batterydata/paper-abstracts huggingface dataset:
ABSTRACT Lithium-ion capacitors (LICs) are assembled with activated carbon (AC) cathode and pre-lithiated mesocarbon microbeads (MCMB) anode. For ensuring the electrochemical performance of LIC, the pre-lithiation capacity of MCMB anode is designed to make the anode at the two lithium ion intercalation plateaus. The utilization of the two plateaus greatly affects the charge-discharge process and behavior at different working potential ranges of LIC, which achieves the regulation of the electrochemical performance. LIC150 using the first plateau of MCMB anode exhibits higher power density and superior cycle performance, and LIC300 using the second plateau of MCMB anode shows higher energy density. The two plateaus utilization of the MCMB anode can be further increased by improving the working potential range. LIC150 and LIC300 display the optimal electrochemical performance at the working potential range of 2.0-4.0V. LIC150 exhibits high power density of 6.3kWkg−1 and the energy density up to 62.9Whkg−1, capacity retention of 93.4% after 1000 cycles. Besides, the energy density of LIC300 is up to 92.3Whkg−1, the power density as high as 5.5kWkg−1 and excellent capacity retention of 97.0% after 1000 cycles.
This work describes the detailed studies performed on the nanocomposite composed of chemically-modified multiwall carbon nanotubes covered by hematite nanoparticles which diameters vary from 10nm to 70nm. This nanomaterial was fabricated in two-steps facile chemical synthesis and was characterized with the use of several experimental techniques, such as: thermogravimetric analysis, differential thermal analysis, Raman spectroscopy, X-ray diffraction, and transmission Mössbauer spectroscopy in order to determine its structure precisely. Moreover, the investigated nanocomposite was tested as an anode material of Li-ion batteries. Its cycling performance was stable during 40 cycles, while its capacity was retained at the level of 330 and 230 mAh/g at the discharge/charge rate of 25 and 200mA/g, respectively.
Molybdenum disulfide (MoS2) has been extensively investigated as the key material for post-silicon electronics, optoelectronics (flexible devices), Li-ion batteries, solar cells, etc. In the work presented, MoS2 nanoparticles (NPs) were obtained via the laser (Nd:YAG, λ = 1064 nm) ablation of a bulk MoS2 in ethylene glycol solution, as a function of the laser fluence, for the first time. The properties of the product were characterized using UV–vis, TEM, SAED, SEM with EDX, XRD, FT-IR, and Raman spectroscopy. The results showed that the synthesized MoS2 NPs have a hexagonal crystalline structure with diameters of 4–160 nm. In addition, most of them had a rounded shape whose λmaxvaried from 212.5 to 216.5 nm depending on the laser fluence. By increasing the laser fluence, the average size of these particles increased from 10 to 18 nm. The shape and size of MoS2 NPs have a significant role in the fields of lubrication, catalysis, electrocatalysis, etc. Laser ablation method is a clean, simple, and reproducible way to produce nanostructures with special properties.
In this Case Study, a 66-year-old man presented with a clinical syndrome consistent with frontal variant frontotemporal dementia, but neuropathological evidence established a diagnosis of frontal variant Alzheimer's disease. The authors provide detailed, longitudinal clinical data describing the course of this rare but increasingly recognized variant of Alzheimer's disease.
The electrochemical performance as potential anodes in lithium-ion batteries of several boron-doped and non-doped graphitic foams with different degree of structural order was investigated by galvanostatic cycling. The boron-doped foams were prepared by the co-pyrolysis of a coal and two boron sources (boron oxide and a borane–pyridine complex), followed by heat treatment in the 2400–2800°C temperature interval. The extent of the graphitization process of the carbon foams depends on boron concentration and source. Because of the catalytic effect of boron, lightweight graphite-like foams were prepared. Boron in the foams was found to be present as carbide (B4C), in substitutional positions in the carbon lattice (B–C), bonded to nitrogen (B–N) and forming clusters. Larger reversible lithium storage capacities with values up to ∼310mAhg−1 were achieved by using the boron oxide-based carbon foams. Moreover, since the electrochemical anodic performance of these boron-doped foams with different degree of structural order is similar, the beneficial effect of the presence of the B–C boron phase was inferred. However, the bonding of boron with nitrogen in the pyridine borane-based has a negative effect on lithium intercalation.
