batterydata/paper-abstracts huggingface dataset:
This work presents the feasibility of monitoring state of charge (SoC) and state of health (SoH) of lithium-ion pouch batteries with acousto-ultrasonic guided waves. The guided waves are propagated and sensed using low-profile, built-in piezoelectric disc transducers that can be retrofitted onto off-the-shelf batteries. Both experimental and analytical studies are performed to understand the relationship between guided waves generated in a pitch-catch mode and battery SoC/SoH. The preliminary experiments on representative pouch cells show that the changes in time of flight (ToF) and signal amplitude (SA) resulting from shifts in the guided wave signals correlate strongly with the electrochemical charge-discharge cycling and aging. An analytical acoustic model is developed to simulate the variations in electrode moduli and densities during cycling, which correctly validates the absolute values and range of experimental ToF. It is further illustrated via a statistical study that ToF and SA can be used in a prediction model to accurately estimate SoC/SoH. Additionally, by using multiple sensors in a network configuration on the same battery, a significantly more reliable and accurate SoC/SoH prediction is achieved. The indicative results from this study can be extended to develop a unified guided-wave-based framework for SoC/SoH monitoring of many lithium-ion battery applications.
Co3O4 nanosheets and Co3O4/carbon allotrope (Co3O4/C) composites have been successfully synthesized and investigated as anode materials for sodium ion batteries (SIBs). Microstructure characterizations have been performed to confirm the formation of Co3O4/C nanohybrids. It has been found that the as-prepared Co3O4/C composites exhibit excellent sodium storage properties including superior cycle stability and rate capability, delivering reversible capacities of 436.9 (for Co3O4/GNSs), 388.5 (for Co3O4/CNTs), and 340.1 mA h g−1 (for Co3O4/CB) at a current density of 50 mA g−1 after 100 cycles, respectively, which are much higher than that of the bare Co3O4 counterpart (219.7 mA h g−1 at 50 mA g−1 after 100 cycles). Moreover, reversible capacities of 231 mA h g−1 for Co3O4/GNSs is realized at a high rate of 3.2 A g−1. The improved electrochemical performance is considered due to the introduction of the carbon-based materials, which not only serve as efficient buffering matrixes to decrease in volume expansion during cycling but also improve the electrode conductivity.
In the first part of the present project, electrochemical characterisation techniques for several expander materials were developed and applied to a total of 19 potential expander candidates, selected from various different sources: conventional and novel expanders, new synthetic products, and natural substances. From the obtained results, seven most effective candidates were selected for further testing in real VRLA single cells. In these tests, all the candidates have been tested at the 0.2% concentration level in the paste, and for three selected candidates, alternative levels of the expander, carbon black and barium sulphate have been additionally tested. After the cell formation, initially a series of preliminary discharges at different discharge rates were carried out in order to characterise the initial performance of each formulation. Then, the single cells were submitted to the initial tests previous to the EUCAR ECE15L cycling specification for electric vehicles and then to the ECE15L cycle life test at 80% depth-of-discharge (DoD). The results of the preliminary discharges showed that differences up to 10–13% can be found in the initial capacity delivered by the different formulations at the test rates. The results of the cycle life tests showed that all the tested variables (type/concentration of the expander, concentration of carbon black and concentration of barium sulphate) usually caused a variation in the cycle life behaviour, although the amount of this variation was strongly dependent on the considered expander. The most significant effect was observed when the carbon black level was increased, producing remarkable improvements both in the initial discharge capacities and in the cycle life performance.
Silicon is a promising candidate for the anode material in lithium ion batteries due to its ultrahigh theoretical capacity of 4200mAhg−1, which is approximately ten times larger compared to current commercial graphite anodes. However, the pulverization and capacity fading caused by the dramatic volume changes during cycling are still challenging its widespread application. To address these problems, a novel Si@C heterostructure with tunable preformed voids between Si core and carbon shell is synthesized via a flexible and tunable route. When evaluated for their electrochemical properties, these hollow Si@C spheres show enhanced electrochemical properties.
