batterydata/paper-abstracts huggingface dataset:
Elastic and electrical conductive sponges are attracting materials for energy storage and energy harvest devices. In this study, we have demonstrated that a flexible and durable Cu doped PDMS sponge (Cu) can be adopted as electrodes for triboelectric nanogenerators (TENG) and flexible supercapacitors (SC). The Cu sponge loading with polypyrrole (PPy) was newly applied as single-electrode TENG for the first time. The outputs of the TENG were tuned by varying the PPy content or by combining with PDMS sponge. Due to the feasibility of changing the PPy content in the Cu@PPy sponges, this study offers a facile way to enhance the performance of TENG from the material itself with a tunable manner. Moreover, this study potentiates a better understanding of the triboelectricity produced by the TENG from the view of materials. The Cu@PPy sponges were further utilized as electrodes for all solid-state symmetrical SCs, in which the Cu sponge and PPy showed a synergistic effect on promoting the stability and performance of the SC. The SC exhibits lightweight, good capacitance, high flexibility, excellent mechanical and long-term stability, which is suitable for wearable energy storage devices. For the application of the TENG and the SC, a self-powered hybrid device was assembled, which provides a prospect for integrated devices. As a summary, we reported a new metal sponge based TENG and self-powered hybrid device, which demonstrated our study provides new opportunities for elastic multifunctional power sources and potential applications in wearable electronics.
Until now, dynamic fracture of materials—the fragmentation of a material because of stress, such as during impact—has only been observed using bulk-scale techniques, such as measuring fragment speeds or forensically examining samples. Dynamic fracture at the atomic scale could only be studied using computer simulations, because the size range that could be observed in materials by experimental techniques was too narrow. However, this has changed with a new technique reported by an Osaka University-led team for directly observing dynamic fracture in metals.
Pitch-based carbon foams prepared by a template method were used as negative current collectors to assemble flooded lead acid batteries, and the effect of the current collectors on the performance of the negative electrodes was investigated. Comparative galvanostatic charge–discharge tests show that the utilization efficiencies of the active material on the carbon foam negative current collector are 14% and 30% higher than those of the material on a lead grid one at 20 and 10 h discharge rates, respectively. Further EIS tests imply that there are also significant differences in the impedance spectra between the two electrodes. SEM images reveal that at the fully charged state, the particle size of the active material formed on the carbon foam current collector is much more uniform than that on the lead grid.
The authors regret that they did not discuss the too high charge/discharge capacities of LFP at low C-rate (Fig. 9) as these at ca. 185mAhg−1 exceed the theoretical capacity of 170mAhg−1. This is possibly caused by erroneous electrode weighing: as the mass loading is small, a slight underestimate could lead to a higher than real capacity.
The insertion of guest species in graphite is the key feature utilized in applications ranging from energy storage and liquid purification to the synthesis of graphene. Recently, it was discovered that solvated-Na-ion intercalation can occur in graphite even though the insertion of Na ions alone is thermodynamically impossible; this phenomenon enables graphite to function as a promising anode for Na-ion batteries. In an effort to understand this unusual behavior, we investigate the solvated-Na-ion intercalation mechanism using in operando X-ray diffraction analysis, electrochemical titration, real-time optical observation, and density functional theory (DFT) calculations. The ultrafast intercalation is demonstrated in real time using millimeter-sized highly ordered pyrolytic graphite, in which instantaneous insertion of solvated-Na-ions occurs (in less than 2 s). The formation of various stagings with solvated-Na-ions in graphite is observed and precisely quantified for the first time. The atomistic configuration of the solvated-Na-ions in graphite is proposed based on the experimental results and DFT calculations. The correlation between the properties of various solvents and the Na ion co-intercalation further suggests a strategy to tune the electrochemical performance of graphite electrodes in Na rechargeable batteries.
