batterydata/paper-abstracts huggingface dataset:
This paper describes a fault diagnosis system for automotive generators using discrete wavelet transform (DWT) and an artificial neural network. Conventional fault indications of automotive generators generally use an indicator to inform the driver when the charging system is malfunction. But this charge indicator tells only if the generator is normal or in a fault condition. In the present study, an automotive generator fault diagnosis system is developed and proposed for fault classification of different fault conditions. The proposed system consists of feature extraction using discrete wavelet analysis to reduce complexity of the feature vectors together with classification using the artificial neural network technique. In the output signal classification, both the back-propagation neural network (BPNN) and generalized regression neural network (GRNN) are used to classify and compare the synthetic fault types in an experimental engine platform. The experimental results indicate that the proposed fault diagnosis is effective and can be used for automotive generators of various engine operating conditions.
Experimental data elucidating the time-dependent composition of the electrolyte within a standard lithium-sulfur battery cell are presented. The electrolyte employed consisted of a solution of LiTFSI in a 1:1 mixture of dimethoxyethane and dioxolane, including nitrate salts. In order to track the decomposition reactions of the electrolyte components, the cells were run for a fixed number of cycles, after which they were opened and the remaining electrolyte was extracted with an excess amount of 1,4-dioxane. The amount of each of the components (namely LiTFSI, dimethoxyethane and dioxolane) within these mixtures was determined by means of gas chromatography and 19F-NMR. It was found that the amount of electrolyte accessible to extraction remains relatively constant during the first 25 cycles, but then continuously decreases within the subsequent 40 investigated cycles. The ratio of the organic constituents of the electrolyte does not change considerably, which means there is no preferred decomposition pathway for either of the two components dioxolane and dimethoxyethane, respectively. These results demonstrate that the capacity fading of a lithium-sulfur cell coincides with the loss of the electrolyte within the cell and there is a strong correlation between the failure of a lithium-sulfur cell and the decomposition reactions of its electrolyte. These findings are supported by a detailed analysis of the gaseous decomposition products after specified cycle numbers. Realistic pouch bag cells are used as test vehicles. Such cells do resemble industrially viable, commercial cells much closer as e.g. coin-type cells: Much lower electrolyte/active mass ratios can be used, thus allowing for a more realistic picture of the failure mechanisms involved.
In the recent years, decentralized power generation using locally available renewable energy resources has been recognized as a cost effective alternative of uneconomical grid extension. The present paper deals with the size optimization of Integrated Renewable Energy System (IRES) for a cluster of villages of Uttarakhand state in India. The proposed IRES consists of locally available renewable energy resources of Micro Hydro Power (MHP), biogas, biomass, wind and solar energy in order to meet the electrical and cooking demands of the study area. A system operation strategy has been developed in the paper for size optimization of IRES. Also, the loss of power supply probability (LPSP) has been used as the reliability criteria in order to ensure the continuous supply of power without any failure problems. Further, in order to utilize renewable energy resources in different contributions, four different resource scenarios are considered for the study area. Finally, the total net present cost (NPC) of the considered scenarios has been optimized using discrete harmony search (DHS) algorithm. Among different scenarios, MHP-biogas-biomass-wind-solar-battery based IRES offers the lowest net present cost of INR 49.0309 million at the estimated LCOE of INR 5.47/kWh.
A high step-up bridgeless single phase ac–dc power factor correction (PFC) rectifier based on Cuk topology is proposed for high voltage battery charger application. The proposed topology is designed to operate in the discontinuous conduction mode (DCM) to achieve the following advantages: simple control, high power factor, soft switching at turn on and low harmonic content of the line input current. In addition, the proposed converter exhibits low inrush current and low magnetic emission rate similar to the conventional Cuk topology. Besides, all the inductors in converter can be coupled on the same magnetic core, hence high power density is also possible. Compared to the conventional Cuk converter, the proposed bridgeless topology has lower conduction losses and higher voltage gain. Simulation and experimental results are presented along with the theoretical analysis.
Spiritual care is an important part of healthcare, especially when facing the crisis of advanced cancer. Do oncology inpatients receive spiritual care consistent with their needs? When inconsistent, are there deleterious effects on patient outcomes?
