batterydata/paper-abstracts huggingface dataset:
Although the well-known anatase, one of the allotropic forms of natural TiO2, was recently proposed for lithium-ion battery electrodes, the material generally suffers from reduced cyclability and limited power, due to kinetic drawbacks and to its poor charge transport properties. Here, boron (B)-doping anatase TiO2 nanofibers were synthesized via a facile sol-gel method and the electrospinning method for use as anodes. The incorporation of B element not only promotes the crystallization of the building subunits of the microporous TiO2, but also improves the electrochemical performance at higher current rates and longer cycles. A capacity of 147mAhg−1 at a current density as high as 4Ag−1 and an excellent long-term cycling stability with a capacity retention of 167.6mAhg−1 at the current rate of 2Ag−1 over 5000cycles could be achieved when an appropriate amount of B was doped into TiO2 anodes. The reasons for the improvement of rate capability may be attributed to the enhancement of electronic conductivity, lithium ion diffusion kinetics, and the surface storage property for the B-doping anatase TiO2 anodes.
Chemical and electrochemical techniques are presented for the analysis of Fe(VI) compounds used in super-iron electrochemical storage cells. Fe(VI) analytical methodologies summarized are FTIR, ICP, titrimetric, UV/VIS, XRD Fe(VI), potentiometric, galvanostatic, cyclic voltammetry, and constant load, current or power electrochemical discharges probes. The investigated FTIR methodology becomes quantitative with introduction of an internal standard such as added barium sulfate. Electrochemical techniques which utilize a solid cathode, and spectroscopic techniques which utilize a solid sample, are preferred over solution phase techniques. The titrimetric methodology (chromite analysis) has been detailed, and adjusted to determine the extent of Fe(VI→III) oxidation power in both unmodified or coated Fe(VI) compounds. Fe(VI) compounds have also been variously referred to as ferrates or super-iron compounds, and include K2FeO4 and BaFeO4. Such compounds are highly oxidizing, and in the aqueous phase the full three electron cathodic charge capacity has been realized, as summarized by reactions such as: FeO4 2−+5/2H2O+3e−→1/2Fe2O3+5OH−.
The modified multi-walled carbon nanotubes (m-MWCNTs)/Ag composite catalyst (Ag/m-MWCNTs) is prepared successfully by a facile in situ growth method. The physicochemical properties of Ag/m-MWCNTs are characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements. The results demonstrate that the dispersed Ag nanoparticles are anchored on the surface of m-MWCNTs with a mean diameter about 10.6nm. The as-prepared Ag/m-MWCNTs catalyst shows high electrocatalytic activity toward the oxygen reduction reaction (ORR) in alkaline media. The ORR is dominated by four-electron pathway in the limiting diffusion zone, which is similar to the commercial Pt/C catalyst. The high catalytic activity of the Ag/m-MWCNTs can ascribe to the dispersed Ag nanoparticles on the m-MWCNTs which not only facilitate the ORR process, but also may promote the decomposition or further reduction of HO2 − formed at the surfaces of the MWCNTs.
In this study highly pure carbons synthesized using resorcinol furaldehyde catalyzed with hexamethylenetetramine (an amine base) are tested for supercapacitor electrodes. This synthesis is not only from all-organic renewable sources, but can also significantly increase the performance of the device by promoting adequate electric double layer formation. The electrochemical characterization shows an increase in the specific capacitance per unit of surface area that is 18% higher than that of commercial biomass carbons and their synthetic counterparts. The life of the capacitor is also extended to twice that of the commercial brand tested here and has increased power after cycling. The supercapacitors made from this synthesis have electric double layer characteristics as desired in some applications. The samples have been tested for composition using XPS, and their electrochemical performance was analyzed using galvanostatic measurements and complex capacitance and power derived from impedance spectroscopy.
