batterydata/paper-abstracts huggingface dataset:
The objective of this work is to examine the effects of humidity of reactant fuel at the inlet on the detailed gas transport and cell performance of the PEM fuel cell with baffle-blocked flow field designs. It is expected that, due to the water management problem, the effects of inlet humidity of reactant fuel gases on both anode and cathode sides on the cell performance are considerable. In addition, the effects of baffle numbers on the detailed transport phenomena of the PEM fuel cell with baffle-blocked flow field are examined. Due to the blockage effects in the presence of the baffles, more fuel gas in the flow channel can be forced into the gas diffuser layer (GDL) and catalyst layer (CL) to enhance the chemical reactions and then augment the performance of the PEMFC systems. Effect of liquid water formation on the reactant gas transport is taken into account in the numerical modeling. Predictions show that the local transport of the reactant gas, the local current density generation and the cell performance can be enhanced by the presence of the baffles. Physical interpretation for the difference in the inlet relative humidity (RH) effects at high and low operating voltages is presented. Results reveal that, at low voltage conditions, the liquid water effect is especially significant and should be considered in the modeling. The cell performance can be enhanced at a higher inlet relative humidity, by which the occurrence of the mass transport loss can be delayed with the limiting current density raised considerably.
To realize electrochemical impedance spectroscopy (EIS) using a simple measurement system, application of a square potential/current waveform to the input signals of EIS was investigated. The impedance of a simple redox reaction of [Fe(CN)6]4−/[Fe(CN)6]3− solution was measured by the potentio-EIS using a square waveform as the input signal, which was generated by a potentiostat system without a frequency response analyzer (FRA). A steady impedance response in the frequency range of 40 Hz–3.5kHz was obtained, and the impedance was obtained by the potentiostat system with an FRA. The errors—the differences between the impedance measured by EIS with a square potential waveform and that of conventional EIS—were sufficiently low to allow impedance analysis. The impedance of a lithium-ion battery (LIB) was measured by galvano-EIS using a square waveform input signal generated by a power controller. A steady impedance response in the frequency range of 5 Hz–2.5kHz was obtained, and the errors were sufficiently low to allow impedance analysis. It was demonstrated that both square potential-EIS (SP-EIS) and square current-EIS (SC-EIS) have great potential as simple systems for measuring impedance. Moreover, it was demonstrated that SC-EIS has potential as a simple measurement system for analyzing the state of an LIB. Thus, the potential of the SP/SC-EIS methodology was confirmed for electrochemical systems.
Solid polymer electrolytes (SPEs) with high ionic conductivity and acceptable mechanical properties are of particular interest for increasing the performance of batteries. Our previous studies indicated that copolymers could be good candidates for SPE materials due to the variable properties contributed by each block. A series of copolymers applied in this research was poly(ethylene oxide)-block-polyethylene, PEO-b-PE, which contains a conductive block (PEO block) and a reinforcement block (PE block). This study examines the effects of composition and molecular weight of the copolymers on performance of the resulting SPEs. The ternary SPEs were prepared by addition of copolymers into PEO/LiClO4. It was found that increasing the PE block percentage in the copolymer resulted in a significant increase in both ionic conductivity and mechanical properties. The SPEs that contained the highest percentage of PE block, 80wt%, exhibits the best performances. The results showed an increase of more than two orders in ionic conductivity, about 350% increase in tensile modulus, and about 97% increase in ultimate tensile strength when the PE block increased from 50wt% to 80wt%. It was also observed that increasing the molecular weight of the copolymer resulted in better mechanical properties, and an identical ionic conductivity.
Nano-engineered electrodes, such as porous LiCoO2, exhibit improved electrochemical performance compared to the non-porous LiCoO2 analogue. Structural studies of the pore walls composing the nanostructured LiCoO2 materials have focused on long-range (diffraction) methods. However, the powder diffraction patterns of the low-temperature (LT) and high-temperature (HT) phases of non-porous LiCoO2 are very similar and distinguishing the two phases can be challenging. In this work, infrared and Raman spectroscopy are used to unambiguously assign the LiCoO2 crystalline domains present in two porous compounds (nanowire LiCoO2 and mesoporous LiCoO2) as LT-LiCoO2. Moreover, the appearance of new bands in the infrared spectrum of LiCoO2 nanowires might signal the presence of disordered LiCoO2 domains that are XRD silent.
A critical parameter for the large-scale integration of solid-state batteries is to establish processing strategies to assemble battery materials at the lowest processing temperature possible while keeping lithium conduction up. Despite extensive research efforts, integrating ceramic film electrolytes while keeping a high lithium concentration and conduction at a low processing temperature remains challenging. Here, we report an alternative ceramic processing strategy through the evolution of multilayers establishing lithium reservoirs directly in lithium–garnet films that allow for lithiated and fast-conducting cubic solid-state battery electrolytes at unusually low processing temperatures. A lithium–garnet film processed via the multilayer processing approach exhibited the fastest ionic conductivity of 2.9 ± 0.05 × 10−5 S cm−1 (at room temperature) and the desired cubic phase, but was stabilized at a processing temperature lowered by 400 °C. This method enables future solid-state battery architectures with more room for cathode volumes by design, and reduces the processing temperature.