This article aims to offer a critical overview of selected literature on capacitive and non-capacitive faradaic charge storage. It is particularly relevant to the concept of pseudocapacitance that is generally described as a result of fast surface faradaic processes. In general, faradaic processes represent electron transfer reactions at the interface between an electrode and its contacting solid or liquid electrolyte phase that is able to accept or donate electrons. Obviously, not all faradaic processes can be associated with pseudocapacitance. The question is how to differentiate pseudocapacitance related faradaic charge storage from the others. Therefore, attempts have been made to apply the band model for semiconductors to account qualitatively for the origin of pseudocapacitance. Capacitive and non-capacitive faradaic processes are then proposed to define and differentiate different charge storage mechanisms in supercapacitor and battery. On the other hand, the unequal electrode capacitance approach and the use of Ca2+ in aqueous electrolytes are discussed in relation with enhanced energy capacity of supercapacitors. In addition, the principle of supercapattery as a hybrid device is explained with recent literature examples.
The thin-film electrode has been regarded as one of the desirable options for the vanadium redox flow battery. However, most of the thin-film electrodes developed to date suffer from high mass transport resistance and deliver unsatisfactory performance. In this work, we proposed a dual-layer thin-film electrode, consisting of a backing layer and a catalyst layer, for flow batteries. The backing layer with larger pores is adapted to improve the concentration distribution as well as to provide mechanical support while the catalyst layer with smaller pores provides sufficient active sites. The electrospun fiber mat is adopted as catalyst layer and backing layers in the study include carbon paper, carbon cloth and graphite felt. It is showed that carbon cloth supported electrospun fiber mat electrode demonstrates an energy efficiency of 76.1% at the current density of 240 mA cm−2, which is much higher that achieved by conventional electrospun fiber mat electrodes (61.9%). After optimizations of flow field designs and key operational parameters, the energy efficiency of battery with dual-layer structured electrodes can reach as high as 80.2% at a current density of 240 mA cm−2. In addition, the present battery can stably operate for more than 800 cycles without obvious decay.
Primary care is the principal clinical setting for the management of depression. However, significant shortcomings have been detected in its diagnosis and clinical management, as well as in patient outcomes. We developed the INDI collaborative care model to improve the management of depression in primary care. This intervention has been favorably evaluated in terms of clinical efficacy and cost-effectiveness in a clinical trial. Our aim is to bring this intervention from the scientific context into clinical practice.
We report here a study of phosphazene polymer and oligomer electrolyte infiltration into high surface area titanium dioxide electrodes and its effect on the performance of dye-sensitized solar cells. The effects of different cell assembly procedures on the electrochemical properties are examined, as well as the infiltration of electrolytes based on poly[bis(2-(2-methoxyethoxy)ethoxy)phosphazene] (MEEP), hexakis(2-(2-methoxyethoxy)ethoxy)cyclotriphosphazene (MEE trimer), and a linear short chain analogue into conventional titanium dioxide electrode mesoporous (nanosphere) films, microcolumns and nanowires. The effects of temperature, co-solvents, and the order of addition of the electroactive components are found to affect both the conductivity of the electrolytes and the electrochemical performance of the cells. Cross-sectional scanning electron microscopy (SEM) imaging is employed to examine the degree of electrolyte infiltration into the nanostructured electrodes as a function of filling conditions. Using these techniques, conditions are identified for achieving a high degree of pore filling by the three electrolyte systems. Increased power conversion efficiency is obtained when iodine is introduced after the heating and evacuation procedures required for maximum infiltration.
