batterydata/paper-abstracts huggingface dataset:
Lithium difluoromono(oxalato)borate (LiODFB) has been used as a novel lithium salt for battery in recent studies. In this study, a series of novel electrolytes has been prepared by adding 30 vol% dimethyl sulfite (DMS) or dimethyl carbonate (DMC) as co-solvent into an ethylene carbonate (EC)/ethyl methyl carbonate (EMC) + LiX mixture, in which the LiX could be LiClO4, LiODFB, LiBOB, LiTFSI, or LiCF3SO3. These ternary electrolytes have been investigated for use in lithium ion batteries. FT-IR spectroscopy analysis shows that characteristic functional groups (–CO3, –SO3) undergo red-shift or blue-shift with the addition of different lithium salts. The LiODFB–EC/EMC/DMS electrolyte exhibits high ionic conductivity, which is mainly because of the low melting point of DMS, and LiODFB possessing high solubility. The Li/MCMB cells containing this novel electrolyte exhibit high capacities, good cycling performance, and excellent rate performance. These performances are probably because both LiODFB and DMS can assist in the formation of SEI films by reductive decomposition. Additionally, the discharge capacity of Li/LiCoO2 half cell containing LiODFB–EC/EMC/DMS electrolyte is 130.9 mAh g−1 after 50 cycles, and it is very comparable with the standard-commercial electrolyte. The results show that this study produces a promising electrolyte candidate for lithium ion batteries.
Here we report the oxygen reduction reaction (ORR) activity of Ag nanoparticles supported on boron doped multi-walled carbon nanotubes (Ag/B-MWCNTs) with different Ag loadings synthesized by a facile chemical method. Transmission electron microscopy (TEM) and X-ray diffraction patterns (XRD) measurements were employed to investigate the morphology and crystal structure of the as-prepared catalysts. The electrochemical results demonstrated that all the Ag/B-MWCNTs samples catalyzed the ORR in alkaline media by an efficient four-electron pathway. Furthermore, Ag/B-MWCNTs with lowest Ag loading (20%) performed the highest mass activity towards ORR mainly due to the synergistic effect of Ag nanoparticles and B-MWCNTs. This work brings insight into the role of supporting materials in reducing the loading of metal catalyst towards low-cost ORR in alkaline media.
Mobile systems, such as smartphones, are becoming the primary platform of choice for a user’s computational needs. However, mobile devices still suffer from limited resources such as battery life and processor performance. To address these limitations, a popular approach used in mobile cloud computing is computation offloading, where resource-intensive mobile components are offloaded to more resourceful cloud servers. Prior studies in this area have focused on a form of offloading where only a single server is considered as the offloading site. Because there is now an environment where mobile devices can access multiple cloud providers, it is possible for mobiles to save more energy by offloading energy-intensive components to multiple cloud servers. The method proposed in this paper differentiates the data- and computation-intensive components of an application and performs a multisite offloading in a data and process-centric manner. In this paper, we present a novel model to describe the energy consumption of a multisite application execution and use a discrete time Markov chain (DTMC) to model fading wireless mobile channels. We adopt a Markov decision process (MDP) framework to formulate the multisite partitioning problem as a delay-constrained, least-cost shortest path problem on a state transition graph. Our proposed Energy-efficient Multisite Offloading Policy (EMOP) algorithm, built on a value iteration algorithm (VIA), finds the efficient solution to the multisite partitioning problem. Numerical simulations show that our algorithm considers the different capabilities of sites to distribute appropriate components such that there is a lower energy cost for data transfer from the mobile to the cloud. A multisite offloading execution using our proposed EMOP algorithm achieved a greater reduction on the energy consumption of mobiles when compared to a single site offloading execution.
