batterydata/paper-abstracts huggingface dataset:
Non-metallic elements such as carbon, oxygen, and nitrogen in liquid sodium exert a significant effect on the material behaviour of cell construction materials in liquid metal battery systems. Austenitic Fe-18%Cr-8%Ni foil and α-iron foil are equilibrated at 550 °C in sodium, and, subsequently, the concentration of carbon in the foils is analysed. A new relationship has been obtained between carbon activity and carbon concentration in α-iron foil, and is compared with the previously developed ones involving 304 SS foil reference samples. An equilibrium method has been developed to measure the activity of carbon in liquid sodium by using α-iron with this new expression. The results show similar values to those obtained with the 304 SS foil reference samples.
The methanolic crude and methanol–aqueous extract of Alstonia macrophylla leaves and n-butanol part of the crude extract showed antimicrobial activity against various strains of Staphylococcus aureus, Staphylococcus saprophyticus, Streptococcus faecalis, Escherichia coli, Proteus mirabilis, Trichophyton rubrum, Trichophyton mentagrophytes var. mentagrophytes and Microsporum gypseum. The minimum inhibitory concentration (MIC) values ranges from 64 to 1000 μg/ml for bacteria and 32–128 mg/ml for dermatophytes. However, the strains of Pseudomonas aeruginosa, Klebsiella sp. and Vibrio cholerae showed resistance against in vitro treatment of the extracts up to 2000 μg/ml concentration, while the two yeast species were resistant even at 128 mg/ml concentration. The stem bark extract prepared similarly was found to be less active compared to the leaves. Phytochemical study indicates that the crude extract contains tannins, flavonoids, saponins, sterols, triterpene and reducing sugars. Further fractionation and purification of n-butanol part of the extract showed the presence of β-sitosterol, ursolic acid, β-sitosterol glucoside and a mixture of minor compounds only detected in TLC.
The three dimensional hierarchical carbon microflowers decorated with MoO2 nanoparticles (MoO2/CF) were fabricated by a facile method. During the experiment process, MoO4 2− anions are attached on the dopamine along with self-polymerization of dopamine under alkaline solution, forming the Mo-polydopamine compound (AHM-PDA). Then it is carbonized, forming MoO2/CF. The size of the MoO2/CF can be adjusted by the amount of dopamine, and the MoO2 nanoparticles decorated on the carbon microflowers are 1–2 or 30–50nm in size at different conditions. Owing to the unique structure, the obtained MoO2/CF composite exhibits a high reversible specific capacity of 690mAhg−1 after 200 cycles at 500mAg−1, and even displays 576mAhg−1 at 1000mAg−1 after 200 cycles. The improved electrochemical performance suggests that MoO2/CF composite is a promising anode material for lithium ion storage.
Automotive Li-ion cells are becoming much larger and thicker in order to reduce the cell count and increase battery reliability, posing a new challenge to battery heating from the cold ambient due to poor through-plane heat transfer across a cell's multiple layers of electrodes and separators. In this work, widely used heating methods, including internal heating using the cell's resistance and external heating by resistive heaters, are compared with the recently developed self-heating Li-ion battery (SHLB) with special attention to the heating speed and maximum local temperature critical to battery safety. Both conventional methods are found to be slow due to low heating power required to maintain battery safety. The heating power in the external heating method is limited by the risk of local over-heating, in particular for thick cells. As a result, the external heating method is restricted to ∼20 min slow heating for a 30 °C temperature rise. In contrast, the SHLB is demonstrated to reach a heating speed of 1–2 °C/sec, ∼40 times faster for large-size thick cells, with nearly 100% heating efficiency and spatially uniform heating free from safety concerns.
