batterydata/paper-abstracts huggingface dataset:
Cathode structure plays a vital role in lithium-air battery for that it can provide space for discharged products accommodation and free path for oxygen, e− and Li+ transport. However, pore blockage, cathode passivation and degradation all result in low discharge rates and poor cycling capability. To get rid of these predicaments, a novel highly conductive dual pore carbon aerogel based air cathode is fabricated to construct a lithium-air battery, which exhibits 18 to 525 cycles in the LiTFSI/sulfolane electrolyte at a current density varying from 1.00 mA cm−2 to 0.05 mA cm−2, accompanied by a high energy efficiency of 78.32%. We postulate that the essence lies in that the as-prepared air cathode inventively create a suitable tri-phase boundary reaction zone, facilitating oxygen and Li+ diffusion in two independant pore channels, thus realizing a relative higher discharge rate capability, lower pore blockage and cathode passivation. Further, pore structure, carbon loading, rate capability, discharge depth and the air's effect are exploited and coordinated, targeting for a high power and reversible lithium-air battery. Such nano-porous carbon aerogel air cathode of novel dual pore structure and material design is expected to be an attractive alternative for lithium-air batteries and other lithium based batteries.
The electrochemical performance of a carbon-based hybrid energy storage system, with Ce2(SO4)3/H2SO4 as inorganic redox electrolyte, was enhanced by optimizing several parameters of the device. A mass balance of the two electrodes forming the system together with the selection of a suitable activated carbon as negative electrode allowed the cell voltage to be increased up to 1.9 V. In addition, the use of a cation-exchange membrane significantly enhanced the electrochemical performance of the system by minimizing secondary reactions of cerium ions on the negative electrode. The optimized device reached energy and power density values up to ∼20 W h kg−1 and 524 W kg−1 respectively. Moreover, the system showed a good long-term electrochemical performance over 20,000 cycles.
Progressing limits on pollutant emissions oblige ship owners to reduce the environmental impact of their operations. Fuel cells may provide a suitable solution, since they are fuel efficient while they emit few hazardous compounds. Various choices can be made with regard to the type of fuel cell system and logistic fuel, and it is unclear which have the best prospects for maritime application. An overview of fuel cell types and fuel processing equipment is presented, and maritime fuel cell application is reviewed with regard to efficiency, gravimetric and volumetric density, dynamic behaviour, environmental impact, safety and economics. It is shown that low temperature fuel cells using liquefied hydrogen provide a compact solution for ships with a refuelling interval up to a tens of hours, but may result in total system sizes up to five times larger than high temperature fuel cells and more energy dense fuels for vessels with longer mission requirements. The expanding infrastructure of liquefied natural gas and development state of natural gas-fuelled fuel cell systems can facilitate the introduction of gaseous fuels and fuel cells on ships. Fuel cell combined cycles, hybridisation with auxiliary electricity storage systems and redundancy improvements are identified as topics for further study.
Free-standing and binder-free electrodes of carbon cloth uniformly covered with Cu2NiSnS4 nanospheres are synthesized via a facile surfactant-assisted hydrothermal method combined with post annealing treatment. The flexible composites are directly applied as electrodes for lithium ion batteries (LIBs) and sodium ion batteries (SIBs). The as-prepared electrodes display outstanding electrochemical performance. They deliver high reversible capacities of 1537 and 329 mAh g−1 after 150 cycles at a current density of 0.1 A g−1 for LIBs and SIBs, respectively. Even when the current density increases to 2 A g−1, the specific capacity remains at 1200 mAh g−1 for LIBs. Benefiting from the intrinsic nature of materials, structure features, and good electrochemical performance, the as-prepared flexible electrode can be utilized for flexible energy storage devices.
