batterydata/paper-abstracts huggingface dataset:
Despite the intense concentration on lithium-based batteries, safety, ease of construction and cost continue to drive the search for alternatives that do not suffer from such restrictions. We present here preliminary work on the development of thin film Mg2+ conducting electrolytes as the key starting point for the development of all-solid-state Mg batteries. Initial studies explored compositions in the Mg0.5CexZr2-x(PO4)3 (x = 0.1, 0.2 and 0.3) system first as pellets and with somewhat optimized compositions (with x = 0.2) as thin films. Introduction of Ce allows sintering to full density at temperatures where Ce free films do not densify completely. The work reported here relies on the synthesis of nanopowders (NPs) using liquid-feed flame spray pyrolysis that offers the potential to reduce processing conditions, to control final average grain sizes (AGSs) and provide single-phase materials with good to excellent mechanical properties. The pellets and then thin (≤50 μm) films produced here show conductivities of up to 3 × 10−3 mS cm-1 at ≈ 300 °C, which if extrapolated (using an Ea of ≈30) to 400 °C would be close to 10−2 mS cm−1 in keeping with the best reported values in the literature. The thin films reported here offer nearly full densities beyond what is currently achievable by any other method. The ionic area specific resistance (IASR) values for these thin films were found to be 1400 Ω cm2 at 300 °C and are estimated to drop to 110 Ω cm2 at 400 °C, significantly lower than values for pellets reported elsewhere.
The response of Li-ion cells to mechanically induced internal electrical shorts is an important safety performance metric design. We assume that the battery internal configuration at the onset of electrical short influences the subsequent response and can be used to gauge the safety risk. We subjected a series of prismatic Li-ion cells to lateral pinching using 0.25″, 0.5″, 1″, 2″ and 3″ diameter steel balls until the onset of internal short. The external aluminum enclosure froze the internal cell configuration at the onset of short and enabled us to cross-section the cells, and take the cross-section images. The images indicate that an internal electric short is preceded by extensive strain partitioning in the cells, fracturing and tearing of the current collectors, and cracking and slipping of the electrode layers with multiple fault lines across multiple layers. These observations are at odds with a common notion of homogeneous deformation across the layers and strain hardening of electrodes that eventually punch through the separator and short the cell. The faults are akin to tectonic movements of multiple layers that are characteristic of granular materials and bonded aggregates. The short circuits occur after extensive internal faulting, which implies significant stretching and tearing of separators.
Thermal energy storage (TES) and batteries have recently become increasingly important for peak-load shifting in energy systems. However, optimizing energy systems is difficult because each machine has multiple combinations of operations, and the objective function contains transformed nonlinear or non-convex characteristics. Therefore, we adopted the epsilon-constrained differential evolution (ɛDE) in order to minimize operating costs. We demonstrate that the ɛDE method efficiently solved strict constraint optimization problems on three energy systems: a self-consumption model (Case 1), total amount of a purchased model (Case 2), and a full connection model (Case 3) under 126 case studies. Although 216 decision variables were used under the nonlinear condition, we were able to obtain the optimal solution within a short time period, 16min on an ordinary PC. Moreover, we proposed a new index “Area rate of prices (ARP)” in order to evaluate the effects of purchased and sold electricity prices on the operating costs. The results showed that when the area rates of purchased price to sold price are higher than 0.2 (ARP>0.2), Case 1 was superior to Case 2. On the other hand, when the ARP value was less than 0.2, Case 2 was superior to Case 1. Therefore, we can conduct the optimization on everyday practical situations because ɛDE requires low computational cost. Even if the operators cannot conduct the optimization in practical energy management, they can easily determine the operation strategy by calculation of the ARP value. Therefore, the ɛDE and ARP methods have substantial advantages for energy system optimization.
