batterydata/paper-abstracts huggingface dataset:
A novel hybrid material of carbon-coated Si nanoparticles (NPs) encapsulated in 3D graphene network (C-Si@G) was facilely synthesized by the assembly of graphene oxide-encapsulated Si NPs followed by a soldering treatment with carbon derived from polyvinylidene fluoride (PVDF) at a carbonization temperature. The amorphous carbon-coated Si NPs of ∼50 nm in diameter were completely wrapped in 3D conductive graphene network. As a negative electrode material of lithium-ion batteries (LIBs), C-Si@G nanocomposite delivered a superior Li-storage capacity of 2883.1 mAh g−1 under a constant rate of 0.1 A g−1. Meanwhile, a stable cycling performance with a specific capacity of ∼752 mAh g−1 was achieved after 270 cycles for C-Si@G nanocomposite at a rate of 5 A g−1. The superior electrochemical properties of C-Si@G with respect to the desirable capacity, reliable cyclic performance, and high rate ability were attributed to the significantly enhanced electrical conductivity by carbon coating and void space of 3D graphene to buffer the severe volume variation of Si NPs as well as enhanced charge transfer ability and promoted lithiation process of the anode.
Carbon/ZnCo2O4 nanoparticles’ hybrid highly dispersed within a carbon nanotube nest were synthesized by the carbonization of in situ formed MOF-74-ZnCo/CNT hybrid materials. Results demonstrated that the synthesized mixed transition metal oxides/carbon/CNT composite provided a stable energy density of 800 mAh g−1 at 100 mA g−1. It could also provide a reversible capacity of 430 mAh g−1 under a high current of 2000 mA g−1 even after 1000 cycles. The outstanding performances of C/ZnCo2O4@CNT can be accredited to the synergistic effects from the porous nanostructured bi-metal oxides, the carbon and the CNT nest. These properties can improve the conductance of the material, alleviate the stress on ZnCo2O4 nanoparticles through accommodating the volume variation during lithium exchange processes, and offer fast diffusion roads for ions and more active sites for lithium storage.
Bioinspired materials (BMs) are one of the most attractive candidates for various environmental applications. BMs are synthesized like as natural materials with many excellent properties. These BMs can be crystalline, flexible, and tunable porous, while maintaining chemical and thermal stability. BMs are used in high-pressure adsorption and catalytic applications (with possible key-lock bonding mechanisms). Through surface functionalization, they can also be employed in diverse areas such as drug delivery, diagnosis, and sensing. Likewise, recent progress in BMs, especially for carbon capture and storage (CCS) and energy applications, has been attributed to their superior function (e.g., artificial photosynthesis and cycloaddition) and their ability to provide useful final products (e.g., renewable energy). In this review, we evaluated the different types of BMs and their roles in CCS and energy applications. The discussion is extended further to cover diverse research interests in this emerging field.
Over the past few years, lithium sulfur (LiS) batteries have attracted growing attention as an enabling technology because of their high energy density. The limitations to commercialize LiS batteries originate from the intrinsic properties of sulfur: its poor electronic conductivity and the polysulfide shuttling effect. The aim of this research is to address these challenges by developing an additive for LiS batteries. Aluminum (Al) powders prepared from soda cans were mixed with sulfur to form a composite with a sulfur mass loading up to 90 wt%. The electrochemical performance shows that the AlS composite in LiS cells exhibits a stable retention after 200 cycles and an ability to stabilize quickly (<10 cycles). Moreover, the rate performance of the AlS composite is improved over conventional carbon additives. Post analysis suggests that AlS surface interaction is a possible origin for this improvement.
The emerging wearable and foldable electronic devices drive the development of flexible lithium ion batteries (LIBs). Carbon materials are considered as one of the most promising electrode materials for LIBs due to their light weight, low cost and good structural stability against repeated deformations. However, the specific capacity, rate capability and long-term cycling performance still need to be improved for their applications in next-generation LIBs. Herein, we report a facile approach for immobilizing phosphorus into a large-area carbon nanosheets/nanofibers interwoven free-standing paper for LIBs. As an anode material for LIBs, it shows high reversible capacity of 1100 mAh g−1 at a current density of 200 mA g−1, excellent rate capabilities (e.g., 200 mAh g−1 at 20,000 mA g−1). Even at a high current density of 1000 mA g−1, it still maintains a superior specific capacity of 607 mAh g−1 without obvious decay.
