batterydata/paper-abstracts huggingface dataset:
Lithium iron phosphate battery (LIPB) is a promising power source for electric vehicle. However, LIPBs generally show a low uniformity in performances due to their poor stability. Herein, we employ an electrochemical method to study the stability of LIPB, and the results show that stable LIPB can be obtained by using the activation with both charge–discharge cycle and aging, since the stable solid-electrolyte-interface (SEI) films are available. The stable SEI films are associated with the low self-discharge of LIPB, characterized by keeping high open circuit voltage (OCV) during storage under discharged states, high capacity, stable internal resistance, and high charge/discharge reversibility. Most of the low-OCV LIPBs can be repaired by using the electrochemical treatment containing charge–discharge cycle and aging. The activation processes with charge–discharge cycle and aging induce the generation of the smooth, adherent, and stable SEI films, contributing to the good stability of the battery. The achievement of the stable SEI films is mainly resulted from the formation of the surface layers completely covering the electrodes' surfaces during charge–discharge cycle, and the stabilization of the layers by transforming the layers' species to the “more inorganic” compounds such as carboxylates or even carbonates (like Li2CO3) during aging.
The large scale structure of poly(methyl methacrylate)-based gels and gel electrolytes has been investigated using small angle neutron scattering. The data reveal two different structural length scales: the shorter being typically 4–25 Å, while the larger is 200–300 Å. Comparison between the gel electrolytes, obtained by doping the gels with lithium salt, and the corresponding salt-free systems shows that the determined length scales are very similar. Thus the dissolved salt has only minor influence on the structure of the polymer network. We also discuss the important relations between structure, dynamics and the performance of the gel electrolytes.
A series of semi-fluorinated sulfonated polyimides (6F-SPIs) are designed and synthesized via a one-step high-temperature polycondensation reaction. The sulfonation degrees of 6F-SPIs are controlled through changing the ratio of sulfonated diamine to non-sulfonated diamine in the casting solution. The physico-chemical properties and single cell performance of 6F-SPI membranes are thoroughly evaluated and compared to a non-fluorinated SPI membrane (6H-SPI-50) and a Nafion 115 membrane. The results show that the designed 6F-SPI membrane with a 50% sulfonation degree (6F-SPI-50) possesses the highest proton selectivity (1.613×105 Smincm−3) among all tested membranes. Besides, the 6F-SPI-50 membrane exhibits a promising performance for vanadium redox flow batteries (VRFBs), showing higher coulombic efficiencies (96.90–99.20%) and energy efficiencies (88.25–64.80%) than the Nafion 115 membrane (with coulombic efficiencies of 90.60–96.70% and energy efficiencies of 81.04–60.10%) at the current densities ranging from 20 to 100mAcm−2. Moreover, the 6F-SPI-50 membrane shows excellent chemical stability in the VRFB system. This work paves the way for the development of a new class of 6F-SPI membranes for the VRFB application.
Chemically derived graphene holds great promise as an electrode material for electrochemical energy storage owing to its unique physical and chemical properties. Recent years have witnessed tremendous research breakthroughs in the field of graphene-based materials for electrochemical capacitors. This article presents a review of the latest developments in the functionalization of chemically derived graphene for improving its electrocapacitive properties. Beginning with a brief description of supercapacitors, graphene, and chemically derived graphene, we discuss the preparation, electrocapacitive properties, and drawbacks of chemically derived graphene and its derivatives, followed by a discussion on how to functionalize chemically derived graphene for improving its double-layer capacitance and pseudocapacitance. Emphasis is made on comparing and highlighting demonstrated approaches to functionalizing chemically derived graphene. Future research towards developing advanced electrochemical capacitors, perspectives and challenges are outlined.
The impact of flue gas from the combustion of natural gas or coal in a combustion test facility on the activity of catalysts for the synthesis of cyclic carbonates from epoxides and waste carbon dioxide has been investigated. In batch reactions with styrene oxide as substrate, some loss of catalyst activity was apparent and this was greater for catalyst exposed to flue gas generated from burning coal than for catalyst exposed to flue gas obtained by burning gas. In a gas-phase flow reactor with ethylene oxide as substrate, the detrimental effect of flue gas exposure on catalyst activity was much less apparent.
