batterydata/paper-abstracts huggingface dataset:
The practical applications of lithium-sulfur (LiS) batteries remains remote because of low utilization of sulfur and short cycle life caused by low conductivity of sulfur, shuttle effect of lithium polysulfides and severe volume expansion. It is therefore exigent to rationally design an effective sulfur host. Here a novel sulfur host material--alpha molybdenum trioxide (α-MoO3) spheres are introduced into LiS battery cathode acting as lithium polysulfides absorbent and efficient matric of sulfur. The abundant oxygen atoms on the surface of α-MoO3, making it form chemical binding interactions with lithium polysulfides, which can effectively alleviate the dissolution of lithium polysulfides. Moreover, α-MoO3 as the matric of sulfur alleviates volume expansion of active sulfur and enhanced the utilization of sulfur, which results in improving the battery performances. As a result, S/α-MoO3 electrode with the sulfur content of 68 wt.% shows an initial discharge capacity of 1086.2 mAh g−1 and good capacity retention is obtained with 912.8 mAh g−1 after 400 cycles at 0.5 C. After 50 cycles at rates ranging from 0.1 to 2 C, the cell still returns a high specific capacity of 916.5 mAh g−1 at 0.5 C. The results demonstrate α-MoO3 was a promising sulfur host material for promoting the performances of LiS batteries with high sulfur content cathode.
Vanadium acetylacetonate, or V(acac)3, provides a model chemistry for investigating the performance of nonaqueous disproportionation flow batteries. A flow reactor was developed to implement studies of efficiency, energy capacity, and power capability with respect to electrolyte flow rate and current density. Reactors incorporating a porous separator allowed V(acac)3 to be cycled without appreciable capacity fade at current densities up to 100 mAcm−2. Experiments at the lowest flow rate, 12.5 mLmin–1, revealed limitations imposed by residence time within the reactor, which manifested as high charging overpotentials. These overpotentials vanish above 25 mLmin–1. A higher flow rate of 50 mLmin–1 yielded performance similar to cells at 25 mLmin–1, but could improve performance at current densities above 100 mAcm−2. Extrapolation of power density's dependence on current suggests a maximum power of 0.22 Wcm−2 for cells run at 206 mAcm−2. Energy efficiency passes through a maximum of 71% at 40 mAcm−2 and the corresponding energy density suggests that the chemistry can, in principle, deliver above 13 WhL−1 in acetonitrile solutions and above 24 WhL−1 in mixed-solvent solutions with higher V(acac)3 solubility. A V(acac)3 cell run at 40 mAcm−2 is shown to exhibit stable capacity and performance for more than 150 cycles.
The Istanbul composting and recycling plant, constructed in 2001, is one of the few composting plants in Turkey. During test operations of the plant, it was reported that the weight of the oversize materials (OM) above a 80-mm sieve was about 40% of the total incoming waste. They mainly consist of plastic bags that were full of garbage, which resulted in operational problems in the plant. In this paper, the composition of OM was determined and evaluated, particularly to find the economic losses in the plant. It was determined that approximately 58% of the OM transferred to the landfill area due to operational failures and interruptions could be used at the plant with improved operational conditions. Otherwise, the plant would realize an annual economic loss of about 640,800US$. Compost quality in the plant has been satisfactory, but source separated collection, at least the separation of the wet from the dry fraction, is needed to increase the amount of compost and recovered materials.
African American women are at increased risk for poor pregnancy outcomes compared to other racial-ethnic groups. Single or multiple psychosocial and behavioral factors may contribute to this risk. Most interventions focus on singular risks. This paper describes the design, implementation, challenges faced, and acceptability of a behavioral counseling intervention for low income, pregnant African American women which integrated multiple targeted risks into a multi-component format.
Changes in Ti K-edge X-ray absorption fine structure (XAFS) spectra of lithium titanium oxide (LTO) during the charge discharge cycle of lithium ion battery were investigated by using a specially designed cell for in situ X-ray measurement. Thought LTO is famous for zero-strain lattice during the charge/discharge cycle, the significant spectral changes might be attributed to Li migration in the lattice. The experimental results were compared with the theoretical simulation, and the spectral changes were caused both by the slight changes in oxygen position parameter that affected titanium neighbors and Li migration.