Solid Oxide Fuel Cells (SOFCs) are emerging as potential energy conversion devices owing to their high efficiencies and less greenhouse gas emissions. Though there are reviews on this topic, comprehensive reports are very limited. The performance of any SOFC depends on effective functioning of its main constituents like cathode, anode and electrolyte, besides critical accessories like interconnects and seals. Nature of fuel employed and the electrochemical reactions with inherent mechanisms, kinetics and thermodynamic aspects also play a predominant role in extracting the best performance from SOFCs. In this review, various aspects related to SOFCs like materials-composition, fabrication techniques in various configurations, properties and performance; characterization tools to assess the functioning of SOFCS; corrosion-types, mechanism and mitigation methods; integration protocols of SOFC with other power generation devices are thoroughly discussed. Future challenges and prospects in each aspect are presented for prospective researchers.
The current tendency towards product differentiation in many fields of manufacturing is generally considered to be a positive phenomenon. What we have attempted to do here is to verify the real degree of diversification that exists within the computer industry, by means of the measurement of global performance for the most widely spread models, calculated using technical specifications available from the market. The available data enable us to evaluate the actual degree of diversification, and to calculate the price/global performance ratio. This ratio is a measure of the relationship between the global performance of any given product and its price, and provides a critical insight into the technical and economic results of product diversification.
A significant but previously unquantified factor in anthropogenic change in Australian rivers was the release of large volumes of sediment produced by gold mining in the 19th century. This material, known historically as ‘sludge’, rapidly entered waterways adjacent to mining areas and caused major environmental damage. We interrogate detailed historical records from the colony of Victoria spanning the period 1859 to 1891 to reconstruct the temporal and spatial distribution of sediment volumes released by mining activity. Based on these records, we estimate that at least 650 million m3 of material was released into rivers in the 19th century, exceeding natural sediment yield to rivers by an average 140 times. Although the sediment yield per river is not high when compared with examples around the world, the widespread impacts of sludge distinguishes the case of Victoria. The sludge affected three-quarters of catchments in the state due to the large number of small mining operations spread over hundreds of creeks and gullies across the colony. The impacts of sludge to rivers and farmland filled newspapers for more than 50 years and generated numerous parliamentary inquiries. Today, the impacts are largely forgotten and unrecognised, as are the continuing impacts on aquatic systems. The estimates generated in this study provide a basis for understanding the continuing impact of historical mining on Victorian rivers.
Size-controlled hierarchical V2O5 hollow microspheres with tunable nanoscale building blocks were synthesized using a novel solvothermal reaction in the presence of poly (vinylpyrrolidone) (PVP), and their formation mechanism was suggested. The effect of microsphere size and building block shape on the lithium storage properties was also discussed. The size of V2O5 hollow microspheres was controlled by the variation of solvothermal reaction time owing to the splitting of PVP-based micelles by the enhanced movement of chains in PVP. In addition, the morphology variation of V2O5 building blocks in V2O5 hollow microspheres from nano-cuboid to nano-platelet was achieved. The hollow V2O5 microspheres with a smaller sphere size and assembled nano-plates showed a high discharge capacity (292 mA h/g at 44.5 mA/g) and improved rate performance than that of the microspheres with a higher sphere size and assembled nano-cuboids. Such enhanced electrochemical properties of hollow V2O5 microspheres during the lithium insertion/extraction can be attributed to the improved surface area, agglomeration resistances, and short diffusion path of lithium ion in the nanoscale 2D V2O5 plates.
Porous Fe2O3 nanotubes have been fabricated by annealing the electrospun precursor nanofibers. Moreover, the mechanism for the formation of the controllable Fe2O3 nanostructures is investigated through manipulating the concentration of the electrospun precursor solution and also discussed based on their morphological evolution processes. When evaluated as anode materials for lithium-ion batteries, the porous Fe2O3 nanotubes exhibit good lithium storage performance with high specific capacity of 1407.9mAhg−1 and good cycling stability (stable up to 250 cycles), which is attributed to the unique morphology of the porous, hollow and continuous one dimensional (1D) nanostructures. These results demonstrate that further improvement or optimization of electrochemical performance in metal oxide-based electrode materials could be realized by the design of 1D nanostructures with unique morphologies.
