batterydata/paper-abstracts huggingface dataset:
Capacity and resistance are state-of-health (SOH) indicators that are essential to monitor during the application of batteries on board electric vehicles. For state-of-health determination in laboratory environment, standard battery performance tests are established and well-functioning. Since standard performance tests are not available on-board a vehicle, we are developing a method where those standard tests are applied virtually to a support vector machine-based battery model. This data-driven model is solely based on variables available during ordinary electric vehicle (EV) operation such as battery current, voltage and temperature. This article contributes with a thorough experimental validation of this method, as well as the introduction of new features – capacity estimation and temperature dependence. Typical EV battery usage data is generated and exposed to the suggested method in order to estimate capacity and resistance. These estimations are compared to direct measurements of the SOH indicators with standard tests. The obtained estimations of capacities and instantaneous resistances demonstrate good accuracy over a temperature and state-of-charge range typical for EV operating conditions and allow thus for online detection of battery degradation. The proposed method is also found to be suitable for on-board application in respect of processing power and memory restrictions.
Highly crystalline spinel LiMn2O4 was successfully synthesized by annealing lithiated MnO2 at a relative low temperature of 600°C, in which the lithiated MnO2 was prepared by chemical lithiation of the electrolytic manganese dioxide (EMD) and LiI. The LiI/MnO2 ratio and the annealing temperature were optimized to obtain the pure phase LiMn2O4. With the LiI/MnO2 molar ratio of 0.75, and annealing temperature of 600°C, the resulting compounds showed a high initial discharge capacity of 127mAhg−1 at a current rate of 40mAhg−1. Moreover, it exhibited excellent cycling and high rate capability, maintaining 90% of its initial capacity after 100 charge–discharge cycles, at a discharge rate of 5C, it kept more than 85% of the reversible capacity compared with that of 0.1C.
Rechargeable aqueous sodium-ion batteries (SIBs) are urgently pursued as a low-cost candidate for grid-scale storage of intermittent renewable energies. NASICON-type NaTi2(PO4)3 holds great promises as anode material for aqueous SIBs owing to the high theoretical capacity and low redox potential, but being severely challenged by poor cycling performance and low reaction kinetics. Herein, graphene-integrated NaTi2(PO4)3/C composite is prepared with a facile sol-gel approach as anode material for aqueous SIBs. Electrochemical properties of the material in high-concentration aqueous electrolyte (6M NaClO4) are systematically investigated by using cycling voltammetry, galvanostatic technique and electrochemical impedance spectroscopy. It is found that it shows an improved charge/discharge performance with a high practical capacity of 104.6mAhg−1 at 100mAg−1, excellent high-rate capability with a reversible capacity of 88.0mAhg−1 at 2000mAg−1, and good cycling stability with 92% capacity retention after 100cycles. The improved electrochemical performance is attributed to the synergetic contribution of carbon-blending nanostructure and high-concentration electrolyte, which largely enhances structural stability and reaction kinetics of the material. In addition, the redox mechanism is discussed based on experimental results from cyclic voltammetry and X-ray diffraction technique.
The frontotemporal cortical network is associated with behaviours such as impulsivity and aggression. The health of the uncinate fasciculus (UF) that connects the orbitofrontal cortex (OFC) with the anterior temporal lobe (ATL) may be a crucial determinant of behavioural regulation. Behavioural changes can emerge after repeated concussion and thus we used MRI to examine the UF and connected gray matter as it relates to impulsivity and aggression in retired professional football players who had sustained multiple concussions. Behaviourally, athletes had faster reaction times and an increased error rate on a go/no-go task, and increased aggression and mania compared to controls. MRI revealed that the athletes had (1) cortical thinning of the ATL, (2) negative correlations of OFC thickness with aggression and task errors, indicative of impulsivity, (3) negative correlations of UF axial diffusivity with error rates and aggression, and (4) elevated resting-state functional connectivity between the ATL and OFC. Using machine learning, we found that UF diffusion imaging differentiates athletes from healthy controls with significant classifiers based on UF mean and radial diffusivity showing 79–84 % sensitivity and specificity, and 0.8 areas under the ROC curves. The spatial pattern of classifier weights revealed hot spots at the orbitofrontal and temporal ends of the UF. These data implicate the UF system in the pathological outcomes of repeated concussion as they relate to impulsive behaviour. Furthermore, a support vector machine has potential utility in the general assessment and diagnosis of brain abnormalities following concussion.