Molybdenum disulfide nanocrystals exhibit direct dependencies of the Raman peaks' intensities and their positions on the thicknesses of the nanocrystals. This indicates dependencies of the electronic structure on the thickness of the flakes, which scatter differently various laser wavelengths (473nm, 532nm and 633nm). Pulsed cathodoluminescence spectra of MoS2 nanocrystals under the action of high-energy electron pulse show an increase in the luminescence intensities with the increasing input of electron energy densities, where higher electron densities induce greater amount of electron-holes, which afterwards recombining release the energy in the form of luminescence. Irradiation of nanocrystals at maximum electron energy density of 200mJcm−2 leads to a strong luminescence band at 655nm (1.88eV), which is explained by recombination of A exciton. The luminescence decay kinetics of the nanocrystals under the action of different electron energy densities is presented.
This paper presents the results of the investigations of the thermal behavior of a model valve-regulated lead-acid cell at overcharge and saturation level around 90%. The heat capacity and the heat transfer coefficient are experimentally obtained. The quasi-steady state characteristics of the cell at constant charging current are measured. The experimental data show that, when operating in recombination regime, the stationary cell temperature is a linear function of the charging current. When the cell is gassing, part of the heat is dissipated with the released gases, as a result of which the cell temperature is lower than predicted from the linear temperature/current dependence. Introduced dimensionless slope of the temperature/current dependence is a characteristic of the VRLA battery, which could be used for fast and easy estimation of the temperature increase of the battery. The kinetic parameters of the oxygen evolution reaction (OER) proceeding at the positive plates of VRLA cells are experimentally determined. The current/overpotential dependence of the OER obeys the Tafel relation. The temperature/current dependence and the kinetics of the OER are used to estimate the critical charging voltage for safe operation of the battery.
In response to the severe blocks of the large volume change and sluggish capacity decay originating from the Lithium ion insertion/extraction in the anodes of Lithium ion batteries, transition metal oxides with high cycle stability are desirable yet extremely challenging for achieving high energy density anodes. Here, we report that a double-shelled NiO nanocrystal-doped MnO layer with robust defects, epitaxially grown on a nanoporous Ni network by simultaneously dealloying and oxidising NiMn alloy, can overcome these challenges to deliver a large capacity with excellent cycle stability. The interconnected core-shell nanoporous structure with robust defects possesses ultrahigh efficient electron/ion transport and a volume buffer. Consequently, the free-standing electrode as a whole delivers a highly reversible capacity of 1172 mAh cm−3 (960 mAh g−1) with a remarkable cycle life (105% retention after 200 cycles at 100 mA g−1). Furthermore, the electrode achieves a high capacity of 831.5 mAh cm−3 (681 mAh g−1) even at 1000 mA g−1, demonstrating a high rate capability. The proposed synthetic strategy can be further explored for the construction of other three-dimensional metal@metal oxide electrodes for application in next-generation energy storage systems.
The study aims analyzing if improved opacity in modern high-viscosity bulk-fill resin composites (BF-RBC) contradicts with the sufficiency of curing and to assess material’s tolerance to less ideal curing conditions.
Lithium metal has attracted much attention as an anode material for high-performance batteries owing to its high specific capacity and electrode potential. However, the Li metal electrode could suffer from the dendritic growth of Li during the cell operation due to the high reactivity of Li with organic electrolytes. To address this issue, we propose the use of thiourea as an electrolyte additive for Li metal-based batteries. The thiourea additive in LiTFSI/TEGDME electrolyte allowed the formation of a stable and uniform solid electrolyte interface layer on the Li electrode, thereby aiding the suppression of dendritic growth of Li and further electrolyte decomposition. Accordingly, a Li symmetric cell containing the thiourea additive exhibited six-times longer cycle life than a cell without the additive. Further, the electrolyte additive was also successfully employed in a Li-O2 cell to improve its cyclability.
In this paper we investigate the location-specific attractiveness of small wind turbines (SWT) for private households. In order to assess the economic viability of an investment in SWT, we analyze a set of scenarios that incorporate different types of SWT, various storage system options, support schemes, and specific urban surroundings for the case of Germany. As urban structures substantially influence local wind speeds, and hence the potential energy yield of a turbine, the location of SWT in the urban area is crucial for their economic feasibility. We find that SWT today are only profitable under very favorable conditions, the most important parameters being prevailing wind speeds and the location's degree of urbanization. In most cases, the coupling of the SWT to a storage system is crucial for cost-effectiveness. A feed-in tariff system specifically adapted to SWT technology is found to be an important driver of diffusion. Further research needs are identified in the field of long-term performance and yield projections for SWT. Based on the findings from our study, significant SWT diffusion can only be expected, if at all, in coastal suburban and rural areas.