Charcot neuroarthropathy is a significant limb-threatening complication that develops in some patients with long-term diabetes mellitus. Early diagnosis is vital to secondary prevention of the destructive process and avoidance of consequent deformity and, ultimately, amputation. The purpose of this study was to determine which historical and physical findings would be more accurate risk factor indicators in those diabetics with and without Charcot foot deformity. A controlled series of tests, historical findings, and physical examinations were performed on 41 patients with diabetes who were Charcot-free and 18 patients with diabetes with known chronic CD of the foot by using inexpensive hand-held instruments in a clinical setting. Physical examination included evaluation of vascular and neurologic characteristics. Historical findings consisted of those normally elicited from systems review or past medical history. The results indicate that simple neurologic testing combined with a thorough patient history were the most beneficial tools to determine diabetics with a higher probability of developing CD. Specifically, history of retinopathy (P < .02), nephropathy (P < .003), and previous foot ulcer (P < .01) were found to be predictive. The neurologic findings of vibratory sensation (P < .001), deep tendon reflexes (P < .05), and the 5.07 (10 g) Semmes-Weinstein monofilament test (P < .001) were also highly correlative for the development of Charcot foot deformity. Vascular examinations were found to differentiate poorly between groups. The application of this data may provide for earlier detection of Charcot arthropathy based on the predictive capabilities.
The lithium battery using Fe3O4 fine particles has been constructed. The discharge characteristics were improved by the addition of India ink or polyvinyl alcohol (PVA). The discharge potential at 60°C maintained 2.5V versus Li/Li+ up to 500mAhg−1 and was 1.8V at a large capacity of 926mAhg−1. The possibility of secondary battery was discussed from the result of cycling test with 926mAhg−1. Similar potential curve was obtained in the second cycle. Although degradation was observed in the third cycle, cyclability was maintained. However, the test cell stopped in fourth discharge. It is concluded that a large capacity was achieved at 60°C using fine particles of Fe3O4 with PVA additive. According to the cycling test, it is expected to be a secondary battery by further development in nanostructure of the cathode.
The electrode material based on the carbonization of Fe cations adsorbed onto polyaniline (PANI) (C-Fe/PANI) was directly synthesized on nickel foam by pyrolysis of the iron-PANI mixture coated on nickel foam in a tube furnace under the N2 atmosphere. The characterization of the as-synthesized electrode materials was carried out using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) equipped with a scanning transmission electron microscopy along with energy dispersive X-ray (STEM-EDX) and X-ray photoelectron spectroscopy (XPS). The electrochemical behavior of the working electrode was analyzed in both positive and negative potential window in a three-electrode cell configuration using 6 M KOH electrolyte, and thereafter, a C-Fe/PANI symmetric device was successfully fabricated. The C-Fe/PANI symmetric device was found to perform at a high applied potential difference of 1.65 V in 6 M KOH. At a current density of 0.5 A g−1, this device exhibited energy and power densities of 41.3 W h kg−1 and 231.9 W kg−1 respectively. Additionally, the device exhibited a maximum power of 469.4 kW kg−1. The device further showed excellent cycling stability with 100% Columbic efficiency and capacity retention of 72% at a current density of 5 A g−1 over 10 000 galvanostatic charge-discharge cycles.
A quasi-static mechanical abuse test program on cylindrical Lithium ion battery cells has been performed at a state of charge (SoC) of 0%. The investigated load cases involved radial crushing, local lateral indentation and global three-point bending of the cell. During the tests, the punch load, the punch displacement, the cell voltage and the temperature development of the cell have been monitored using an infrared camera and temperature sensors. After the test, the cells have been analysed using computer tomography. It is indicated that macroscopic jelly roll fracture on a global scale initiates the internal short circuits, revealed by a sudden decrease of the global mechanical load due to the rupture, followed by a drop of the measured voltage and immediate increase in cell temperature. A macro-mechanical finite element crash simulation model has been established for the cell housing and the jelly roll. The classical stress-based criterion after Mohr and Coulomb (MC) has been applied to predict fracture and the initiation of an internal short circuit of the jelly roll. The MC criterion correctly represents the punch displacement to fracture, where the predicted fracture locations correspond to the observed locations of the internal short circuits of the cells.