Vanadium oxides (VOx·nH2O) with long cycle-life for Li-ion supercapacitors have been successfully synthesized by means of the microwave-assisted hydrothermal synthesis (MAHS) method, a faster and more energy-saving method than the conventional hydrothermal synthesis. Such oxides show capacitor-like, lithium-ion intercalation/de-intercalation responses in aqueous media. Although electrochemical activation is required to reveal the capacitor-like behavior of VOx·nH2O, doping Li ions by adding LiCl into the precursor solution not only effectively shortens the activation time but also enhances the specific capacitance of VOx·nH2O. This kind of materials shows the promising application potential in the aqueous-based Li-ion supercapacitors. X-ray diffraction (XRD), Raman spectroscopic, and X-ray photoelectron spectroscopic (XPS) analyses are employed to identify the fine tune-up in microstructures of various VOx·nH2O.
We tested 4.2V Li-ion polymer batteries (LIPB) with physical gel electrolyte, poly(vinylidene fluoride) (PVDF), 4.4V LIPB and 4.4V Li-ion batteries (LIB) with a liquid electrolyte. The discharge capacity of the 4.4V LIPB reached 520Whl−1 which was 9% higher than that of the 4.2V LIPB. The 4.4V LIPB had a high capacity retention ratio of 91.4% at 3C because of the excellent ion conductivity of the PVDF gel. The capacity retention ratio of the 4.4V LIPB was 82% after 500 cycles, which is comparable to those of some commercial LIBs. The 4.4V LIPB retained its original thickness even after many cycles and after being stored at 90°C, whereas the 4.4V LIB swelled by over 20%. Peaks in the FT-IR spectrum of the discolored separator in the 4.4V LIB after storage were assigned to CC double bonds, suggesting that the separator in direct contact with the 4.4V cathode had been oxidized. The PVDF gel electrolyte not only had a high ionic conductivity but also completely suppressed oxidation. The 4.4V LIPB with PVDF gel electrolyte has properties suitable for practical cells, namely, high energy density, high permanence and it is safe to use.
Children with developmental coordination disorder (DCD) have deficits in working memory, but little is known about the everyday memory of these children in real-life situations. We investigated the everyday memory function in children with DCD, and explored the specific profile of everyday memory across different domains. Nineteen children with DCD and 19 typically developing (TD) children participated in the study. Their everyday memory performance was evaluated using the Rivermead Behavioral Memory Test for Children, which showed that 52.6% of the children with DCD had everyday memory deficits. The overall everyday memory scores of the DCD group were significantly lower than those of the controls, particularly in the verbal and visual memory domains. Pearson correlation analysis indicated significant associations between verbal intelligence and memory scores. Analysis of covariance with verbal intelligence as a covariate showed no significant differences between groups in memory scores. Mediator analysis supported the notion that everyday memory deficits in children with DCD were fully mediated through verbal intelligence. We provide evidence of everyday memory deficits in most of the children with DCD, and hypothesize that language abilities are their underlying cause. The clinical implications of these findings and recommendations for additional research are discussed.
A ternary polyaniline/sulfur/acetylene black (PANi@S-C) composite cathode with variable PANi content has been synthesized by a continuous two-step liquid phase route. Different ratios of the PANi@S-C composite are characterized by SEM, TEM, FTIR, XRD and electrochemical methods. The conductive polyaniline plays multiple roles in the composite, acting as a conducting additive and a porous adsorbing agent. It is uniformly coated onto the surface of a S-C composite powder to form a core/shell structure, which significantly enhances the electrochemical performance and cycle life of the sulfur cells. The PANi@S-C composite with 12.5wt% PANi presents optimum electrochemical performance, where the initial discharge specific capacity is 1257mAhg−1 and remains ∼600mAhg−1 after 100 cycles at 0.16mAcm−2. After a rate test from 0.1 to 1mAcm−2, the cell remained at ∼600mAhg−1 sulfur after 50 cycles when the current density returned to 0.1mAcm−2.