DL-malic acid and L-aspartic acid are investigated as additives for the negative electrolyte of vanadium redox flow battery (VFRB) to improve its stability and electrochemical performance. The stability experiments indicate that the addition of L-aspartic acid into the 2MV(III) electrolyte can stabilize the electrolyte by delaying its precipitation. The results of cyclic voltammetry and electrochemical impedance spectroscopy show that the V(III) electrolyte with both additives demonstrates enhanced electrochemical activity and reversibility. The introduction of DL-malic acid and L-aspartic acid can increase the diffusion coefficient of V(III) species and facilitate the charge transfer of V(III)/V(II) redox reaction. Between the two additives, the effect of L-aspartic acid is more remarkable. Moreover, the VFRB cell employing negative electrolyte with L-aspartic acid exhibits excellent cycling stability and achieves higher average energy efficiency (76.4%) compared to the pristine cell (73.8%). The comparison results with the cell employing L-aspartic acid pre-treated electrode confirm that L-aspartic acid in the electrolyte can modify the electrode by constantly providing oxygen- and nitrogen-containing groups, leading to the enhancement of electrochemical performance.
Three artificial mixtures of PbSO4 and PbO2 as well as the active materials obtained directly from the positive plates of spent batteries have been solvothermally treated in methanol at 140 °C for 24 h, which produce mainly PbO·PbSO4. The PbO·PbSO4 can be easily desulphated with ammonium carbonate to produce PbCO3, which can be calcined to form α-PbO to be used as positive active material of lead acid batteries. The α-PbO powders are irregular particles and highly electrochemically active, which discharges around 165 mAh g−1 at 5 mA g−1, 80 mAh g−1 at 200 mA g−1 and 60 mAh g−1 at 400 mA g−1 with excellent cyclic stability in 50 cycles. SEM investigations show that the as-formed PbO·PbSO4 may inherit and enhance the morphological characteristics of PbSO4, and carbonation of PbO·PbSO4 does not destroy the rod-like characteristics. For the active material from the positive plates of spent lead acid batteries, the discharge capacities are 170 mAh g−1 at the current density of 5 mA g−1, and 60 mAh g−1 at 400 mA g−1, which is also similar. In 50 cycles, its capacity loss is only 5%.
Research suggests that a sense of belonging is a critical prerequisite of happiness and well-being. While some have focused on belonging provided by relationships, other work demonstrates the value of belonging in certain places. In the current research we join these efforts to understand belonging by offering a novel framework for exploring an understudied but no less fundamental aspect of human experience—time. We situate this framework within an existential analysis of human action and test general predictions about the psychological value of experiencing a sense of belonging in time, what we call temporal rootedness. Two samples (Studies 1 and 2) collected across cultures provide converging evidence that temporal rootedness is a unique psychological phenomenon that is predictive of personal psychological well-being. Two additional experiments (Studies 3 and 4) offer promising evidence that temporal rootedness can be situationally induced and threatened with consequences for well-being. These findings demonstrate the potential value of further exploration into this sense of belonging.
A type of hybrid energy harvester made of magnetic particles (MP-HG) which operates on both triboelectric and electromagnetic induction had been fabricated and reported. A triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) collectively generate electrical energy upon the same vibration motion of particles under both vertical and lateral vibrating directions. The electrostatic induction between the polymer and the particles enables the generation of the triboelectric component, and at the same time, the movement of particles through the coil activates the electromagnetic component upon the same particles motion. The device generates a maximum rectified output of ~3 V/16 μA under hybrid combination upon vertical vibration. The TENG component generates the maximum rectified output of ~2.2 V/300 nA with an instantaneous power density of ≈0.4 mW/m2 under a load resistance of 300 MΩ. The device is capable of generating electrical signals upon the vibrations produced from day-to-day electrical components such as compressor motor and speaker. Finally, MP-HG device was used to demonstrate the real-time application of zero power consuming/self-powered seismic detectors. Upon the vibration, the device can send the trigger signal to the Arduino board for driving the LED and buzzer. This type of devices can be used to alert/warn people from natural calamities like an earthquake which can cause severe causalities to the people and their belongings.