Metastable γ-MnS and stable α-MnS were synthesized via a one-step facile hydrothermal method and investigated as anode materials in Li-ion batteries and capacitors for revealing the essence of their electrochemical difference. Comparing with octahedrally coordinated [MnS6] in stable α-MnS, the Mn in γ-MnS has a tetrahedral coordination with smaller crystal field splitting and the Mn–S bond with a stronger covalent character, resulting in a lower discharge potential that enables assembled devices with a higher energy density. Density functional theory (DFT) calculation corroborates that the metastable γ-MnS possesses high charge density overlapping in the chemical bonds and decreased energy barriers for the reactive electrons deviating from 3d orbitals. Metastable γ-MnS delivers a larger storage capacity of 705 mAh g−1 at a current density of 100 mA g−1, and also demonstrates superior rate capability (362 mAh g−1 at 2 A g−1) and cycling stability (550 mAh g−1 remaining after 200 cycles at 0.5 A g−1) in Li-ion half cells. Moreover, the γ-MnS//AC hybrid capacitor with a wide voltage window of 0.1–4 V demonstrates a maximum energy and power density of 220 W h kg−1 and 10133 W kg−1 respectively, and cycles at 5 A g−1 without detectable capacity fading over 5000 cycles.
As a crucial material for fabrication of lithium-ion battery current collector, the properties of electrodeposited copper foil are closely related to the battery performances. How to improve its properties is thus of great importance for battery design and manufacturing. In this paper, we reported a novel composite additive, consisting of collagen, glycerol, hydroxyethyl cellulose, and sodium polydisulfide dipropane sulfonate, for electrodeposition of high-quality copper foil from conventional acid copper sulfate bath. Meanwhile, a pulse superimposed on direct current was used during the preparation process of copper foil. It was demonstrated that the additive could improve the foil’s performances, through changing the kinetic parameters of copper electrodeposition in sulfate bath. The optimized bath has a higher allowable current density during superimposed current electrodeposition, in contrast to the situation in direct current electrodeposition. This may then lead to an increase in deposition rate of copper foil, and a further improvement in surface roughness, grain size, residual stress, as well as elongation. Specially, the superimposed current offers a number of adjustable parameters for modulating copper foil’s properties in a wide range.
Several non-conventional electrolytes, molten salts, liquefied gas and supercritical fluids, are reviewed to show their usefulness and their possibilities in electrochemical applications. Special attention is paid to chemical and material production, material tailoring and energy conversion. In this work, molten salts are divided into high (T>473 K) and room (273 K≤T≤473 K) temperature salts. Characters and properties of representative molten salts are described for the corresponding temperature range. Some selected topics, mainly using molten halides, e.g. production of SiH4 gas, formation of metal nitrides, thermally regenerative fuel cells and thermogalvanic cells, are presented in the high temperature section. In the room temperature part, applications based on chloroaluminate melts such as AlCl3–EMIC melts are described, including electrodeposition of Al and Al alloys, Li batteries and capacitors. Finally, liquefied gas systems, such as NH3 and HCl, and supercritical fluids like supercritical water and CO2 are briefly mentioned as examples of new class non-conventional electrolytes.
Bowl-like hybrid structures have been designed and fabricated by anchoring NiO nanosheets on flat carbon hollow particles. When evaluated as an anode material for lithium-ion batteries, these unique NiO/carbon hybrid particles exhibit superior lithium storage properties in terms of high capacity, long term cycling stability and excellent rate capability.
Pitting corrosion of Pb in Na2CO3 solutions (pH=10.8) containing NaNO3 as a pitting corrosion agent has been studied using potentiodynamic anodic polarization, cyclic voltammetry and chronoamperometry techniques, complemented with scanning electron microscopy (SEM) examinations of the electrode surface. In the absence of NO3 −, the anodic voltammetric response exhibits three anodic peaks prior to oxygen evolution. The first anodic peak A1 corresponds to the formation of PbCO3 layer and soluble Pb2+ species in solution. The second anodic peak A2 is due to the formation of PbO beneath the carbonate layer. Peak A2 is followed by a wide passive region which extends up to the appearance of the third anodic peak A3. The later is related to the formation of PbO2. Addition of NO3 − to the carbonate solution stimulates the anodic dissolution through peaks A1 and A2 and breaks down the dual passive layer prior to peak A3. The breakdown potential decreases with an increase in nitrate concentration, temperature and electrode rotation rate, but increases with an increase in carbonate concentration and potential scan rate. Successive cycling leads to a progressive increase in breakdown potential. The current/time transients show that the incubation time for passivity breakdown decreases with increasing the applied anodic potential, nitrate concentration and temperature.