Objective Working memory impairment is well established in psychotic disorders. However, the relative magnitude, diagnostic specificity, familiality pattern, and degree of independence from generalized cognitive deficits across psychotic disorders remain unclear. Method Participants from the Bipolar and Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study included probands with schizophrenia (N=289), psychotic bipolar disorder (N=227), schizoaffective disorder (N=165), their first-degree relatives (N=315, N=259, N=193, respectively), and healthy controls (N=289). All were administered the WMS-III Spatial Span working memory test and the Brief Assessment of Cognition in Schizophrenia (BACS) battery. Results All proband groups displayed significant deficits for both forward and backward span compared to controls. However, after covarying for generalized cognitive impairments (BACS composite), all proband groups showed a 74% or greater effect size reduction with only schizoaffective probands showing residual backward span deficits compared to controls. Significant familiality was seen in schizophrenia and bipolar pedigrees. In relatives, both forward and backward span deficits were again attenuated after covarying BACS scores and residual backward span deficits were seen in relatives of schizophrenia patients. Conclusions Overall, both probands and relatives showed a similar pattern of robust working memory deficits that were largely attenuated when controlling for generalized cognitive deficits.
Publisher Summary This chapter describes a method of using electrochemistry in connection with energy conversion. Useful chemical energy may be defined as energy that can be released through exotermic chemical reactions. In general, chemical energy is associated with chemical bindings of electrons, atoms and molecules. The bindings may involve overlapping electron wavefunctions of two or more atoms, attraction between ionized atoms or molecules, and long-range electromagnetic fields created by the motion of charged particles. The organization of atoms or molecules in regular lattice structures represents another manifestation of chemical bindings. Some substances possess different crystalline forms, which may exist under given external conditions. In addition to the possibility of different solid phases, phase changes associated with transitions among solid, liquid and gas phases all represent different levels of latent energy. The salinity difference, such as the one existing between fresh (river) and saline (ocean) water, may be used to drive an osmotic pump, and the elevated water may in turn be used to generate electricity by an ordinary turbine. An alternative method, aiming directly at electricity production, takes advantage of the fact that the salts of saline water are ionized to a certain degree and thus may be used to derive an electrochemical cell. This electrochemical cell may be called a dialytic battery, since it is formally the same as the dialysis apparatus producing saline water with electric power input. In this case, the membrane allows one kind of ion to pass and thereby reach the corresponding electrode.
Sodium carboxymethyl cellulose-styrene butadiene rubber (CMC-SBR), sodium alginate (SA) and LA132 are utilized as the polymer binders for the cathodes of Li-S batteries to study their dispersion mechanism on the cathode materials and the consequent influence on the performance of Li-S batteries. Zeta potential tests, differential scanning calorimetry analysis and calculations of the rotational barriers of the links of the polymer chains by General Atomic and Molecular Electronic Structure System (GAMESS) reveal that higher charge densities and better chain flexibility of the binders promise the dispersion of the downsized cathode materials. LA132 is found to have optimal characteristic for dispersing and stabilizing the cathode materials in aqueous environment. The cycling performance and SEM images of the cathodes demonstrate that cathodes with higher dispersion degree achieve higher discharge capacities. The electrochemical impedance spectroscopy (EIS) results further support that better dispersed cathodes have lower impedance resulting from their well established conducting frameworks.
The bipolar nickel metal hydride batteries were fabricated with a novel anodic additive of nanometer copper oxide. Cycle voltammetry indicated that the nanometer copper oxide in the anode electrode was reduced to copper in the first charge, and SEM and EDS proved the sphere copper particles deposited on the alloy surface and stably existed in the next cycles. EIS results revealed the lower contact resistance and charge transfer resistance of the nanomaterial added anode electrode. Moreover, the bipolar battery with the nanometer additive displayed excellent electric performance and increased specific energy and power in electrochemical tests, which made it better meet the requirement of power sources for electric and hybrid vehicles. The present work has provided a novel additive of the anode electrode to effectively improve the performance of the bipolar Ni/MH batteries.
Na+ and Cl− co-doped LiFePO4/C composites were prepared via a simple solid state reaction. The structure, valence state and electrochemical performance were carefully investigated. Rietveld refinement on X-ray diffractions reveals that Na+ and Cl− have successfully been introduced into the lattice of LiFePO4. X-ray photoelectron spectroscopy proves that the co-doping of Na+ and Cl− does not change the chemical state of Fe(II). Experimental results further show that the co-doping contributes to induce the lattice distortion, modify the particle morphology, and increase the electronic conductivity. Considerably enhanced capacity, coulombic efficiency and rate capability were obtained in the co-doped LiFePO4. The specific capacities are 157mAhg−1 at 0.2C, 115mAhg−1 at 10C and 98mAhg−1 at 20C for the (Na+, Cl−) co-doped LiFePO4/C cathode material. The improvement can be ascribed to the enhanced electronic conductivity and electrode kinetics due to the micro-structural modification promoted by co-doping.