Our study explored the size-dependent collection characteristics for micron-sized particles using several kinds of commercially available woven nylon net filters. The particle concentrations with and without the filter were compared to determine the filtration characteristics. The theoretical efficiencies based on a single-fiber theory and a hole model were also computed. Although the theoretical efficiencies were generally consistent with the experimental results, the non-uniformity of air velocity profile within a mesh hole, and a particle's detachment from or bounce off the filters, should be further investigated in future research. Overall, the present study revealed the size-fractionation capability of the nylon wire mesh filters for micron-sized particles from experimental and theoretical points of view. Unlike impactors, the size-fractionation characteristics of the nylon wire mesh filter were determined by particle size, mesh fiber diameter, and a combination of different particle collection mechanisms including impaction, interception, and gravitational settling. Each mechanical process appears interdependently governed in part by the filter dimensions such as filter mesh size (diameter of opening) as well as related variables such as packing density and fiber diameter.
This article reports a case study of the application of FMECA and FTA methods to inform the design of effective maintenance program for a waste heat recovery power plant in the hot arid climate of the United Arab Emirates. It illustrates the strengths and weaknesses of these approaches through a case study report of a live plant in a cement factory. The article highlights the implications and importance of plant-specific contextual factors in conducting quality FMECA and FTA.
As an alternative to acute hospitalisations, all communities in Norway are required to provide inpatient care in municipal acute bed units (MAUs) for patients who can be treated at the primary care level. Patient selection is challenging, and some patients need transfer from MAUs to hospitals. The aim of this study was to examine associations between characteristics of the patient at admission to MAU and further transfer to hospital.
Electrolyte flow rate is a key factor that affects the performance of vanadium redox flow battery (VRFB). A kilo-watt class VRFB system is fabricated to investigate the effects of electrolyte flow rate on the performance of VRFB. The experiments show that the capacity increases, but the system efficiency decreases with the increase of electrolyte flow rate. An optimal strategy of electrolyte flow rate is proposed to improve the system efficiency and keep the high capacity simultaneously, which is corresponding to optimize the electrolyte flow rate at different stages of charge and discharge processes. The results show that the system efficiency can be improved as high as 8% when keeping high capacity simultaneously.
Mild cognitive impairment (MCI) is a critical pre-dementia target for preventive interventions. There are few brief screening tools based on self-reported personal lifestyle and health-related information for predicting MCI that have been validated for their generalizability and utility in primary care and community settings.
The role of the tobacco-alkaloid nicotine in tumour biology is widely discussed in the literature. Due to a strong capacity to induce angiogenesis, a pro-mutagenic potential in non-tumour and cancer cells, and a pro- and anti-apoptotic influence, nicotine seems to promote the growth of established tumours. However, results indicating DNA damage and genetic instability associated with nicotine have been contradictory thus far. A variety of markers and endpoints of genotoxicity are required to characterize the genotoxic potential of nicotine. Induction of DNA single- and double-strand breaks, the formation of micronuclei, and the induction of sister chromatid exchange and chromosome aberrations represent possible genotoxicological endpoints at different cellular levels. Human lymphocytes were exposed to nicotine concentrations between 1μM and 1mM for 24h in vitro. The comet assay, the cytokinesis-block micronucleus test, the chromosome aberration (CA) test, and the sister chromatid exchange (SCE) test were then applied. Viability and apoptosis were measured by flow cytometry in combination with the annexin V-propidium iodide staining test. In this test setting, no enhanced DNA migration was measured by the comet assay. An increase in the micronucleus frequency was detected at a concentration of 100μM nicotine without affecting the frequency of apoptotic cells. A distinct genotoxic effect was determined by the CA test and the SCE test, with a significant increase in CA and SCE at a concentration of 1μM. In the annexin V test, nicotine did not influence the proportion of apoptotic or necrotic cells. The current data indicating the induction of CA by nicotine underscore the necessity of ongoing investigations on the potential of nicotine to initiate mutagenesis and tumour promotion. Taking into account the physiological nicotine plasma levels in smokers or in nicotine-replacement therapy, particularly the long-term use of nicotine should be critically discussed.
