batterydata/paper-abstracts huggingface dataset:
Energy is the lifeblood of the modern world. Because of the negative environmental impacts and limited sources of fossil fuels, researchers are increasingly focusing on renewable energy sources, particularly solar energy due to its cleanliness and natural availability. Along with photovoltaic systems, solar thermal energy has been used over the last few decades to meet the refrigeration needs for both domestic and industrial purposes. This study presents a review of different solar thermal refrigeration systems, with a specific focus on solar absorption refrigeration systems and solar adsorption refrigeration systems within various working fluids. The different working pairs are illustrated by considering their coefficients of performance, specific cooling power, cooling capacity and minimum and maximum working temperatures. By considering cooling efficiency and other problems, such as swelling and agglomeration, the study also explores solar thermal hybrid cooling systems with heterogeneous composite pairs.
The global energy sector is expected to experience a gradual shift towards renewable energy sources in the coming decades. Climate change as well as energy security issues are the driving factors. In this process electricity is expected to gain importance to the cost of fuels. However, these new technologies are in many cases dependent on various metals. This analysis evaluates the need for special metals and compares it with known resources in order to find possible bottlenecks in the market. The time perspective of the analysis reaches to the year 2050. Following technologies have been selected for evaluation: solar electricity, wind power, fuel cells, batteries, electrolysis, hydrogen storages, electric cars and energy efficient lighting. The metals investigated belong either to the semiconductors, platinum group metals, rare earth metals or are other critical metals like silver and cobalt. The global transition of the energy sector is modelled with TIMES. According to the results the most critical market situation will be found in silver. Other elements, for which bottlenecks in the market seem possible, include tellurium, indium, dysprosium, lanthanum, cobalt, platinum and ruthenium. Renewable energy scenarios presented by the IPCC Fifth Assessment Report seem partly unrealistic from the perspective of critical metals.
Todorokite-type MnO2-doped with Co and Fe has been synthesized by hydrothermal treatment of layered metal-doped manganese oxide, buserite, in water at 120–200°C. The prepared todorokite products have been characterized by XRD and energy dispersive X-ray spectroscopic (EDX) measurements, TEM observation and thermogravimetric analysis. These measurements showed that the hydrothermal products are the metal-doped todorokite phase having large (3×3) tunnel structure, and the chemical compositions are shown to be Mg x M y Mn1−y O2·zH2O, where x =0.08–0.10, y =0.23–0.29, z =0.35–0.54 in M=Co and x =0.13–0.14, y =0.03–0.16, z =0.19–0.28 in M=Fe. The preliminary electrochemical characteristics including charge–discharge cyclings of the metal-doped-todorokite electrodes were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries. The metal-doped todorokite exhibited S-shaped discharge behavior and the Co-doped one with x =0.10, y =0.29 showed a high discharge capacity of ca. 132mAhg−1-oxide and cycling capacity of 90–100mAhg−1.
Face recognition systems based on Convolutional Neural Networks (CNNs) or convolutional architectures currently represent the state of the art, achieving an accuracy comparable to that of humans. Nonetheless, there are two issues that might hinder their adoption on distributed battery-operated devices (e.g., visual sensor nodes, smartphones, and wearable devices). First, convolutional architectures are usually computationally demanding, especially when the depth of the network is increased to maximize accuracy. Second, transmitting the output features produced by a CNN might require a bitrate higher than the one needed for coding the input image. Therefore, in this paper we address the problem of optimizing the energy-rate-accuracy characteristics of a convolutional architecture for face recognition. We carefully profile a CNN implementation on a Raspberry Pi device and optimize the structure of the neural network, achieving a 17-fold speedup without significantly affecting recognition accuracy. Moreover, we propose a coding architecture custom-tailored to features extracted by such model.