The increasing penetration of distributed energy resources in the distribution grid is producing an ever-heightening interest in the use of the flexibility on offer by said distributed resources as an enhancement for the distribution grid operator. This paper proposes an optimization problem which enables satisfaction of distribution system operator requests on flexibility. This is a decision-making problem for a new aggregator type called Smart Energy Service Provider (SESP) to schedule flexible energy resources. This aggregator operates a local electricity market with high penetration of distributed energy resources. The optimization operation problem of SESP is formulated as an MILP problem and its performance has been tested by means of the simulation of test cases in a local market. The novel problem has also been validated in a microgrid laboratory with emulated loads and generation units. The performed tests produced positive results and proved the effectiveness of the proposed solution.
An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50kW fluidised bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal+10% SRF) fuel mixture were found to be within the acceptable range and were generally lower than that obtained for coal+10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel.
Metals are energy-dense fuels that can react exothermically with water to produce hydrogen, and this hydrogen is useful as a propellant for rockets and underwater vehicles or as a fuel for engines and fuel cells. Propulsion systems usually rely on high-temperature combustion ( T > 3000 K) of metal-water propellants, while hydrogen-production systems typically employ low reactor temperatures ( T < 100 °C). This paper reviews the current state of knowledge of both low-temperature and high-temperature metal-water reactions. Low-temperature reactions allow only the chemical energy contained in the hydrogen to be used, with the thermal energy released during the metal-water reaction being wasted. Metal-water propulsion systems typically make use of only the thermal energy of the metal-water reaction, with the hydrogen being exhausted to produce thrust. This paper proposes several novel applications of high-temperature metal-water combustion that allow the full chemical energy within the metal fuel to be harnessed, including high-speed air-breathing engines and high-power, compact, low-emissions power-generation systems. These technologies promise improved performance by maximizing the conversion of the chemical energy, stored within the metal fuel, into useful work at sufficient rates for high-power applications.
ABSTRACT Harsh thermal conditions in the engine compartment pose challenges for many OEMs for granting long lifetime of batteries. With the raising spread of new battery technologies for several types of applications, many efforts are needed to grant stable heat distribution across cells. The paper investigates the modelling of heat distribution inside a common SLI-type battery using two different approaches (lumped-masse and solid conduction) and then analyzes the effects of a cost-effective, passive thermal insulator on such distribution. Designing a model that can handle in a simple and effective way different boundary conditions is key to be able to analyze in a quick way the impact of several possible battery-pack designs both for current and future on-vehicle applications.
The mesoporous α-Fe2O3/CaCO3 nanoparticles have been prepared from the mixture of Fe/Ca-hydroxides and ethylene glycol via a facile solvothermal method followed by sintering at 500 °C in air atmosphere. When used as anode materials for lithium-ion batteries, the mesoporous α-Fe2O3/CaCO3 nanoparticles show great cycling stability, excellent rate capability and improved specific capacity, which can be ascribed to the strong synergistic effect of the nanocomposite, the unique mesoporous structure and the pseudocapacitive contribution.
Next-generation left ventricular assist devices such as the HeartMate II (Thoratec Corporation, Pleasanton, CA) have significantly improved patient outcomes. In particular, the incidence of thromboembolic events appears to be significantly reduced. Pump thrombosis has occurred, however, and is well reported in the literature. The thromboses reported with next-generation devices have generally been partial thromboses associated with significant abnormalities in the system performance data as displayed on the system monitor. We describe a case of complete thrombosis of a HeartMate II axial-flow pump resulting in cardiac arrest but in the absence of alarms or significant aberrations in the performance data.