Increase in use of renewable energy such as solar and wind has created challenges in balancing load. Renewable energy intermittency can be addressed with different solutions and technologies. Using Electric Energy Storage (EES) has been an approach which has been studied extensively in the recent years. This paper reviews the storage technologies leveraging both technical papers on technologies as well as other reviews of such technologies done by other researchers. The contribution of this paper is in two areas. First the use of a case study demonstrates how different approaches can address different challenges. Second contribution is the review of evaluation factors and methods of such technologies resulting in a proposed framework.
In this paper, a series of Ce-doped Li3V2(PO4)3/C composite cathode materials for Li-ion batteries were synthesized by a facile and fast microwave assisted sol–gel route. The investigation of the influence of Ce doping on the structural and electrochemical characteristics of Li3V2(PO4)3/C shows that the resulting composite exhibits smaller particle size, lower electron-transfer resistance, and faster lithium ion migration, which are attributed to improved lithium ion transfer by the Ce doping. At low charge/discharge rates, the Ce-doped Li3V1.98Ce0.02(PO4)3/C composite delivers a stable specific capacity of ∼170 mAh g−1 for over 100 cycles. At high rates (e.g. 10C), the Ce-doped composite is still able to deliver stable capacities of up to ∼120 mAh g−1 which is ∼60% greater than its un-doped counterpart.
In this paper, a versatile facile route to synthesize mesoporous hollow-structured metal oxides is demonstrated using sulfonated polystyrene (SPS) microspheres as hard templates. SEM and TEM images show that the Fe2O3, Co3O4 and NiO hollow microspheres are self-assembled by nanorods, nanoparticles and nanosheets, respectively. Hollow and mesoporous structures not only provide enhanced mechanical stabilities to buffer the large volume changes during the charge/discharge processes, but also provide large specific areas for sufficient penetration of electrolyte, thus leading to an excellent cyclic stability and rate capability. As proofs-of-concepts, all of the hollow and mesoporous metal oxides (Fe2O3, Co3O4 and NiO) deliver high initial discharge capacities and good capacity retentions (>80%) after more than 100 cycles in half cells. Most important of all, these assembled full-cells (MxOy(M=Fe, Co, Ni)/LiCoO2) also delivere excellent electrochemical performances. This work clearly demonstrates that the MxOy(M=Fe, Co, Ni)/LiCoO2 configuration are promising alternative high power-density energy storage devices in the near future.
Restrictive bariatric operations are efficient with low morbidity but entail high rate of failure on follow up of several years. We present our experience in laparoscopic revision of patients who previously underwent silastic ring vertical gastroplasty (SRVG) into laparoscopic sleeve gastrectomy (LSG) and Roux-en-Y gastric bypass (LRYGB).
Consent forms for cataract surgery performed at Burnley General Hospital (BGH) and Blackburn Royal Infirmary (BRI) from October 4 to December 7, 2004, were prospectively reviewed to ensure that the East Lancashire Hospital's National Health Service (NHS) Trust Policy on consent to treatment and Department of Health (DoH) guidelines were being followed when seeking consent for cataract surgery. A set of 22 criteria derived as standards were formulated from the reference guide published by the DoH and from the East Lancashire trust policy document for consent to treatment. Each consent form was measured against these standards. Cases were randomly selected between BRI and BGH prospectively. All consent forms completed by physicians involved in formulating the standards were excluded. The review showed the NHS Trust Policy and DoH guidelines were largely followed when seeking consent for cataract surgery. However, certain areas were found to be deficient. If a health professional fails to obtain proper consent and the patient suffers harm as a result of treatment, it may be a factor in a claim of negligence against that health professional. Subsequent recommendations may include simple solutions that can be implemented to improve clinical practice when obtaining informed consent.