We have successfully synthesized NixSnyOz nanostructured composites consisting of Sn, SnO, Ni3Sn, and Ni3Sn2 phases via galvanic replacement reaction between Ni2+ and Sn at high temperature in triethylene glycol medium. The composites are used as novel anode materials for lithium-ion batteries. At different reaction times, the as-prepared composites show hollow structures with different compositions and particle sizes, as analyzed by X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. For example, the NixSnyOz-6h composite electrode with a small particle size (<60 nm) exhibits highly stable specific capacities of 615 and 555 mAh g−1 at current densities of 100 and 1000 mA g−1 after 100 cycles, respectively, and a high rate performance with a high reversible capacity of 377 mAh g−1 at a current density of 3000 mA g−1. The excellent electrochemical performance can be attributed to the large contact area between the electrolyte and the material as well as to the mixed inactive phases of Ni and Li2O combining with the hollow structures, which could act as an electron conductor and an effective buffer against volume changes during cycling and could inhibit the agglomeration of active particles (Sn), resulting in a stable-structure active material and accelerated kinetics of the reaction.
One of the main challenges in the development of lithium-sulphur batteries is the so called “shuttle mechanism”, which involves the diffusion of sulphur and polysulphides from the sulphur electrode to the lithium electrode, where they get reduced via chemical reactions with lithium. The shuttle mechanism decreases the capacity delivered by the battery, hampers its rechargeability, and promotes battery self-discharge. We have developed a simple model of the shuttle mechanism that reproduces quantitatively the rate of the initial self discharge of lithium-sulphur batteries. The rate of sulphur and polysulphide diffusion has been quantified by studying cells with varying number of separators between the electrodes. We have found that it is essential that the model incorporates the presence of carbon additive in the sulphur electrode, which slows down the decrease of the open circuit potential with time. The model also reproduces well the rate of self-discharge of lithium-sulphur cells containing sulphur dissolved in the electrolyte. In conclusion, the present model provides a basic understanding of the mechanism of self-discharge of lithium-sulphur cells, and allows quantifying the two main causes of sulphur loss at the sulphur electrode: sulphur diffusion across a concentration gradient and sulphur reaction with polysulphides formed at the lithium electrode.
A commercial coal tar pitch was thermally treated at 430°C for 4h and then submitted to hot filtration in order to separate the isotropic phase from the mesophase developed during the treatment. Each phase was then oxidatively stabilized in order to preserve its structure during carbonization and then carbonized at temperatures ranging from 700 to 1000°C. The effect of the microstructure, particle morphology and chemical composition of the carbons and also the influence of their carbonization temperature on the electrochemical behaviour as electrode materials in lithium cells were studied. Galvanostatic cycling of lithium test cells using the carbon materials as positive electrodes showed the improvement of the electrochemical performance in both isotropic and anisotropic phases by stabilization with air previous to carbonization. More subtle differences between isotropic and anisotropic samples were evidenced and interpreted in terms of their textural properties. Moreover, the electrochemical impedance spectroscopy (EIS) has been demonstrated to be an interesting technique to elucidate the changes occurred in the electrode interfaces when these coal tar pitch based carbons are cycled.
In this work the synthesis of a nickel doped cubic manganese spinel has been studied for application as cathode material in secondary lithium batteries. Six different experimental approaches have been tested in order to carry out a screening of the various possible synthetic routes. The used synthetic strategies were wet chemistry (WC), solid state (SS), combustion synthesis (CS), cellulose-based sol–gel synthesis (SG-C), ascorbic acid-based sol–gel synthesis (SG-AA) and resorcinol/formaldehyde-based sol–gel synthesis (SG-RF). The goal of our study is to obtain insights about how the synthesis conditions can be modified in order to achieve a material with improved electrochemical performances in such devices, especially in high current operating regimes. The synthesized materials have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), atomic absorption, inductively coupled plasma (ICP-MS) atomic emission spectroscopy, surface area measurements and tested as high voltage cathodes in Li-ion electrochemical devices.