The current study tested a path model that examined the association between early emotional experiences with peers and male body attitudes and whether general feelings of shame and body-focused shame mediate this relationship, while controlling for the effect of body mass index.
In order to estimate the effect of the dispersion of nano-carbon species into a composite electrode, ultrasonic pretreatments under various conditions have been carried out for two kinds of nano-carbons, vapor grown carbon fiber (VGCF) and acetylene black, before preparing a composite electrode with iron powder. The cyclic voltammetry behavior of the resulting Fe/nano-carbon composite electrodes is significantly influenced by the kind of nano-carbon and the pretreatment conditions in spite of as a low content of nano-carbon as 20wt.%. The largest redox current at initial cycle is obtained for Fe/VGCF composite electrode with the 30min pretreatment of VGCF in ethanol. The dispersion of nano-carbon verifies the apparent density of the composite, and then affects the feature of three-phase interface among the ion-conducting electrolyte, the redox reaction surface, and the electron conductor.
The electrodes mass ratio of MnO2/activated carbon supercapacitors has been varied in order to monitor its influence on the potential window of both electrodes and consequently to optimize the operating voltage. It appeared that the theoretical mass ratio (R =2), calculated considering an equivalent charge passed across both electrodes, is underestimated. It was demonstrated that R values of 2.5–3 are better adapted for this system; the extreme potential reached for each electrode is close to the stability limits of the electrolyte and active material, allowing a maximum voltage to be reached. During galvanostatic cycling up to 2V, the best performance was obtained with R =2.5. The specific capacitance increased from 100 to 113Fg−1 during the first 2000 cycles, then decayed up to 6000 cycles and finally stabilized at 100Fg−1. SEM images of the manganese based electrode after various numbers of thousands cycles exhibited dramatic morphological modifications. The later are suspected to be due to Mn(IV) oxidation and dissolution at high potential values. Hence, the evolution of specific capacitance during cycling of the asymmetric capacitor is ascribed to structural changes at the positive electrode.
Manns PJ, Tomczak CR, Jelani A, Cress ME, Haennel R. Use of the continuous scale physical functional performance test in stroke survivors. Objective To (1) determine the feasibility of the continuous scale physical functional performance 10-item test (CS-PFP10) for the measurement of physical function in stroke survivors, (2) characterize physical functional performance of stroke survivors and their matched controls, and (3) explore the associations among physical functional performance, ambulatory activity, and peak oxygen uptake (Vo 2peak). Design Case control. Setting University research setting. Participants Ten participants with stroke and 10 healthy controls matched for age, sex, and physical activity. Interventions Not applicable. Main Outcome Measures The CS-PFP10 test was used to measure functional ability. The test requires performance of 10 serial tasks that range from low to high difficulty. The step activity monitor was used to measure absolute ambulatory activity and was reported as the average number of steps a day over a 4-day period. Vo 2peak was determined using a metabolic cart and a recumbent cycle ergometer. Results Stroke survivors scored lower than healthy controls on all individual tasks, domains, and the total score on the CS-PFP10. Higher Vo 2peak was associated with higher total scores on the CS-PFP10 in both stroke survivors and controls. In stroke survivors, lower levels of impairment (as indicated by the Chedoke-McMaster stroke assessment) were associated with higher total CS-PFP10 scores. Conclusions The CS-PFP10 is a measure of physical performance that is feasible to use with ambulatory participants with stroke. Future investigations with people with stroke should explore the ability of the CS-PFP10 to provide meaningful information about change in CS-PFP10 subscales with interventions that target items on the subscales, such as balance or upper extremity strength.