Objective Neurocognitive impairment was found to be heritable in individuals with schizophrenia and their relatives. However, the heritability of neurocognitive measures in families with and without schizophrenia has not been directly compared. In this study, we examined the genetic structure of clinical and neurocognitive measures in sibling pairs with and without schizophrenia to test the hypothesis that the familial aggregation of such measures may be altered by having schizophrenia. Method A total of 278 subjects including patients with schizophrenia and their non-psychotic full siblings, healthy controls, and their full siblings were recruited. Heritability was estimated for working memory, episodic memory, executive function and attention, as well as clinical features, such as positive, negative and disorganization symptoms. Results Many clinical and cognitive domains were impaired in subjects with schizophrenia and their non psychotic siblings. Negative symptoms, working memory, episodic memory and executive function, but not positive, disorganization symptoms and attention, were found to be significantly heritable in all sibling pairs. However, the heritability of working memory function was significantly (χ 2 (d.f.=6) =13.9, p =.031) decreased in proband sibling pairs (h2 =.38) as compared to control sibling pairs (h2 =.95). Significant genetic correlations were observed between negative symptoms and the cluster of working memory, episodic memory and executive function. Conclusions Several neurocognitive measures were heritable in sibling pairs with and without schizophrenia. However, schizophrenia reduced the heritability of working memory, perhaps due to disease-related environmental or genetic factors. Evidence for potential pleiotropy will inform future phenotypic studies.
A two-dimensional sample array synthesis has been used to screen carbon-coated Li(1−x)Mg x/2FePO4 and LiFe(1−y)Mg y PO4 powders as potential positive electrode materials in lithium ion batteries with respect to x, y and carbon content. The synthesis route, using sucrose as a carbon source as well as a viscosity-enhancing additive, allowed introduction of the Mg dopant from solution into the sol–gel pyrolysis precursor. High-throughput XRD and cyclic voltammetry confirmed the formation of the olivine phase and percolation of the electronic conduction path at sucrose to phosphate ratios between 0.15 and 0.20. Measurements of the charge passed per discharge cycle showed that the capacity deteriorated on increasing magnesium in Li(1−x)Mg x/2FePO4, but improved with increasing magnesium in LiFe(1−y) Mg y PO4, especially at high scan rates. Rietveld-refined XRD results on samples of LiFe(1−y)Mg y PO4 prepared by a solid-state route showed a single phase up to y =0.1 according to progressive increases in unit cell volume with increases in y. Carbon-free samples of the same materials showed conductivity increases from 10−10 to 10−8 Scm−1 and a decrease of activation energy from 0.62 to 0.51eV. Galvanostatic cycling showed near theoretical capacity for y =0.1 compared with only 80% capacity for undoped material under the same conditions.
Li-O2 batteries are considered as one of the future candidates for electrochemical power sources due to their high theoretical energy density. As the dominating component affects the performance of Li-O2 batteries, O2-cathode catalyst with high efficiency, low price, facile preparation is important. Herein, polyhedral and porous Mn2O3 rods are fabricated for cathode catalysts in Li-O2 batteries via electrospinning method followed by calcination. The Mn2O3 catalyst possesses a three-dimensional porous structure, which can offer good catalytic activity, expose plenty of active sites and improve the diffusion of electrolyte and O2. When employed as the cathode catalyst, the Li-O2 batteries show enhanced initial discharge capacity of 9701 mA h g−1 at a current density of 200 mA g−1, superior rate capacity and good cycling stability within 160 cycles at the capacity of 500 mA h g−1. These enhanced performances demonstrate a facile method to fabricate Mn2O3 with unique structure as a promising catalytic material for Li-O2 batteries.
EDAX measurement reveals that the atomic ratio of Ti/(Ti + Co) is much higher than the mole feed ratios in the preparation for the LiCo0.99Ti0.01O2 material. XPS observation further tells that in LiCo0.998Ti0.002O2 phase with quite low Ti amount, almost no Ti can enter into the LiCoO2 lattice, it is more inclined to enrich in the particle surface. Electrochemical examinations show that the cycling stability of LiCo0.998Ti0.002O2 is as good as that of LiCoO2/LiCo0.99Ti0.01O2 composite between 3.0 and 4.3 V, and the latter has a better rate performance. It is considered that the difference of the high rate performance between the Ti-modified LiCoO2 materials is more likely to originate from the different particle characteristics, when their Ti amounts are low enough.