Effect of lithium difluoro(oxalato)borate and heptamethyldisilazane with different concentrations as additives on cycling performance of LiMn2O4 is studied and evaluated at 25°C and 60°C by cyclic voltammetry (CV) test, linear sweep voltage (LSV) test, TG-DSC analysis, conductivity, electrochemical impedance spectroscopy (EIS) and charge–discharge measurements. The results show that the addition of heptamethyldisilazane does not influence the electrochemical performance of LiMn2O4 electrode and the conductivity of original electrolyte basically. What is more, 2vol.% HMDS can apparently improve the cycling performance of LiMn2O4 at room and elevated temperature, while 6vol.% HMDS and 0.2M LiDFOB in the electrolyte have not achieved the desired effect, and even deteriorated the cycling performance of LiMn2O4/Li half cells. When the concentration of the additive is 2vol.%, the battery of LiPF6-based electrolyte with HMDS additive shows perfect cycling performance at room temperature at 2 C rate, and the capacity fading is only 3.8mAh g−1 after 200cycles.
The paper provides an overview of the historical development of wind energy technology and discusses the current world-wide status of grid-connected as well as stand-alone wind power generation. During the last decade of the twentieth century, grid-connected world-wide wind capacity has doubled approximately every three years. Due to the fast market development, wind turbine technology has experienced an important evolution over time. An overview of the different design approaches is given and issues like power grid integration, economics, environmental impact and special system applications, such as offshore wind energy, are discussed. Due to the complexity of the wind energy technology, however, this paper mainly aims at presenting a brief overview of the relevant wind turbine and wind project issues. Therefore, detailed information to further readings and related organisations is provided. This paper is an updated version of the article ‘Wind Energy Technology and Current Status: A Review’, published in Renewable and Sustainable Energy Reviews, 4/2000, pp. 315–374. This update was requested by Elsevier due to the large interest in wind power.
As a positive electrode material for Li-ion batteries, xLi2MnO3·(1− x)LiMO2 (M=Mn, Ni, Co) boasts various advantages compared to LiCoO2, such as higher specific charge (∼250Ah/kg) and lower cobalt content. However, the oxygen release reaction at ∼4.5V vs. Li+/Li is not fully understood. xLi2MnO3·(1− x)LiMO2 has been characterized by a combination of complementary methods, including electrochemical cycling at different temperatures, differential electrochemical mass spectrometry (DEMS), in situ pressure measurement, and in situ temperature measurement. The reaction at ∼4.5V vs. Li+/Li leads to the exothermic release of oxygen and a significant pressure build-up in the cell. Despite this, the electrochemical performance of the material is very promising. Finally, it is shown that the cells should be operated close to room temperature.
The cause of the memory effect observed in alkaline-type rechargeable batteries such as nickel–cadmium and nickel–hydrogen batteries was studied using a positive capacity-limited nickel–cadmium cell and AAA-type commercially available nickel–cadmium and nickel–hydrogen batteries. From the X-ray diffraction (XRD) analysis, γ-NiOOH was observed on the nickel electrode in a charged state after repeating shallow discharge cycling of the cells or overcharging. This γ-NiOOH is initially formed at the collector side of the electrode and it then grows to the solution side during shallow discharge cycling. When the amount of γ-NiOOH formed is small, only β-NiOOH can be detected by conventional XRD, even when the memory effect is observed. In this case, γ-NiOOH can be detected by shaving the surface of the electrode, using an emery paper to remove the β-NiOOH covering. This γ-NiOOH disappeared within a few cycles of the normal charge–discharge cycling and the memory effect disappeared. It is concluded that the cause of the memory effect is mainly due to the formation of γ-NiOOH.
Development of electric mobility and sustainable energy result in new technologies such as contactless electric vehicle charging and roadway energy harvesting methods, but also self-healing asphalt roads. By combining these technologies a new concept of Future Sustainable Roads for Electric Mobility is created and presented in the paper. This paper bridges the gap created by these unilateral technology developments using a multi-disciplinary approach including placing cautions when necessary and suggesting viable alternatives for optimal utilization of these energy transfer and conversion techniques. Through theoretical analysis, simulations, and tests on lab-scale experimental prototypes, the impact of our proposal is showcased. Thermal and loss models are developed for self-healing asphalt. Also, integration study of solar roads and contactless charging is performed. Applying the insight gained from the results, it is discussed how some challenges also pave a way towards interesting opportunities, for instance, infrastructure sharing for material use optimization and efficient mosaic integration. Finally, an economic viability case study is presented for a future Dutch highway with such newly emerging components.