Magnesium-sulfur (Mg-S) batteries are highly attractive because of their high theoretical energy density, low cost and safety features. However, severe capacity fading issues limit their development, which are greatly associated with reaction processes at electrode/electrolyte interfaces. Herein, we systematically studied the interfacial processes of Mg deposition/stripping in ether-based electrolytes at nanoscale by in situ atomic force microscopy (AFM). It can be directly observed the initial nucleation of bowl-like structure and deposition of crystallized Mg upon charge in tetraglyme (TEG) - based electrolyte, followed with uniform stripping process upon discharge. In contrast, the initial nucleation of bowl-like structure, fast stack of nanoparticles (NPs) and deposition of crystallized Mg upon charge can be observed in diglyme (DEG) - based electrolyte, followed with nonuniform stripping process upon discharge. Combined with in situ optical imaging, former system shows better reversibility upon cycle. The present results reveal a direct insight into the structure-reactivity correlation at anode/electrolyte interfaces, which provides deep understanding of the interfacial mechanism to guide the design and development of the high-energy Mg-S batteries.
A novel La0.7Sr0.3MnO3-CeO2 (LSM-CeO2) hybrid catalyst for oxygen reduction reaction (ORR) has been synthesized by a facile one-pot method. The flower-like CeO2 with the diameter of about 3 μm is formed by the agglomeration of nanosheets with the thickness of about 40 nm. The LSM particles with the diameter of about 150 nm are well distributed on the flower-like CeO2, thus the interaction between LSM and CeO2 is built. Therefore, the LSM-CeO2 composite catalyst exhibits the much higher catalytic activity toward ORR with the direct four-electron transfer mechanism in alkaline solution than LSM or CeO2. Furthermore, the stability of LSM-CeO2 is superior to that of Pt/C, and the current retention is 93% after 100000 s. The maximum power density of the aluminum-air battery using LSM-CeO2 as the ORRC can reach 238 mW cm-2, which is about 29% higher than that with LSM (184 mW cm-2). It indicates that LSM-CeO2 composite material is a promising cathodic electrocatalyst for metal-air batteries.
In this paper, two empirical studies are presented in which an attempt was made to explain individual differences in two different aspects of 4-year-olds’ suggestibility, that is, their ability to resist false suggestions and memory impairments due to prior misinformation. As sources of individual differences cognitive skills along the information processing pathways were chosen: executive functioning (Study 1) and working memory (Study 2). Additionally, memory for the observed event and language proficiency were included in the studies. The results revealed that overall individual differences in language skills made a significant and consistent contribution to individual differences in the included measures of children's susceptibility to suggestions. Executive function and working memory skills were not directly related to children's tendency to yield false suggestions and their memory impairments in a recognition test after being misled. However, both executive function and working memory were related to children's language proficiency pointing to a possible indirect effect and underlining the importance of language competencies in early childhood.
The effect of an epoxy resin coating on the electrochemical performance of Li-ion batteries is investigated. Mesocarbon microbeads (MCMB), which constitute a promising carbon anode material for rechargeable Li-ion batteries is used as a starting carbon material. The surface coating of the MCMB is carried out by refluxing in a dilute H2SO4 solution and mixing in the epoxy resin-dissolved tetrahydrofuran (THF) solution. After heat treatment at 1000–1300°C, the resin coating layer on the MCMB is converted to an amorphous phase which is identified by means of a high resolution transmission electron microscope (HRTEM) and a electron energy loss spectroscopy (EELS) analyses. The Brunauer–Emmett–Teller (BET) surface area of MCMB is increased by the formation of the amorphous epoxy resin coating layer. The electrochemical performance of the MCMB, such as the charge–discharge capacity and cycleability, is enhanced by the surface modification through epoxy resin coating. The reasons for the improvement of electrochemical performance are discussed in terms of the results from HRTEM observation, EELS analysis, and cyclicvoltammetry
The objectives of REACH cannot be achieved under the current risk assessment approach. A change in mind set among all the relevant stakeholders is needed: risk assessment should move away from a labor-intensive and animal-consuming approach to intelligent and pragmatic testing, by combining exposure and hazard data effectively and trying to group chemicals (category approaches). The focus should be on reducing the overall uncertainties of 30,000 chemicals while acknowledging the existence of the uncertainty paradox: reducing uncertainty in the assessment of individual chemicals following the classical chemical-by-chemical approach as we have in previous decades will result in a prolongation of uncertainty for the entire group of 30,000 chemicals as a whole. With the first REACH registration deadline (2010) rapidly approaching, a mind set change is urgently needed. We can speed up the regulatory acceptance process, starting with the maximum use of currently available exposure and hazard data, tools and models. Optimal use should also be made of experimental exposure and hazard data generated under REACH. Only such an approach will make it possible to obtain a sufficient level of information within the time frame of REACH. A much more intensive dialogue between stakeholders is necessary.