Owing to its high conductivity, graphene holds promise as an electrode for energy devices such as batteries and photovoltaics. However, to this end, the work function and doping levels in graphene need to be precisely tuned. One promising route for modifying graphene’s electronic properties is via controlled covalent electrochemical grafting of molecules. We show that by employing diaryliodonium salts instead of the commonly used diazonium salts, spontaneous functionalization is avoided. This allows for precise tuning of the grafting density. By employing bis(4-nitrophenyl)iodonium(III) tetrafluoroborate (DNP) salt calibration curves, the surface functionalization density (coverage) of glassy carbon was controlled using cyclic voltammetry in varying salt concentrations. These electro-grafting conditions and calibration curves translated directly over to modifying single layer epitaxial graphene substrates (grown on insulating 6H-SiC (0001)). In addition to quantifying the functionalization densities using electrochemical methods, samples with low grafting densities were characterized by low-temperature scanning tunneling microscopy (LT-STM). We show that the use of buffer-layer free graphene substrates is required for clear observation of the nitrophenyl modifications. Atomically-resolved STM images of single site modifications were obtained, showing no preferential grafting at defect sites or SiC step edges as supposed previously in the literature. Most of the grafts exhibit threefold symmetry, but occasional extended modifications (larger than 4nm) were observed as well.
Nanostructured MnO2/nitrogen doped graphene (MnO2/N-RGO) hybrids were synthesized by a facile and economic method at low temperature with ammonia pretreatment. Characterizations show nitrogen atoms were embedded into graphene lattice during pretreatment followed by MnO2 nanowires anchored onto graphene flakes. Compared with MnO2/graphene (MnO2/RGO) hybrids, the novel hybrids exhibited higher capacitance value and enhanced cyclic stability. At a current density of 2mAcm−2, the capacitance of as-obtained hybrids was up to 275.2Fg−1 and retained 98.3% of initial capacitances after 1000 cycles. These results illustrate that ammonia pretreatment is effective for nitrogen atom doping and the hybrids are potential as electrode materials for supercapacitors.
Bioinspired nanogenerators based on vertically aligned phage nanopillars are inceptively demonstrated. Vertically aligned phage nanopillars enable not only a high piezoelectric response but also a tuneable piezoelectricity. Piezoelectricity is also modulated by tuning of the protein's dipoles in each phage. The sufficient electrical power from phage nanopillars thus holds promise for the development of self-powered implantable and wearable electronics.
The 12V overcharge instability of the LiCoO2 cathode material was improved by the physical blending it with LiNi0.8Co0.1Mn0.1O2. Even though a Li-ion cell containing a LiCoO2 cathode did not exhibit thermal runaway at 12V at the 1C overcharging rate, it showed thermal runaway at the 2C overcharging rate, and the cell surface temperature reached more than 400°C. However, the LiCoO2 cell containing 40, 50, and 60wt.% LiNi0.8Co0.1Mn0.1O2 did not exhibit thermal runaway at the 2C overcharging rate. In conclusion, 60wt.% LiNi0.8Co0.1Mn0.1O2 in the LiCoO2 cathode showed the lowest cell surface temperature of <90°C even at a 3C overcharging rate.
The development of Na secondary batteries that exhibit both sustainability and high energy density as potential successors to lithium-ion batteries for certain large-scale applications has received considerable research interest in recent years. However, although the importance of the electrolyte in such systems has long been largely overlooked, it is becoming increasingly recognized as a key consideration (along with the electrode material) for the non-incremental improvement of Na secondary batteries. Among the candidate electrolytes in this context, ionic liquids (ILs), which are liquids consisting entirely of ions, offer many unique advantages. In this review, the fundamental properties of ILs and the design strategies employed to facilitate their application in batteries are introduced. Comprehensive summaries of the recent advances in the development of positive and negative electrode materials for Na secondary batteries are then presented. Most of the IL-based systems discussed exhibit remarkably enhanced performances compared to those of batteries based on conventional electrolytes. Furthermore, reversible capacity, rate capability, recyclability, and coulombic efficiency are synergistically enhanced by combining IL electrolytes and elevated temperature conditions. Finally, the practical prospects and future challenges associated with the development of electrode materials fabricated from cheap, abundant elements; the efficient utilisation of Na metal as a negative electrode material; and considerations related to the solid–electrolyte interphase are also discussed.
