batterydata/paper-abstracts huggingface dataset:
This study proposes a dynamic impedance method to estimate the state of charge (SOC) and a projection method to estimate the state of health (SOH) of lithium-ion batteries. We defined changes in voltage over changes in current during charging and discharging processes as the dynamic impedance, which was then used to calculate SOC. The proposed methods do not require initial values, and dynamic impedance provides a more accurate reflection of the electrical characteristics of batteries compared to conventional estimation methods. This approach also enables calculations in real-time. The SOH of batteries degenerates with age, which also alters the characteristics of dynamic impedance. The proposed projection method determines the SOH according to the rate of change in dynamic impedance with respect to the SOC. We also developed a real-time SOC and SOH estimation system, combining a microcontroller and estimation methods with a battery management system (BMS). The BMS retrieves the data required for SOC and SOH estimation and includes various protection mechanisms designed to extend the lifespan of the battery. The hardware structure and the software procedure of the developed system are described in detail. We also present the results of experiments verifying the accuracy and feasibility of the proposed estimation methods.
Chemical composition modifications of a Laves phase-related BCC solid solution base alloy, Ti15.6Zr2.1V44Cr11.2Mn6.9Fe2.7Co1.4Ni15.7Al0.3, were investigated in order to study the function of each constituent element on the structural, gaseous phase and electrochemical hydrogen storage properties of these alloys. In general, removal of Fe and decrease in V-content in exchange for higher Ni-content were found to improve both the electrochemical capacity and high-rate dischargeability, which are related to the decrease in C14-content and increase in TiNi-content. However, total elimination of the C14 phase by removal of Zr resulted in a reduced discharge capacity, a prolonged activation period, and a less catalytic surface for electrochemical reaction. Besides the BCC and C14 phases, the TiNi phase was also found in every alloy in this study, contributing positively to the bulk diffusion of hydrogen while hindering the surface electrochemical reaction.
In this study, by using commercial melamine foam as a starting material, we report a facile method to prepare N-doped carbon framework loaded with graphene (NCF-G), in which graphene nanosheets are homogeneously coated on the N-doped carbon framework. After sulfur is infused into this composite, the electrode delivers an initial capacity of 1,359.7mA h g−1 at 0.1C (1st cycle), and maintains a specific capacity of 629.3mA h g−1 for 150 cycles at 0.5C for lithium-sulfur batteries. The improved electrochemical performances are attributed to the capping effect exerted by N-doping for polysulfides and high electrical conductivity of the carbon framework with highly conductive graphene.
The price of the cathode active materials in lithium ion batteries is a key cost driver and thus significantly impacts consumer adoption of devices that utilize large energy storage contents (e.g. electric vehicles). A process model has been developed and used to study the production process of a common lithium-ion cathode material, lithiated nickel manganese cobalt oxide, using the co-precipitation method. The process was simulated for a plant producing 6500 kg day−1. The results indicate that the process will consume approximately 4 kWh kgNMC −1 of energy, 15 L kgNMC −1 of process water, and cost $23 to produce a kg of Li-NMC333. The calculations were extended to compare the production cost using two co-precipitation reactions (with Na2CO3 and NaOH), and similar cathode active materials such as lithium manganese oxide and lithium nickel cobalt aluminum oxide. A combination of cost saving opportunities show the possibility to reduce the cost of the cathode material by 19%.
Nano-sized SiO x is synthesized by an evaporation and condensation process using induction melting with the injection of various mixed gases. In particular, the effects of O2 gas on their microstructures and electrochemical properties are investigated. The x-values of the synthesized SiO x can be controlled from 1.18 to 1.83 by varying the O2/Ar ratios in the injected gas. A micro-structural analysis reveals that mixture of nanoparticles and nanowires is formed and that the relative amount of nanowire decreases with an increase of the oxygen contents in the injected gas. When x is low, crystalline Si is formed, but this phase disappears when x exceeds 1.28. From the electrochemical analysis of the various SiO x powders, the Initial Columbic Efficiency (ICE) decreases with the increase in the x-values – largely due to the oxidation of Li-ions such as Li2O and Li4SiO4. Cycle stability, however, is improved with the increase of the x-values, indicating that strain and stress during insertion and extraction of Li-ions are properly released due to the oxide buffer around the Si as well as the nano-sized structure. When x = 1.18, a specific capacity of 660 mAh g−1 with a columbic efficiency of 99.8% at the 50th cycle is obtained.
