batterydata/paper-abstracts huggingface dataset:
In this paper, carbon paper (CP) was modified by three-dimensional reduced graphene oxide (3DrGO/CP) and binders. Based on physical (ﬁeld-emission scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Raman spectroscopy) and electrochemical tests (cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charging/discharging curves), the physical and chemical properties of 3GrGO/CP electrode were investigated. The physical characterization and electrochemical performance analysis indicated that the different binders significantly influenced the hydrophilicity and the wet surface area of electrode. Nitrogen doping three-dimensional reduced graphene oxide facilitates the electron transfer on electrode/electrolyte interface for both oxidation and reduction processes of 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (4-HO-TEMPO), provides more reaction area and reduces concentration polarization. Therefore, the modified carbon paper electrode exhibits better electrochemical activity and reversibility compared with the pristine carbon paper electrode in a methyl viologen (MV)/4-HO-TEMPO redox flow battery (RFB).
Surface modifications with three different procedures were performed on an integrated felt of mesophase carbon fiber (MCF) fired at 600°C. The surface modification procedures were (1) heating in acetylene black powder under a low pressure of oxygen (MOT), (2) vacuum deposition of Ag film on the fiber surface and (3) vacuum deposition of Ag film on the fiber, followed by heating under low pressure of oxygen. The performance of Li insertion/extraction reaction was found improved by any of these modification treatments. The cause of the improvement was examined mainly with impedance spectroscopy analysis (EIS). EIS spectra revealed that both the film resistance and the charge-transfer resistance were decreased remarkably by these surface modifications. Among the three modification procedures, MOT revealed the best improving effect. By comparing the EIS data with the results obtained from the double layer capacity measurement, we concluded that the major cause of the increase in the reaction rate is the activation of the reaction site.
We demonstrate the feasibility of the strain energy harvesting from the automobile tires, powering wireless data transfer with enhanced frame rates, and self-powered strain sensing. For this, we used a flexible organic piezoelectric material for continuous power generation and monitoring of the variable strain experienced by a tire under different driving conditions. Power output of ∼580 µW at 16 Hz (∼112 km/h) from the energy-harvester and mounted on a section of a tire, is sufficient to power 78 LEDs. We further demonstrate that the stored energy was sufficient to power the wireless system that transmits tire deformation data with an enhanced frame rate to control system of a vehicle. Using sensors mounted on a tire of a mobile test rig, measurements were conducted on different terrains with varying normal loads and speeds to quantify the sensitivity and self-powered sensing operation. These results provide a foundation for self-powered real-time sensing and energy efficient data transfer in autonomous vehicles.
This study examines the effects of a graphene nanosheet (GNS) conductive additive on the performance of a highly packed (2.5 g cm−3) lithium-ion battery cathode containing 92 wt% Li1.1(Mn0.6Ni0.4)0.9O2 microspheres (approximately 6 μm in diameter). GNSs, approximately 2.0 nm thick and 0.5–1.0 μm in width, are introduced into an electrode slurry in the form of a dispersion in N-Methyl-2-pyrrolidone. They are substantially smaller than the oxide particles; therefore, their presence exerts no adverse influence on the packing density of the electrode. A small quantity of the GNS additive (≤200 ppm relative to the oxide mass) can significantly increase the overall electronic conductance and improve the conductance uniformity of the oxide electrode, leading to reduced polarization and enhanced specific capacity and rate performance. However, the GNS additive also promotes solid-electrolyte interphase formation, resulting in resistance buildup and capacity deterioration upon cycling. This study is the first to identify such an adverse effect caused by a graphene additive. The interplay between the positive and negative effects has led to an optimal GNS additive content of approximately 100 ppm, enhancing both the rate and cycle life performance.
A technique is developed that combines a new closed-form analytical form of the lumped capacitance model (LCM) and thermography to predict the internal heat generation of a lithium-ion pouch cell. A series of tests is conducted to validate the new technique using a polyimide film heater mounted as a vertical plate in front of an infrared camera. A programmable power supply is used to subject the heater to three types of pre-defined heat profiles. The technique performs very well in reconstructing each known heat profile. The technique is then used to predict the rate of heat generation of a 14.5 Ah lithium iron phosphate cell under different rates of discharge. Compared to the heat rate measured by a calorimeter, the model predicts an average heat rate within 10% for moderate C-rates and lower. For C-rates higher than 2C, a simple correction algorithm is applied due to cell temperature gradients becoming more pronounced.