A novel electroactive polypyrrole (PPy)-threaded HKUST-1 metal-organic framework (MOF) composite film was constructed on an electrode. This was achieved by the in situ conversion of CuO in a PPy/CuO composite film to HKUST-1 MOF by a unipolar pulse electro-erosion (UPEE) and in situ coordination method for the recovery of lithium ions (Li+) with low concentrations in aqueous solutions. The obtained films were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and thermogravimetric analysis. A PPy/HKUST-1 composite film with HKUST-1 anchored in the PPy nanorod networks was successfully formed on the electrode. Extraction of various metal ions, Li+, K+, Na+, Mg2+, and Cu2+ with this film was investigated using the electrochemically switched ion exchange technique. The PPy/HKUST-1 composite film exhibited a high selective extraction ability for Li+ present in low concentrations. The Li+ adsorption capacity reached 37.55 mg/g with an adsorption equilibrium time of less than 25 min owing to the sieving function of the voids and excellent affinity of this film for the Li+ ions. It is expected that such an electroactive film can be applied to the separation and recovery of dilute Li resources from various aqueous solutions.
Aerosol physical size distributions were measured at the South Pole during December 1998 and December 2000 as part of the ISCAT program. The size ranges covered by these measurements were 3 to 250nm in 1998 and 3nm–2μm in 2000. “Typical background aerosols” measured during both periods were similar. Total aerosol number concentrations ranged from 100 to 300cm−3 with occasional spikes as high as 10,000cm−3. We believe the spikes were due to local emissions. The number mean size of background aerosols ranged from 50 to 70nm, and total aerosol surface area concentrations were 2.8±0.4μm2 cm−3. Aerosols measured in December 2000 were cleanly separated into “low volume” and “high volume” periods. During the low-volume periods, volume concentrations were 0.07±0.01μm3cm−3 with a volume mean diameter of 0.27±0.05μm, and these volume concentrations were mostly within a factor two of values that would be expected based on reconstructed mass from particulate chemical composition. Volume concentrations during the “high volume” periods exceed levels that can be explained from aerosol chemistry and calculated light-scattering coefficients exceed values that have been recorded historically. We have been unable to identify why this might have occurred. We observed one 4-h event on December 15, 2000 during which nanoparticles grew slowly from ∼3.0 to 3.6nm.We believe these particles had recently been formed by nucleation. Because this occurred during a period of stagnation, it is possible that this event was associated with local emissions.
The electrodes prepared by a sputtering method were evaluated as the cathodes for direct methanol fuel cells (DMFCs). Pt loading below 0.25mgcm−2 achieved higher mass activities than that of 0.5mgcm−2 prepared by the paste method, which was general conventional method. However, an increase in Pt loading reduced the catalyst activity for the oxygen reduction reaction (ORR). This result may suggest an increase in only electrochemically inactive Pt. Pt utilization efficiency can be found about ten times higher at Pt loading of 0.04mgcm−2. Moreover, addition of Nafion to sputter-deposited Pt cathodes is found possible to improve the catalyst activity for the ORR, but the excess Nafion over the optimum condition reduces the active sites.
In this work, pyromellitic dianhydride-based polyimide was hydrothermally synthesised and further thermally treated to prepare porous carbon materials. The porous structure of the polyimide-derived carbon can be controlled by varying the reactant concentrations during the hydrothermal reaction and KOH activation to achieve a highly accessible specific surface area of 1302 m2 g−1. A hybrid sodium-ion capacitor fabricated with the polyimide as anode and the polyimide-derived carbon as cathode can be operated at a voltage of 4.2 V, delivering an energy density of 66 Wh kg−1 at power density of 196 W kg−1, and an energy density of 13.3 Wh kg−1 at power density of 1200 W kg−1.
Sodium ion batteries are attracting great attention due to the naturally alternative energy storage for large-scale applications. The reliable and high performance cathode materials are urgently needed for their practical applications. Here, we report sodium iron–nickel hexacyanoferrate (FeNiHCF) with Prussian blue structure by substitution of a portion of iron ions with nickel ions, and characterize it as cathode material of sodium ion battery for the first time. The low-spin Fe2+/Fe3+ couple in FeNiHCF is sufficiently activated for sodium storage, which leads to higher capacity contribution at larger potential and better stability on redox energy comparing with the single metal hexacyanoferrate of FeHCF or NiHCF. The FeNiHCF cathode presents synergistic advantages of high capacity, remarkable cycling stability, superior rate capability and good Coulombic efficiency. Significant improvement on electrochemical performance have been achieved with a discharge capacity of 106 mAh g−1, a Coulombic efficiency of ∼97% and excellent capacity retention of 96% over 100 cycles. Impressively, the FeNiHCF cathode present a good and stable cycling at high current densities, e.g. a capacity of 71 mAh g−1 and 100% capacity retention at a current density as high as 500 mA g−1. The intercalation chemistry manner for improving the sodium storage of material may shed light on improving the Na-storage performance of Prussian blue analogues.