Nowadays LiFePO4 cathode develops rapidly for its advantages of long life span, low cost and non-toxicity, especially in electrical vehicle markets. Because of its stable olivine structure, LiFePO4 is difficult to be recycled by the conventional hydrometallurgical processes as for LiCoO2 or LiNixCoyMnzO2. Pyrometallurgical processes consume much energy and release toxic gases. Herein, an effective room-temperature process based on the mechanochemical treatment is proposed to extract metals from LiFePO4. Spent LiFePO4 is co-grinded with low-cost citric acid agent in a ball mill. After grinding, the mixture is dissolved in deionized water and filtrated. With addition of H2O2, the extraction efficiency of Li reaches as high as 99.35%. Conversely, Fe is hardly extracted with a low extraction efficiency of only 3.86%, indicating a selective recovery of valuable Li element. In addition, when H2O is used instead of H2O2, the mechanochemical reaction changes and the extraction efficiencies of Li and Fe at optimal conditions reach 97.82% and 95.62%, respectively. The Fe impurity is removed as Fe(OH)3 precipitation by adding NaOH, and Li is recycled as Li2CO3 after reaction with saturated Na2CO3 at 95 °C. This simple and easily-operated process has little negative impact on the environment and has great potential in industrial applications.
La0.67Mg0.33Ni2.5Co0.5 alloys were prepared by induction melting followed by different annealing treatments (1023, 1073, 1123 and 1173K) for 24h. Alloy structure and electrochemical properties of different annealed alloys have been studied systematically by X-ray diffraction (XRD), scanning electron microscope (SEM) and electrochemical experiments. Alloy structure analyses show that all of the alloys consisted of complex phases such as (La, Mg)(Ni, Co)3 phase (PuNi3-type, SG: R-3 m), (La, Mg)2(Ni, Co)7 phase (Ce2Ni7-type, SG: P63/mmc), LaMg(Ni, Co)4 phase (MgCu4Sn-type, SG: F-4 3 m) and La(Ni, Co)5 phase (CaCu5-type, SG:P6/mmm). One thousand one hundred and twenty-three kelvin benefited formation of (La, Mg)(Ni, Co)3 phase best. Main phase in alloy became (La, Mg)2(Ni, Co)7 phase at 1173K annealing treatment. Electrochemical experiments show that absorption/desorption plateau became flatter and wider after annealing treatment, that all of the alloy electrodes exhibited good activation characteristics, that annealing treatment improved discharge capacities of alloy electrodes from 315mAhg−1 (as-cast) to 402.5mAhg−1 (1173K). At the same time, cyclic stability of alloy electrodes was also improved with rise of annealing temperature, especially for alloy electrode (S70 =92.9%) with main phase (La, Mg)2(Ni, Co)7 at 1173K. As (La, Mg)(Ni, Co)3 phase in alloys increased, high rate dischargeability characteristics were deteriorated. However, alloy electrode with main phase (La, Mg)2(Ni, Co)7 exhibited the best kinetic characteristics. All experiments imply that alloy electrode with main phase (La, Mg)2(Ni, Co)7 possessed excellent overall electrochemical properties.
Hierarchical porous carbons (HPCs) with high specific surface area are synthesized by a simple self-template strategy from the alage Enteromorpha prolifera (E. prolifera). The surface of the dried E. prolifera biomass contains carboxylic/hydroxyl groups and mineral salts, which can cooperate together to form metal-organic framework complexes. These salts and complexes can serve as self-templates to produce hierarchical porous structures during the activation process. The activated carbon is used to make an HPC electrode and the electrochemical properties of the supercapacitor fabricated from this HPC electrode are characterized by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy in 6 mol L−1 KOH solution. The specific capacitance is 210 F g−1 at a current density of 3 A g−1. The good capacitive behavior is attributed to the high BET-surface area of 3332 m2 g−1, large pore volume of 2.46 cm3 g−1 and hierarchical porous structure (an abundance of interconnected mesopores, macropores and micropores). These results demonstrate that E. prolifera is a promising precursor to prepare high performance and low cost electrode materials for electrical double layer capacitors (EDLCs).