Purpose To investigate the effect of ‘training’ the patients' near vision and motivating them towards a spectacle-independent outcome on near vision performance in pseudophakic patients with standard intraocular lens (IOL). Design Prospective randomized, controlled, examiner-masked clinical trial. Methods Eighty eyes of 40 patients with standard cataract surgery were randomly assigned to a “motivated” or “control” group. In the motivated group, subjects were told that they are taking part in a special protocol to improve their near-reading ability after cataract surgery and were instructed not to use reading glasses for at least three months and received cycloplegic eye drops for 10 days after surgery. Follow-up examinations at three months included best-corrected distance visual acuity (VA), distance-corrected near VA, best-corrected near VA, assessment of the defocus curve, and reading speed, as well as pilocarpine-, cyclopentolate- and nearpoint-induced IOL shift assessed with partial coherence interferometry. Additionally, a questionnaire evaluating patients' postoperative satisfaction, independency of reading glasses, and daily-life performance without glasses was carried out three months and one year postoperatively. Results No difference in reading ability and IOL shift between “motivated” and “control” patients could be detected. However, the motivated patients were less dependent on reading glasses and their ability to be able to perform activities of daily life without glasses was significantly better. Conclusion There was no improvement of ciliary body function in pseudophakic patients with a special training protocol. However, near vision training made patients more independent of reading glasses.
The development of nonaqueous and surfactant-free sol–gel routes to metal oxides has become a very active area within the broad field of nanoparticle research, opening up great opportunities to access a wide variety of binary, ternary and doped metal oxide nanoparticles with high crystallinity and well-defined particle morphologies — important parameters towards their application in electrochemistry, (photo)catalysis or gas sensing. Extension to other classes of inorganic nanomaterials such as nitrides and sulfides and energy optimization of the processes by using dielectric heating represents two promising research directions. Remaining future challenges are not only the development of rational synthesis strategies, nanoparticle processing, assembly and patterning into functional and integrated structures, but also the optimization of the synthesis protocol with respect to energy efficiency and waste management. This review aims at giving both an overview of the current state of research as well as a discussion of the perspectives in the area of nonaqueous and/or non-hydrolytic sol–gel technology for the synthesis, processing and application of inorganic nanomaterials.
The mechanism of the positive plate charge in pulse regime was studied in model lead-acid cells with one positive and two negative plates (8Ah each) and Ag/Ag2SO4 reference electrodes. The results showed that the evolution of the electrode potential is much slower on the positive plate than on the negative plate. Regardless of this fact, the calculated capacitive current of charge and self-discharge of the electrochemical double layer (EDL) during the “ON” and “OFF” half-periods of the pulse current square waves is comparable with the charge current amplitude. The result is due to the high values of the EDL on the surface of the lead dioxide active material. The influence of different factors like state of charge, state of health, pulse frequency, current amplitude and open circuit stay before the polarization was discussed. The previously determined optimal frequency of 1Hz was associated with a maximum in the average double layer current on frequency dependence. The average double layer current is also maximal at SOC between 75 and 100%. The exchange of the constant current polarization with pulse polarization does not change substantially the mechanism and the overvoltage of the oxygen evolution reaction on the positive plate. The mechanism of the self-discharge of the EDL was also estimated analyzing long-time PPP transients (up to 2h). It was found that when the PPP is lower than 1.2V the preferred mechanism of EDL self-discharge is by coupling with the lead sulphate oxidation reaction. At higher values of PPP the EDL self-discharge happens via oxygen evolution. The high faradic efficiency of the pulse charge is due to the chemical oxidation of the Pb(II) ions by the O atoms and OH radicals formed at the oxygen evolution both during the “ON” and “OFF” periods.