Neutrinos rotating around Abelian Higgs strings will generate a neutral current close to the string. As the string moves through the cosmic plasma, the velocity kick generated by the motion of the string will enhance the neutrino current in the wake region. The neutrino current density depends on its distance from the string and is oscillatory in nature. This leads to neutrino density gradients in the plasma. Such a flux of neutrinos with periodic density fluctuations will lead to electron currents in the plasma. The current will act like a cross-perturbation across the cosmic string wake. The perturbation as well as the high Reynolds number of the plasma will result in the generation of magnetic fields in the wake of the cosmic string.
The corpus callosum (CC) has been of interest in schizophrenia research because of its possible role in reduced lateralization and because of its sexually dimorphic characteristics. The literature has been replete with structural brain studies that have yielded equivocal results because of failure to address sex differences, handedness, and overall reductions in total brain volume (TBV) associated with schizophrenia. We performed midsagittal corpus callosum area MRI measurements on 71 chronically ill patients with schizophrenia (52 males, 19 females) and 67 controls (49 males, 18 females) using a semiautomated analytic technique subdividing the corpus callosum into five segments. Consistent with a meta-analysis [J. Neurol., Neurosurg. Psychiatry 58 (1995) 457], reductions in total CC area (after controlling for TBV and age) were found in schizophrenia patients relative to controls. However, our effect size, though not statistically significant, was −0.33 compared to −0.18 for the meta-analysis, indicating greater reductions in total CC area in our group of patients. Statistical significance was achieved only in male patients versus male controls (effect size=−0.50). The effect size remained the same when only right-handers were included in the analysis; thus, handedness did not account for this result. CC size was not related to psychiatric symptoms nor cognitive functioning in this group of patients.
Objetivo Obtener una versión española del Modified Stanford Health Assessment Questionaire (MSHAQ), así como evaluar su fiabilidad, consistencia interna y validez de constructo Diseño Adaptación según la metodología de traducción y retrotraducción centrada en garantizar la equivalencia conceptual de cada ítem. Para el estudio de validación se realizó un análisis transversal Participantes Un total de 52 personas mayores de 65 años controladas por alguna afección clínica crónica Mediciones principales Además de la anamnesis y el índice de Barthel, se pidió a los pacientes que contestaran la versión española del cuestionario MSHAQ el día de la visita y 3 días después para valorar la fiabilidad test-retest Resultados Se estudió una muestra de 52 individuos, 23 varones y 29 mujeres, con una edad media de 74,2 ± 5,8 años. El estudio de la fiabilidad test-retest muestra un coeficiente de correlación intraclase (CCI) de 0,89, 0,82, 0,88 y 0,51 para las tablas A (capacidad), B (satisfacción), C (necesidad de ayuda) y D (cambio en los últimos 6 meses) del MSHAQ. Estas cuatro subescalas presentan una consistencia interna con un valor alfa de Cronbach de 0,83, 0,76, 0,61 y 0,82, respectivamente. Se ha observado una correlación estadísticamente significativa entre todas las tablas del cuestionario y entre éstas y el índice de Barthel Conclusiones Se puede concluir que la versión española del MSHAQ es un instrumento de medida válido y fiable que permite la comparación de estudios realizados en distintos países
For high energy density and long cycle life of rechargeable lithium ion batteries, the positive electrode of LiNi0.6Co0.1Mn0.3O2 (NCM-613) is post-surface treated by poly(4-vinylphenol) (PVP) though a spin coating method. The additional PVP coating on the electrode is highly beneficial for improving the cycle life of the cell. It is also found that the PVP coating initially causes a polarization for lithium surface transportation but enhances the rate capability after long cycling by reducing the growth of polarization from the repeated sequences of charge and discharge. To adjust these conflicting behaviours, the coating condition of PVP should be optimized. By using a systematic analysis of X-ray diffraction and surface analyses of field emission scanning electron microscopy and X-ray photoelectron spectroscopy, it is concluded that the PVP surface coating on NCM-613 prevents crystal structure deterioration leading to irreversible structure changes from hexagonal to monoclinic at a high potential of 4.3V vs. Li/Li+.
