batterydata/paper-abstracts huggingface dataset:
Electrification of villages from the main grid leads to large investments and losses, and this forms the basis of decentralized Hybrid Energy System. In order to evaluate the techno-economic performance of hybrid energy system for remote rural area electrification, a mixed integer linear mathematical programming model (time-series) has been developed to determine the optimal operation, optimal configuration including the assessment of the economic penetration levels of photovoltaic array area, and cost optimization for a hybrid energy generation system consisting of small/micro hydro based power generation, biogas based power generation, biomass (fuelwood) based power generation, photovoltaic array, a battery bank and a fossil fuel generator. An optimum control algorithm written in C++, based on combined dispatch strategy, allowing easy handling of the models and data of hybrid energy system components is presented. A special feature of the proposed model is that a cost constant (cost/unit) for each of the proposed resource is introduced in the cost objective function in such a way that resources with lesser unit cost share the greater of the total energy demand in an attempt to optimize the objective function. To demonstrate the use of model and algorithm, a case study for a rural remote area is also presented.
In this work, carbon-coated hierarchical acanthosphere-like Li4Ti5O12 microspheres (denoted as AM-LTO) were prepared via a two-step hydrothermal process with low-cost glucose as the organic carbon source. The hierarchical porous microspheres had open structures with diameters of 4–6 μm, which consisted of a bunch of willow leaf-like nanosheets. Each nanosheet was comprised of Li4Ti5O12 nanoparticles that are 20 nm in size and coated by a thin carbon layer. When applied as the anode material for lithium-ion batteries (LIBs), the AM-LTO presented outstanding rate and cycling performance due to its unique morphologies. A high capacity of 145.6 mAh g−1 was achieved for AM-LTO at a rate of 40C (1C = 175 mAh g−1). In contrast, the sample synthesized without glucose as carbon source (denoted as S-LTO) experienced an obvious structural collapse during the hydrothermal reaction and presented a specific capacity of only 67 mAh g−1 at 1C, which further decreased to 14 mAh g−1 at 40C. Further morphological growth of the acanthosphere-like Li4Ti5O12 microspheres and their excellent performance as an anode in LIBs were also discussed in this work.
Worldwide, over 1.1 billion people have no access to electricity. The consequences for the affected people include health hazards from fuels used for lighting, limits to learning when it gets dark, a short productive day and high expenditures on lighting alternatives. Since 85% of affected people live in rural areas in developing countries, increasing access to electricity through grid supply is logistically and financially challenging. As a potential solution to this issue off-grid solar chargers have been gaining popularity. This technology is under continuous development to achieve lower costs, faster battery charge and more electricity generation to prolong light hours. This review contains a comprehensive analysis of possible improvements to solar lights and the role solar PV concentrators can play in it. It aims to provide the reader with a critical comparison of existing solar PV concentrators and to consider the advantages and drawbacks if applied to portable solar systems used in developing countries. From this review, static nonimaging concentrators have been identified as best suited since they are easy to operate and maintain and have shown high reliability. A detailed comparison of existing static nonimaging concentrators is presented in this work and their suitability for being deployed in portable solar systems in developing countries is evaluated. It concludes that the existing designs need adjustment if to be used for this purpose. Thus, novel concentrator designs for portable solar systems for developing countries are needed to facilitate more off-grid solar power generation. It is the aim therefore of this review to stimulate more research in this field.
Lithium-ion batteries are currently the most advanced electrochemical energy storage technology due to a favourable balance of performance and cost properties. Driven by forecasted growth of the electric vehicles market, the cell production capacity for this technology is continuously being scaled up. However, the demand for better performance, particularly higher energy densities and/or lower costs, has triggered research into post-lithium-ion technologies such as solid-state lithium metal, lithium–sulfur and lithium–air batteries as well as post-lithium technologies such as sodium-ion batteries. Currently, these technologies are being intensively studied with regard to material chemistry and cell design. In this Review, we expand on the current knowledge in this field. Starting with a market outlook and an analysis of technological differences, we discuss the manufacturing processes of these technologies. For each technology, we describe anode production, cathode production, cell assembly and conditioning. We then evaluate the manufacturing compatibility of each technology with the lithium-ion production infrastructure and discuss the implications for processing costs.
A tin antimony based electrode has been synthesized in the form of nanometric particles housed into the pores of a protective, amorphous carbon matrix. Electrochemical results, obtained using this material as the working electrode in a lithium cell, suggested that the electrochemical process involves both SnSb intermetallic and Sn metal, present in the carbon matrix. Moreover, the results demonstrated that the optimized nanostructure prevents the mechanical drawbacks, associated with the volume changes during the alloying processes, which normally affect this class of materials. Finally, a lithium ion battery based on the SnSb–C electrode as the anode and lithium iron phosphate, LiFePO4, as the cathode, showed very promising performance.