Although previous research has associated the glycaemic load (GL) of a meal with cognitive functioning, typically the macro-nutrient composition of the meals has differed, raising a question as to whether the response was to GL or to the energy, nutrients or particular foods consumed. Therefore, the present study contrasted two breakfasts that offered identical levels of energy and macro-nutrients, although they differed in GL.
In the present study, the authors propose a new framework that integrates literature on achievement, supports the testing of novel hypotheses, and stresses the importance of examining a large number of factors in the same study. This framework assumes that high achievement is a function of three categories of factors: (a) opportunity factors (e.g., coursework), (b) propensity factors (e.g., prerequisite skills, motivation), and (c) distal factors (e.g., SES). A secondary analysis of the National Longitudinal Educational Study (NELS:88) using hierarchical regression and structural equation modeling revealed that 58–81% of the variance in achievement was explained by family variables and specific opportunity and propensity factors. The findings are discussed in terms of their potential implications for intervention efforts.
There are an increasing number of vehicle choices available that utilize batteries and electric motors to reduce tailpipe emissions and increase fuel economy. The eventual production of electricity and hydrogen in a renewable fashion, such as using solar energy, can achieve the long-term vision of having no tailpipe environmental impact, as well as eliminating the dependence of the transportation sector on dwindling supplies of petroleum for its energy. In this report we will demonstrate the solar-powered charging of the high-voltage nickel-metal hydride (NiMH) battery used in the GM 2-mode hybrid system. In previous studies we have used low-voltage solar modules to produce hydrogen via the electrolysis of water and to directly charge lithium-ion battery modules. Our strategy in the present work was to boost low-voltage PV voltage to over 300V using DC–DC converters in order to charge the high-voltage NiMH battery, and to regulate the battery charging using software to program the electronic control unit supplied with the battery pack. A protocol for high-voltage battery charging was developed, and the solar to battery charging efficiency was measured under a variety of conditions. We believe this is the first time such high-voltage batteries have been charged using solar energy in order to prove the concept of efficient, solar-powered charging for battery-electric vehicles.
Unique TiO2 nanotube arrays (TNAs) grafted with MnO2 nanosheets is synthesized for the first time as an anode for Li battery. The character of the special structure is MnO2 nanosheets grown on the outer, inner surface and tip of the TNAs. The composite combines the advantages both from MnO2 with high capacity (1230mAhg−1) and TNAs with excellent cycle stability and superior electrical conductivity. Besides, the MnO2 nanosheet layer with different thickness on the surface of TNAs is fabricated through controlling hydrothermal reaction time and it is found that the thickness has a significant impact on capacity, cycle performance and conductivity. Additionally, a very abnormal phenomenon that we call “late rise of capacity” is discovered in the capacity test after several hundreds of cycle times, for which a possible mechanism is proposed according to material characterization.
Episodic memory impairments caused by temporal lobe epilepsy (TLE) are well documented in the literature. Standard clinical episodic memory tests typically include a 30-min delayed recall test. However, in the past decade, it has become apparent that this standard test does not capture the full range of memory problems in TLE patients. Some patients perform well on a standard 30-min delayed recall test, but show Accelerated Long-term Forgetting (ALF) after 24 h. Although ALF has been investigated in patients with different types of epilepsy, current research on resected TLE patients is missing. In the present study, resected TLE patients were compared to a control group matched on initial learning. They showed normal performance on verbal recall after 30 min, but impairments became apparent after one week. Moreover, the significant interaction between participant group and memory test delay demonstrated that the patients indeed showed an acceleration in forgetting. Furthermore, ALF was present in both left and right resected TLE patients, which contradicts the presence of material-specific hemispheric differences in ALF. In addition, ALF was observed in seizure-free resected TLE patients, thereby demonstrating that this factor is not crucial for long-term memory deficits. The outcome shows that clinicians are likely to underestimate memory deficits in resected TLE patients and, therefore, advocates for the inclusion of ALF tests in standard clinical batteries for both pre- and post-surgery testing sessions.