Anodes for lithium-ion cells were constructed from three types of natural graphite, two coated spherical and one flaky. Anode samples were compressed from 0 to 300kg/cm2 and cycled in half-cells to study the relations between anode density, SEI formation and anode cyclability. The C/25 formation of the SEI layer was found to depend on the nature of the graphite and the anode density. Compression of the uncoated graphite lead to an increased conductivity, but only slight improvements in the efficiency of the formation process. Compression of the anodes made from the amorphous-carbon-coated graphites greatly improved both the reversible capacity and first-cycle efficiency. In addition, the fraction of the irreversible charge associated with the surface of the graphite increased with compression, from both an increase in the electrolyte contact as well as compression of the amorphous layer. The cyclability of all of the anodes tended to improve with compression. This suggests that it is the improvement in the conductivity of the anode plays more of a role in the improvement in the cyclability than the formation process.
Under the current wave of international responses to the growing threat of climate change, Taiwan cannot afford to step back from its goal of advancing its renewable energy, strengthening its energy self sufficiency and energy security. This paper will first analyze the high level dependency structure of Taiwan's energy demands; then we will explore Taiwan current situation in terms of renewable energy development; furthermore from an overview of the course of changes and development in Taiwan's energy policy, highlight the commitment to and aims of Taiwan's Renewable Energy Development, made by the government at the Annual National Energy Conference. Fourth, we shall analyse technological R&D, incentives, taxes, market reforms and other related policy tools. Fifth, in light of public announcements and budgets set in recent years for Taiwan's renewable energy research plan, highlight main strategies being given impetus by the government. Sixth, the author will discuss the implications of recent significant legal reforms to the development of renewable energy in Taiwan and from the correlating aspects of industrial structures and energy consumption, take the first steps in emphasizing the urgent need for adjustments to be made to Taiwan's industrial structure. Finally, this paper will conclude by examining current policies, legislation and strategies which are in place to promote this area in Taiwan and discuss the potential competitiveness and future scenarios which the development of Renewable Energy could mean for Taiwan.
ABSTRACT There is significant interest in using Li-ion batteries as the power source for electric vehicle (EV) applications. Li-ion batteries are, however, sensitive to their thermal environment and it is important to control their operating temperature in order to meet the safety, reliability, and performance requirements. Computer aided engineering (CAE) is used extensively in the automotive industry to assist in the design and development of vehicles. This paper describes an analytical approach that Tata Motors European Technical Centre (TMETC) has developed using existing tools and new techniques in order to support the design of a battery thermal management system.
Antimony/carbon (Sb/C) composite fibers with Sb nanoparticles uniformly dispersed in carbon matrix have been successfully fabricated by a facile spinning approach and the subsequent calcination in argon flux. As the anode materials of lithium-ion battery, experimental results reveal that the increase of Sb concentration enhanced the lithium-ion storage capacity and worsened the cycling performance. Carbon matrix could efficiently buffer the volume change and maintain the integrity of electrode during the lithiation/delithiation, improving the cycling capability. Among the Sb/C composite fibers, the sample (Sb5) with appropriate carbon content of ca. 50.1 wt% achieves a reversible capacity of 315.9 mAh g−1 after 100 cycles at a current density of 100mAg−1 and the capacities of 464.4, 395.4, 328, 246.2 and 149.8 mAh g−1 at 100, 200, 400, 800 and 1600mAg−1, respectively. Electrochemical impedance spectroscopy (EIS) results indicate that Sb5 shows more superior charge transfer rate and Li-ion diffusion ability than the samples with high Sb concentration (Sb6) or carbon concentration (Sb4), finally resulting in better capacity retention and rate performance.