The interest in research and development of solar PV and thermal applications has been growing fast in China due to climate change concerns and environmental protection in addition to energy shortage. A number of research achievements have been put into practice, and a promising solar energy market has been formed. Among them, solar water heaters (SWHs), photovoltaic (PV) cells, PV power generation, and PV/thermal (PV/T) systems have gained the most popularity. This work reviews the solar energy resources, PV technology and applications, development of solar thermal applications, and the research and development of PV/T systems in China. The results show that China's renewable energy applications have grown rapidly in the past 10 years, and that China has become the biggest producer of PV cells and SWHs in the world. In 2011, China's PV products held 42% and the SWH cumulative installations constituted about 2/3 of globe amount. One trend in SWH development in China is the integration of the SWHs with the building structure, and PV/T hot water systems are expected to dominate solar applications in buildings. Problems lying in China's PV industry are pointed out, and suggestions for solving the problems are proposed.
RFC combined with solar photovoltaic (PV) array is the advanced technologic solution for on-board energy storage, e.g. land, sky, stratosphere and aerospace applications, due to its potential of achieving high specific energy. This paper focuses on mass modeling and calculation for a RFC system consisting of discrete electrochemical cell stacks (fuel cell and electrolyzer), together with fuel storage, a PV array, and a radiator. A nonlinear constrained optimization procedure is used to minimize the entire system mass, as well as to study the effect of operating conditions (e.g. current densities of fuel cell and electrolyzer) on the system mass. According to the state-of-the-art specific power of both electrochemical stacks, an energy storage system has been designed for the conditions of stratosphere applications and a rated power output of 12kW. The calculation results show that the optimization of the current density of both stacks is of importance in designing the light weight on-board energy system.
The effects of the styrene–butadiene rubber (SBR) to sodium carboxymethyl cellulose (CMC) blending ratio of the water-based SBR/CMC binder on the dispersion and the physical and electrochemical properties of LiCoO2 electrodes are studied. Based on the results of dispersion analyses, it is determined that CMC is efficient in dispersing LiCoO2, and the dispersion of the LiCoO2 electrode slurry becomes better when the fraction of SBR in the binder is decreased. Based on physical and electrochemical measurements, however, decreasing the SBR fraction makes the distribution of the binder in the dried electrode sheet less uniform, which results in decreased adhesion strength and increased surface resistance of the electrode sheets. In addition, this study reveals that the binder distribution has a greater influence on the electrical and electrochemical properties of the LiCoO2 electrodes than the dispersion of cathode powders has.
Solar desalination systems are approaching technical and cost viability for producing fresh-water, a commodity of equal importance to energy in many arid and coastal regions worldwide. Solar photovoltaics (PV) represent an ideal, clean alternative to fossil fuels, especially for remote communities such as grid-limited villages or isolated islands. These applications for water production in remote areas are the first to be nearing cost-competitiveness due to decreasing PV prices and increasing fossil fuel prices over the last five years. The electricity produced from PV systems for desalination applications can be used for electro-mechanical devices such as pumps or in direct-current (DC) devices. Reverse osmosis (RO) and electrodialysis (ED) desalination units are the most favorable alternatives to be coupled with PV systems. RO usually operates on alternating current (AC) for the pumps, thus requiring a DC/AC inverter. In contrast, electrodialysis uses DC for the electrodes at the cell stack, and hence, it can use the energy supplied from the PV panels with some minor power conditioning. Energy storage is critical and batteries are required for sustained operation. In this paper, we discuss the operational features and system designs of typical PV-RO and PV-ED systems in terms of their suitability and optimization for PV operation. For PV-RO and PV-ED systems, we evaluate their electricity need, capital and operational costs, and fresh-water production costs. We cover ongoing and projected research and development activities, with estimates of their potential economics. We discuss the feasibility of future solar desalination based on expected (or predicted) improvements in technology of the desalination and PV systems. Examples are provided for Middle East and other parts of the World.