We present a method to produce a physics-based one-dimensional discrete-time state-space reduced-order model (ROM) of a lithium-ion cell. The resulting ROM can predict the five variables of a standard porous-electrode model—reaction flux, solid and electrolyte lithium concentration, and solid and electrolyte potentials—at any location across the cell cross section, as well as cell terminal voltage. The method to generate the model involves first linearizing the porous-electrode-model equations, and then deriving closed-form Laplace-domain transfer functions from the linearized equations. Next, the discrete-time realization algorithm (DRA) is used to convert the transfer functions into an optimal discrete-time state-space realization. Advantages of this approach include that the DRA avoids nonlinear optimization and gives a straightforward method for selecting the system order for the ROM. Simulation results demonstrate that the ROM cell voltage predictions and the ROM internal electrochemical variable predictions match very closely with results obtained by simulating the full nonlinear porous-electrode partial differential equations.
Layer structured Ni-rich oxides with high energy density suffer from an aggressive side reaction at the deep-charged state, resulting in consequent structure collapse and capacity fading. Herein, a facile modification strategy has been developed by designing electrochemically stable lithium-rich layered oxides as the shell and high-energy-density Ni-rich oxides as the core. Mn2+, Co2+, and Ni2+ solutions are introduced to form Mn0.54Ni0.13Co0.13(OH)1.6, which is homogeneously coated on LiNi0.80Co0.15Al0.05O2 composite. Materials incorporating advantages of Ni-rich oxides and layered over-lithiated oxides are obtained after simple heat treatment. Li1.20Mn0.54Ni0.13Co0.13O2 coating improves the cycling performance of LiNi0.80Co0.15Al0.05O2 pronouncedly even at a high cut-off voltage. 1% layered over-lithiated oxide modified materials show discharge capacities of 196.6, 188.8, and 182.9 mAh g−1 at the rates 0.2, 0.5, and 1 C, respectively, in square full-cells between 2.8 and 4.35 V, and display an improved cycling performance with 82.6% capacity retention during 1000 cycles at 1 C rate.
The electrochemical properties of Li2SiS3 were investigated in a solid electrolyte. Li2SiS3 was converted to elemental Si, and the resultant Si was formed into Si–Li alloy in the reduction process; however, the reverse reaction was not completed due to the loss of electronic conduction upon reoxidation. FeS was dispersed as a conductive additive in Li2SiS3 films by pulsed laser deposition (PLD). The addition allowed successive reactions to proceed at a large capacity with small capacity-fading during the cycling process in spite of the small FeS fraction. This result indicates that Li2SiS3 +FeS thin film is a promising anode for solid-state lithium batteries.
The cycling performance of Si-nanoparticle/Li cells with different electrolytes has been investigated. Cells containing standard binary LiPF6/ethylene carbonate/ethyl methyl carbonate electrolytes have poor capacity retention (46 %) after 50 cycles. Cells cycled with fluoroethylene carbonate (FEC)-based electrolyte have much better capacity retention (74 %). The effect of incorporation of flame-retardant co-solvents triphenyl phosphate and dimethyl methylphosphonate was investigated with both the standard and FEC electrolytes. The incorporation of the FR co-solvents did not significantly alter the performance of either electrolyte. Ex situ analysis via scanning electron microscopy, attenuated total reflectance infrared spectroscopy, and X-ray photoelectron spectroscopy was conducted to gain a better understanding of the role of electrolyte in solid electrolyte interphase structure and stability.