Sn with high theoretical specific capacity has suffered from poor cycling stability due to its huge volume changes during charging/discharging processes. In this work, a novel structure of tin nanoparticles well dispersed in ternary manganese-nickel-cobalt carbonate Mn0.54 Ni0.13 Co0.13 (CO3)0.8 (MNCCO3) is synthesized using a facile one-step solvothermal process and demonstrates significantly improved electrochemical performance compared to Sn nanoparticles or bare MNCCO3. Additionally, Sn content can be optimized to maximize the battery performance of the composite. When tested as an anode material in lithium ion batteries, the composite with 10wt.% Sn nanoparticles dispersed in MNCCO3 matrix (10Sn@MNCCO3) demonstrates the best performance, delivering a high initial charge capacity of 929mAh/g and retains a specific capacity of 657mAh/g after 50 cycles and 560 mAh/g after 100 cycles at a specific current of 100mA/g. The charge capacity of 10Sn@MNCCO3 decreases from a value of 991mAh/g when cycled at 50mA/g to 64mAh/g at 2000mA/g with the increasing specific current. When the specific current returns from 2000mA/g to 50mA/g, 10Sn@MNCCO3 retains a high capacity of 791mAh/g. The improved electrochemical performance can be ascribed to the synergic effect of both components in the composite, in which ternary carbonate MNCCO3 matrix not only provides high practical capacity, but also effectively accommodates the strain of dramatic volume change during long cycling, meanwhile Sn ensures a good electrical contact of the overall electrode due to its high electronic conductivity.
Up to now, there have been few studies in the annual fluxes of greenhouse gases in lakes of subtropical regions. The fluxes of methane (CH4) and carbon dioxide (CO2) across air–water interface were measured in a shallow, hypereutrophic, subtropical Lake Donghu (China) over a year cycle, using a static chamber technique. During the year, Lake Donghu emitted CH4 and CO2; the average flux of CH4 and CO2 was 23.3±18.6 and 332.3±160.1mgm−2 d−1, respectively. The fluxes of CH4 and CO2 showed strong seasonal dynamics: CH4 emission rate was highest in summer, remaining low in other seasons, whereas CO2 was adsorbed from the atmosphere in spring and summer, but exhibited a large emission in winter. Annual carbon (C) budget across air–water interface in Lake Donghu was estimated to be 7.52±4.07×108 g. CH4 emission was correlated positively with net primary production (NPP) and temperature, whereas CO2 flux correlated negatively with NPP and temperature; however, there were no significant relationships between the fluxes of CH4 and CO2 and dissolved organic carbon, a significant difference from boreal lakes, indicating that phytoplankton rather than allochthonous matter regulated C dynamics across air–water interface of subtropical lake enriched nutrient content.
To date, cognitive intervention research has provided mixed but nevertheless promising evidence with respect to the effects of cognitive training on untrained tasks (transfer). However, the mechanisms behind learning, training effects and their predictors are not fully understood. Moreover, individual differences, which may constitute an important factor impacting training outcome, are usually neglected. We suggest investigating individual training performance across training sessions in order to gain finer-grained knowledge of training gains, on the one hand, and assessing the potential impact of predictors such as age and fluid intelligence on learning rate, on the other hand. To this aim, we propose to model individual learning curves to examine the intra-individual change in training as well as inter-individual differences in intra-individual change. We recommend introducing a latent growth curve model (LGCM) analysis, a method frequently applied to learning data but rarely used in cognitive training research. Such advanced analyses of the training phase allow identifying factors to be respected when designing effective tailor-made training interventions. To illustrate the proposed approach, a LGCM analysis using data of a 10-day working memory training study in younger and older adults is reported.