Nitrogen-doped (N-doped) carbon has great potential in lithium-sulfur (Li-S) batteries, since N-doping can not only enhance the reaction activity of the cathode but also suppress the shuttle effect. Unfortunately, the N-C interface as a critical chemical active site is still short of a deep and detail understanding owing to the difficulty of interfacial structure engineering on the molecular scale. In this work, an interwoven coaxial cable network with ultrahigh nitrogen content of 9.56 wt% has been successfully fabricated through engineering a rationally designed Schiff-base chemistry. This in-situ bottom-up strategy enables the targeted heteroatom doping throughout the entire networks on molecular scale. Thus, a homogenous interface between nitrogen and carbon matrix can be achieved even at such a high doping level, which is demonstrated to play the key role in facilitating the chemical absorption of sulfur/polysulfides, and eventually improving the cycling stability of the electrode. Consequently, the composite demonstrates outstanding long cycling performance with a high specific capacity of 729 mAh g−1 after 500 cycles and a superior rate capability. The bottom-up strategy for fabricating the N-doped carbon networks will open up a new avenue for deeply understanding the critical role of interface in rational designing of N-doped carbon materials.
We construct and analyze a dynamic model of chain growth across multiple markets from an ecological perspective using computational and mathematical techniques. Our model consists of firms that possess intrinsic qualities and hedonic spatial attributes. Consumers purchase from firms based upon quality and hedonic distance. We find that the existence of chains creates an environment favorable to additional chains. In other words, chains beget chains. We also find that even though creating successful new firms becomes harder over time, chaining successful new firms becomes easier. Both phenomena result from the creation of common niches across markets.
Organic–inorganic hybrid electrolytes based on di-ureasil backbone structures by reacting poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminopropyl ether) (ED2000) with 3-(triethoxysilyl)propyl isocyanate (ICPTES), followed by co-condensation with methoxy(polyethylenoxy)propyl trimethoxysilane (MPEOP) in the presence of LiClO4 were prepared and characterized by a variety of techniques. The hybrid electrolytes showed good resistance to crystallization and excellent conductivity for use in lithium-ion batteries, as determined by differential scanning calorimetry (DSC) and impedance measurements, respectively. The temperature dependence of the ionic conductivity exhibited a VTF (Vogel–Tamman–Fulcher)-like behavior for all the compositions studied and a maximum ionic conductivity value of 6.9×10−5 Scm−1, a relatively high value for solid polymer electrolytes, was achieved at 30°C for the hybrid electrolyte with a [O]/[Li] ratio of 16. A microscopic view of the dynamic behavior of the polymer chains (13C) and the ionic species (7Li) was provided by the 1H and 7Li line widths measured from 2D 1H–13C WISE (Wideline Separation) and variable temperature 7Li static NMR, respectively, to elucidate the influence of the mobility of the polymer chains and the charge carriers on the observed ionic conductivity. The present salt-free hybrid electrolyte after plasticization with 1M LiClO4 in EC/PC solution exhibited a swelling ratio of 275% and reached an ionic conductivity value up to 8.3×10−3 Scm−1 at 30°C, which make it a good candidate for the further development of advanced rechargeable lithium-ion batteries.
Evidence suggests that elective cardiac patients are at risk of functional and psychological deterioration in the time preceding surgery. This poses a risk to successful post-operative rehabilitation. This prospective one-group pre-test, post-test evaluation was designed to assess a clinical Pre-operative Rehabilitation (PREHAB) home-based exercise programme, to optimise pre-operative physical function and frailty in patients awaiting elective Coronary Artery By-Pass Graft (CABG) or Valve Surgery.
Rechargeable metal–air batteries are widely considered as the next generation high energy density electrochemical storage devices. The performance and rechargeability of these metal–air cells are highly dependent on the positive electrode material, where oxygen reduction and evolution reactions take place. Here, for the first time, we provide a detailed account of the kinetics and rechargeability of sodium–air batteries through a series of carefully designed tests on a treated commercial carbon material. Surface area and porous structure of the positive electrode material were controlled in order to gain detailed information about the reaction kinetics of sodium–air batteries. The results indicate that discharge capacity is linearly correlated with surface area while morphology of the solid discharge product is strongly dependent on specific surface area and pore size. Furthermore, it was found that the chemical composition of discharge products as well as charging overpotential is affected by discharge reaction rate.