In this paper, the influences of graphite nanofiber-antler (GNF) adding on LiFePO4 are studied by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), charge/discharge tests, and Ac impedance spectroscopy. In the results, the XRD patterns index to a single-phase material having an orthorhombic olivine-type structure with a space group of Pnma. The 7% GNF-added LiFePO4 demonstrates a higher conductivity than the pure LiFePO4 samples. The electronic conductivity of 7% GNF-added LiFePO4 is 5.32 × 10−3 S cm−1. The CV curves show that the 7% GNF-added LiFePO4 has higher electrochemical reactivity for lithium insertion and extraction than the pure LiFePO4 with the current is 1.65 mA and the voltage between redox peaks is 0.25 V. A discharge capacity of 131.5 mAh g−1 is achieved at a current density of 0.1 mA cm−2 with a slight decline during cycling.
Solid polymer electrolytes composed of poly(ethylene oxide)(PEO), poly(oligo[oxyethylene]oxyterephthaloyl) and lithium perchlorate have been prepared and characterized. Addition of poly(oligo[oxyethylene]oxyterephthaloyl) to PEO/LiClO4 reduced the degree of crystallinity and improved the ambient temperature ionic conductivity. The blend polymer electrolyte containing 40wt.% of poly(oligo[oxyethylene]oxyterephthaloyl) showed an ionic conductivity of 2.0×10−5 Scm−1 at room temperature and a sufficient electrochemical stability to allow application in the lithium batteries. By using the blend polymer electrolytes, the lithium metal polymer cells composed of lithium anode and LiCoO2 cathode were assembled and their cycling performances were evaluated at 40°C.
The 2012 Department of Energy (DOE) budget request significantly reduces fuel cell RD&D funding and would cease to support the Solid State Energy Conversion Alliance (SECA), DOE's solid oxide fuel cell (SOFC) program. This would be a grave mistake considering the US's historic dominance in fuel cell RD&D, exciting recent technological advancements in fuel cells, and clear positive market signals around the globe. In this paper we discuss DOE's energy RD&D policy, how SOFCs address every key DOE strategy, and why recent advances should make SOFCs an integral part of our energy RD&D policy. Moreover, we compare the prospects of low temperature SOFCs with the more common proton exchange membrane fuel cell (PEMFC) in the absence of a hydrogen infrastructure.
Carbonized Zn-(Metal-Organic Framework)MOF- polyaniline composites for high performance of supercapacitor have been developed from zinc acetate, 8-Hydroxyquinoline, and aniline via a simple process. The as-synthesized product has been characterized by X-ray powder diffraction (XRD), Scanning electron microscopy(SEM), Fourier transform infrared spectra (FT-IR), Transmission electron microscope (TEM). The electrochemical properties of carbonized Zn-MOF/polyaniline electrode were investigated by current charge–discharge and cyclic voltammetry. The specific capacitance of MOF/PANI has been approach to be as high as 477 F g−1 at a current density of 1 A g−1.
Haploinsufficiency of the forkhead-box protein P1 (FOXP1) gene leads to a neurodevelopmental disorder termed FOXP1 syndrome. Previous studies in individuals carrying FOXP1 mutations and deletions have described the presence of autism spectrum disorder (ASD) traits, intellectual disability, language impairment, and psychiatric features. The goal of the present study was to comprehensively characterize the genetic and clinical spectrum of FOXP1 syndrome. This is the first study to prospectively examine the genotype-phenotype relationship in multiple individuals with FOXP1 syndrome, using a battery of standardized clinical assessments.