Sometimes the normal course of events is disrupted by a particularly swift and profound change. Historians have often referred to such changes as “revolutions”, and, though they have identified many of them, they have rarely supported their claims with statistical evidence. Here, we present a method to identify revolutions based on a measure of multivariate rate of change called Foote novelty. We define revolutions as those periods of time when the value of this measure is, by a non-parametric test, shown to significantly exceed the background rate. Our method also identifies conservative periods when the rate of change is unusually low. We apply it to several quantitative data sets that capture long-term political, social and cultural changes and, in some of them, identify revolutions — both well known and not. Our method is general and can be applied to any phenomenon captured by multivariate time series data of sufficient quality.
Although hydrocephalus affects approximately 80% of children with a posterior fossa tumor, its impact on neurodevelopmental outcomes remains unclear. We investigated the effects of hydrocephalus severity on the development of cognitive, motor, academic, and attention skills in 15 children with cerebellar injury after treatment for a tumor sustained during preschool years. Significant impairment was indicated by scores 2 S.D.s or more below the test norm mean. Results indicated substantial intra-individual and interindividual variation, with little consistent influence of hydrocephalus severity on outcomes. Generally, children with moderate hydrocephalus were least impaired, but the child without hydrocephalus performed most poorly. Those who received a shunt generally performed higher on many of the cognitive, but not motor, tests. Thus, when considering differences within and across individuals, neither hydrocephalus severity nor shunt placement alone is a strong predictor of neurodevelopmental outcomes.
The xLi2MnO3·(1−x)Li(Mn0.33Co0.33Ni0.33)O2 (x = 0.3, 0.5, 0.7) cathode material with uniform spherical morphology has been successfully prepared by a facile carbonate co-precipitation method. These cathode materials are characterized by X-ray powder diffractometry (XRD), scanning electron microscopy (SEM), and inductively coupled plasma emission spectrometry (ICP-AES). The electrochemical properties of these cathode materials have been studied by charge/discharge cycling at various current rates. The results of these studies suggest that among these materials, the composite cathode with x = 0.5 (Li1.2Mn0.54Co0.13Ni0.13O2) exhibiting the better electrochemistry performances than those with x = 0.3 and 0.7. Correspondingly, 2 wt% CuO-coated Li1.2Mn0.54Co0.13Ni0.13O2 possess better cycling stability (173.9 mAh g−1 after 50 cycles at 1C rate and 50 cycles at 2C rate) and rate capability than the pristine one. Meanwhile, the CuO-coating layer of the material has a contribution to improve its thermal stability. We believe it is a promising cathode for the high energy lithium batteries.
Organized structures have shown significant improvements in the electrochemical performance of rechargeable batteries. In this research, we investigated three-dimensionally connected open-porous aluminum alloy (AlSi12) as substrate coated with SiO2 nanoparticles as potential electrode in a Li-ion battery. Effects and morphological characteristics of such structure were investigated through electrochemical experiments. Results showed that the electrode performance was influenced by the pore size of the substrate. When the electrode pore size was decreased from 3000 to 2000 µm, there was a decrease of 140% in the electrode-specific capacity. Comparing with the reference sample that has no pores, the specific capacity can be increased by at least a factor of two when pores are introduced. This is due to the transition from the non-Faradic current in the non-porous non-coated electrode to the Faradic current in the porous coated electrode. This finding opens the potential for future study in kinetics of electrochemical reactions in open-pored hierarchical structures.
Monodisperse Li4Ti5O12 (LTO) microspheres with different primary crystallite sizes were synthesized using the same cetyltrimethylammonium bromide-assisted hydrothermal method but different post-calcination temperatures (600 and 700°C). The two different LTO microspheres have the same diameter about 4μm, but smaller primary crystallite size and higher surface area are obtained at 600°C (LTO600). The specific capacities at 0.1C are both close to the theoretical capacity of LTO for the two samples; higher specific capacity is obtained with LTO600 at high C-rate, indicating beneficial effect of smaller primary crystallite size and larger surface area. Notably, LTO600 exhibits superior rate performance and excellent cyclic stability. The charge specific capacities at 5C, 10C, 20C and 50C are up to 158, 154, 153 and 148mAhg−1, respectively. More importantly, the capacity retention after 400 cycles at 5C is as high as 150mAhg−1.