If we consider Waste Electrical and Electronic Equipment (WEEE) management, we can see the development of different positions in developed and developing countries. This development started with the movement of WEEE from developed countries to the developing countries. However, when the consequences for health and the environment were observed, some developing countries introduced a ban on the import of this kind of waste under the umbrella of the Basel Convention, while some developed countries have been considering a regional or global WEEE recycling approach. This paper explores the current movements between Source and Destination countries, or the importers and exporters, and examines whether it is legal and why illegal traffic is still rife; how global initiatives could support a global WEEE management scheme; the recycling characteristics of the source an destination countries and also to ascertain whether the principle of Extended Producer Responsibility (EPR) has been established between the different stakeholders involved in WEEE management. Ultimately, the Full Extended Producer Responsibility is presented as a possible solution because the compensation of the environmental capacity for WEEE recycling or treatment could be made by the contribution of extra responsibility; and also generating an uniform standard for processing WEEE in an environmentally sound manner could support the regional or international solution of WEEE and also improve the performance of the informal sector.
The surface defects and grain boundary defects of organometallic halide perovskite films are detrimental to both the efficiency and stability of perovskite solar cells (PSCs). Furthermore, the electrical conductivity, work function and surface morphology of the hole transport layer (HTL) can also affect the performance of PSCs significantly. Here, we first have developed a novel synergistic strategy that uses multiple functional EMIC (1-Ethyl-3-methylimidazolium chloride) ionic liquid to modify PEDOT:PSS (poly (3, 4-ethylenedioxythiophene) polystyrene sulfonate) HTL, thereby obtaining the HTL with high electrical conductivity, low work function and smooth surface. Moreover, a novel S-acetylthiocholine chloride molecule which replaces expensive PCBM (phenyl-C61-butyric acid methyl ester) is developed to effectively passivate the negative- and positive-charged ionic defects in hybrid perovskite. The synergistic strategy extends the carrier recombination lifetime and reduces the charge trap density. In addition, the current hysteresis of the inverted device was also effectively eliminated. As a result, the champion cell in small area shows 20.06% efficiency with no hysteresis, along with an efficiency 18.77% for inverted PSCs in an active area of 1 cm2, both of which are the highest efficiency in the one-step PEDOT:PSS-based inverted PSCs so far. Compared to PCBM, the device passivated by S-acetylthiocholine chloride also has improved environmental stability (retaining 85% of initial PCE after 35 days storage without encapsulation in air with 60% humidity) and thermal stability (retaining 87% of initial PCE after 80 °C for 24 h storage without encapsulation under inert atmosphere).
The lithium–sulfur (Li–S) battery is a promising next-generation energy storage technology because of its high theoretical energy and low cost. Extensive research efforts have been made on new materials and advanced characterization techniques for mechanistic studies. However, it is uncertain how discoveries made on the material level apply to realistic batteries due to limited analysis and characterization of real high-energy cells, such as pouch cells. Evaluation of pouch cells (>1 A h) (instead of coin cells) that are scalable to practical cells provides a critical understanding of current limitations which enables the proposal of strategies and solutions for further performance improvement. Herein, we design and fabricate pouch cells over 300 W h kg−1, compare the cell parameters required for high-energy pouch cells, and investigate the reaction processes and their correlation to cell cycling behavior and failure mechanisms. Spatially resolved characterization techniques and fluid-flow simulation reveal the impacts of the liquid electrolyte diffusion within the pouch cells. We found that catastrophic failure of high-energy Li–S pouch cells results from uneven sulfur/polysulfide reactions and electrolyte depletion for the first tens of cycles, rather than sulfur dissolution as commonly reported in the literature. The uneven reaction stems from limited electrolyte diffusion through the porous channels into the central part of thick cathodes during cycling, which is amplified both across the sulfur electrodes and within the same electrode plane. A combination of strategies is suggested to increase sulfur utilization, improve nanoarchitectures for electrolyte diffusion and reduce consumption of the electrolytes and additives.