The α-Fe2O3/C composites have been successfully synthesized by a facile hydrothermal carbonization glucose method using pickled iron oxide red as raw materials, which is the recycled product after treating the pickling wastewater. The NaOH is used as an additive to assist carbonization of glucose to obtain the high-quality carbon coating layer. X-ray diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscope are used to characterize the structure and morphology of the samples. To characterize the surface chemical composition and bonding configuration of α-Fe2O3/C, X-ray photoelectron spectroscopy is detected. The Electrochemical properties are optimized by the orthogonal tests, revealing that the hydrothermal reaction time has the most significant influence on the electrode capacity, followed by the hydrothermal reaction temperature, the amount of glucose added and the concentration of NaOH. As anode material for lithium ion battery, the initial discharge/charge capacity of α-Fe2O3/C electrode can reach 2640.1/2151.4 mAh g−1 with initial coulomb efficiency of 81.49% at a current density of 100 mA g−1, and even after 80 cycles maintain the capacity of 1529.5 mAh g−1, which far exceeds the theoretical capacity (1007 mAh g−1) of α-Fe2O3 electrode.
Objective To explore the association between demographic factors and functional performance measures of patients with acute stroke in an inpatient rehabilitation facility (IRF) and falls during the IRF stay and to quantify the diagnostic accuracy of functional outcome measures in identifying fallers. Design Retrospective cohort study. Setting Inpatient rehabilitation facility. Participants Individuals with acute stroke admitted to hospital-based IRF (N=139). Interventions Not applicable. Main Outcome Measures Odds ratios were used to examine the relationship between fall frequency and functional outcome measures (National Institute of Stroke Scale, neglect [Item #11], Berg Balance Scale, Stroke Rehabilitation Assessment of Movement mobility and Stroke Rehabilitation Assessment of Movement lower extremity subscales [STREAM-LE], Montreal Cognitive Assessment, Dynamic Gait Index, and Stroke Impact Scale). Receiver operator characteristic analysis with area under the curve, sensitivity, specificity, and diagnostic odds ratio were used to assess the diagnostic accuracy of each functional outcome measure to distinguish patients who fell vs those who did not fall in the IRF. Results A total of 23 patients (16.2%) fell during the IRF hospitalization. Patients who did and did not fall did not differ in terms of age, sex, stroke type, or stroke location. Only the STREAM-LE was associated with falls (odds ratio, 0.93; 95% CI, 0.86-0.99). Area under the curve was 0.67 (95% CI, 0.51-0.82). With a positivity cutoff point of 12, sensitivity and specificity were 73.3% (95% CI, 54.6%-92.2%) and 50.0% (95% CI, 39.9%-59.2%), respectively. The diagnostic odds ratio was 3.4. Conclusions The STREAM-LE score at admission to IRF may identify patients with acute stroke who are more likely to fall during their stay. However, the search for measures with greater diagnostic accuracy should continue.
This article presents a new control model for the optimal next day management of a PV-battery system using a geometrical analysis method under two electricity tariff schemes. The method is visual, simple and reduces calculation times by determining the control scheme only once a day, using 24-h forecasting of PV output and demand. The optimization goal of this method is to minimize the customer’s daily expenditure on electricity from the grid. The cases studied in this work validate the effectiveness of this geometrical method which would be applicable in many countries with different tariff mechanisms. From a comparison of the control model under two tariffs, the results show that under a flat retail tariff (ReT), the battery needs only to store the surplus PV energy for later use, but under a Time-of-Use (ToU) ReT, the battery controller should optimize the battery state of charge according to the level of demand during peak and shoulder times.
A study of seepage occurring in an adit at the Nopal I uranium mine in Chihuahua, Mexico, was conducted as part of an integrated natural analogue study to evaluate the effects of infiltration and seepage on the mobilization and transport of radionuclides. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage. Field observations recorded between April 2005 and December 2006 indicate that seepage is highly heterogeneous with respect to time, location, and quantity. Seepage, precipitation, and fracture data were used to test two hypotheses: (1) that fast flow seepage is triggered by large precipitation events, and (2) that an increased abundance of fractures and/or fracture intersections leads to higher seepage volumes. A few zones in the back adit recorded elevated seepage volumes immediately following large (>20 mm/day) precipitation events, with transit times of less than 4 h through the 8-m thick rock mass. In most locations, there is a 1–6 month time lag between the onset of the rainy season and seepage, with longer times observed for the front adit. There is a less clear-cut relation between fracture abundance and seepage volume; processes such as evaporation and surface flow along the ceiling may also influence seepage.