We have reported in our past work that electrodeposited Sn–Ni alloy with different composition show considerably different performance as anode materials for Li-ion batteries, and the performance was remarkably well (ca. 650mAhg−1 at 70th cycle) when the composition was controlled to Sn62Ni38. In this work, structural changes during charge discharge cycling of Sn–Ni alloy with different composition were investigated to evaluate their differences in the cycle performance. From the XRD result, Ni3Sn4 phase was the main phase seen in Sn62Ni38, and its reversible reactivity with Li was confirmed. We suggest that this is the key phase for its high capacity and lengthened cycle life. From Sn54Ni46, which showed low capacity, only a metastable phase close to the structure of SnNi was confirmed. The results from Sn84Ni16 indicated the presence of pure Sn and Sn rich metastable phase would lead to relatively fast electrode degradation.
The crystal and electronic structures of LaNi4:75Sn0.25 intermetallics and LaNi4.5Sn0.5H y (y=2.0, 2.5) intermediate phase have been investigated by the full-potential linearized augmented plane wave (FP-LAPW) method. Hydrogen occupation sites in LaNi4.5Sn0.5H y have been determined based on Westlake's criterions: (1) the minimum hole radius is 0.04 nm; (2) the minimum H-H distance is 0.21 nm; as well as geometry optimizations and internal coordinates optimizations. We find that hydrogen atoms prefer to occupy the 12n*, 6m, 12o, 6m* sites in LaNi4.5Sn0.5H2.0 and the 6m*, 4h, 6m, 12o, 12n* sites in LaNi4.5Sn0.5H2.5. The specific coordinates of hydrogen atoms in LaNi4.5Sn0.5H y are also determined. The results show that hydrogen atoms tend to keep away from tin atoms. The maximum hydrogen content decreases compared with LaNi5. The interactions between Sn and Ni with H play a dominate role in the stability of LaNi4.5Sn0.5-H system. Lattice expansion and increment of Fermi energy E F show that both Sn and H atoms decrease structural stability of these alloys.
In order to investigate the effects of electrode density and thickness on the room temperature electrochemical performance of lithium metal polymer batteries (LMPBs), four LiFePO4 cathodes with different electrode density/thickness (1.6gcm−3/20μm, 1.6gcm−3/40μm, 2.0gcm−3/20μm, and 2.0gcm−3/40μm) are prepared. Several types of unit cells employing each cathode are prepared using in situ thermally cross-linked polymer electrolytes controlled under the same manufacturing condition. The unit cells employing the thinnest cathode with highest density achieve the most improved rate capability and cycle life, which seems to be attributed to the higher electrical conductivity of the cathode and shorter diffusion length of Li+ ions within the cathode pores. In addition, the LMPB with an optimized LiFePO4 cathode (2.0gcm−3, 20μm) and polymer electrolyte (5vol% of the crosslinking agent with non-volatile liquid electrolytes) delivers a high and stable charge/discharge capacity under very fast charging and discharging conditions (at a 2C rate) at room temperature.
In this work, we study the design aspects and process dynamics of solvent removal from Lithium-ion battery electrode coatings. For this, we use a continuum level mathematical model to describe the physical phenomenon of cathode drying involving coupled simultaneous heat and mass transfer with phase change. Our results indicate that around 90% of solvent is removed in less than half of the overall drying time. We study the effect of varying temperature and air velocity on the drying process. We show that the overall drying energy can be reduced by at least 50% by using a multi-zone drying process. Also, the peak solvent flux can be reduced by at least 40%. We further present the effect of using an aqueous solvent instead of N-Methyl-2-pyrrolidone (NMP) in electrode drying. Our results indicate that Water dries nearly 4.5 times faster as compared to NMP and requires nearly 10 times less overall drying energy per kg of solvent.