In this paper, the results of experimental work with doped natural graphite are presented and described. The graphite material plays major role within negative electrode materials used in lithium-ion batteries. Behavior of graphite used as an active material for negative electrodes in lithium-ion cell was widely investigated and published. The one key characteristic property of graphite is its irreversible capacity loss. The irreversible capacity represents losses which occur in the graphite negative electrode within initial charge-discharge cycles (process called cell formatting). This phenomenon is associated connected with lower negative electrode potential vs. lithium (Li/Li+) and the growth of the Solid Electrolyte Interphase (SEI) layer. The SEI layer is important and necessary for proper operation of the lithium-ion cell; on the other hand growth of the SEI layer limits and lowers the theoretical capacity of lithium-ion cell by up to 40%. A possible way how to offset these losses is to dope the graphite material by lithium atoms before its use in the lithium-ion cell. The lithiation process has been studied as a possible way how to dope the (pre-lithiated) natural graphite prior to its use as an active electrode material. Suppression of irreversible capacity losses at initial charge-discharge cycles is the main focus of our investigation.
Science is now studying biodiversity on a massive scale. These studies are occurring not just at the scale of larger plants and animals, but also at the scale of minute entities such as bacteria and viruses. This expansion has led to the development of a specific sub-field of “microbial diversity”. In this paper, I investigate how microbial diversity faces two of the classical issues encountered by the concept of “biodiversity”: the issues of defining the units of biodiversity and of choosing a mathematicalmeasure of diversity. I also show that the extension of the scope of biodiversity to microbial entities such as viruses and many other not-clearly-alive entities raises yet another foundational issue: that of defining a “lower-limit” of biodiversity.
The effect of ionomer content on the oxygen kinetics in fuel cells and metal-oxide batteries was investigated by varying ionomer loading with constant loadings of a silver nanowire catalyst. Silver nanowire inks were produced in which commercially available anionomer solution constituted 10, 25, 40, 50, and 75% of the total ink volume. Constant loadings of Ag nanowire catalyst were then deposited onto glassy carbon electrodes by varying the amount of ink deposited. These were then used in rotating disc electrode (RDE) experiments using a 0.1 M KOH electrolyte solution. From these experiments, using ORR polarization curves and Koutecky–Levich analysis, it was found that not only did the anionomer loading affect the total activity (given a constant Ag nanowire loading) but, that the anionomer content also had an impact upon the apparent kinetic limited current as well as whether the ORR proceeded through the 2e− or 4e− pathway. Although the total activity declined with very high anionomer loadings, the ORR appeared to proceed more through the 4e− pathway with increased anionomer content.
An alkaline polymer gel electrolyte (PGE) film was prepared by solution polymerization of acrylate–KOH–H2O at room temperature, and the preparation conditions were optimized in view of the mechanical properties and ionic conductivity of the film. The PGE film with the optimized composition of 0.02% K2S2O8, 16.75% acrylic acid and 83.23wt.% 4moll−1 KOH solution is transparent, rubber-like and dimensionally stable with improved mechanical properties as compared with gelled electrolyte. The specific conductivity of the film is 0.288scm−1 at room temperature and the conductivity values follow the Arrhenius equation with the activation energy of ∼10kJmol−1. These data suggest that the ionic conduction proceeds in the same mechanism as in aqueous alkaline solution. Experimental results from the laboratory Zn/Air, Zn/MnO2 and Ni/Cd cells using the PGE film as electrolyte demonstrate that the PGE film has almost the same chemical and electrochemical stability as aqueous alkaline solution, and shows good performance characteristics for application of alkaline primary and secondary battery systems.