TiO2–graphene nanosheets (GNS) composites are prepared via an in situ chemical synthesis method, which enables a homogenous dispersion of TiO2 nanoparticles on the graphene nanosheets. The obtained TiO2–GNS composites are anatase-GNS, while TiO2 is nanosized rutile without the incorporation of GNS. The resulting TiO2–GNS composites are employed as anode materials for lithium-ion batteries, showing a high initial reversible capacity of 306mAhg−1 as well as a good cycling stability. The TiO2–GNS composites can deliver 60mAhg−1 at a current rate as high as 5Ag−1 and demonstrate negligible fade even after 400 cycles. The superior electrochemical performances of the TiO2–GNS composites can be attributed to their unique structures, which intimately combine the conductive graphene nanosheets network with uniformly dispersed TiO2 nanoparticles. The TiO2–GNS composites could be promising candidate materials for high-power, low-cost, and environmentally friendly anodes for lithium ion batteries.
Various hypotheses about the role of the anterior temporal lobe (ATL) in language processing have been proposed. One hypothesis is that it binds the semantic/conceptual properties of words, functioning as a hub for linking modality-specific conceptual properties of objects. This hypothesis predicts that damage to ATL would give rise to impaired conceptual knowledge of all categories. A related school of hypotheses assumes that the left ATL is critical for lexical retrieval, with different sub-regions potentially important for different categories of items. We examined these hypotheses by studying a case of surgical resection of left ATL due to a low-grade glioma (LGG). Thorough language assessments performed four months after the operation revealed the following profile: the patient showed intact conceptual knowledge for all categories of items tested using both accuracy and response latency measures; he suffered from name retrieval deficits for proper names (people and place names) and artifacts (including tools), but showed no name retrieval difficulties for animate things. This pattern of results challenges both target hypotheses about the role of ATL in language processing tested here.
In this study, the effect of addition of zinc and erbium on the corrosion behavior of magnesium alloys in phosphate buffer saline (PBS) solution was studied. Also, the fluoride coatings were developed and their corrosion behavior has been studied. These alloys were synthesized using disintegrated melt deposition (DMD) technique followed by hot-extrusion. Results show that the addition of Zn and Er reduced the grain size of as-extruded alloys and it has enhanced the corrosion resistance. Compact fluoride coatings were developed, their microstructural characterization was carried out and they further enhance the corrosion behavior.
Nickel oxide (NiO) was synthesized using several methods and the various physical characteristics observed were correlated to differences in electrocatalytic activity, specifically relating to the oxidation of methanol in alkaline media. Room temperature NaOH-precipitated NiO showed the highest activity and stability towards methanol oxidation in hydroxide (0.005M KOH) and carbonate (0.1M Na2CO3) media of similar alkalinity. Rapid degradation of NiO electrodes was attributed to microcracking and disintegration associated with the formation of the γ-NiOOH/α-Ni(OH)2 redox couple, in addition to repeated scans through the oxygen evolution reaction region. Carbonate electrolytes also exhibited average current ranges 3–4 times higher and charge transfer resistances around 85% lower than hydroxide electrolytes. This suggests carbonate may provide a better medium in terms of higher activity and more moderate alkalinity for electrochemical reactions than hydroxide solutions.
The formation of cobalt metal organic frameworks (Co-MOFs) in different solvents and mixture is studied systematically through solvothermal method. The synthesized Co-MOFs are characterized with X-ray diffraction, Field emission scanning electron microscope and Brunauer-Emmett-Teller surface analyzer to know about its crystal nature, morphology and porosity, respectively. Based on the obtained results, a possible formation mechanism of Co-MOFs has been described with respect to nucleation rate and pH. The electrochemical properties of as prepared Co-MOFs are studied in 3 M KOH for electrode material of supercapacitors. A maximum specific capacitance of 958.1 F g−1 is achieved for Co-MOF/D-E (Co-MOF synthesized in DMF/Ethanol) at a current density of 2 A g−1. Simultaneously, the capacitance retention is maintained as high as 92.3%, even after 3000 cycles. The present study demonstrates that synthesis of Co-MOF with large surface area and micropore volume could be possible using DMF/EtOH mixture solvent. The hybrid structure of nanoneedles with sharp edge nanorods offer more active sites for electrochemical reaction and ensure a higher charge storage capacity than other synthesized Co-MOFs in this work.