Self-powered flexible electronics are of particular interest and important for next generation electronics due to their light weight, flexible and self-sustainable properties. Many self-powered sensors made from piezoelectric composite materials are either inflexible or possess low piezoelectricity. In this work, we demonstrate self-powered flexible and highly active pressure and shear sensors based on freeze casting ceramic–polymer structures. A lamellar lead zirconate titanate (PZT) structure is initially developed via freeze-casting and the piezoelectric composites are formed by impregnating a polydimethylsiloxane (PDMS) matrix into the aligned pore channels. The structured PZT–PDMS composites exhibited a high effective longitudinal piezoelectric coefficient (d33*) of 750 pC N−1, which is higher than that of the monolithic ceramic due to the combination of bending and flexural effects. The use of freeze casting enables the manufacture of complex and arbitrary shaped 3D piezoelectric architectures, along with the unique advantages of low-cost and ease of fabrication. A 14 × 14 mm2 PZT–PDMS pressure sensor was able to bend to a small radius of 8 mm and maintain a high d33. Furthermore, the manufactured self-powered sensors are demonstrated in a range of applications, such as acceleration, strain and touch sensors that use the d33, d31 and d15 coefficients to detect longitudinal, transverse and shear loads. This work expands on the potential applications of freeze casting and provides new opportunities for the manufacture of future electronic sensors.
A novel solvent-free thermal reaction of ferrocene and sulfur is developed for preparing iron sulfide and carbon nanocomposites, where ferrocene acts as both iron and carbon source. The prepared composite has iron sulfide sandwiched in carbon matrix. Moreover, ferrocene and sulfur can turn to vapor phase at an elevated temperature, resulting in easy deposition of product on the surface of templates. Sodium chloride was selected as a template due to its nontoxic and water-soluble nature. The NaCl-templated composite shows “sphere on mattress” morphology and exhibits the highest capacity and the longest cyclability ever reported for iron pyrite anode. To obtain mesoporous nanocomposites, SBA-15 was also applied as templates. The mesoporous nanocomposite demonstrates excellent capacity retention capability, indicating the robust structural stability.
Fuel cells aboard hybrid electric vehicles (HEVs) are often hybridized with an energy storage system (ESS). Batteries and ultracapacitors are the most common technologies used in ESSs aboard HEVs. High-speed flywheels are an emerging technology with traits that have the potential to make them competitive with more established battery and ultracapacitor technologies in certain vehicular applications. This study compares high-speed flywheels, ultracapacitors, and batteries functioning as the ESS in a fuel cell based HEV on the bases of cost and fuel economy. In this study, computer models were built to simulate the powertrain of a fuel cell based HEV where high-speed flywheels, batteries, and ultracapacitors of a range of sizes were used as the ESS. A simulated vehicle with a powertrain using each of these technologies was run over two different drive cycles in order to see how the different ESSs performed under different driving patterns. The results showed that when cost and fuel economy were both considered, high-speed flywheels were competitive with batteries and ultracapacitors.
X-ray absorption fine structure spectroscopy and scanning electron microscopy were used to study the atomic short range order structure, surface morphology and thickness of cobalt films electrodeposited from CoCl2 solutions on gold-coated Kapton. While the morphology on the electrodeposits strongly depends on the deposition time and thereby on the film thickness, the short range order structure deduced from the X-ray spectroscopic experiments suggests that pure metal films were formed, however with a slight relaxation of the Co-Co bond distances with increasing thickness, which may open new routes for the preparation of nanostructured Co-materials.
Si thin-film electrodes were deposited by rf magnetron sputtering method, and stress variation during charge and discharge process was measured. When Si reacts with Li forming several alloy phases sequentially, large volume expansion occurs inducing compressive stress. On Li insertion to 0V, the formation of Li4.4Si phase, which have a volume three or four times larger than Si, causes a microcracking in the electrode, thereby the cycle performance is deteriorated. However, by limiting the lower cut-off voltage to 0.1V, the cyclability was improved significantly. This is attributed to the reduction of the crack formation due to volume expansion, as inferred from the stress variation profile.
We describe in this work the synthesis and the characterization of homogeneous, carbon-coated lithium titanium oxide micro spheres and demonstrate their use for the fabrication of an active negative electrode combined with a high surface area, activated carbon positive electrode to form an advanced non aqueous, hybrid supercapacitor. We show that this activated carbon/carbon coated-Li4Ti5O12 device retains 95% of its initial capacity after 1000 cycles with a maximum volumetric energy and power density of 57 Wh L−1 and 2600 W L−1, respectively. Due to this unique performance, the hybrid supercapacitor developed in this work is expected to be a very promising energy storage device suitable for applications that require high energy levels and fast charge and discharge cycles, such as those requested in the EV sector.