This paper presents a framework that helps researchers to design and validate both formative and reflective measurement models. The framework draws from the existing literature and includes both theoretical and empirical considerations. Two important examples, one from international business and one from marketing, illustrate the use of the framework. Both examples concern constructs that are fundamental to theory-building in these disciplines, and constructs that most scholars measure reflectively. In contrast, applying the framework suggests that a formative measurement model may be more appropriate. These results reinforce the need for all researchers to justify, both theoretically and empirically, their choice of measurement model. Use of an incorrect measurement model undermines the content validity of constructs, misrepresents the structural relationships between them, and ultimately lowers the usefulness of management theories for business researchers and practitioners. The main contribution of this paper is to question the unthinking assumption of reflective measurement seen in much of the business literature.
For a CPV system, prediction of focal flux distribution at the receiver area will give insight to more effective, energy efficient designs and to estimate power output. An experimental method for in-situ prediction of heat flux distribution profile using inverse heat transfer technique on a flat plate receiver for a CPV square parabolic dish is presented. An IR camera is used to measure the temperature of the concentrated receiver surface. The receiver domain is discretised into several heat flux elements and heat flux values for each grid is then estimated using the measured infrared (IR) pixel temperature and ordinary least square. A 3-D steady state heat conduction equation with convection and radiation heat loss boundary is regarded as the forward problem. The simulated temperatures generated from the solution of forward problem using the predicted heat flux distribution and measured temperature distribution are in close agreement. For validation purpose, the concentrated heat flux is also measured using Gardon and Schmidt-Boelter heat flux sensor. The peak predicted focal heat flux on the receiver is found to be 37.41 kW/m2 whereas the heat flux value measured by the flux sensor is 39.15 kW/m2 within the deviation of 4.4%.
Acidic methanol solutions have been investigated for use in direct methanol microchannel fuel cells. The increased proton conductivity of a methanol solution containing sulfuric acid enables the anode to be constructed with the catalyst separated from the proton exchange membrane. This approach could be especially useful in the fabrication of thin-film microchannel fuel cells where a more complex carbon fabric electrode is not possible. The performance of sequential build-up fuel cells was shown to be improved by depositing an additional layer of Pt/Ru on the side-walls of the anode microchannels opposite the membrane. Results from anode half-cell and full cell experiments are reported.
Free-standing graphene paper with a grey metallic luster has been fabricated for the first time, by a convenient one-step method on a large scale. Herein, the assembly of graphene oxide dispersion into ordered paper occurs simultaneously with the chemical reduction of graphene oxide to graphene. The graphene paper presents the advantages of good flexibility, low weight (0.2 g cm−3) and high electrical conductivity (15 Ω sq−1). Moreover, the size and shape of the graphene paper are freely exchanged for those of the Teflon substrate used. The flexible graphene–PANI paper subsequently exhibits excellent supercapacitor performance with an enhanced specific capacitance (763 F g−1) and good cycling stability by electropolymerization of PANI nanorods on the above graphene paper. The method presented here shows great promise for the development of low-cost electrode materials in potential energy storage devices.
The reaction of natural pyrite and lithium was investigated in solvent-free, polymer electrolytes at medium temperature (90°C). In such a system the full capacity of pyrite is accessed in the first discharge–charge cycle, however, the system is affected by a substantial capacity fading especially in low rate discharges. The capacity fading observed is attributed to the irreversible reaction of the sulfur formed at the end of charge step and the polymer in the electrolyte. The investigation showed that the irreversible process occurring at 1.3V is not the cause of the capacity fading but it is resulting from the reduction of the above mentioned oxidation products.
Layered Li[Li0.12Ni z Mg0.32−z Mn0.56]O2 oxide cathodes containing lithium atoms in the transition metal layers were synthesized and characterized using X-ray diffraction (XRD), galvanostatic cycling, and differential scanning calorimetry (DSC). The Li[Li0.12Ni z Mg0.32−z Mn0.56]O2 cathodes deliver a specific discharge capacity of about 190mAh/g at room temperature and 236mAh/g at 55°C when cycled between 2.7 and 4.6V versus Li/Li+. Excellent capacity retention and smooth potential profiles at room and elevated temperatures over extended cycles suggest that this material does not convert into a spinel structure.