Carbonaceous air cathodes with rational architecture are vital for the nonaqueous Li–O2 batteries to achieve large energy density, high energy efficiency and long cycle life. In this work, we report the cathodes made of highly ordered and vertically aligned carbon nanotubes grown on permeable Ta foil substrates (VACNTs-Ta) via thermal chemical vapour deposition. The VACNTs-Ta, composed of uniform carbon nanotubes with approximately 240 μm in superficial height, has the super large surface area. Meanwhile, the oriented carbon nanotubes provide extremely outstanding passageways for Li ions and oxygen species. Electrochemistry tests of VACNTs-Ta air cathodes show enhancement in discharge capacity and cycle life compared to those made from short-range oriented and disordered carbon nanotubes. By further combining with the LiI redox mediator that is dissolved in the tetraethylene dimethyl glycol based electrolytes, the batteries exhibit more than 200 cycles at the current density of 200 mA g−1 with a cut-off discharge capacity of 1000 mAh g−1, and their energy efficiencies increase from 50% to 82%. The results here demonstrate the importance of cathode construction for high-energy-efficiency and long-life Li–O2 batteries.
Chemistry and applicability of ionic liquids (IL), – organic salts with low melting point – are in the focus of interest today. The ILs with melting point below room temperature are expected to be good solvents. Their applicability in organic synthetic work, in separation processes as well as in electrochemistry is very promising. In the work reported here the voltammetric behavior of ferrocene in 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+ PF6 −) ionic liquid has been investigated. Conventional size and micro platinum and carbon electrodes were employed in CV and in chronoamperometric measurements. Karl Fischer method was used for the determination of water content of the solvent. Voltammetric measurements without addition of background electrolyte could be carried out in (BMIM+ PF6 −) ionic liquid. A broad potential window could be used. Concentration dependence of the electrochemically determined diffusion coefficient of the ferrocene was observed.
Nocardia brasiliensis is a rare human pathogen usually associated with localized cutaneous infections.
Objective The principal objective of this study was to investigate the relationship between insomnia and health-related quality of life (HRQoL) during the early stage of stroke rehabilitation. Methods The subjects were 214 first-time stroke patients admitted to a rehabilitation unit at one of three Korean hospitals. Within 7days after stroke, functions were evaluated using; the Berg Balance Scale, the Modified Barthel Index, the Mini Mental State Examination, the Frontal Assessment Battery, Screening Tests for Aphasia and Neurologic-Communication Disorders, and the National Institute of Health Stroke Scale. Insomnia, depression, anxiety, and HRQoL were investigated at one month after stroke. Insomnia was defined as presence of at least one of the four following; difficulty initiating sleep, difficulty maintaining sleep, early morning awakening, and non-restorative sleep. HRQoL was assessed using the Short Form Health survey SF-8. Depression and anxiety were measured using the Hospital Anxiety Depression Scale. Multivariate linear regression analysis was conducted to examine the association between insomnia and HRQoL. Results The prevalence of insomnia at one month after stroke was 59.5%. Patients with insomnia were more likely to be older and female and to have depression and anxiety. Patients with insomnia had poorer physical and mental HRQoL. By multivariate analyses, physical HRQoL was significantly associated with type of stroke, hypnotic usage, balancing function, and insomnia. Mental HRQoL was significantly associated with balancing function, depression, and insomnia. Conclusion Insomnia was found to be negatively associated with physical and mental HRQoL in stroke patients during the early stage of rehabilitation.
Alkaline fuel cells (AFCs) are promising power sources due to superior kinetics and the ability to use inexpensive non-noble metal catalysts. However, carbonate formation from carbon dioxide in air has long been considered a significant hurdle for liquid electrolyte-based AFC technologies. Carbonate formation consumes hydroxyl anions, which leads to (i) reduced electrode performance if formed salts precipitate from solution and (ii) lowered electrolyte conductivity, which reduces cell performance and operating lifetime. Here, using a flowing electrolyte-based microfluidic fuel cell, we demonstrate that AFC performance can be resilient to a broad range of carbonate concentrations. Furthermore, we investigate the effects of carbonate formation rates on projected AFC operational lifetime. Results from this study will aid in the design of AFC-based power sources in light of the tradeoffs between performance, durability and cost.