A carbon nanotubes (CNTs)-nickel-cobalt oxyhydroxide nanoflake core-shell structure is designed and fabricated by a facile one-step chemical bath deposition method at 80°C. After its annealing at 300°C, a CNTs/Ni-Co oxide core-shell heterostructure is thus achieved. Phase characterization proves that Ni-Co oxyhydroxide and Ni-Co oxide as shells are (Ni,Co)OOH and NiCo2O4, respectively. Structural analysis confirms that the as-synthesized oxyhydroxide and oxide shells are conformally coated on the external surface of CNTs. Electrochemical data demonstrate that (Ni,Co)OOH/CNTs composite exhibits a high specific capacitance of 853Fg−1 at 5mVs−1 and an excellent high rate capability, with 75% retention after a 10-fold increase in current density. Meanwhile, the hybrid of NiCo2O4/CNTs has an enhanced performance of 940Fg−1 at 5mVs−1. Its rate capability is much better than the oxyhydroxide precursor because of its high conductivity. Both of these heterostructures have an excellent cycling performance of 100% capacitance retention after 10,000 cycles and Coulombic efficiency. An asymmetric capacitor is also fabricated with (Ni,Co)OOH/CNTs as positive electrode and activated carbon as negative electrode. It possesses a high specific capacitance of 164Fg−1 and a high energy density of 73.8WhKg−1 within 1.8V.
Macroporous spinel-structured LiMn2O4 microparticles have been successfully prepared by a facile template-free synthesis process. Morphological characterization shows that the porous particles with size of about 4μm are composed of small primary particles of about 200nm with many tiny channels inside the microparticles. Electrochemical measurements reveal that the porous LiMn2O4 cathode has a high specific capacity and superior high rate performance. It exhibits a reversible discharge capacity of about 132.9mAhg−1 at a low charge/discharge rate of 0.1C. When tested at high rates of 20C and 50C, the discharge capacities still remain at 106 and 67mAhg−1, respectively. Furthermore, the porous LiMn2O4 possesses excellent cyclability. All the results suggest this porous LiMn2O4 to be highly promising for wide application in high power lithium ion batteries.
Lithium-sulfur (Li-S) batteries have been regarded as promising next generation rechargeable energy storage system, due to the high theoretical specific capacity and energy density. However, the low sulfur content in the cathode electrode greatly decrease the practical energy density of the Li-S batteries. Herein, we report a reduced graphene oxide-hollow carbon sphere (rGO-HCS) composite to encapsulate sulfur with high sulfur contents from 70 to 90wt% as sulfur cathode. The rGO-HCS/S composite loading 90wt% sulfur delivers the highest energy density of 1281Whkg⿿1 based on the mass of the whole cathode, even at a high sulfur areal density of 3mgcm⿿2, it could still reach a high discharge capacity of 860mAhg⿿1 (corresponding to 1300Whkg⿿1 based on mass of the whole cathode) and obtain a high capacity retention of 77% after 78 cycles.These results indicate the great potential of the rGO-HCS nanostructure as promising sulfur host loading high content of sulfur with high gravimetric and volumetric energy density.
Publisher Summary This chapter introduces a series of instructions that guides to take the next step depending on the results. This is called a methodology. Methodologies are made up of four types of “boxes” - Action Boxes, Discovery Boxes, Technique Boxes, and Example Boxes. Each box type has a different role in the methodology. Each box is exclusively labeled for reference and is grouped with similar boxes. Therefore, all the Action Boxes come first followed by the Discovery Boxes, then Technique Boxes, and finally Example Boxes. However, neither methodology can be read sequentially. This point bears repeating. The methodology is not a sequential document. In case anyone attempts to go through it in a sequential order, its consequences will be a complete chaos. There is no one path through the boxes. The essence of these methodologies is for a modeler or miner to take action, evaluate results, and take decisions on the basis of the results.