This study aimed to determine the neurodevelopmental (ND) outcome for children with hypoplastic left heart syndrome (HLHS) at early school age. English-speaking patients who underwent the Norwood procedure between 2000 and 2005 were eligible at 4–6 years of age for ND testing. Of the 72 eligible patients, 44 (61 %) agreed to participate, and 37 completed ND testing before the close of the study. Three subjects were excluded from analyses due to late stroke. The ND testing included intelligence, visual motor integration, memory and motor and language skills. Parents and teachers completed measures of behavior and attention problems. Subjects’ scores and parent/teacher ratings were converted to z-scores and compared with test norms. Higher scores on child measures represent better outcomes, whereas higher scores on parent and teacher rating scales indicate more problems. The average ND performance of the tested cohort fell within one standard deviation of the test norms for all measures. However, the subjects performed significantly lower than the test norms on measures of visual-motor integration, fine motor skills, memory, and word structure (z = −0.42 to −0.54; p < 0.005). On the parent and teacher completed measures, the subjects scored higher than the test norms on attention problems (z = 0.40–0.62; p < 0.005). Although the overall ND performance of the cohort was normal, the subjects showed relative weakness in visual motor and attention skills. Ongoing developmental monitoring of these children is recommended to guide interventions that may improve individual outcomes and to assess the impact of changes in clinical management strategies on functional outcomes.
LiNi0.5Mn1.5O4 (LNMO) composite electrodes having the same formulation as to percentage of active material mass, binder and carbons, including reduced graphene oxide, were characterized in EC: DMC – 1M LiPF6 by cyclic voltammetry, charge/discharge cycles and impedance spectroscopy. The results demonstrate the beneficial effect on the electrode cycling stability in increasing C-rate to 1C, in limiting the charge voltage at 4.8 V and in covering the LNMO by partially reduced graphene oxide. The paper also discusses the evaluation of lithium diffusion coefficient in LNMO from cyclic voltammetry data in regard to the discrepancies reported in literature on this matter.
Lithium-sulfur (Li-S) batteries suffer from the dissolution of its intermediate charge products (polysulfides) in organic electrolytes, which limits the utilization, rate performance and cycling stability of S cathode materials. Formation of protective surface coatings on S cathodes may effectively overcome such a challenge. Here, we explored a simple, low cost, and widely applicable method that offers in-situ formation of a protective coating on the S-based cathode by using lithium bromide (LiBr) as a novel electrolyte additive. Quantum chemical (QC) studies suggested that pre-cycling a S cathode at high potentials is needed to oxidize the Br- and induce formation of DME(-H) radicals, which are involved in the formation of a polymerized protective layer of a solid electrolyte interphase (SEI) on a S cathode at high potentials. Experimental studies with a LiBr additive confirmed that 3 pre-cycles in a voltage range of 2.5–3.6V are sufficient to achieve the formation of a robust Li ion permeable SEI on the cathode, effectively preventing the dissolution of polysulfides into electrolyte. As a result, almost no degradation was observed within 200 cycles, compared to more than 40% of capacity loss in the benchmark control cells without LiBr or the pre-cycles. Post-mortem analysis on both the cathode and anode sides of the LiBr-comprising cells further provided evidence for the in-situ SEI formation on the cathode and the lack of polysulfides’ re-precipitation. In addition, such studies showed smooth surface on the cycled Li metal anode, in contrast to the rough Li SEI with dendrites and polysulfides in the benchmark cells.
This paper proposes a convex non-linear cost saving model for optimal economic dispatch in a microgrid. The model incorporates energy storage degradation cost and intermittent renewable generation. Cell degradation cost being a non-linear model, its incorporation in an objective function alters the convexity of the optimization problem and stochastic algorithms are required for its solution. This paper builds on the scope for usage of macroscopically semi-empirical models for degradation cost in economic dispatch problems and proves that these cost models derived from the existing semi-empirical capacity fade equations for LiFePO4 cells are convex under some operating conditions. The proposed non-linear model was tested on two data sets of varying size which portray different trends of seasonality. The results show that the model reflects the trends of seasonality existing in the data sets and it minimizes the total fuel cost globally when compared to conventional systems of economic dispatch. The results thus indicate that the model achieves a more accurate estimate of fuel cost in the system and can be effectively utilized for cost analysis in power system applications.