A semianalytical methodology based on the integral transform technique is proposed to solve the diffusion equation with concentration dependent diffusion coefficient in a spherical intercalation electrode particle. The method makes use of an integral transform pair to transform the nonlinear partial differential equation into a set of ordinary differential equations, which is solved with less computational efforts. A general solution procedure is presented and two illustrative examples are used to demonstrate the usefulness of this method for modeling of diffusion process in lithium ion battery electrode. The solutions obtained using the method presented in this study are compared to the numerical solutions.
P2-type Na2/3Fe1/3Mn2/3O2 was prepared by means of solid-state reaction. Its electrochemical properties as a cathode for sodium-ion batteries were investigated in the 1.5–4.3 V range vs. Na metal. This material delivers an initial discharge capacity as high as 193 mAh/g and maintains 153 mAh/g in 40 cycles. Such a high reversible capacity is achieved because both Mn3+/Mn4+ and Fe3+/Fe4+ become active in the studied voltage range, as confirmed by X-ray absorption spectroscopy (XAS). The thermal stability of charged cathodes was investigated by differential scanning calorimetry (DSC). Although the total heat generated by the fully charged Na0.25Fe1/3Mn2/3O2 is larger than that of the Li0.5CoO2 used as a reference, it is remarkably stable up to ca. 320 °C.
Three-dimensional (3D) macroporous silicon with stable interconnected structure is prepared by magnesiothermic reduction based on deliberate design, while flexible morphological control of zero-dimensional (0D) hollow nanospheres is realized via simply altering the conditions of the same reaction. When used as anode materials in lithium-ion batteries, the empty space in both structures allows for effective accommodation of large volume changes during lithium insertion and extraction. Due to the robustness of the interconnected porous structure, the 3D Si@C electrode exhibits better electrochemical properties with a reversible capacity of 1058 mAh g−1 after 800 cycles and 91% capacity retention (only 0.012% capacity degradation per cycle). The coulombic efficiency of the 3D porous electrode stabilizes at 99.4% in later cycles. The results demonstrated herein provide a better understanding of the controllable magnesiothermic reduction reaction, which is potentially an efficient method for large scale synthesis of high-performance Si anodes.
A novel hierarchically structured and highly hydrophilic poly(vinyl alcohol-co-ethylene)/poly(ethylene terephthalate) nanoporous separator (referred to NFs/PET/NFs) composed of a poly(ethylene terephthalate) (PET) nonwoven sandwiched between two interconnected poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofibrous membranes is successfully developed for lithium-ion battery. Systematical investigations including structural characterization, porosity measurement, water contact angle testing, electrolyte uptake, and thermal shrinkage testing demonstrate that the notable feature of this NFs/PET/NFs nanofibrous separator is an electrolyte-philic, highly porous and hierarchically nanoscaled structure, thus resulting in superior electrolyte wettability, lower thermal shrinkage, and higher ion conductivity, in comparison to the commercial Polypropylene (PP) separator. These structural characteristics enable the NFs/PET/NFs separator to offer an excellent cell performance including outstanding C-rate capability, high capacity and excellent cycling performance. This suggests that the NFs/PET/NFs separator is a promising material for practical application in lithium-ion battery due to it low cost production and high performance.
The objective of this study was to investigate the pattern of enzymatic activities, environmental genotoxicity and cytotoxicity in flounder, Platichthys flesus, from the Polish coastal area of the Baltic Sea. Fish were sampled in different contaminated sites in the Gulf of Gdansk and in a reference area outside the gulf. The activities of acetylcholinesterase (AChE), glutathione
National screening programs have reduced cervical cancer mortality; however participation in these programs varies according to women's personal and social characteristics. Research into these inequalities has been limited by reliance on self-reported service use data that is potentially biased, or administrative data that lacks personal detail. We address these limitations and extend existing research by examining rates and correlates of cervical screening in a large epidemiological survey with linked administrative data.