Electrochemical deposition of a metal onto a foreign substrate usually occurs by an island growth mechanism. A key feature of island growth for a material M on a foreign substrate S is that the onset potential for deposition is shifted negative from the equilibrium potential for the metal ion couple. The nucleation overpotential, defined as η n(M +/S)=|U n(M +/S)− U eq(M +/M)|, influences key aspects of deposition of a metal on a foreign substrate. Here we discuss how the nucleation overpotential influences the kinetics of island growth, the implications of the nucleation overpotential on island shape and orientation, and the consequences of the coupling between the island density (applied potential) and the island size at coalescence (grain size). We then discuss the kinetics of island growth in terms of the contributions to vertical and lateral growth. Finally, we present examples of experimental methods to manipulate the nucleation overpotential and overcome some of the limitations imposed by the nucleation overpotential.
Sn–Co alloy films were prepared by electroplating on copper and used as anode material of lithium ion battery. Cyclic voltammetry and galvanostatic discharge/charge measurements were combined with surface analysis by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results show the buildup of a solid electrolyte interphase (SEI) layer formed by reductive decomposition of electrolyte during the first Li–Sn alloying cycle. The layer is constituted of a mixture of Li2CO3, ROCO2Li, lithium oxalates, and/or ROLi, and its chemical composition is modified during the electrochemical multi-cycling process with increase of the Li2CO3 content. Multi-cycling also fractures the SEI layer. ToF-SIMS results revealed an incomplete initial alloying process of lithium ion with Sn, limited by mass transport through a Co layer and dividing the Sn–Co layer alloy into a fully lithiated outer part and an essentially non-lithiated inner layer during the first discharge. The volume expansion/shrink associated with the alloying/dealloying reaction irreversibly cracks and splits up the Sn–Co alloy into particles with interstitials voids filled by the SEI layer. Multi-cycling amplifies this division of the Sn–Co layer without material loss and stabilizes discharge/charge capacity.
We report a solvent-free dry powder coating process for making LiNi1/3Mn1/3Co1/3O2 (NMC) positive electrodes in lithium-ion batteries. This process eliminates volatile organic compound emission and reduces thermal curing time from hours to minutes. A mixture of NMC, carbon black, and poly(vinylidene difluoride) was electrostatically sprayed onto an aluminum current collector, forming a uniformly distributed electrode with controllable thickness and porosity. Charge/discharge cycling of the dry-powder-coated electrodes in lithium-ion half cells yielded a discharge specific capacity of 155 mAh g−1 and capacity retention of 80% for more than 300 cycles when the electrodes were tested between 3.0 and 4.3 V at a rate of C/5. The long-term cycling performance and durability of dry-powder coated electrodes are similar to those made by the conventional wet slurry-based method. This solvent-free dry powder coating process is a potentially lower-cost, higher-throughput, and more environmentally friendly manufacturing process compared with the conventional wet slurry-based electrode manufacturing method.
The construction of smart homes under the infrastructure of smart grids (or micro grids) is currently one of the most important topics in the field of smart energy systems. Demand-side management confers many benefits on both users and utility companies. This paper proposes a novel scheduling procedure for power consumption in homes equipped with energy storage devices. The proposed optimal power scheduling method can reduce electricity bills and improve peak-to-average ratio (PAR) while taking into account the comfort of residents. Real-time pricing combined with an inclining block rate (IBR) tariff is used to prevent high power consumption at times of low cost, and to simultaneously improve the PAR index. Because erroneous determination of the state of the charge of storage systems can have deleterious effects on PAR, a revised formulation is therefore applied to attain the best solution of the problem. Home devices and batteries are modelled in a practical and efficient manner. The proposed multi-objective optimization problem is solved with non-dominated sorting genetic algorithm (NSGA-II) using MATLAB software. Then fuzzy decision is applied to obtain the most preferred solution.
A solid oxide fuel cell (SOFC) with a liquid antimony anode is fabricated based on a smooth single crystal YSZ electrolyte substrate and a porous Pt cathode. The performance of the liquid antimony anode was tested under “battery mode”, with the anode chamber shielded in argon throughout the test and the cathode exposed to air. Polarization curves were taken and a long term constant potential discharging test was carried out afterwards. Taking electrochemical reaction, mass transport and microstructure of the liquid Sb anode into consideration, a one dimensional mathematical model was built and then validated by the polarization curve and the constant potential discharging performance curve obtained during the test. This model analyzes the metallic Sb distribution in the anode during cell operation, explains the cell performance evolution base on the microstructural development of the liquid Sb anode and simulates how the anode microstructure affects the cell performance.