NiOOH nanosheet/graphene hydrogels (H–NiOOH/GS), with mesoporous NiOOH nanosheets uniformly dispersed within the highly interconnected 3D graphene network, are constructed and studied for the first time by a mixed solvothermal and hydrothermal reaction. The effect of solvent composition on the morphology, phase, dispersibility of nanocrystal and hydrogel strength is systematically studied. As binder-free electrodes of supercapacitors, H–NiOOH/GS delivers high capacitance of 1162Fg−1 at 1Ag−1 with excellent rate capability (981Fg−1 at 20Ag−1). The charge-storage mechanisms of H–NiOOH/GS are in-depth investigated by quantifying the kinetics of charge storage, which reveals that NiOOH exhibits both capacitive effects and diffusion-controlled battery-type behavior during charge storage. Additionally, solvothermal-induced pure graphene hydrogels (H-GS) are also prepared and used as the negative electrode for the first time, which show an impressive specific capacitance of 425 and 368Fg−1 at 5 and 40mVs−1, respectively. Benefitting from the synergistic contribution of both positive and negative electrodes, the assembled H–NiOOH/GS//H-GS asymmetric supercapacitors achieve a remarkable energy density of 66.8Whkg−1 at a power density of 800Wkg−1, and excellent cycling stability with 85.3% capacitance retention after 8000 cycles, holding great promise for energy storage applications.
An electroless nickel process was used for the preparation of a thin-film current collector for concentric three-dimensional lithium and lithium-ion microbatteries. Ni–P coatings were deposited autocatalytically with the use of nickel sulfamate or nickel sulfate as a source of Ni2+ and sodium hypophosphite as a reducing agent. The synergistic effect of sodium acetate and citric acid was found to provide marked improvement in the pH stability of the sulfamate electrolyte. This enabled deposition of a conformal, fine-grained film on the high-aspect-ratio glass capillary and perforated-silicon substrates.
Nano-SiO2 as dopant was used for preparing polyethylene-supported poly(methyl methacrylate-co-butyl acrylate) (P(MMA-co-BA)/PE) based membrane and corresponding gel polymer electrolyte (GPE), which is applied to improve the cyclic stability of high voltage lithium ion battery. P(MMA-co-BA)/nano-SiO2/PE based membranes and corresponding GPEs were characterized with scanning electron spectroscopy, X-ray diffraction, electrochemical impedance spectroscopy, mechanical test, thermogravimetric analysis, linear sweep voltammetry, and charge/discharge test. It is found that the GPE with 5wt.% nano-SiO2 shows the best performance. Compared to the undoped membrane, the 5wt.% nano-SiO2 doped membrane has a better pore structure and higher electrolyte uptake, leading to the enhancement in ionic conductivity of the resulting GPE from 1.23×10−3 to 2.26×10−3 S.cm−1 at room temperature. Furthermore, the thermal stability of the doped membrane is increased from 300 to 320°C while its decomposition potential of GPE is from 5.0 to 5.6V (vs. Li/Li+). The cyclic stability of Li/GPE/Li(Li0.13Ni0.30Mn0.57)O2 cell at the high voltage range of 3.5V ∼ 5.0V is consequently improved, the capacity retention of the cell using the doped membrane is 92.8% after 50 cycles while only 88.9% for the cell using undoped membrane and 66.9% for the cell using liquid electrolyte.