A novel process has been demonstrated to recycle LiFePO4 from spent lithium-ion batteries. The spent LiFePO4 cathode materials were leached by phosphoric acid (H3PO4) solution and followed by subsequent heat treatment to obtain FePO4·2H2O hierarchical microflowers. Furthermore, new LiFePO4/C sample was prepared via a carbothermal reduction process of calcining the obtained FePO4·2H2O precursor with Li2CO3 and glucose in N2 atmosphere. The re-synthesized LiFePO4/C sample inherits the hierarchical microflower structure of the FePO4·2H2O precursor, with a diameter of 1–2μm. Electrochemical test indicates that the re-synthesized LiFePO4/C shows excellent electrochemical performance as cathode material for lithium ion batteries. The discharge capacity can reach 159.3mAhg−1 at 0.1C rate and 86.3mAhg−1 even at 20C rate, respectively. After 500 cycles at 5C, they still can deliver a discharge capacity of 105mAhg−1 with a high capacity retention rate of 95.4%. Moreover, the lithium element was also recovered in the form of LiH2PO4 from the filtrate after collecting the FePO4·2H2O precipitate. This work provides a promising route for large scale recovery and reuse of spent LiFePO4 cathode materials of lithium-ion batteries.
The thermal behavior of a large-format lithium ion cell has been investigated during measurements on cell and battery level. High current discharges up to 300 A are the main topic of this study. This paper demonstrates that the temperature response to high current loads provides the possibility to investigate internal cell parameters and their inhomogeneity. In order to identify thermal response caused by internal cell processes, the heat input due to contact resistances has been minimized. The differences between the thermal footprint of a cell during cell and battery measurements are being addressed. The study presented here focuses on the investigation of thermal hot and cold spots as well as temperature gradients in a 50 Ah pouch cell. Furthermore, it is demonstrated that the difference between charge and discharge can have significant influence on the thermal behavior of lithium ion cells. Moreover, the miscellaneous thermal characteristics of differently aged lithium ion cells highlight the possibility of an ex-situ non-destructive post-mortem-analysis, providing the possibility of a qualitative and quantitative characterization of inhomogeneous cell-aging. These investigations also generate excellent data for the validation and parameterization of electro-thermal cell models, predicting the distribution of temperature, current, potential, SOC and SOH inside large-format cells.
LiF is successful used to modify the surface of layered LiNi1/3Co1/3Mn1/3O2 via a wet chemical method followed by an annealing process. The lattice structure of LiNi1/3Co1/3Mn1/3O2 is not changed distinctly after modification and part of F− dopes into the surface lattice of the oxide. The LiF-modified oxide exhibits capacity retentions of 97.5% at 0.1 C at room temperature and 93.5% at 1 C at 60 °C after 50 cycles, and delivers a high discharge capacity of 137 mAh g−1 at 10 C at room temperature. Furthermore, it has reversible capacities of 124.4 mAh g−1 at 1 C at 0 °C and 85.6 mAh g−1 at 0.1 C at −20 °C, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests show that the LiF-modified layer can reduce the dissolution of metal ions in the electrode and enhance the conductivity of the oxide surface through partly F-substitution. LiF modification will be promising for the application of layered oxide for lithium ion batteries.
Cycling performance of Li-ion cells was studied by using electrochemical impedance spectroscopy (EIS). Results showed that total resistance (R cell) of the Li-ion cells is mainly composed of bulk resistance (R b), solid-state interface resistance (R sei) and charge-transfer resistance (R ct). During cycling, the R b and R sei remain unchanged while the R ct displays two minima in the same voltage regions where the major peaks of differential capacities are present. The R ct can be linked to kinetics of the cell electrochemical reaction. In response to the temperature change, the R b and R sei vary in a very similar manner, while the R ct shows significant difference. In the fully charged and discharged states as well as at the low temperatures (≤20°C), the R cell of the Li-ion cells is predominated by the R ct. Using the term of the R ct, we explained two low temperature phenomena of the Li-ion battery: (1) charging of a fully discharged cell is much more difficult than discharging of a fully charged cell, and (2) both the power (operating voltage) and energy (delivered capacity) are substantially reduced.