Objective: To explore effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex (M1) on motor excitability and basic motor behavior in humans. Design and Methods: Seven normal volunteers underwent 1 Hz rTMS of the hand representation of the right M1 for 15 min at an intensity of 115% of the individual resting motor threshold. The effects of rTMS on motor excitability were assessed by monitoring changes in individual resting motor threshold and input-output curves of motor evoked potentials (MEPs) in the flexor pollicis brevis, first dorsal interosseus, abductor digiti minimi and biceps brachii muscles. Changes in basic motor behavior were studied by measuring maximal and mean peak force and peak accelerations of thumb flexions and abductions of the fifth finger before and after rTMS. Results: rTMS produced a significant increase in resting motor threshold and a significant suppression of MEP input-output curves that persisted for 30 min. The suppressing effect was restricted to the hand motor representation which was the prime target of the stimulation procedure, and there were no significant effects on the biceps representation. Peak force and peak acceleration were not affected while the motor representations of muscles involved in the behavioral measurements were significantly suppressed by rTMS. Conclusions: Low-frequency rTMS of M1 transiently depresses motor excitability but this does not affect basic motor behavior. This is relevant for the therapeutic use of low-frequency rTMS in disorders with abnormal cortical excitability.
Terephthalate (C8H4O4 2−) moiety with stable oxidized and reduced states is widely employed as the organic anode in batteries. However, along with the dissolution problem, the representative lithium terephthalate (Li2TP) exhibited unsatisfactory cyclic and rate capability. Herein, based on the calculated and experimental results, we demonstrated that potassium terephthalate (K2TP) possesses superior cyclic and rate capability in Li-ion batteries. On one hand, due to the larger radius of K+ ion, K2TP exhibits more stable lattice architecture than Li2TP for the better size matching between cations and anions; On the other hand, K+ ion in K2TP could remain electrochemical inertness even its standard redox potential (−2.931V) is higher than Li+ ion (−3.040V). Meanwhile, the KO bond in K2TP is calculated to be more ionic while the LiO bond in Li2TP has more covalent character. The ionic KO bond of K2TP could further enhance its dissolution resistance against non-polar electrolyte. Indeed, after its electronic conductivity and particle dispersity were improved by mixing with graphene, the modified K2TP anode could exhibit very stable capacity of ∼122mAhg−1 at 8C for 500 cycles, which is comparable or even superior to the state-of-the-art Li-ion batteries currently reported for small organic molecules.
Sodium ion battery is a potential sustainable energy storage system due to its abundance and low cost. To date, some Na-storage anode materials have achieved long life span, but the rate performance still remains insufficient. Herein, we show that in some linear ether-based electrolytes, graphite can not only render unprecedented cyclability (∼6000 cycles), but also exhibit ultrahigh rate capability (up to 10 A g−1), along with a reversible capacity of ∼110 mAh g−1. By combining electrochemical measurements and structural analysis (e.g. in situ Raman and ex situ XRD measurements), we reveal that graphite undergoes a stage-evolution mechanism induced by the insertion of solvated sodium ions. Furthermore, kinetic studies have shown that this process accompanies with an intercalation pseudocapacitive behavior, which should be responsible for the obtained superior electrode properties.
The aim of this study was to assess how the glycaemic potency (blood glucose (BG)-raising potential) of breakfast is associated with cognitive function (CF) in school children, taking into account important confounders, including iron status, underlying physiological adaptations and socio-economic status.