Recently, Ti3C2Tx MXene has drawn enormous attentions in Li-ion batteries (LIBs) due to its two dimensional (2D) open architecture, superior conductivity and low Li+ diffusion barrier. However, further applications of Ti3C2Tx MXene are seriously limited by its moderate capacities. Herein, we fabricate SnOx@Ti3C2 composites, where ultrathin SnOx nanosheets (NSs) of ∼5 nm in thickness are loaded uniformly on the interlayers and/or surfaces of Ti3C2 matrix, through a facile hydrothermal method towards efficient lithium storage. Benefiting from ultrathin feature and large capacity of SnOx NSs, metallic conductivity of Ti3C2 matrix, strong affinity between SnOx and Ti3C2, the resulted SnOx@Ti3C2 composites exhibit long-duration cycling stability and superior rate behaviors. Competitively, a large reversible capacity of ∼540 mAh g−1 still can be kept even after 1000 cycles at a current rate of 500 mA g−1. Corresponding quantitative analysis reveals that capacitive and diffusion-controlled behaviors co-contribute to striking Li+ storage properties of the hybrid anodes, wherein the former dominates. This work demonstrates that the MXene-based materials hold a significant promising for advanced next-generation LIBs.
High Performance (HP) battery electric vehicle (BEV) and racing applications represent significantly different use cases than those associated with conventional consumer vehicles and road driving. The differences between HP use cases and the duty-cycles embodied within established battery test standards will lead to unrepresentative estimates for battery life and performance within a HP application. A strategic requirement exists to define a methodology that may be used to create a representative HP duty-cycle. Within this paper two methods HP duty-cycle design are evaluated and validated. Extensive simulation results into the electrical performance and heat generation within the battery highlight that the new HP duty-cycles provide a more representative duty-cycle compared to traditional battery test standards. The ability to more accurately predict the performance requirements for the battery system within this emerging and strategically important BEV sector will support a range of engineering functions. In addition, the ability to more accurately define the use-case for a HP-BEV will underpin ongoing experimentation and mathematical modelling to quantify the associated cell ageing and degradation that may occur within HP vehicle applications.
The aim of this study was to explore whether change in verbal memory with time in patients with epilepsy is influenced by performance on tasks assessing verbal cognition or attention/processing speed. Thirty-six patients and twenty-five healthy controls were tested twice with median retest intervals of 4.8 and 3.1 years, respectively. Aspects of verbal memory, verbal cognition, and attention/processing speed were assessed. Decline in one verbal memory variable (Cronholm–Molander Memory Test Paired Associates—Delayed Recall) was the strongest correlate of epilepsy. The second strongest correlate was a decrease in one attention/processing speed variable (Digit Symbol). The relationship between decline in verbal memory and epilepsy was not influenced by the decline in attention/processing speed, and the results did not support the notion that limited mental reserves as reflected in impaired verbal cognition or attention/processing speed can explain the relationship between verbal memory and epilepsy.
A new carbon supported lithium-copper cathode catalyst (gel@LiCu) is composed of activated carbon (@) supported gel, LiNO3 and CuCl2 mixture is investigated in the oxygen reduction reaction. The gel@LiCu cathode, which is selected from different configurations of electrodes, is found to have the best material for the cathode. The molar ratio of lithium-copper (1.0:1.5) and the amount of glycine given in terms of grams are determined in order to find the most active material. The catalytic activity of the gel@LiCu electrode is evaluated by cyclic voltammetry, potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The morphology and the phase structure of the gel@LiCu electrode are characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) spectrometer. The catalyst shows good catalytic activity for oxygen reduction reaction (ORR), as well as oxygen evolution reaction (OER).