The electrochemical performance of self-organized TiO2 nanotubes (TiO2nts) can be improved for lithium-ion microbatteries by depositing submicron Co3O4 and NiO particles. These transition metal oxides were directly grown onto the titania nanotubes by electrodeposition and thermal treatments. The morphology and the chemical composition of the resulting materials were characterized by scanning electron microscopy (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS), and X-Ray Diffraction (XRD). The electrochemical nucleation and growth mechanisms of Co and Ni onto TiO2nts are also discussed. Besides the remarkable capacity retention of the nano-architectured titania electrodes in lithium test cells, we show that the addition of submicron Co3O4 or NiO particles leads to a spectacular increase of the capacity values during the first 25 cycles.
The electrochemical behaviour of a range of halide and titanium halide redox couple combinations has been evaluated for potential application in redox flow cells employing common elements in both half-cells. Cyclic voltammetry and cell cycling measurements were employed to establish the reversibility of the redox couples and the expected cell voltage and performance in a redox flow cell. An all iodine cell was found to be impractical due to the formation of an insoluble iodine deposit in the cell that caused cell blockage. A titanium polyhalide cell that uses a solution of TiCl4 in HBr/HCl supporting electrolyte in both half-cells was, however, shown to produce an open circuit voltage of 0.9 V and high coulombic efficiencies. Although the voltage efficiency of the cell was low, improvements in cell design may reduce ohmic losses allowing much higher energy efficiencies to be achieved. This cell is equivalent to the vanadium bromide cell that employs a vanadium bromide solution in both half-cells. The lower price of titanium, however, opens the possibility of a significant cost benefit for the titanium polyhalide redox flow cell.
Reticulated vitreous carbon (RVC®) and RVC® plated with lead were investigated as carriers for the negative electrode of lead-acid cell. The RVC® and Pb/RVC® carriers were pasted with active paste (received from JENOX Ltd., Polish producer of lead-acid batteries) and prepared to be used in lead-acid cell. Comparative study of electrodes based on RVC® and Pb/RVC® has been done using constant-current charging/discharging, constant-potential discharging and cycling voltammetry measurements. Scanning electron microscopy (SEM) was employed to determine the morphology of the lead layer deposited on the RVC surface. Hybrid flooded single lead-acid cells containing one negative electrode, based on new type of carrier (RVC® or Pb/RVC®), sandwiched between two positive electrodes, based on the Pb–Ca grids, were assembled and subjected to electrochemical tests. It has been found that both materials, RVC® and Pb/RVC®, can be used as carriers of negative electrode, but the latter seems to have better influence on the discharge performance.
This study evaluates whether patients with schizophrenia have a degraded memory store for semantic knowledge. 20 patients with a chronic history of schizophrenia and evidence of cognitive impairment were selected, since the literature indicates that this subgroup is most likely to manifest a degraded semantic knowledge store. Their profile of semantic memory impairments was compared to that of a group of Alzheimer's Dementia (AD) patients (n =22), who met neuropsychological criteria for degraded semantic store. Both groups were matched for Performance IQ. 15 elderly healthy controls were also included in the study. The AD and schizophrenia groups produced substantially different profiles of semantic memory impairment. This is interpreted as indicating that the semantic impairments in this subgroup of patients with schizophrenia do not result from a degraded store. This is corroborated by an analysis of the data using other neuropsychological criteria for determining degraded store. We conclude that there is little evidence for a classic degradation of semantic knowledge in schizophrenia, and it appears that impairments result from an inability to use semantic knowledge appropriately, particularly when selection of salient semantic relations is required.