Three-dimensional (3D) flower-like NiCo2O4 (F-NiCo2O4) is synthesized through using graphene oxide (GO) as “designer additives” to induce Ni-Co 1,3,5-benzenetricarboxylate metal-organic framework (Ni-Co-BTC MOF) from nanoparticles to form nanoneedles, and then further self-assembles to a 3D flower-like morphology. A possible process of morphological change is described in detail according to the changing amount of GO and reaction time. The as-prepared unique structure constructed by ultrafine subunits exhibits a high specific surface area (152.8 m2 g−1) and plentiful mesopores. As an anode in lithium-ion battery, F-NiCo2O4 shows a high capacity of 1167 mA h g-1 at a current density of 200 mA g−1 and even maintains 333 mA h g-1 at a high rate of 5000 mA g−1. Moreover, the 3D flower-like F-NiCo2O4 remains a high capacity of 1067 mA h g-1 at 1000 mA g−1 after 400 cycles. The novel method in this work paves a new way to form 3D structure by using GO to induce MOF aggregation, which may be extended to preparing other metal/metal oxides materials for electrochemical energy-storage systems.
This work reports on hollow carbon nanofibers (HCNFs) as anode materials for Li-ion batteries. Various HCNFs are synthesized using co-axial electrospinning of styrene-co-acrylonitrile (core) and poly(acrylonitrile) (shell) solutions and subsequent thermal treatments. The microstructures of HCNFs are examined using SEM, Raman spectroscopy, WAXD, and HR-TEM. The effect of the carbonization temperature on their turbostratic carbon structures and electrochemical properties is systematically investigated. As the carbonization temperature increases, both crystallite thickness and length significantly increases while the initial irreversible capacity decreases. These predictable microstructure and electrochemical performance of HCNFs provide important insight for the design of novel nanostructured anode materials such as Si or Sn encapsulated HCNFs.
The Raman mapping technique is shown to be suitable for quality control of both positive and negative electrodes for lithium-ion batteries. An analysis of the spectral features observed at a multitude of locations on the electrode surface allows a distribution of band parameters to be obtained that is unique for a given kind of electrode. It is shown that band positions, linewidths, and intensity ratios can be employed as descriptors of the distribution. Such distributions can in turn be used to generate a fingerprint for a particular kind of electrode.
Despite the high theoretical capacity of Si anodes, their huge volume change and poor electrical connectivity must be overcome by decreasing the feature sizes of the Si particles to the nanoscale and compositing them with highly conductive carbon materials. To ensure the mechanical integrity of the electrodes with uniform dispersion and good electrical contact of the nano-silicon, the industry has to use a relatively low amount of Si (<15% by mass) in commercial anodes. Such a low Si content severely weakens the capacity advantage of silicon at the electrode level. Here, we designed a cellulose-based topological microscroll by the self-rolling of cellulose nanosheets to form a binder-free, flexible, and free-standing electrode comprising an unprecedented 92% silicon content. In the microscroll, carbon-coated silicon nanoparticles are anchored on conductive carbon nanotubes and subsequently confined in cellulose carbon rolls with enough internal voids to accommodate the volume expansion of silicon; thus, a uniform dispersion of silicon with high reactivity was achieved. This structure shows an ultrahigh electrode-specific capacity of 2700 mA h g−1, excellent cycling stability under a high silicon content of 85% (>2000 mA h g−1 after 300 cycles) and a commercial-level areal capacity (5.58 mA h cm−2). This strategy offers a new way to design electrodes with a high active material content for high performance batteries.