An industrial synthesis process for spherical lithium nickel cobalt mixed oxides, Li(Ni1−y Co y )O2, has been successfully applied to aluminum- and magnesium-doped lithium nickel cobalt mixed oxides Li(Ni1−y−z Co y M z )O2 (M=Al, Mg). The additional elements stabilize the layered structure and enhance the cycling stability. The decomposition temperature of charged electrodes depends on the delithiation state and the crystallite size but not directly on the content of dopants. Therefore, enhancement of the thermal stability by aluminum and magnesium seems mainly to be an indirect effect due to an intrinsic limitation of the delithiation.
Lithium-ion capacitors (LICs) emerge as the promising energy storage devices owing to their enhanced power density compared to batteries and superior energy density to electric double-layer capacitors. However, the wide use of graphite anodes in LICs results in intrinsic problems such as sluggish reaction kinetics and dendritic Li plating problem, while Li4Ti5O12-based electrodes exhibit low energy storage capacity and excessively high insertion potential. Herein, our research uncovers the synthesis of novel Li2TiSiO5 and carbon nanofibers (LTSO/C) via a morphology-preserved thermal transformation strategy as the high-performance anodes of LICs. LTSO/C electrodes with the unique 3D interconnected nanoarchitecture consisting of aggregation-free LTSO nanoparticles exbibit high-rate behavior (ca. 50% capacity retention from 0.1 to 10 A g−1), suitable Li+ insertion potential (0.1–1 V vs. Li/Li+), and high packing density of 1.93 g cm−3 (highly comparable to graphite and larger than Li4Ti5O12). Moreover, analysis on reaction kinetics has revealed that such high-rate performance can be attributed to the pseudocapacitive charge storage mechanism of as-synthesized LTSO/C electrodes. Afterwards, novel LICs employing LTSO/C anodes to replace graphite and Li4Ti5O12 further yield high working potential of 4.2 V and large gravimetric energy and power densities. These results thus suggest a great promise of the proposed materials selection and nanostructure design for ultrafast and stable energy storage devices.
Costa Rica, a small country with the population of 4 million, and without military and hence no military expenditure, promotes the use of renewable sources like Hydro, Mini hydro, Wind, Geothermal and Sun, mainly for electricity generation. Almost 90% of the electricity is produced from these renewable sources. Through different policies and some incentives, etc., private generation is also encouraged and there are some decentralized systems like solar water heaters, swimming pool heaters, cookers, dryers and stills and also photo voltaic panels. The last ones are mostly for the population where there is no electric grid. Depending on the province, 91–99.5% of the population is electrified. Government also encourages the use of energy saving devices specially at domestic and industrial sector. In addition to provide these data, some of the solar energy systems are mentioned.
The conventional module has many deficiencies during its long-term operation on environmental conditions. Examples of such deficiencies are cracked cells, interconnection failure and degradation of the electrical output power. Also, the module is not repairable, once one cell is degraded the module needs to be replaced. In this work the fabrication and testing of the 3FPT module is presented. The 3FPT module is a newly developed photovoltaic module structure, which overcomes the drawbacks of the conventially existing modules and uses commercially available materials in Egypt. The 3FPT module consists of three plates; the front cover, cells adhered to substrate and the back cover. A 0.065 m2 photovoltaic module is fabricated using four single crystal cells each of 0.102 m diameter. The tests carried out on the 3FPT module after fabrication are X-ray radiography examination, illumination measurements, dark measurements, electrical isolation test, electrical performance test, non-destructive tests, environmental test, thermal cyclic test, humidity test, thermal shock test and cyclic pressure loading test. An experimental setup was arranged to gather actual temperature measurement data for the different 3FPT module encapsulation layers of interest. The temperature measurement data were recorded every half hour from 10 a.m. to 3 p.m. during November and December of 1997 in the Cairo area. Also, an experimental setup is arranged to measure the transmissivity and reflectivity behavior for different front cover materials. The results of those tests and measurements leads to the optimum design criteria of the 3FPT module with simple fabrication technique and good performance.