Hyperbranched thin film (HTF) with amino and imino groups, which can accommodate PtCl6 2−, was synthesized with small organic molecules on gold substrate based on SN2 displacement reaction. Platinum nanoparticles (PtNPs) were in situ synthesized by electrochemically reduction of precursors, PtCl6 2−, within HTF. The prepared films were characterized by X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM). It was confirmed that densely packed PtNPs were prepared with a narrow size distribution. EIS indicated that HTF inhibits electron transfer slightly while Pt nanoparticles in the HTF enhanced the electron-transfer ability greatly. Cyclic voltammetry (CV) indicated that HTF containing PtNPs exhibited a remarkable electrocatalytic activity for the electrochemical reduction of dioxygen. The quantity of PtNPs could be expediently controlled by the thickness of HTF. So the catalytic ability can be tailored correspondingly.
The design of intelligent autonomous systems able to sense, react and control the environment or complex processes has been a long term research desideratum. By integrating the concepts of mobile multi-robot systems and wireless sensor and actuator networks into a single framework, a powerful technology can be obtained, promising to serve as a backbone for complex distributed and mobile control applications. In this context new research challenges and opportunities have opened up. This paper defines the new integrated concept of wireless sensor, actuator and robot networks, surveys the current state-of-art in the field and presents design requirements and open research issues.
The study presents the possibility of preparation of multi-membrane gel systems with different morphologies and properties, based on poly(N,N-dimethyl-acrylamide-co-3,9-divinyl-2,4,8,10-tetraoxaspiro (5.5) undecane) copolymer and crosslinked with N,N′-methylene-bis-acrylamide. The basic copolymer has dual thermo- and pH sensitive character. After the core hydrogel is realized, the preformed gel is immersed in the aqueous solutions of ammonia, sodium chloride and sodium citrate for further edge constructing of the supramolecular assemblies. Then, the new layers by adding new sets of gelifying components are realized. The new multi-membrane gel systems are intended to be used as matrix for bioactive substances embedding. In this context the systems were loaded with norfloxacin as drug model. The in vivo tests show good biocompatibility for the implants based on multi-membrane gel structures loaded with drug.
To realize the optimal energy allocation between the engine-generator and battery of a hybrid tracked vehicle (HTV), a reinforcement learning-based real-time energy-management strategy was proposed. A systematic control-oriented model for the HTV was built and validated through the test bench, including the battery pack, the engine-generator set (EGS), and the power request. To use effectively the statistical information of power request online, a Markov chain-based real-time power request recursive algorithm for learning transition probabilities was derived and validated. The Kullback–Leibler (KL) divergence rate was adopted to determine when the transition probability matrix and the optimal control strategy update in real time. Reinforcement learning (RL) was applied to compare quantitatively the effects of different forgetting factors and KL divergence rates on reducing fuel consumption. RL has also been used to optimize the control strategy for HTV, compared to preliminary and dynamic programming-based control strategies. The real-time and robust performance of the proposed online energy management strategy was verified under two driving schedules collected in the field test. The simulation results indicate the proposed RL-based energy management strategy can significantly improve fuel efficiency and can be applied in real time.
The open circuit voltage (OCV) is of essential importance for accurate estimation of the state of charge (SoC) in lithium-ion battery (LiB). The OCV-SoC relationship is typically predetermined by fitting offline OCV data. Commonly used two OCV tests are compared in few literatures. Moreover, they only focus on the middle SoC region (i.e., 20% and 90%) of LiNiMnCoO2 (NMC) LiBs, the performances of these OCV tests for other battery types and entire SoC region are failed to be addressed. In this paper, the impact of two OCV tests on SoC estimation for NMC and LiFePO4 (LFP) LiBs is investigated at different temperatures and aging stages. A parameter and SoC joint estimation method is introduced, based on an integrated H∞-UKF method. The accuracy and reliability of the proposed method are verified by using two different OCV testing data at various ambient temperatures and aging stages for some commercial NMC and LFP LiBs. The results indicate that the incremental OCV test method results in more accurate SoC estimation than the low current OCV test method, on both NMC and LFP LiBs. Furthermore, to reach equilibrium states and achieve desired SoC estimation accuracy, the relaxation period in the incremental OCV test method needs to be extended at low temperatures.