Porous carbon nanofibers (CNFs) enriched with the graphitic structure were synthesized by thermal decomposition from a mixture containing polyethylene glycol and nickel chloride (catalyst). The textural and electrochemical properties of porous CNFs were systematically compared with those of commercially available multi-walled carbon nanotubes (MWCNTs). The high ratio of mesopores and large amount of open edges of porous CNFs with a higher specific surface area, very different from that of MWCNTs, are favorable for the penetration of electrolytes meanwhile the graphene layers of porous CNFs serve as a good electronic conductive medium of electrons. The electrochemical properties of porous CNFs and MWCNTs were characterized for the application of supercapacitors using cyclic voltammetry, galvanostatic charge–discharge method, and electrochemical impedance spectroscopic analyses. The porous CNFs show better capacitive performances (C S =98.4Fg−1 at 25mVs−1 and an onset frequency of behaving as a capacitor at 1.31kHz) than that of MWCNTs (C S =17.8Fg−1 and an onset frequency at 1.01kHz). This work demonstrates the promising capacitive properties of porous CNFs for the application of electrochemical supercapacitors.
This paper presents optimal sizing algorithms of grid-connected photovoltaic-battery system for residential houses. The objective is to minimize the total annual cost of electricity. The proposed methodology is based on a genetic algorithm involving a time series simulation of the entire system and is validated using data collected through one year. Genetic algorithm jointly optimises the sizes of the photovoltaic and the battery systems by adjusting the battery charge and discharge cycles according to the availability of solar resource and a time-of-use tariff structure for electricity. Houses without pre-existing solar systems are considered. The results show that jointly optimizing the sizing of battery and photovoltaic systems can significantly reduce electricity imports and the cost of electricity for the household. However, the optimal capacity of such photovoltaic battery varies strongly with the electricity consumption profile of the household, and is also affected by electricity and battery prices. Besides individual PV generation and battery storage for each house, this paper also investigates group battery optimizations for communities with different consumption levels or with different energy demand diversity to see their effects on optimal sizing and peak demands for aggregated PV-battery system.
Ba0.5Sr0.5CoxFe1-xO3-δ phases, with 0.75 < x < 0.90, so-called BSCFs, were investigated as pseudocapacitive electrode materials. These polycationic oxide phases were prepared by a modified glycine-nitrate process and show the same perovskite structural arrangement and similar morphological characteristics in the whole series. The electrochemical performance was evaluated in aqueous electrolytes at room temperature. BSCF powders showed promising pseudocapacitive behavior as electrode materials with high volumetric capacitances which depend on the Co/Fe ratio. A volumetric capacitance of 500 F cm−3, i.e. five times higher than that of a standard activated carbon electrode, was measured in 5.0 M LiNO3 for the electrode based on Ba0.5Sr0.5Co0.8Fe0.2O3-δ material composition (x = 0.80). The electrode also exhibited moderate self-discharge and 90% of capacitance retention over 2000 cycles. The charge storage mechanism seems to be dependent upon the nature of the ions in the electrolyte and on the Co/Fe ratio.
This paper deals with the control and management of a hybrid power system composed of two clean generators connected to the load via a DC-Bus. The system configuration can solve certain problems inherent to reliability and power supply quality emanating from generators renewable energy resources based connected to the load. Since the primary natural energy resource cannot be easy to handle due to fluctuations appearing at the output. This can be solved by using an adequate control strategy including intermediate energy storage. The paper describes some research works achieved till now in hybrid energy system area, including the assessment of the modeling and control methods used and a survey of control problems which must be carried out. The main contribution in this paper focuses with modeling the hybrid PV/PEMFC energy system, using Matlab/Simulink, optimizing a hybrid system devices using artificial intelligence and carrying out simulation studies using a real climate data and practical load profile. A comprehensive results of simulation showed that the model is effective, operational and that backup system composed of PEM Fuel Cells and electrolyser can be integrated with photovoltaic power systems to provide uninterrupted high-quality power.