So-called Prussian Blue Analogues (PBAs) attract significant research interest for a large variety of electrochemical applications. Recently, they have been recognized as promising electrode materials to implement in aqueous Na-ion batteries for grid-scale energy storage systems. Further types of aqueous batteries using, for instance, alkali metal cations such as Li+ and K+ or multivalent ions like Mg2+, Zn2+ and Al3+ as insertion species for PBA-based electrodes are being explored. In this study we systematically investigate intercalation of Mg2+ into four electrodeposited PBA thin films: Na2Ni[Fe(CN)6], Na2Co[Fe(CN)6], Na2VOx[Fe(CN)6], and NaIn[Fe(CN)6]. All four electrodes are capable of hosting Mg2+, while NaIn[Fe(CN)6] shows better stability upon repeated (dis)charging compared to the other three systems. Surprisingly, even though the hydration energies of Na+ and Mg2+ differ significantly, the mean half-charge potentials of (de)intercalation are comparable for both cations. A correlation between the empirical radii of transition metals present in the structure of PBAs and the mean half-charge potential of (de)intercalation, previously identified for Na+, is also found for Mg2+.
The use of biomarkers as early-warning signals to assess the impact of pollutants and other environmental stressors in coastal habitats has been internationally recognized as a useful tool in marine coastal monitoring. We propose a similar approach to verify the welfare of edible shellfish, Ruditapes philippinarum, thus exploiting its possible application as an effective tool to verify the origin of fishing/aquaculture products. A selected battery of biomarkers was chosen and applied to organisms from two different habitats in the Lagoon of Venice (a farming site and a natural area where fishing is currently banned, because of pollution problems) and from a local market. Biological responses were evaluated physiologically (survival in air test and condition index), behaviourally (reburrowing rate), and histochemically (quantification of neutral lipids and lipofuscin). Micropollutants (heavy metals, PCBs, and PAHs) were also determined in the soft tissues. Results indicated clams from the farming site were in the best condition with regard to both chemical and biological measurements. In contrast, the market sample contained the highest concentrations of PAHs. PCBs and heavy metals varied slightly and quite irregularly among the three samples. The worst values of the biomarkers were observed for clams collected at the polluted site, where, in particular, the lowest physiological and behavioural indexes and the highest accumulation of lipofuscin in the digestive tissue were recorded.
The ability to synthesizing monodisperse Li4Ti5O12 (LTO) nanospheres is the key to reducing the irreversible capacity of LTO materials, and thus improving their power performance. However, it remains a grand challenge to achieve uniform precursors of LTO nanospheres and maintain their spherical structures after annealing. Herein, we develop a robust strategy for the synthesis of monodisperse LTO nanospheres with an average diameter of 120nm via the use of titanium nitride (TiN) as a titanium source for lithium ion batteries (LIBs). The precursors composed of uniform TiO2/Li+ nanospheres were formed in a stable alkaline environment during the course of heating of the solution of peroxo-titanium complex as a result of the dissolution of TiN, while TiO2/Li+ microspheres were easily yielded with the decrease in pH value of the precursor solution. The OH− anion was found to effectively retard the hydrolysis of peroxo-titanium complex as well as the aggregation of TiO2/Li+ nanoparticles. Intriguingly, a uniform polyvinyl pyrrolidone (PVP) layer formed in-situ on the surface of TiO2/Li+ nanospheres rendered LTO to retain the monodisperse spherical morphology after annealing. Notably, the as-prepared monodisperse LTO nanospheres comprised of the interconnected LTO nanograins with an average size of ~15nm uniformly coated by a carbon layer derived from the carbonization of PVP exhibited a high tap density (1.1gcm−3) and an outstanding rate-cycling capability. The charge specific capacities at 1, 10, 50 and 80C were 159.5, 151.1, 128.8 and 108.9mAh g−1, respectively. More importantly, the capacity retention after 500 cycles at 10C was as high as 92.6%. This work opens up an avenue to craft the uniform precursors of LTO and thus monodisperse LTO nanospheres that possess superior rate performance with high volumetric energy densities and long-term cyclic stability.