We report the neuropsychological and MRI investigation of a patient (GP) who developed a selective impairment of spatial short-term memory (STM) following damage to the dorso-mesial areas of the right frontal lobe. We assessed in this patient spatial STM with an experimental procedure that evaluated immediate and 5–20 s delayed recall of verbal, visual and spatial stimuli. The patient scored significantly worse than normal controls on tests that required delayed recall of spatial data. This could not be ascribed to a deficit of spatial episodic long-term memory because amnesic patients performed normally on these tests. Conversely, the patient scored in the normal range on tests of immediate recall of verbal, visual and spatial data and tests of delayed recall of verbal and visual data. Comparison with a previously described patient who had a selective deficit in immediate spatial recall and an ischemic lesion that affected frontal and parietal dorso-mesial areas in the right hemisphere (Carlesimo GA, Perri R, Turriziani P, Tomaiuolo F, Caltagirone C. Remembering what but not where: independence of spatial and visual working memory in the human brain. Cortex. 2001 Sep; 37(4):519–34) suggests that the right parietal areas are involved in the short-term storage of spatial information and that the dorso-mesial regions of the right frontal underlie mechanisms for the delayed maintenance of the same data.
Abstract Energy security and climate change are long-term challenges for the transportation sector in the United States. Natural gas use in vehicles may reduce the dependence of the transportation sector on petroleum fuels, but provides only a marginal reduction in well-to-wheels (WTW) greenhouse gas (GHG) emissions. Improvement in vehicle efficiency provides a proportional reduction in both petroleum use and GHG emissions. The use of conventional hybrid electric vehicles reduces WTW petroleum use and GHG emissions by 33% compared to gasoline internal combustion engine vehicles (ICEVs). Using fossil fuels-derived natural gas for electricity and hydrogen production reduces WTW GHG emissions of battery electric vehicles and fuel cell electric vehicles by 56% and 39%, respectively, compared to gasoline ICEVs. Reductions in GHG emissions in excess of 80% compared to conventional gasoline ICEVs can be achieved with the use of renewable sources, such as wind, solar, and biomass, as energy feedstocks for electricity and hydrogen production.
Cognitive inhibition is a key mechanism in the regulation of emotion. There is emerging evidence that depression is characterized by deficits in the inhibition of mood-congruent material. These deficits could result in prolonged processing of negative, goal-irrelevant aspects of presented information thereby hindering recovery from negative mood and leading to the sustained negative affect that characterizes depressive episodes. Indeed, it has been suggested that deficits in cognitive inhibition lie at the heart of memory and attention biases in depression, and set the stage for ruminative responses to negative events and negative mood states. A ruminative response style results in a heightened vulnerability to experience episodes of major depression. Recent research has demonstrated that deficient inhibition of negative material is associated with heightened rumination. In this article, we review the depression literature with a focus on studies that investigate cognitive inhibition in depressed participants and in participants who report a history of major depressive episodes. In addition, we summarize neurobiological findings that indicate a strong relation between depression and deficits in inhibition and we take a closer look at the relation of inhibition, rumination and mood regulation.