The reverse logistic challenge of transporting waste automotive lithium ion battery (LIB) packs is an escalating concern as the world-wide sale of electric vehicles (EVs) continues to rise. Under the European Union (EU) Battery Directive, EV manufacturers are classified as battery producers and are responsible for the collection, treatment and recycling of waste or damaged vehicle batteries. The European agreement concerning the International Carriage of Dangerous Goods by Road (ADR) stipulates that damaged or defective LIB packs must be transported in approved explosion proof steel containers. This necessitates costly testing in order to meet ADR requirements. Furthermore, the extra size and weight of this packaging adds further prohibitive expense to the transportation of damaged or defective LIB. In this study, cryogenically frozen cells are shown to be unable to release any energy even in extreme abuse conditions. This is demonstrated on two different cell chemistries and form factors. Experiments have shown that the possibility of thermal runaway is completely removed and therefore it is argued that LIBs may be transported safely whilst cryogenically frozen. Moreover, flash freezing is shown to have little effect on the electrical performance (energy capacity and impedance) even after five repetitive cryogenic cycles. Thus, facilitating the potential reuse and remanufacture of individual LIB cells from a complete damaged pack, prolonging the useful life, reducing the consumption of raw materials, and improving environmental sustainability of EV introduction.
The voltammetry of microparticles and scanning electrochemical microscopy methodologies are applied to characterize praseodymium centers in praseodymia-doped zircon (Pr x Zr(1−y)Si(1−z)O4; y + z = x; 0.02< x <0.10) specimens prepared via sol–gel synthetic routes. In contact with aqueous electrolytes, two overlapping Pr-centered cathodic processes, attributable to the Pr (IV) to Pr (III) reduction of Pr centers in different sites are obtained. In water-containing, air-saturated acetone and DMSO solutions as solvent, Pr x Zr(1−y)Si(1−z)O4 materials produce a significant catalytic effect on the electrochemical reduction of peroxide radical anion electrochemically generated. These electrochemical features denote that most of the Pr centers are originally in its 4+ oxidation state in the parent Pr x Zr(1−y)Si(1−z)O4 specimens. The variation of the catalytic performance of such specimens with potential scan rate, water concentration and Pr loading suggests that Pr is not uniformly distributed within the zircon grains, being concentrated in the outer region of such grains.
Facing severe environmental problems, to improve the efficiency of the hydraulic construction machinery is in great demand. The potential energy when the boom is lowering is dissipated as heat in hydraulic system. It is urgent to improve the maximum use of regeneration energy to reduce the fuel consumption. This paper first analyzes the proportion of regeneration energy for each actuator and studies the special working style of the boom energy regeneration system (ERS) in a 20-t HE. Then, types of the ERS are discussed. The research and development of the electric ERS technology and the hydraulic ERS technology based on construction machinery are reviewed. At last, the paper puts forwards the challenges and the future development of ERSs.
This paper describes the statistical analysis of recorded data parameters of electrical battery ageing during electric vehicle use. These data permit traditional battery ageing investigation based on the evolution of the capacity fade and resistance raise. The measured variables are examined in order to explain the correlation between battery ageing and operating conditions during experiments. Such study enables us to identify the main ageing factors. Then, detailed statistical dependency explorations present the responsible factors on battery ageing phenomena. Predictive battery ageing models are built from this approach. Thereby results demonstrate and quantify a relationship between variables and battery ageing global observations, and also allow accurate battery ageing diagnosis through predictive models.
This paper presents an investigation on the unbalanced discharging and aging due to temperature difference between the parallel-connected cells. A thermal–electrochemical model is developed for the parallel-connected battery pack. The effects of temperature difference on the unbalanced discharging performances are studied by simulations and experiments. For the parallel-connected cells, the cell at higher temperature experiences a larger current in the early discharging process before approximately 75% of depth of discharge (DOD). When the discharge process approaches the voltage turn point of the battery pack, the discharge current through the cell at higher temperature begins to decrease significantly. After the DOD reaches approximately 90%, the discharge current of the cell at higher temperature rises again. Correspondingly, the changes in the discharging current through the cell at lower temperature are opposite to that of the cell at higher temperature. Simulations also show that the temperature difference between the parallel-connected cells greatly aggravates the imbalance discharge phenomenon between the cells, which accelerates the losses of the battery pack capacity. For the parallel-connected battery pack, the capacity loss rate approximately increases linearly as the temperature difference between the cells increases. This trend is magnified with the increase of operating temperature.