Objectives To demonstrate the ability of the Screen for Cognitive Impairment in Psychiatry (SCIP-S) to discriminate between cognitively-impaired individuals and those with adequate functioning in a sample of schizophrenic and bipolar patients, as well as in a control group. Methods The SCIP-S, together with a full neuropsychological battery, was administered to three groups: patients with schizophrenia, patients diagnosed with bipolar disorder I, and controls. The battery scores were used to perform a standardization with respect to the control group and this served to determine the comparison groups (cognitively impaired versus unimpaired) for each of the subtests of the SCIP-S. A full analysis of decision validity was conducted on the basis of receiver operating characteristic curves (sensitivity and specificity, +LR and −LR, PPV and NPV). Results All the subtests yielded adequate values for sensitivity and specificity with the proposed cut-off points, while the total score of the SCIP (<70) was associated with a sensitivity of 87.9 and specificity of 80.6. Conclusions The SCIP-S shows adequate decision validity as a screening tool for cognitive deficit in patients diagnosed with schizophrenia or bipolar disorder.
Electrochemical conversion of metal hexacyanoferrates into their oxides or hydroxides was successfully achieved and reported using nickel hexacyanoferrates (Ni-HCF). Herein, a versatile strategy for such a conversion was explored by potential cycling Ni(OH)2 nanoparticle film modified electrodes in K3[Fe(CN)6] or K4[Fe(CN)6] solution. The results show that K3[Fe(CN)6] is more prone to the conversion from Ni(OH)2 to Ni-HCF. Their composition, morphology, and structure were characterized by the techniques such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and UV–vis spectrometry. The reaction mechanism is tentatively given. This strategy is also suitable for the other metal hydroxides including rare earth hydroxides such as neodymium, samarium etc.
Recent advances in genetic toxicity (mutagenicity) testing methods and in approaches to performing risk assessment are prompting a renewed effort to harmonize genotoxicity risk assessment across the world. The US Environmental Protection Agency (EPA) first published Guidelines for Mutagenicity Risk Assessment in 1986 that focused mainly on transmissible germ cell genetic risk. Somatic cell genetic risk has also been a risk consideration, usually in support of carcinogenicity assessments. EPA and other international regulatory bodies have published mutagenicity testing requirements for agents (pesticides, pharmaceuticals, etc.) to generate data for use in genotoxicity risk assessments. The scheme that follows provides a proposed harmonization approach in which genotoxicity assessments are fully developed within the risk assessment paradigm used by EPA, and sets out a process that integrates newer thinking in testing battery design with the risk assessment process. A classification strategy for agents based on inherent genotoxicity, dose-responses observed in the data, and an exposure analysis is proposed. The classification leads to an initial level of concern for genotoxic risk to humans. A total risk characterization is performed using all relevant toxicity data and a comprehensive exposure evaluation in association with the genotoxicity data. The result of this characterization is ultimately used to generate a final level of concern for genotoxic risk to humans. The final level of concern and characterized genotoxicity risk assessment are communicated to decision makers for possible regulatory action(s) and to the public.
Choosing the optimal type and size of energy storage for a given hybrid maritime vessels is challenging. Investment cost, fuel saving and energy storage expected life time will be affected by the choices. Furthermore, the optimum choices depend on the operation profile of the vessel as well as safety related constraints in different vessel mode of operations. In addition, the optimum power management strategy will be mode dependent as well as dependent on the type and size of onboard energy storage. Finally, the total system has to fulfill certain safety related rules and regulations that typically both favour the use of storage and set some constraints to the size and the utilization of the storage. In this paper we propose a mathematical optimisation model called OBLIVION that stands for “Optimised Battery Lifetime In Vessels Internal Operations and Networks”. OBLIVION is created to support battery investment decisions. Beyond including battery degradation and desired battery lifetime in the choice, the model facilitates analysis of how the investment decisions change for different combinations of vessel operation modes. The key contribution of this paper is the proposed methodology to formulate technical and safety constraints, represent different vessel modes of operation and battery storage degradation in a way suitable for inclusion within mathematical optimisation models. Moreover, analyses that demonstrate how these features affect the storage investment decisions are presented. Mathematical formulations of constraints such as closed and open bus-tie breaker operation, true spinning reserve requirements as well as spinning reserve provided by batteries are included as well.