Metal cobaltites have promising electrochemical properties for their application as an energy storage medium. In this paper, usefulness of MgCo2O4 as a supercapacitor electrode is demonstrated and compared its performance with two other cobaltites, MnCo2O4 and CuCo2O4. The materials are synthesized using molten salt method and characterized by X-ray diffraction, scanning electron microscopy, BET surface area, cyclic voltammetry, galvanostatic charge–discharge cycling, and electrochemical impedance spectroscopy techniques. The MgCo2O4 electrodes show superior charge storage properties in 3M LiOH among a diverse choice of electrolytes. The MgCo2O4 show higher theoretical (∼3122F/g) and practically achieved capacitance (∼320F/g), larger coulombic efficiency, and cycling stability than the other two; therefore, it could be developed as a low-cost energy storage medium.
In this paper, a novel route using lithium polyacrylate (PAALi) as dual-functional lithium source was developed to produce layered oxide cathodes. The PAALi was in-situ polymerized on the surface of Ni1/3Co1/3Mn1/3(OH)2 precursor. By means of spray drying, spherical powders composed of PAALi wrapped around the precursor were prepared. The organic compound PAALi can function as a particle size control agent as well as the highly dispersed lithium source in the proposed route. It can transform to carbon coating layers during pre-heat treatment at 450°C under inert atmosphere. Those carbon coating layers not only significantly reduce agglomeration of particles and limit growth of the particle size, but also provide enough inner voids and paths after the subsequent sintering at 900°C. The produced layered cathodes can deliver capacity retention of 84.4% after 200 cycles at 1C and a capacity of 110.5mAhg−1 at 10C. In comparison, the sample prepared with traditional lithium source only delivers capacity retention of 63.0% after 200 cycles at 1C and 70.9mAhg−1 at 10C. The proposed route using PAALi as lithium source is potentially generalized to a broad application in the preparation of high-performance electrode materials.
A hybrid renewable energy system (HRES) uses several kinds of sources, including wind and solar, to make better use of the natural resources in standalone applications. A common application of HRES is in remote communities, where interconnected electrical grid is unreachable due to economics and physical reasons. Due to the long distance and difficult access to these isolated areas, electrical generation systems used in these applications must be reliable. And the reliability of the system, especially the inverter used to regulate the AC voltage, is one of the main problems associated to these systems, and it is responsible for the lack of confidence in renewable systems at several locations in Brazil. This paper shows the results of using renewable hybrid systems specially designed for isolated areas, focusing attention on reliability, efficiency and expansion flexibility. It presents the system description, mode of operation, inverter design, and experimental results measured in a pilot plant located in Lençóis Island, a small isolated community in the north region of Brazil.
Interdigitated on-chip micro-supercapacitors based on Carbide Derived Carbon (CDC) films were fabricated and tested. A titanium carbide (TiC) film was patterned and treated with chlorine to obtain a TiC derived carbon (TiC–CDC) film, followed by the deposition of two types of current collectors (Ti/Au and Al) using standard micro-fabrication processes. CDC based micro-supercapacitors were electrochemically characterized by cyclic voltammetry and impedance spectroscopy using a 1 M tetraethylammonium tetrafluoroborate, NEt4BF4, in propylene carbonate (PC) electrolyte. A capacitance of 0.78 mF for the device and 1.5 mF cm−2 as the specific capacitance for the footprint of the device was measured for a 2 V potential range at 100 mV s−1. A specific energy of 3.0 mJ cm−2 and a specific power of 84 mW cm−2 were calculated for the devices. These devices provide a pathway for fabricating pure carbon-based micro-supercapacitors by micro-fabrication, and can be used for powering micro-electromechanical systems (MEMS) and electronic devices.
Lead-acid batteries are widely used in conventional internal-combustion-engined vehicles and in some electric vehicles. In order to improve the longevity, performance, reliability, density and economics of the batteries, a precise state-of-charge (SoC) estimation is required. The Kalman filter is one of the techniques used to determine the SoC. This filter assumes an a priori knowledge of the process and measurement noise covariance values. Estimation errors can be large or even divergent when incorrect a priori covariance values are utilized. These estimation errors can be reduced by using the adaptive Kalman filter, which adaptively modifies the covariance. In this study, an adaptive extended Kalman filter (AEKF) method is used to estimate the SoC. The AEKF can reduce the SoC estimation error, making it more reliable than using a priori process and measurement noise covariance values.