In order to investigate the influence of the dispersion state of electro-conductive additives on the properties of lithium ion batteries, we examined the charge–discharge properties of cathodes prepared with suspensions of ketjen black (KB) dispersed in an organic solvent with different particle sizes. Discharge capacity, durability and resistance to high-current discharge of the cathode prepared from a well-dispersed suspension was higher than those of the cathode prepared with ketjen black powder. Because ketjen black particles in the cathode prepared from a well-dispersed suspension formed a conductive dense-network uniformly, despite the low amount of additive, we concluded that an electro-conductive network made of ketjen black, which can transmit electrons smoothly from active materials to the collector, formed in the cathode when the cathode was prepared from a well-dispersed suspension.
In our efforts to develop low cost high-power Li-ion batteries with excellent safety, as well as long cycle and calendar life, lithium manganese oxide spinel and layered lithium nickel cobalt manganese oxide cathode materials were investigated. Our studies with the graphite/LiPF6/spinel cells indicated a very significant degradation of capacity with cycling at 55°C. This degradation was caused by the reduction of manganese ions on the graphite surface which resulted in a significant increase of the charge-transfer impedance at the anode/electrolyte interface. To improve the stability of the spinel, we investigated an alternative salt that would not generate HF acid that may attack the spinel. The alternative salt we selected for this work was lithium bisoxalatoborate, LiB(C2O4)2 (“LiBoB”). In this case, the graphite/LiBoB/spinel Li-ion cells exhibited much improved cycle/calendar life at 55°C and better abuse tolerance, as well as excellent power. A second system based on LiNi1/3Co1/3Mn1/3O2 layered material was also investigated and its performance was compared to commercial LiNi0.8Co0.15Al0.05O2. Cells based on LiNi1/3Co1/3Mn1/3O2 showed lower power fade and better thermal safety than the LiNi0.8Co0.15Al0.05O2-based commercial cells under similar test conditions. Li-ion cells based on the material with excess lithium (Li1.1Ni1/3Co1/3Mn1/3O2) exhibited excellent power performance that exceeded the FreedomCAR requirements.
A novel solvothermal approach with ascorbic acid as both an antioxidant and a first-time carbon coating source is developed to synthesize LiMn0.4Fe0.6PO4 nano-particles with a uniform particle size distribution around 150nm. A calcination step for the second-time carbon coating and further crystallization is adopted following the solvothermal step. The structures and electrochemical properties of the obtained samples are studied by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transformation infrared, Infrared carbon-sulfur analyzer and galvanostatic cell cycling. Ascorbic acid plays a crucial role in the formation of uniform carbon layer and nano-particles. Compared with single-carbon-coated LiMn0.4Fe0.6PO4 without adding ascorbic acid, the mixed-carbon-coated LiMn0.4Fe0.6PO4 shows much better electrochemical performance. It can deliver specific capacities of 154.8 and 128.5mAhg−1 at 1C and 20C, respectively, at 25°C. Even at −20°C, its specific capacities are 106.6 and 68.8mAhg−1 at 0.2C and 5C, respectively.
A hierarchically Fe2O3@Co3O4 nanowire array is prepared by the aid of hydrothermal synthesis and sacrificial hydrolysis method. The obtained nanowire array shows hierarchical porosity and large surface area. The resulted Fe2O3@Co3O4 nanowire array is evaluated as an anode material for Li ion batteries, which exhibits high capacity and good cycle stability (1005.1 mAh g−1 after 50 cycles at a current density of 200 mA g−1) and an excellent rate performance, mainly owing to the unique hierarchical nanowire architecture and an elegant synergistic effect of two electrochemically active materials. The developed strategy can be readily generalized to construct other multifunctional hybrid nanostructures, which will be promising materials for high-performance electrochemical devices.
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). It has been brought to the attention of the Journal of Parallel and Distributed Computing that an article previously published in JPDC included a large number of references to another journal. It is the opinion of the JPDC Editor-in-Chief and the Publisher that these citations were not of direct relevance to the article and were included to manipulate the citation record. This article is being retracted at the request of the Publisher, on the basis that it violates Elseviers policy regarding citation manipulation. The Editors and editorial board of JPDC were not involved in facilitating this manipulation, as the references were added after acceptance, thus avoiding editorial scrutiny.