Increasing demands of rare earth (RE) metals for advanced technological applications coupled with the scarcity of primary resources have led to the development of processes to treat secondary resources like scraps or end of life products that are often rich in such metals. Spent NdFeB magnet may serve as a potential source of rare earths containing around ∼30% of neodymium and other rare earths. In the present investigation, a pyro-hydrometallurgical process has been developed to recover rare earth elements (Nd, Pr and Dy) from the spent wind turbine magnet. The spent magnet is demagnetized and roasted at 1123 K to convert rare earths and iron to their respective oxides. Roasting of the magnet not only provides selectivity, but enhances the leaching efficiency also. The leaching of the roasted sample with 0.5 M hydrochloric acid at 368 K, 100 g/L pulp density and 500 rpm for 300 min selectively recovers the rare earth elements almost quantitatively leaving iron oxide in the residue. Leaching of rare earth elements with hydrochloric acid follows the mixed controlled kinetic model with activation energy (Ea) of 30.1 kJ/mol in the temperature range 348–368 K. The leaching mechanism is further established by characterizing the leach residues obtained at different time intervals by scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray diffraction (XRD). Individual rare earth elements from the leach solution containing 16.8 g/L of Nd, 3.8 g/L Pr, 0.28 g/L of Dy and other minor impurity elements could be separated by solvent extraction. However, mixed rare earth oxide of 99% purity was produced by oxalate precipitation followed by roasting. The leach residue comprising of pure hematite has a potential to be used as pigment or can find other applications.
Effective planning for protected areas and wildlife population management requires a firm understanding of the location of the species’ core habitat patches, the dispersal corridors connecting them, and the risk they face from key threats, notably deforestation.
Sodium–nickel chloride (ZEBRA) batteries are typically operated at relatively high temperatures (3 300 °C) to achieve adequate electrochemical performance. In the present study, the effects of operating temperature on the electrochemical performance of planar-type Na/NiCl2 batteries were investigated to evaluate the feasibility of battery operation at low temperatures (£200 °C). The planar-type cell was able to be cycled at C/3 rate at as low as 175 °C despite higher cell polarization. Overall, low operating temperature resulted in a considerable improvement in the stability of cell performance. Cell degradation was negligible at 175 °C, while 55% increase in end-of-charge polarization was observed at 280 °C after 60 cycles. SEM analysis indicated that the degradation at higher temperatures was related to the particle growth of both nickel and sodium chloride. The cells tested at lower temperatures (£200 °C), however, exhibited a sharp drop in voltage at the end of discharge due to the diffusion limitation, possibly caused by the limited ionic conductivity of catholyte or the poor wettability of sodium on the β″-Al2O3 solid electrolyte (BASE). Therefore, improvements in the ionic conductivity of catholyte and sodium wetting as well as reduction in the ohmic resistance of BASE are required to enhance the battery performance at low temperatures.
The LiTi2(PO4)3 has been successfully synthesized by a PEG (polyethylene glycol, mean molecular weight of 2000) based sol–gel route at a relative low temperature. For further improve its electrochemical properties, a ball milling process with acetylene black has been used to form LiTi2(PO4)3/C nanocomposite. The samples are characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Electrochemical performance of the samples is characterized by the charge–discharge test and cyclic voltammetry. The results show that the ball milling process enables LiTi2(PO4)3 nanoparticles networked with conductive acetylene black, which offered higher electrochemical performance. The LiTi2(PO4)3/C nanocomposite delivers a higher specific capacity, enhanced rate capability, and better cyclability.
An epitaxial-film model electrode of LiCoO2(104) was fabricated on SrRuO3(100)/Nb:SrTiO3(100) using pulsed laser deposition. The 50 nm thick LiCoO2(104) film exhibited lithium (de-)intercalation activity with a first discharge capacity of 119 mAh g−1 between 3.0 and 4.4 V, followed by a gradual capacity fading with subsequent charge-discharge cycles. In contrast, a 3.2 nm thick Li3PO4-coated film exhibited a higher intercalation capacity of 148 mAh g−1 with superior cycle retention than the uncoated film. In situ surface X-ray diffraction measurements revealed a small lattice change at the coated surface during the (de-)intercalation processes compared to the uncoated surface. The surface modification of LiCoO2 by the Li3PO4 coating could lead to improvement of the structural stability at the surface region during lithium (de-)intercalation at high voltage.