The calendar aging of commercial 18650 lithium-ion batteries with lithium nickel manganese cobalt oxide cathode and graphite anode is studied by regular electrochemical characterization of batteries stored at defined conditions. The cell capacity is found to decrease linearly with time and shows a faster decrease at higher storage temperatures. From current pulse tests, it is determined that both higher temperature and higher state of charge (SOC) cause accelerated resistance increase with storage time. Changes in different battery parameters during storage are also quantified by analyzing electrochemical impedance spectroscopy (EIS) spectra. The cell degradation causes a gradual increase of the ohmic and the total polarization resistance with storage duration, where the latter one is found to be the main contributor to the increased cell impedance. An increase in the mean relaxation time constant and changes in the porous structure for the electrode processes are observed from EIS analysis. Resistance for this cell chemistry is found to be current independent by comparing the cell resistance calculated from the current pulse method after 1s and from the EIS analysis at 1 Hz. Furthermore, it is seen that the additional charge throughput due to the periodic electrochemical characterization induces significant cell degradation effects.
Beyond the core symptoms of autism spectrum disorder (ASD), associated symptoms of anxiety can cause substantial impairment for individuals affected by ASD and those who care for them.
The structure, crystallinity, thermal properties, kinetic analysis of thermal degradation and ionic conductivity of poly(ethylene oxide)/lithium montmorillonite (PEO/LiMMT) nanocomposites prepared by melt intercalation were investigated. An intercalated structure of PEO/LiMMT nanocomposites was found by small angle X-ray scattering (SAXS). Differential scanning calorimetry (DSC) shows that an addition of LiMMT decreases the crystallinity of PEO which completely disappears above 80wt.% of LiMMT and decreases PEO melting temperature. The influence of LiMMT on the PEO crystallinity was also observed by SAXS and Fourier Transform Infrared Spectroscopy (FTIR). Thermogravimetric analysis (TGA) indicates that LiMMT significantly lowers the thermal stability of PEO and changes its degradation mechanism what is confirmed by kinetic analysis using isoconversional method and deconvolution procedure. Electrochemical impedance spectroscopy reveals the significant increase in ionic conductivity at room temperature with addition of LiMMT and optimum LiMMT content concerning conductivity was defined.
Micrometre-sized mesoporous materials have characteristic grains as well as pores nearly in the same scale. Electrodes of mesoporous materials for lithium batteries have short transport lengths for Li+ ions due to their nano-sized grains (10–20 nm), and easy access for electrolytes due to their nanopores (5–10 nm). Such mesoporous materials have high packing densities unlike nanopowders, nanowires, nanorods and nanotubes. Despite such advantages, electronic conduction over micrometre-sized particles limits the rate performance of mesporous materials. Occasionally counductive thin layers (2–5 nm) of carbon or RuO2 have been used to overcome such kinetic limitations and to achieve high storage performances. In this manuscript, we present a simple approach for the synthesis of mesoporous TiO2 anatase using a soft-template method, which shows superior storage performance without such conductive surface layers. Various cationic surfactants with different chain lengths have been selected for this investigation to assist the formation of the mesoporous TiO2 structure. Among these, cetyl trimethylammoniumbromide templated C16-TiO2 has the highest surface area of 135 m2 g−1 and reversible capacity of 288, 220, 138,134 and 107 mAh g−1 at 0.2, 1, 5, 10 and 30C respectively. The storage performance of the as-synthesized mesoporous TiO2 is nearly five times better than the commercially available TiO2 nanopowder. The packing density of meso-TiO2 is found to be 6.6 times higher than the TiO2 nanopowder. In addition, battery testing using mesoporous TiO2 electrodes without the 15% carbon additive exhibits nearly the same performance at low rate as the meso-TiO2 with carbon additives. These exciting results suggest a facile conduction path for electrons, a unique character of micrometre-sized mesoporous TiO2 with highly interconnected nanograins of 15–20 nm.