We demonstrate that liquid-feed flame spray pyrolysis (LF-FSP) processing provides non-aggregated nanopowders that can be used immediately to tape cast, producing thin films (<100 μm) of Li+ ion conducting membranes when sintered. Glass-ceramic or sol–gel processing methods are commonly used for such but require additional high-energy milling and/or calcining to obtain powder feedstock. Li1+x+y Al x Ti2−x Si y P3−y O12 (x = 0.1, 0.3/y = 0.2, 0.4) nanopowders were prepared by LF-FSP with a primary focus on the effects of Al0.3/Si0.4 doping on conductivities. Furthermore, the effects of excess Li2O on Al0.3/Si0.4 doped materials were studied. Li1.7Al0.3Ti1.7Si0.4P2.6O12 pellets sintered to 93–94% of theoretical density and samples with varying excess Li2O contents all show superionic conductivities of 2–3 × 10−3 S cm−1 at room temperature. Li2O lowers both the crystallization temperatures and temperatures required to sinter. Total conductivities range from 2 × 10−3 to 5 × 10−2 S cm−1 in the temperature span of 25°–125 °C. Small grain sizes of 600 ± 200 nm were produced. Initial attempts to make thin films gave films with thicknesses of 52 ± 1 μm on sintering just to 1000 °C. Measured conductivities were 3–5 × 10−4 S cm−1; attributed to final densities of only ≈88%.
The past two decades have seen a tremendous surge in scientific interest in the extent to which certain types of training—be it aerobic, athletic, musical, video game, or brain trainer—can result in general enhancements in cognitive function. While there are certainly active debates regarding the results in these domains, what is perhaps more pressing is the fact that key aspects of methodology remain unsettled. Here we discuss a few of these areas including expectation effects, test–retest effects, the size of the cognitive test battery, the selection of control groups, group assignment methods, difficulties in comparing results across studies, and in interpreting null results. Specifically, our goal is to highlight points of contention as well as areas where the most commonly utilized methods could be improved upon. Furthermore, because each of the sub-areas above (aerobic training through brain training) share strong similarities in goal, theoretical framework, and experimental approach, we seek to discuss these issues from a general perspective that considers each as members of the same broad “training” domain.
Battery life is an important, yet technically challenging, issue for battery development and application. Adequately estimating battery life requires a significant amount of testing and modeling effort to validate the results. Integrated battery testing and modeling is quite feasible today to simulate battery performance, and therefore applicable to predict its life. A relatively simple equivalent-circuit model (ECM) is used in this work to show that such an integrated approach can actually lead to a high-fidelity simulation of a lithium-ion cell's performance and life. The methodology to model the cell's capacity fade during thermal aging is described to illustrate its applicability to battery calendar life prediction.
This paper introduces an online coordination approach for plug-in hybrid electric vehicles (PHEVs) charging in smart hybrid AC/DC distribution systems. The goal of the proposed method is to optimally charge the PHEVs in order to maximize the PHEV owners' satisfaction without violating the network constraints. The charging costs, which represent the PHEV owners' satisfaction in this work, are based on real-time pricing. The proposed approach includes consideration of PHEV owners' requirements, PHEV batteries' characteristics, and hybrid distribution system limitations. Moreover, a sliding window concept is introduced to facilitate managing the PHEV charging and the system interlinking converters in real-time. A 38-bus test system has been modified to include DC links and used to validate the developed online charging scheme. The test results clearly demonstrate the effectiveness of the proposed method.
We demonstrate the effects of reduced cation ordering on the electrochemical properties of LiNi0.5Mn1.5O4. LiNi0.5Mn1.5O4 is treated with nitric acid to reduce the degree of cation ordering. Nitric acid treatment induces partial oxidation of Ni2+ to Ni3+ as confirmed by X-ray photoelectron spectroscopy (XPS). Thanks to this oxidation, the 16d octahedral site in LiNi0.5Mn1.5O4 is quite void of cation ordering and its structure is partially changed to more disordered spinel engaged in Fd3m. This structural change is accompanied by significantly enhanced electrochemical performances in rate capability as well as cyclic retention. Actually, nitric acid treated LiNi0.5Mn1.5O4 can deliver about 87% of the initial capacity (129 mAh g−1) even after 100 cycles even at 55 °C.
Due to the various seasonal, monthly and daily changes in meteorological data, it is relatively difficult to find a suitable model for Photovoltaic power supply (PVPS) system. This paper deals with the modelling and simulation of a PVPS system using an Adaptive Neuro-Fuzzy Inference Scheme (ANFIS) and the proposition of a new expert configuration PVPS system. For the modelling of the PVPS system, it is required to find suitable models for its different components (ANFIS PV generator, ANFIS battery and ANFIS regulator) that could give satisfactory results under variable climatic conditions in order to test its performance and reliability. A database of measured climate data (global radiation, temperature and humidity) and electrical data (photovoltaic, battery and regulator voltage and current) of a PVPS system installed in Tahifet (south of Algeria) has been recorded for the period from 1992 to 1997. These data have been used for the modelling and simulation of the PVPS system. The results indicated that the reliability and the accuracy of the simulated system are excellent and the correlation coefficient between measured values and those estimated by the ANFIS gave a good prediction accuracy of 98%. Additionally, test results show that the ANFIS performed better than the Artificial Neural Network (ANN), which has also being tried to model the system. In addition, a new configuration of an expert PVPS system is proposed in this work. The predicted electrical data by the ANFIS model can be used for several applications in PV systems.