Selecting an appropriate software tool for a particular energy-management system is a challenging task as there is little information available and several software tools to pick from. Each tool has its own strengths and limitations, and making a right choice is critical for accurate and feasible analyses. This paper reviews more than one hundred simulation software packages that are useful for residential-energy-management system analysis. The tools are analyzed based on the conventional and CEN-CENELEC-ETSI Smart Grid Reference Architecture. Additionally, tools’ availability, sources, typical applications, strengths, and limitations are discussed. A case study on residential energy management and optimization is carried out to show the strengths and limitations of a certain computational tool. It is observed that none of the tools cover all the applications of residential energy systems, however necessary information is provided to help researchers to choose the right tools to meet specific objectives.
The electrochemical and thermal properties of carbon microbeads (CMB) electrodes with the hybrid electrolytes consisting of varying proportions of N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13TFSI) and alkyl-carbonate organic solvent are investigated. Particularly, the interfacial properties of CMB/hybrid electrolytes are explored by means of morphologic observations and spectroscopic technologies. It is found that, after the addition of lithium salt to pure PP13TFSI, the decomposition of more TFSI− anions possibly is a new reason for the increased sharply interfacial resistance. By contrast, the hybrid electrolytes with 50–70wt% alkyl-carbonate co-solvents have advantages of high ionic conductivity and excellent thermal safety combined. Another even more important is that, due to theirs low viscosity and assistant CMB passivation, they have the superiorities in Li+ mobility, particle wettability and solid electrolyte interphase (SEI) film etc., and then show the improved charge–discharge performances. These results clearly prove the advantage of the use of hybrid electrolytes on the performance of the CMB electrode.
Objective Maximum seizure control, preservation of cognition, and prevention of developmental hindrance are major aims of the pharmacological treatment of children and adolescents with epilepsy. Herewith we introduce the junior version of EpiTrack, a 12- to 15-minute screening test for monitoring the cognitive effects of antiepileptic drug treatment in children and adolescents aged 6 to 18. Methods The test, which comprises six subtests (Speed, Flexibility, Planning, Response Inhibition, Word Fluency, Working Memory), was administered to 277 children and adolescents aged 6–18years, 111 of whom were retested after an interval of 3months. For the first clinical validation, 155 patients (46% idiopathic/benign, 62% seizure free) were evaluated. Results Standardization and correction for age resulted in a mean score of 33±2 points, which was no longer correlated with age (r =0.005). The retest practice effect was 0.7±2 points, and the reliability r tt =0.78. Factor analysis indicated one executive factor in controls and patients. In the epilepsy group, 50% of the patients were impaired (controls 14%). Number of antiepileptic drugs, use/no use of individual drugs, type of epilepsy, earlier age at onset, generalized tonic-clonic seizures, and history of febrile seizures made a difference in test performance. For patients and controls, EpiTrack scores reflected parents’ performance ratings and the children's needs for extra education. Conclusion The junior version of EpiTrack appears to be a valid and reliable screening tool for the assessment of executive functions in children and adolescents. Future studies with a repeated measurement design must show how well this tool is suited for the tracking of cognitive effects of antiepileptic drug treatment.
To meet the design requirements for high-rate battery electrodes, self-supporting hierarchical rGO@Ni nanosheet@Co3O4 nanowire array film with light weight is synthesized via a series of controllable fabrication processes. Due to modifying the highly conductive nickel nanosheets onto the surface of rGO film, the energy storage performance of this hybrid film is enhanced, especially in rate capability. The whole high-rate battery, which is fabricated by using this film as the positive electrode, manifests the maximum energy density of 20.3 Wh kg−1 at a power density of 326 W kg−1 along with excellent capacity retention of 81.4% after 5000 cycles. Therefore, the rGO-Ni-Co3O4 hybrid film is a promising electrode material for flexible long-life cycling high-rate batteries.