With the rising penetration of intermittent renewable energy sources (RES) and their variable nature it has become a challenge for distribution grid operators to maintain voltage quality inside the permissible range. It requires the involvement of new distributed resources, such as energy storage devices, to smooth power fluctuations of RES and to avoid long-term voltage rises. To achieve the best results such devices should be located as close to the micro source as possible – behind the meter. Small, distributed energy storage devices could be used to increase self-consumption of generated energy inside microgrids, helping also to flatten the daily load curve of the electrical power system (EPS). This paper discusses the properties of selected energy storage technologies suitable for small-scale microgrids containing renewable energy sources. The properties of small Zinc Bromine (ZnBr) flow batteries obtained in experimental research have been presented and compared to the properties of other energy storage devices similarly classified but at a different level of development. The simple equivalent model of the ZnBr battery has also been developed and described.
To improve the safety of lithium-ion batteries, we studied non-flammable electrolytes made by adding several types of phosphazene-based flame retardants to conventional electrolytes and evaluated their conductivities, electrochemical characteristics, and the effects of flame retardants in terms of safety. Cell performance tests and abuse tests were also conducted using cylindrical test cells. The conductivity of electrolytes decreased when phosphazene-based flame retardants were added to the conventional electrolytes. The reason for this decrease in conductivity may be the increase in electrolyte viscosity caused by adding flame retardants. The conductivity decrease led to a decrease in cell capacity at high current density and at low temperature. However, the cell capacities at 0.2 CA (CA=750mA) and at 25°C were almost the same as those of cells using conventional electrolytes. Flame tests showed that the electrolytes with flame retardants exhibited flame resistance consistent with UL-94V0. We also carried out several abuse tests to check the safety improvements. Both overcharge tests up to 10V and heating tests up to 200°C were completed without any extraordinary heat generation. Heating tests using a burner revealed the self-extinguishing properties of these electrolytes which were gushed out by venting. These results indicate that electrolytes with phosphazene-based flame retardants are effective for making lithium-ion batteries safe.
Nanosized Ni3(Fe(CN)6)2(H2O) was prepared by a simple co-precipitation method. The electrochemical properties of the sample as the electrode material for supercapacitor were studied by cyclic voltammetry (CV), constant charge/discharge tests and electrochemical impedance spectroscopy (EIS). A specific capacitance of 574.7Fg−1 was obtained at the current density of 0.2Ag−1 in the potential range from 0.3V to 0.6V in 1M KNO3 electrolyte. Approximately 87.46% of specific discharge capacitance was remained at the current density of 1.4Ag−1 after 1000 cycles.
FeSi4P4 has been synthesized by a facile ball-milling method and evaluated as anode in sodium ion battery for the first time. The FeSi4P4 electrode can deliver a reversible capacity of 180mAhg−1 at 100mAg−1 with a capacity retention of 99% after 100 cycles. Experimental data and DFT calculation reveal that the sodium storage in FeSi4P4 is realized via the unusual insertion/extraction reaction. Our results demonstrate that transition metal phosphosilicides could be potential anode materials for sodium ion batteries.
A telemetry system for studying decapod crustacean behaviour is described which uses low frequency, digitally encoded electromagnetic tags whose signals are detected with a grid of loop aerials on the seabed. Electromagnetic telemetry can be used to study short range movements of cryptic animals in topographically complex habitats that are not amenable to ultrasonic telemetry. Digital encoding allows many individuals to be monitored simultaneously and one or more behavioural, physiological or environmental variables to be telemetered. In the present system, tag signals convey identity and a measure of activity derived from an integral tilt switch. Translocational movements are indicated by detection of tags with different aerials. A central data logger located on the seabed decodes and records tag signals and environmental measurements. Design life of tags is >1 year and the receiving system batteries are replaced by divers at intervals of up to 4 weeks. In field tests, crab (Cancer pagurus L.) and lobster (Homarus gammarus (L.)) activity was monitored at an artificial reef for 14 months. Examples of the type of information acquired are presented to illustrate the capabilities of the system and potential applications are discussed. Limitations of digital electromagnetic telemetry stem mainly from the short range of detection, the need for cables on the seabed and the size and shape of the transmitting tag.