the consideration of the additive.
Union Process, a manufacturer of particle size reduction and dispersing equipment, has manufactured a grinding mill for battery technology. The Attritor mill has a special high purity zirconium oxide (yttria-tetragonal zirconia polycrystal-stabilized) grinding tank that is jacketed for cooling. The mill is driven by a 7.5 HP motor that is totally enclosed, fan-cooled, and explosion-proof. A variable frequency (inverter) drive is utilized and is installed in a National Electrical Manufacturers Association enclosure. The mill also includes a special ZrO2 discharge bar grid for use with the 5 mm yttria zirconium oxide media being used for the application. Union Process;www.unionprocess.com
In the present study, multi-spectroscopic methods were applied to investigate the effect of NiO nanoparticles on the structure, activity, and stability of proteinase K. To this aim, UV–Vis spectroscopy, circular dichroism photometry, and spectrofluorometry were conducted. UV absorption spectroscopy results revealed that with the addition of NiO nanoparticles, the maximum absorption of the enzyme showed hyperchromism. The regular decrement in the intrinsic fluorescence intensity of the enzyme was obtained with the increase in NiO nanoparticles concentrations. Far-circular dichroism also demonstrated a reduction in the β-sheet and β-turn and an increase in the α-helix content. Furthermore, the results obtained from this investigation revealed that the catalytic activity and thermal unfolding of the enzyme were improved in the presence of NiO nanoparticles in a concentration-dependent manner. Thus, NiO nanoparticles acted as an activator and stabilizer of proteinase K. Finally, the thermodynamic parameters showed that the enzyme–NiO nanoparticles combination was spontaneous and that the hydrophobic interactions and electrostatic forces played a key role in the interaction of the nanoparticles with the enzyme.
Electrochemical energy storage (EES) devices combining high energy density with high power density are necessary for addressing the growing energy demand and environmental crisis. Nickel oxide (NiO) is a promising electrode material for EES owing to the ultrahigh theoretical specific capacity, but the practical values are far below the theoretical limit to date, with inferior rate and cycling performances. Herein, we report the novel mesostructured NiO/Ni composites, which consist of hetero-NiO/Ni components at nanoscale while displaying 3D porous architectures at mesoscale, with adjustable metallic Ni content in a wide range. The unique mesostructure boosts the EES performance of NiO to its theoretical limit with the ultrahigh specific capacity, high rate capability and stability. The superior performance is well correlated with the synergism of the high accessibility to electrolyte, short solid-state ion diffusion length, and much enhanced conductivity of the mesostructured NiO/Ni composites. This study demonstrates a new strategy likely applicable to other transition metal oxides in maximizing their potential in energy storage, i.e. by constructing the similar mesostructured metal-oxide/metal composites.
In today’s modeling and analysis of electrochemical cycling of Li- and Na-ion batteries, an assumption is often made regarding the interphase that forms between the active material and liquid electrolyte at low potentials, the so-called solid-electrolyte interphase (SEI). The SEI is generally assumed to act like an Ohmic resistor despite its complex chemical composition and porosity distribution. Here, one reports that this assumption does not hold for alkali-ion batteries. The SEI possesses a non-linear overpotential characteristic which saturates already at low current density of 0.1mAcm−2 giving only 3.3±1mV for Li-metal electrodes in different electrolytes. For Na- and K-metal electrodes, these SEI overpotentials become dominating with 31mV and 72mV at the same low current densities giving significant disadvantages over Li-ion batteries for commercial applications. With the introduction of a new term, one achieves agreement between the parameters from galvanostatic cycling and electrochemical impedance spectroscopy for the first time. The discovery of the non-linear SEI overpotential disrupts the general believes about the role of the SEI for today’s batteries as it is basically negligible for Li-ion batteries at room temperature.
A new experimental set-up constituted of an electrochemical cell connected to a compression load cell and acoustic emission (AE) equipment was used for monitoring the force and the cracking of metal hydride electrodes generated by their volume expansion/contraction during their cycling. Two materials were studied: a commercial LaNi5-based alloy and an amorphous MgNi alloy prepared by ball milling. During the charge of the LaNi5-based electrode, a concordance was observed between the increase of the force generated by its volume expansion and the increase of the AE activity associated with the particle cracking. This correlation was not observed during the charge of the MgNi electrode, which tends to confirm that the main origin of the cracking of the MgNi particles is not their volume expansion but is rather due to the mechanical action of the H2 bubbles produced at the end of the charge step. In addition, on the basis of the generated/relaxed force rates, the volume expansion/contraction of the electrode appeared more progressive with the MgNi alloy than with the LaNi5-based alloy. This could result from the lack of abrupt α–β phase transition region in the MgNi alloy due to its amorphous structure.