What do patients expect from a treatment? A patient-centred approach to treatment is becoming necessary given the choices for invasive treatments for Parkinson’s disease. Patient’s perceptions of severity and expectations from complex therapies have not been studied. We describe the rationale and concept of developing a Patient-Reported Outcome (PRO) tool to assess perceptions of symptom severity and expectations of therapy. We report preliminary findings from use of the tool, association with clinical factors, and illustrate the potential use in individual patients awaiting therapy.
We present simulation results for a simple lattice gas cellular automata model of passivation. The lattice sites representing the corrosion product are produced at the corroding surface and diffuse executing a random walk. Asymmetric simple exclusion rules of the random walk account for an attractive potential between the corrosion product particles. The particles can aggregate and when sufficiently numerous form a compact phase on the corroding surface. The model predicts a transition from the active to passive state when increasing the reactivity of the surface. The transition is characterized by a sudden increase in the surface coverage of the corrosion product interpreted as a passive layer formation. The layer blocks contact of the metal surface with the environment and reduces the corrosion rate. The model reproduces the known paradox of passivity—the surface must be reactive enough for the layer to form. A further increase in the bare reactivity reduces largely the observed reaction rate. The simulations yield information on the morphological changes of the surface layer before and after the transition. In terms of the corrosion current, the active state is described by the current increase with the polarizing potential according to the Tafel law while in the passive state the current is independent of the anodic potential. Our simple model reproduces principal features of passivation.
Many engineering activities, including mechatronic design, require that a multidomain or ‘multi-physics’ system and its control system be designed as an integrated system. This contribution discusses the background and tools for a port-based approach to integrated modeling and simulation of physical systems and their controllers, with parameters that are directly related to the real-world system, thus improving insight and direct feedback on modeling decisions.
Glassy cathode deposition on solid electrolyte substrate applied to lithium middle-temperature all-solid-state batteries was investigated. The 30Li2O·47.5V2O5·22.5B2O3 (LBV) glassy cathode is crystallized on Li7La3Zr2O12 (LLZ) solid electrolyte substrate at various temperatures (650–850 °C) and holding times (0.5–5 min). The phase composition of the crystallized glass and vanadium oxidation state are determined by the XRD and XPS analysis. The different lithium vanadates form at all studied temperatures, and the boron-containing phases appear at temperatures greater than 750 °C. SEM investigation shows that the lithium borate-vanadate glass crystallized at 750 °C to create the optimal interface and close contact between the electrode and the electrolyte. Processing at lower temperatures does not allow for good contact, and processing at higher temperatures leads to the interaction between the cathode material and ceramic electrolyte. The optimal mode of 30Li2O·47.5V2O5·22.5B2O3 glassy cathode deposition on the substrate is found to be glass powder annealing for 0.5 min at 750 °C. This LBV|LLZ cell has the highest conductivity and the lowest polarization resistance on the cathode|electrolyte interface. The universality of this deposition mode is demonstrated using Li3.65Al0.05Ge0.95P0.2O4 ceramic substrate as an example. Thus, the LBV glass can be used for the formation of an optimal interface with other lithium-ion solid electrolytes.
is a Specialist in Engineering and Simulation at Salzgitter Mannesmann Forschung GmbH in Salzgitter (Germany).
The surface morphologies of lead dioxide layers, which were formed on a pure lead substrate and the Pb–Sb a (100ppm–3%) alloy substrate, were directly observed with the electrochemical atomic force microscope (EC-AFM) in 1.250g/cm3 sulfuric acid electrolyte and then they were analyzed with X-ray diffraction (XRD). The particle size of the lead dioxide became significantly smaller with the increase of the amount of antimony in the substrate alloy. From this result, it was considered that such small particle size serves to increase the reaction area of the positive electrode and the total electrical contact area between the positive active material (PAM) particles. Also, the interface resistance between grid and the PAM can become lower, if the density of the corrosion layer formed around the grid were to be higher for the small particles. By XRD analysis, it was found that the inter-atomic distance of the lead dioxide on the Pb–3wt.% Sb alloy substrate shrank compared to that on a pure Pb substrate.