Research interest in alkaline aqueous batteries has surged worldwide due to their merits of low cost and high safety. However, the development of practical high-energy Ni–Zn batteries has been beset by the bias between industrial application with gravimetrical energy limits and scientific research with volumetrical shortages. Herein, we propose a facile top-down strategy to prepare low-cost and ultra-dense Co-free microscale cathodes for Ni–Zn batteries. Based on the anion exchange and Kirkendall effect, this commercially viable technology is capable of permeating the matrix of microspheres with uniform and robust adherence of NiS nanodots and abundant mesopores. The enhanced proton-diffusion kinetics endows the Ni–Zn battery with impressive areal capacity (41.3 mA h cm−2) and a fast power response of 715 mW cm−2, together with 80000 transient pulse cycles. A best practice for systematic measuring of aqueous batteries in a more practical metric is proposed. As a proof of concept, we demonstrate a commercial-grade 3.5 A h Ni–Zn pouch battery, which concomitantly presents record-high energy densities of 165 W h kg−1 gravimetrically and 506 W h L−1 volumetrically based on the whole battery. The cost is estimated conservatively at US $32.8 kW h−1 on a device scale. These results provide a new opportunity to advance high-energy Ni–Zn batteries and should be of immediate benefit toward low-cost, practical energy storage and grid-scale applications.
The prospect of small fuel cells replacing batteries in portable equipment is considered in terms of their prospective energy density, technological feasibility, safety and cost. Fuel cells seem to be best suited to applications where significantly more energy storage is required than at present in portable devices (>20Wh). Energy requirements (Wh) are likely to increase with the introduction of broadband mobile computing, and fuel cells with lightweight fuel supplies could dramatically increase the amount of energy available in the same volume. However, in contrast to batteries, since the energy source and the energy converter are separated, a fuel cell system adds complexity and associated safety and reliability issues will need to be carefully assessed for portable applications. However, the prospective commercial market for high energy density power sources is attractive enough to support significant development and accelerate the introduction of small fuel cells since battery technology is unlikely to be able to meet the growing energy demands of a mobile workforce.
The Micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica Solida Sinica, is devoted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30th anniversary of Acta Mechanica Solida Sinica, its editor-in-chief, Professor Q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. §I firstly brings in focus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. §II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In §III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in §IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.
The involvement of brain structures in specific cognitive functions is not straightforward. In order to characterize the brain micro-structural correlates of cognitive domains, 52 healthy subjects, age 25–82 years, completed a computerized neuropsychological battery and were scanned using magnetic resonance diffusion tensor imaging. Factor analysis of 44 different cognitive scores was performed, isolating three cognitive domains—executive function, information processing speed and memory. Partial correlation was conducted between DTI parameters and each of the three cognitive domains controlling for age and motor function. Regions showing significant correlations with cognitive domains are domain-specific and are consistent with previous knowledge. While executive function was correlated with diffusion tensor imaging (DTI) parameters in frontal white matter and in the superior longitudinal fasciculus, information processing speed was correlated with DTI parameters in the cingulum, corona radiata, inferior longitudinal fasciculus, parietal white matter and in the thalamus. Memory performance was correlated with DTI measures in temporal and frontal gray matter and white matter regions, including the cingulate cortex and the parahippocampus. Thus, inter-subject variability in cognitive performance and tissue morphology, as expressed by diffusion tensor magnetic resonance imaging, can be used to relate tissue microstructure with cognitive performance and to provide information to corroborate other functional localization techniques.
This paper uses a one-dimensional, physics-based model of a valve-regulated lead-acid (VRLA) battery to examine the impact of demand response on uninterruptible power supply (UPS) availability in a datacenter. Datacenters are facilities that provide services such as cloud computing, web search, etc. They are also large electricity consumers. An energy-efficient 15 MW datacenter, for instance, may pay $1 m per month for electricity. Datacenters often utilize VRLA batteries to ensure high reliability in serving their computational demand. This motivates the paper's central question: to what extent does the use of datacenter UPS batteries for demand response affect their availability for their primary purpose (namely, emergency power)? We address this question using a physics-based model of the coupled diffusion-reaction dynamics of VRLA batteries. We discretize this model using finite differences, and simulate it for different datacenter battery pack sizes. The results show that for a typical datacenter power demand profile, a VRLA battery pack sized for UPS functionality can provide demand response with only a minimal loss of UPS availability.