The design of micro/nanostructures with high porosity is very important to achieve reliable and high-performance capacitive materials for electrochemical energy storage. The complexity of this strategy is limited by the lack of a facile method to synthesize multi-hierarchical architectures with both high electroactive surface area and fast ion diffusion ability. Here, we report a designed MnCo2O4/Ni electrode with multilevel hierarchy containing mesoporous MnCo2O4 nanosheet layers and vertically aligned MnCo2O4 nanoflake layers on a macroporous Ni foam support (∼500 μm). The dual-MnCo2O4 layers are well connected with each other and grown directly on the Ni foam support. As a result, the obtained dual-MnCo2O4/Ni electrode delivers an excellent specific capacity up to 283 mAh g−1 and long-term performance stability over 2000 cycles.
The combination of zirconium doping and surface conductive polypyrrole coating is successfully demonstrated to enhance the high voltage electrochemical performances of LiNi0.5Co0.2Mn0.3O2 (NCM) cathode materials. The lattice parameters calculated from the X-ray diffraction (XRD) patterns by Rietveld refinement reveal that the cation mixing degree is restrained and the lithium slabs spacing is broadened after zirconium substitution (NCMZ). A compact and continuous polypyrrole thin film is satisfactorily coated onto the surface of zirconium-doped (NCMZ/PPy) sample, which is confirmed by fourier transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM) and transmission electron microscope (TEM). Though the initial discharge capacity of NCMZ/PPy sample is slightly lower than pristine one, the cycling stability is dramatically improved. Notably, NCMZ/PPy sample shows capacity retention of 89.83% at 1C after 100 repeated cycles, while that of pristine one remains only 69.36%. When the electrodes cycled at 2C for 200 cycles, the capacity retention of NCMZ/PPy still reaches up to 78.83%, and that of pristine one is only 56.79%. The presence of polypyrrole network acts as a capsule shell, which can protect the active substance from erosion caused by the HF attacking. As a result, the cycling stability and rate performance of co-modified sample are both better than those of bare LiNi0.5Co0.2Mn0.3O2 sample and zirconium doped materials.
For a period of time, the O2 cathode has been the focus of research, while the study of lithium anodes and their interactions is quite rare in rechargeable lithium–oxygen (Li–O2) batteries. Actually, the unstable interface between a Li metal anode and the electrolyte in the presence of O2 will eventually lead to battery failure. It was proposed that lithium nitrate (LiNO3), a well-known stabilizing additive being able to form a passivation solid–electrolyte interphase (SEI) on the Li metal surface, could be introduced into the electrolyte of Li–O2 batteries to improve their performance. Nevertheless, the effective utilization of LiNO3 in this system has heretofore been limited due to the dissolution of NO2− species, one of the components of the SEI, as well as O2 corrosion issues on the Li metal side, thus resulting in unstable cycling of Li–O2 batteries. Herein, by combining the electrochemical polishing technology with the LiNO3 reduction chemistry, we construct on a Li metal surface a stable molecularly smooth SEI which possesses a unique multi-layered structure that encapsulates the soluble NO2− species inside the inner layer. Such an SEI film can not only avoid the negative effects caused by the dissolution of NO2−, but also effectively suppress the dendrite growth on and the O2 permeation to the Li surface. Consequently, the cycle lives of O2-saturated symmetric Li cells and Li–O2 batteries are both improved substantially. Our work offers an effective strategy to protect Li metal anodes in Li–O2 batteries, and meantime, provides a novel insight into the rational utilization of electrolyte additives.
Endoscopic capsule is a well-known concept that provides minimal invasive assessment of digestive tract. We describe the work progresses of a capsule - Cap4U – with the size and shape of a common pill and containing a minute camera. The Cap4U is within the novel embedding Wireless Power Transfer System (WPTS). This technology allows the transmission of electrical energy from an external power source, such as the electrical power grid or a consuming device, without the use of electrical conductor wires. Several techniques architecture used to implements the present novel endoscopy system are explained. The specific requirements of image acquisition in one hand and the limitations in the size of the Cap4U in the otherhand, as well as, the energy restriction and the electromagnetic interferences were considered in the present work in all the technical options carried out.