The open circuit voltage (OCV) of solid oxide fuel cells is generally overestimated by the Nernst equation and the Wagner equation, due to the polarization losses at electrodes. Considering both the electronic conduction of electrolyte and the electrode polarization losses, we express the OCV as an implicit function of the characteristic oxygen pressure of electrolyte (p* [atm], at which the electronic and ionic conductivities are the same), and the relative polarization resistance of electrodes (r c = R c/R i and r a = R a/R i, where R i/c/a [Ωcm2] denotes the ionic resistance of electrolyte, and the polarization resistances of cathode and anode, respectively). This equation approaches to the Wagner equation when the electrodes are highly active (r c and r a → 0), and approaches to the Nernst equation when the electrolyte is a purely ionic conductor (p* → 0). For the fuel cells whose OCV is well below the prediction of the Wagner equation, for example with thin doped ceria electrolyte, it is demonstrated that the combination of OCV and impedance spectroscopy measurements allows the determination of p*, R c and R a. This equation can serve as a simple yet powerful tool to study the internal losses in the cell under open circuit condition.
The LiMnPO4 cathode material is a good candidate for rechargeable lithium ion batteries because of high voltage (4.1 V), high thermal stability and no toxicity. However, the rate performance of this material is extremely low when compared to the conventional LiMO2 (M = Ni or Co) or LiFePO4. In this study, the primary particle size was reduced by a hydrothermal synthesis, and we obtained LiMnPO4 particles with sizes less than 40 nm. The sample exhibited an excellent rate capacity, which was 136 mAh g−1 at 5 C and 120 mAh g−1 at 10 C. We also revealed the effect of the LiMnPO4 particle size on the battery by introducing STEM-EELS, which was expected to allow for the direct microscopic observation of the lithium state in the particles during the charge-discharge process. With the EELS analysis, it was clarified that the lithium diffusion distance from the inside to the surface of the primary particles had to be reduced down to about 20 nm to achieve the high rate performance.
This paper describes a non-destructive method to measure the tilt angle (Φ) of a tree's structural root zone as it tilts under winds or static pulling. This method records both magnitude and direction of the dynamic tilt response of the tree root plate. A tri-axial accelerometer is used as a tilt sensor and is attached to the base of the tree trunk at ground level. Dynamic root plate tilt can be measured using 20Hz sampling. The tilt sensor was calibrated in a laboratory then used in field tests on trees that were statically loaded, then on trees subject to natural wind conditions. The maximum structural root zone tilt recorded during static pulling tests was 0.60°. Under natural wind conditions the maximum root plate tilt recorded was 0.88°. Some practical limitations of the sensor in the field due to the battery capacity and reliability are discussed.
This paper examines the effect of the electrical double layer on the performance of a lithium ion battery electrochemical cell. We begin by introducing the Poisson Nernst–Planck equations of electrochemistry to describe ion transport within a representative liquid solvent and derive an expression for the current–voltage relationship in the electroneutral liquid within the separator pores. Different assumptions about the electrical double layer lead to variation of the lithium ion concentration profiles in the liquid electrolyte, which alter the cell voltage during discharge. The contribution of the electrical double layer to the cell overpotential is combined with the bulk liquid potential difference and a simplified treatment of the electrode solid phase to obtain an expression for the time-varying cell terminal voltage. We conclude by presenting experimental data for a cell using a graphite anode and lithium iron phosphate cathode to validate the new model, which includes electrical double layer effects, and construct modifications to the model to compensate for resistive effects that are associated with the cathode solid phase.
The low temperature behaviors of Li/TEGDME/S cell was examined using discharge curves, SEM and impedance spectra. The first discharge capacity of Li/S cell with tetra(ethylene glycol) dimethyl ether (TEGDME) electrolyte was 1303mAhg−1-sulfur at 20°C, but 357mAhg−1-sulfur at low temperature of −10°C. The low temperature discharge characteristic is improved by adding 1,3-dioxolane (DOXL) and methylacetate (MA) to TEGDME electrolyte. The optimum composition of mixed electrolyte is MA–DOXL–TEGDME (5:47.5:47:5, v/v). The Li/S cell using the optimum electrolyte has the first discharge capacity of 994 and 1342mAhg−1-S at −10 and 20°C, respectively.