Functionalized siloxane-based solid polymer electrolytes were synthesized using a platinum-catalyzed silylation reaction. The ionic conductivities of these solid polymer electrolytes were measured as a function of the concentration of lithium bis(trifluoromethylsulfonyl)imide (LiTFSi) salt. The highest ionic conductivity and lowest activation energy of solid polymer electrolytes were observed to be 1.15 × 10−4 S cm−1 (25 °C) and 3.85 kJ mol−1, respectively. The interface property between electrolyte and electrode and thermal stability of the polymer electrolytes were found to enhance after they were functionalized with acrylate, and the functionalized electrolytes were observed to maintain a glass transition temperature as low as that of other siloxane compounds. Thus, modifications involving acrylate with ethylene oxide group substitution provide a route for carrier ions and enhance both the ionic conductivity and mechanical properties of the siloxane structure.
Many efforts have been paid to realize the superior anodes for future Li batteries in either the dry Ar atmosphere or the dry air atmosphere. In this work, in order to clarify the effects of such atmospheres, the most reactive anodes of Li were freshly electrodeposited under the dry Ar or under the dry air condition. The Solid Electrolyte Interface (SEI) formed during the electrodeposition of Li anodes is revealed to have a different chemical composition and protective feature. The Li deposited under the dry air was revealed to have longer cycle life in the electrolyte than that deposited in Ar, even in the electrolyte containing ionic liquid. From the XPS results, the SEI formed in dry air is proved to be different from that formed in Ar gas atmospheres, that is, the SEI formed in dry air consists of Li2CO3 and Li nitride. In order to improve the performance of the anodes, the atmosphere for the initial preparation of the anode/electrolyte interface should be tuned.
Background Workers are vulnerable to heat stress when they perform tasks in hot environments. Personal cooling systems (PCSs) are designed to reduce heat strain. A cooling vest with ventilation fans is a type of PCS that can blow air around the body to facilitate convective and evaporative cooling. Objective This study aims to evaluate the performance of a ventilation unit for a tailor-made cooling vest designed to protect construction workers from heat stress. The performance of this newly designed ventilation unit (Unit B) was compared with that of the ventilation unit used in a commercially available cooling vest (Unit A). Method The designed ventilation unit consists of a pair of ventilation fans and a portable battery pack. A hot wire anemometer was used to measure the air flow rate of the fan. The air flow rate and work duration of different ventilation units were compared. The sweating manikin test was conducted to further compare the cooling powers of the ventilation units. Result Compared with Unit A powered by the alkaline AA battery (6 V, 2122 mAh), Unit B powered by the rechargeable lithium-polymer (Li-Po) battery (7.4 V, 4400 mAh) achieved a higher air flow rate (8–22 L/s vs. 0–13 L/s) and longer work duration (7.05 h vs. 6.22 h). The average cooling power of Unit B on the sweating manikin was 68 W, which was higher than that of Unit A (51 W). Practical applications Results showed that the newly designed ventilation unit exhibited higher air flow rate and cooling power. The ventilation unit designed in this study will be incorporated into a tailor-made PCS for protecting workers in the heat.
Nanostructured nickel hydroxide electrode is fabricated directly by electrophoretic deposition (EPD) method. After annealing at 300°C for 3h, nickel hydroxide nanoplatelet converts into nickel oxide. EPD method is useful in depositing nickel hydroxide nanoplatelets from isopropyl alcohol suspension containing iodine and water additives. Hydrogen ions are generated by the reaction between iodine and water and then adsorbed on the nickel hydroxide, resulting in positively charged nickel hydroxide. Positively charged nanoplatelet of high zeta potential is beneficial to EPD and dispersion. An electrode deposited by EPD has better uniformity than one deposited by dip coating. Electrochemical performance of the electrodes is investigated by cyclic voltammetry in 0.5M KOH. Specific capacitance of the nickel oxide electrode prepared by EPD is higher than that of prepared by dip coating even at a very high rate of 500mVs−1. In addition, an electrode prepared by EPD also shows excellent cycle-life stability because its specific capacitance decreases only slightly after 5000 charging/discharging cycles.