Public awareness of the need to reduce global warming and the significant increase in the prices of conventional energy sources have encouraged many countries to provide new energy policies that promote the renewable energy applications. Such renewable energy sources like wind, solar, hydro based energies, etc. are environment friendly and have potential to be more widely used. Combining these renewable energy sources with back-up units to form a hybrid system can provide a more economic, environment friendly and reliable supply of electricity in all load demand conditions compared to single-use of such systems. One of the most important issues in this type of hybrid system is to optimally size the hybrid system components as sufficient enough to meet all load requirements with possible minimum investment and operating costs. There are many studies about the optimization and sizing of hybrid renewable energy systems since the recent popular utilization of renewable energy sources. In this concept, this paper provides a detailed analysis of such optimum sizing approaches in the literature that can make significant contributions to wider renewable energy penetration by enhancing the system applicability in terms of economy.
This article examines the problem of quantifying lithium-ion battery state of charge (SOC) estimation errors. The article is motivated by the need for accurate SOC estimation in battery management and diagnostics applications. Given a statistical ensemble of SOC estimation experiments, one can classify these experiments’ estimation errors into an average bias plus estimation noise. Previous theoretical work by the authors quantifies both of these error types, and suggests that in the presence of reasonable voltage and current measurement uncertainties, bias effects are likely to dominate compared to noise. The main goal of this article is to extend this theoretical finding to a higher-order battery model, and furthermore validate it experimentally. In particular, the article shows experimentally that the SOC estimation errors for a LiFePO4 battery are much closer in magnitude to the SOC estimation bias predicted by our theoretical analyses. This is important not only because it furnishes an experimentally-supported analytic characterization of lithium-ion battery SOC estimation accuracy, but also because it contrasts to previous studies in the literature where SOC estimation accuracy is evaluated using the Cramér–Rao theorem, which assumes unbiased estimation.
A novel silicon/graphite material prepared by a new process, in which a gelatinous silicon precursor is deposited on porous natural graphite, is introduced. The obtained composite material provides an excellent cycling stability, high coulombic efficiencies and a good rate capability. Morphology and structure of the new material were examined by SEM/TEM measurements using focused ion beam technique for sample preparation.
Heavy metal tolerance of two marine strains of Yarrowia lipolytica was tested on solid yeast extract peptone dextrose agar plates. Based on minimum inhibitory concentration esteems, it is inferred that the two strains of Y. lipolytica were tolerant to heavy metals such as Pb(II), Cr(III), Zn(II), Cu(II), As(V), and Ni(II) ions. The impact of various heavy metal concentrations on the growth kinetics of Y. lipolytica was likewise assessed. With increased heavy metal concentration, the specific growth rate was reduced with delayed doubling time. Furthermore, biofilm development of both yeasts on the glass surfaces and in microtitre plates was assessed in presence of different heavy metals. In microtitre plates, a short lag phase of biofilm formation was noticed without the addition of heavy metals in yeast nitrogen base liquid media. A lag phase was extended over increasing metal concentrations of media. Heavy metals like Cr(VI), Cd(II), and As(V) are contrastingly influenced on biofilms’ formation of microtitre plates. Other heavy metals did not much influence on biofilms development. Thus, biofilm formation is a strategy of Y. lipolytica under stress of heavy metals has significance in bioremediation process for recovery of heavy metals from contaminated environment.
Electrochemical energy storage devices are currently an ideal tool to meet the energy needs of the people. It has been certified that niobium-based chalcogenides are generally used as the electrode materials for electrochemical energy storage devices due to their unique physical and chemical properties. This review summarizes the different synthesis methods and applications about the various niobium-based chalcogenides. In addition, in view of the existing problems of the niobium-based chalcogenides, many modification methods to improve the electrochemical properties of electrode materials are summarized, such as coating conductive matrixes, preparing composite materials, preparing porous or nanometer materials, and doping hetero atoms, etc. Finally, while summarizing the progress in recent years, the current bottlenecks and possible development directions in the future have also been proposed.
Over the past two decades, cerebral visual impairment has been recognized as a principal deficit in preterm children, and in particular those with cerebral palsy. We review the current knowledge of visual processing deficits in these children, and provide an overview of the tools for assessing cerebral visual impairment. Commercially available instruments are usually directed at evaluating visuospatial skills rather than detecting object recognition difficulties. Particularly in children aged 3 years or younger and in children with multiple handicaps, cerebral visual impairment is difficult to diagnose. This difficulty may be attributable to limitations specific to the instrument, such as a test that is inappropriate for age, or to child-specific limitations such as motor impairment or speech delay. We therefore include an overview of relevant neuroimaging findings reported in these children, focusing on the most recent imaging modalities. Novel techniques such as diffusion tensor imaging may provide sensitive markers of cerebral visual impairment in situations where clinical diagnosis is difficult, and such approaches may allow for early intervention.