A two-stage hierarchical Microgrid energy management method in an office building is proposed, which considers uncertainties from renewable generation, electric load demand, outdoor temperature and solar radiation. In stage 1, a day-ahead optimal economic dispatch method is proposed to minimize the daily Microgrid operating cost, with the virtual energy storage system being dispatched as a flexible resource. In stage 2, a two-layer intra-hour adjustment methodology is proposed to smooth the power exchanges at the point of common coupling by coordinating the virtual energy storage system and the electric vehicles at two different time scales. A Vehicle-to-Building control strategy was developed to dispatch the electric vehicles as a flexible resource. Numerical studies demonstrated that the proposed method is able to reduce the daily operating cost at the day-ahead dispatch stage and smooth the fluctuations of the electric power exchanges at the intra-hour adjustment stage.
The electrochemical behavior of the aluminum current collector with a fresh surface (the scratched aluminum foil) in three kinds of Grignard reagents/THF electrolytic solutions has been studied by cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS) analysis methods. The experimental results show that the passivating film on aluminum foils after five cycles of CV tests is mainly composed of Al2O3. The pitting potentials of scratched aluminum foils in three kinds of Grignard reagents/THF electrolytic solutions increase in the order of EtMgCl/THF<EtMgBr/THF<PhMgCl/THF, which indicates that the selection of electrolytic solutions species is important for the aluminum current collector to suppress the pitting corrosion. The corrosion behavior of three kinds of aluminum foils used as the current collector by different surface treatment processes, which include removal of the oxide film (the scratched aluminum foil), exposing at room temperature (the normal aluminum foil) and high temperature oxidation (the heated aluminum foil), in 1molL−1 EtMgBr/THF solution has been investigated by electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR) analysis methods. The pitting resistance of aluminum foils by different surface treatment processes in 1molL−1 EtMgBr/THF solution increases in the order of the scratched aluminum foil<the heated aluminum foil<the normal aluminum foil. These results demonstrate that a layer of dense protective oxide film is important for the aluminum current collector to suppress the pitting corrosion.
The Mediterranean Atmospheric Mercury Cycle System (MAMCS) project was performed between 1998 and 2000 and involved the collaboration of universities and research institutes from Europe, Israel and Turkey. The main goal of MAMCS was to investigate dynamic processes affecting the cycle of mercury in the Mediterranean atmosphere by combining ad hoc field measurements and modelling tasks. To study the fate of Hg in the Mediterranean Basin an updated emission inventory was compiled for Europe and the countries bordering the Mediterranean Sea. Models were developed to describe the individual atmospheric processes which influence the chemical and physical characteristics of atmospheric Hg, and these were coupled to meteorological models to examine the dispersion and deposition of Hg species in the Mediterranean Basin. One intercomparison and four two-week measurement campaigns were carried out over a three-year period. The work presented here describes the results in general terms but focuses on the areas where definite conclusions were unforthcoming and thus highlights those aspects where, in spite of advances made in the understanding of Hg cycling, further work is necessary in order to be able to predict confidently Hg and Hg compound concentration fields and deposition patterns.
The advanced material POLYMET is an innovative high tech polymer with a three-dimensional polymeric structure metallized with an enclosing coating of different kinds of metals or alloys. The result is a range of tailor-made, microporous structures on a designable scale. By varying the metals and alloys, it is possible to draw upon extremely diverse areas of applications such as battery systems, fuel cells, filters or efficient catalysts as well as air regeneration systems, e.g. in aerospace. The three-dimensional structure of metallized high tech woven or non-woven materials or foams causes a lot of advantages such as high conductivity, high corrosion resistance, flexibility or mechanical strength. Therefore, POLYMET is suitable for, e.g. current collectors or gas diffusion layers in energy storage systems. They supply an economic and environmental alternative material to improve functional electrochemical systems.
An all-solid sodium/sulfur battery using poly (ethylene oxide) (PEO) polymer electrolyte are prepared and tested at 90°C. Each battery is composed of a solid sulfur electrode, a sodium metal electrode, and a solid PEO polymer electrolyte. During the first discharge, the battery shows plateau potentials at 2.27 and at 1.76V. The first discharge capacity is 505mAhg−1 sulfur at 90°C. The capacity drastically decreases by repeated on charge–discharge cycling but remains at 166mAhg−1 sulfur after 10 cycles. The latter value is higher than that reported for a Na/poly (vinylidene difluoride)/S battery at room temperature.