Epileptogenesis, i.e. the process leading to epilepsy with spontaneous recurrent seizures, can be initiated by a number of brain damaging insults, including traumatic brain injury, status epilepticus (SE), and stroke. Such acquired epilepsy is often associated with memory impairment and behavioral problems. There has been a growing interest in the use of antiepileptic drugs (AEDs) for neuroprotection and prevention or modification of epileptogenesis induced by such brain insults. One promising candidate in this respect is valproic acid (VPA), a widely used AED that has been reported to exert neuroprotective activity in a number of in vitro and in vivo models. The present study investigated whether VPA reduces brain damage and improves functional outcome in a rat model of post-SE epilepsy. A self-sustaining SE was induced by prolonged electrical stimulation of the basal amygdala via a depth electrode. SE was terminated after 4h by diazepam, immediately followed by onset of treatment with VPA. VPA was injected i.p. at a bolus dose of 400mg/kg, followed by three times daily administration of 200mg/kg for 4weeks. A control group received vehicle instead of VPA after SE. Spontaneous seizures were recorded in all rats of both groups following termination of treatment, without significant inter-group difference in seizure frequency or severity. However, treatment with VPA after SE prevented the hyperexcitability and locomotor hyperactivity observed in vehicle-treated epileptic rats. Furthermore, VPA completely counteracted the neuronal damage in the hippocampal formation, including the dentate hilus. The data demonstrate that, although VPA does not prevent the occurrence of spontaneous seizures after SE, it exerts powerful neuroprotective effects and prevents part of the behavioral alterations, demonstrating that administration of VPA immediately after SE exerts a favorable effect on long-term functional outcome.
The significance in electrochemistry of the term ‘polarization’ is carefully explained. Several diverse effects contribute to the overall polarization and the magnitudes of the corresponding overvoltages may be calculated via equations that are presented. An informative graphical method of presenting data on the evolution of the individual overvoltages during voltammetry is described and exemplified. The diagram may be constructed from experimental data or as part of a predictive exercise using either digital simulation or convolutive modelling. Four examples of these polarization inventory diagrams are presented. Among the features that may be factored into the diagrams are various voltammetric protocols, electrode reactions of any degree of reversibility, arbitrary transfer coefficient, diffusion coefficient diversity, varied cell geometries, transport by diffusion and/or migration, first-order homogeneous reactions, uncompensated resistance, and multi-layered electrolyte solutions.
The influence of the change of Fermi level electrons position of activated carbon μ C caused by chemical modification of its porous surface by Mn2+ ions on its capacitive characteristics in 7.6m KOH, 4m KI, 2m ZnI2 aqueous solutions is investigated in this work. The detection of adsorbed Mn2+ ions on the surface of activated carbon was carried out according to methods of secondary ionic mass spectrometry (SIMS). An increase in electronic density on the Fermi level of modified with Mn2+ activated carbon was determined with a help of X-ray photoelectron spectroscopy (XPS) data. Capacitive characteristics of the electrodes have been investigated by means of electrochemical impedance spectroscopy, computer modeling, and galvanic discharge. The correlation between electronic structure of modified activated carbon (MAC) and thermodynamic characteristics of ions of the used electrolytes is established. On the basic of the obtained experimental data, electrochemical system of the hybrid capacitor with a specific capacitance of 1740Fg−1 and with a specific energy of 30mWhg−1 is developed.
This paper proposes optimum green energy systems for electricity generation of island resorts in Malaysia. A combination of solar energy and wind energy as intermittent renewable energy sources with a fuel cell (FC) system and a battery storage energy system as a backup to the green energy system is introduced for this study. This system is eco-friendly, economical over the long-term, highly sustainable and reliable. In addition, a diesel-based energy system as a non-green system is compared with the proposed green system. National Renewable Energy Laboratory's (NREL) HOMER software is used to determine and compare the optimal configuration green energy system with the diesel-based energy system in terms of net present cost, sensitivity analysis and pollutant gas emission. The feasibility and assessment of the proposed system is evaluated by utilizing the load profile and considering the geographical condition of a village (Juara village in Tioman Island) with approximately 30 chalets located in southern Malaysia. HOMER uses two types of load profiles for each given year. The first load profile is used during the presence of tourists, and the second profile is used when the locals are the main inhabitants of the island. The optimization management for the green energy system is performed through unit sizing to find the optimum power management analysis and to perform cost analysis of the system. The potential of renewable energy as well as a diesel-based energy system to meet the power demand for such a stand-alone system is considered. Technically feasible and economically viable green energy systems as prospective plans are explored in this study.