Deep brain stimulation (DBS) is a neurosurgical procedure that allows targeted circuit-based neuromodulation. DBS is a standard of care in Parkinson disease, essential tremor and dystonia, and is also under active investigation for other conditions linked to pathological circuitry, including major depressive disorder and Alzheimer disease. Modern DBS systems, borrowed from the cardiac field, consist of an intracranial electrode, an extension wire and a pulse generator, and have evolved slowly over the past two decades. Advances in engineering and imaging along with an improved understanding of brain disorders are poised to reshape how DBS is viewed and delivered to patients. Breakthroughs in electrode and battery designs, stimulation paradigms, closed-loop and on-demand stimulation, and sensing technologies are expected to enhance the efficacy and tolerability of DBS. In this Review, we provide a comprehensive overview of the technical development of DBS, from its origins to its future. Understanding the evolution of DBS technology helps put the currently available systems in perspective and allows us to predict the next major technological advances and hurdles in the field.
Supercapacitors and batteries have been intensively investigated but there is much confusion and misleading between them in publications. In particular, some battery behaviours are incorrectly as supercapacitors and some reported “remarkable” performances like the high specific capacitance of 2188 F g−1 for Ni(OH)2 nanospheres are not true. It is likely that the energy storage mechanism and the similar device configuration/characterization techniques cause confusions. It is important to clarify and remove confusion about both theoretical and experimental aspects of these two types of energy devices. This review starts with briefing fundamentals of battery and supercapacitor specifically emphasizing the essential difference on energy storage mechanism between pseudocapacitors and batteries, in which the former undergoes rapid surface-controlled electrochemical reactions without diffusion control and phase transformation, while the latter stores energy in the crystal lattices or porous materials through much slower electrochemical reactions with limits from the phase transformation, chemical binding changes or/and reactant diffusions. Correct characterization and analysis methods such as cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy with a suggested working flowchart to distinguish them are presented while offering thoughtful discussions and explanations about the confusions. Perspectives are also offered for realizing high-energy density ECs without trading off its high power density.
Thin film batteries with amorphous sulfide-based solid electrolytes were investigated. The interfacial resistance of the battery has been drastically reduced by inserting a very thin LiNbO3 layer between the LiCoO2 cathode and solid electrolyte. The cycle performance of the battery is affected by the composition of the Li2S–P2S5 solid electrolyte. From XPS analysis, it is suggested that the electrochemical stability of the solid electrolyte changes as the composition of the solid electrolyte changes. Thin film batteries have shown both high capacity and good cycle performance with a solid electrolyte of suitable composition and silicon thin layer at the anode interface. Finally, a capacity of 400μAhcm−2 at 500 cycles has been achieved with a 9.1μm-thick cathode.
Thermodynamic modelling of the Ca–Pb system was carried out. The thermodynamic parameters were determined using available experimental information: phase diagram data and thermodynamic quantities. For this system, the liquid phase was described from the association model with the “Ca2Pb” associated complex. The calculations well restore experimental values. All the results so-obtained (optimised thermodynamic parameters and calculated phase diagram) are reported in this paper and discussed.
The cyclic voltammograms (CVs) and current-time curves of methanol electro-oxidation, assisted by K2FeO4, decomposed K2FeO4 and Fe(NO3)3 added in strong alkaline solution, were investigated on a Pt electrode. The results show that Fe(NO3)3 and K2FeO4, especially decomposed K2FeO4, can promote the activity and poisoning tolerance of a Pt electrocatalyst for methanol oxidation in alkaline solution. We propose that iron(III)-containing compounds such as Fe(OH)3 and FeOOH in a strong alkaline solution tend to encourage the formation of OH adsorption (OHads) species, which are necessary for the promotion of the CO-like intermediates of oxidation on the Pt electrode.