Fuel cells are a promising technology solution for reliable and clean energy because they offer high energy conversion efficiency and low emission of pollutants. However, high cost and insufficient durability are considerable challenges for widespread adoption of polymer electrolyte membrane fuel cells (PEMFCs) in practical applications. Current PEMFCs catalysts have been identified as major contributors to both the high cost and limited durability. Atomic layer deposition (ALD) is emerging as a powerful technique for solving these problems due to its exclusive advantages over other methods. In this review, we summarize recent developments of ALD in PEMFCs with a focus on design of materials for improved catalyst activity and durability. New research directions and future trends have also been discussed.
Currently, the suitable proportion of inorganic particles in the ceramic separator has not been reported yet, due to the contradictory about the content of nano-particles in research papers (10 wt.%) and commercial application (large amount) [1,2]. In this paper, the nano-CeO2 contents on the properties of polyethylene (PE)-supported separator coating with poly (methyl methacrylate-butyl acrylate-acrylonitrile-styrene) (P(MMA-BA-AN-St)) copolymer is investigated systematically used in high voltage batteries for the first time. Since the copolymer contributes to high electrolyte uptake, and nano-CeO2 dedicates dimensional stability, the separator with 10 wt.% nano-CeO2 shows the highest ionic conductivity (2.5 × 10−3 S cm−1) at room temperature and the maximal electrolyte uptake (81.0 g m−2), while the separator with 100 wt.% nano-CeO2 exhibits better mechanical strength (52 MPa) and smaller shrinkage percentage (36%). Successively, cyclic performance of Li/LiNi0.5Mn1.5O4 cells indicates that the capacity retention of the cell using separator with 100 wt.% nano-CeO2 (72%) is second only to that with 10 wt.% nano-CeO2 (74%) after 200 cycles at 0.2 C between 3 V and 5 V, far larger than that without doping nano-CeO2 (51%) and PE (40%). By the consideration both of comprehensive performances and economic cost, 100 wt.% content is regarded as the most suitable appending proportion.
Predicting the remaining range of a battery reliably, accurately and simply is imperative for effective power management of electrified vehicles and reducing driver anxiety resulting from perceived low driving range. Techniques for predicting the remaining range of an electric vehicle exist; in the best cases they are scaled by factors that account for expected energy losses due to driving style, environmental conditions and the use of on-board energy consuming devices such as air-conditioning. In this work, experimental results that establish the dependence of remaining electrical energy on the vehicle battery immediate cycling history are presented. A method to estimate the remaining energy given short-term cycling history is presented. This method differs from the traditional state of charge methods typically used in battery management systems by considering energy throughput more directly.
Lithium based battery technologies are increasingly being considered for large-scale energy storage applications such as grid storage associated with wind and solar power installations. Safety and cost are very significant factors in these large scale devices. Ionic liquid (IL) electrolytes that are inherently non-volatile and non-flammable offer a safer alternative to mainstream lithium battery electrolytes, which are typically based on volatile and flammable organic carbonates. Hence, in recent years there have been many investigations of ionic liquid electrolytes in lithium batteries with some highly promising results to date, however in most cases cost of the anion remains a significant impediment to widespread application. Amongst the various possible combinations the dicyanamide (DCA) anion based ionic liquids offer exceptionally low viscosities and high conductivities – highly desirable characteristics for Li electrolyte solvents. DCA ILs can be manufactured relatively inexpensively because DCA is already a commodity anion, containing only carbon and nitrogen, which is produced in large amounts for the pharmaceutical industry. In this study we use the non-fluorinated ionic liquid N-methyl-N-butylpyrrolidinium dicyanamide to form non-volatile lithium battery electrolytes. We demonstrate good capacity retention for lithium metal and LiFePO4 in such electrolytes and discharge capacities above 130 mAh.g−1 at 50 °C. We show that it is important to control moisture contents in this electrolyte system in order to reduce capacity fade and rationalise this observation using cyclic voltammetry and lithium symmetrical cell cycling. Having approximately 200 ppm of moisture content produces the optimum cycling ability. We also describe plastic crystal solid state electrolytes based on the DCA anion in the lithium metal–LiFePO4 battery configuration and demonstrate over 150 mAh.g−1 discharge capacity without any significant capacity fading at 80 °C.