batterydata/paper-abstracts huggingface dataset:
This paper investigates the overcharge-induced capacity fading behavior of large format lithium-ion batteries with Li y Ni1/3Co1/3Mn1/3O2 +Li y Mn2O4 composite cathode. The capacity degradation mechanism is studied using a prognostic/mechanistic model and incremental capacity analysis (ICA). The overcharge process can be divided into four stages. Loss of active material (LAM) in both the cathode and the anode and loss of lithium inventory (LLI) in different overcharge stages are quantified using the prognostic/mechanistic model. In Stage I, the battery shows no obvious capacity degradation until it is overcharged to 120% state of charge (SOC). In Stage II, LLI occurs as a result of lithium deposition, with LAM in the Li y Mn2O4 of the composite cathode. Internal resistance increases in Stage II indicating the thickening of the SEI film. In Stage III, LAM in both the cathode and the anode happen as the battery is overcharged to over 140% SOC. The battery starts to swell in this stage, as a result of the electrolyte oxidation. In Stage IV, the battery ruptures, with all the stored energy releasing instantly due to internal short circuit. Pinholes on the separator surface are observed after dissembling the batteries that are overcharged to 150% SOC or more.
The case of Katrina, a 25-year-old, married woman with a history of multiple psychiatric hospitalizations due to recurrent, impulsive suicide attempts, pervasive suicidal ideation, depression, and intrusive memories of sexual abuse, was presented to several experienced clinicians of various theoretical backgrounds. Regardless of the diagnostic label they assigned to the case or their theoretical orientation, the clinicians largely agreed on two levels of intervention: (a) the use of dialectical behavior therapy (DBT) and situational analysis in combination with other cognitive behavior therapies (CBTs) and interpersonal and behavioral interventions to address Katrina's current problems; and (b) interventions focused on Katrina's in-session behaviors and the use of the therapeutic relationship to provide Katrina with an opportunity to learn new, more adaptive coping skills in a safe and accepting environment. In this case conference, we invited several experienced clinicians—Nancy Caldwell, Kenneth Chase, Gerald Davison, Robert Kohlenberg, James McCullough, Shelley McMain, John Norcross, and Mavis Tsai—to share their wisdom and skill in applying their therapeutic approaches to the case of Katrina. Their response papers summarized Katrina's presenting problems; explicated their assessment plans; outlined case conceptualization; and suggested initial treatment plans. The information presented to the therapists was collected over 1 month, during four intake sessions at an outpatient clinic. Sources of information include intake interviews, her hospital records, testing report, and reports obtained from her couples therapist. The patient's name and identifying information have been changed to protect confidentiality.
Recent studies have shown that renewable energy resources will contribute substantially to future energy generation owing to the rapid depletion of fossil fuels. Wind and solar energy resources are major sources of renewable energy that have the ability to reduce the energy crisis and the greenhouse gases emitted by the conventional power plants. Reliability assessment is one of the key indicators to measure the impact of the renewable distributed generation (DG) units in the distribution networks and to minimize the cost that is associated with power outage. This paper presents a comprehensive reliability assessment of the distribution system that satisfies the consumer load requirements with the penetration of wind turbine generator (WTG), electric storage system (ESS) and photovoltaic (PV). A Markov model is proposed to access the stochastic characteristics of the major components of the renewable DG resources as well as their influence on the reliability of a conventional distribution system. The results obtained from the case studies have demonstrated the effectiveness of using WTG, ESS and PV to enhance the reliability of the conventional distribution system.
Universities are seen as a source of technology development that is useful to entrepreneurial activity. As a result, policy makers often consider mechanisms to stimulate technology commercialization at research universities as a way to encourage entrepreneurial activity in a region. However, the transfer of technology from universities to the private sector requires the exploitation of markets for knowledge, which are fraught with difficulty [Arrow, K., 1962. Economic welfare and the allocation of resources for inventions. In: Nelson, R. (Ed.), The Rate and Direction of Inventive Activity. Princeton, NJ: Princeton Univ. Press.]. This article examines the effect of one U.S. public policy initiative—the Bayh-Dole Act in the United States—on one aspect of technology commercialization—university patenting. Specifically, the article explores the university share of patents from 1969 through 1996 across 117 lines of business, and shows that the effectiveness of licensing in a line of business is significantly correlated with university share of patents in the post-Bayh-Dole period, but not in the pre-Bayh-Dole period. These results suggest that the Bayh-Dole Act provided incentives for universities to increase patenting in those fields in which licensing is an effective mechanism for acquiring new technical knowledge. The paper discusses the implications of this shift in patenting for research and public policy.
An Hybrid Renewable Energy Systems (HRES) can be described as a set of loads, renewable generation and storage units that can operate in standalone mode or connected to the main grid. In order to obtain a good compromise between capital investment and system reliability, an optimum sizing of all HRES components is needed. As power reliability, system cost and operation of the system depend on each other, the sizing methodology must be integrated with the energy management strategy (EMS). This paper presents an optimization methodology for sizing the components of a standalone hybrid wind/PV system (with hydrogen storage and battery storage), which integrates an EMS based on an economic model predictive control (EMPC) approach. The integrated problem to be solved is presented as a bi-level optimization framework composed of an outer loop and an inner loop. The outer loop is in charge of the HRES sizing and it is solved using Genetic Algorithms (GA). The inner loop solves the EMS for each candidate solution as a rolling horizon mixed integer linear problem (MILP). The results have shown an investment saving as well as a reduction of the operation costs with the proposed methodology.
In order to reverse the reactions of vanadium oxygen fuel cells and to regenerate vanadium redox flow battery electrolytes that have been oxidised by atmospheric oxygen, a vanadium proton exchange membrane water electrolyser was set up and investigated. Using an existing cell with a commercial and iridium-based catalyst coated membrane, it was possible to fully reduce V3.5+ and V3+ solutions to V2+ with the formation of oxygen and with coulomb efficiencies of over 96%. The cell achieved a maximum current density of 75 mA/cm2 during this process and was limited by the proximity of the V(III) reduction to the hydrogen evolution reaction. Due to the specific reaction mechanisms of V(IV) and V(III) ions, V(III) solutions were reduced with an energy efficiency of 61%, making this process nearly twice as energy efficient as the reduction of V(IV) to V(III). Polarisation curves and electrochemical impedance spectroscopy were used to further investigate the losses of half-cell reactions and to find ways of further increasing efficiency and performance levels.
Lithium lanthanum titanate oxide (LLTO)/polyacrylonitrile (PAN) submicron composite fiber-based membranes were prepared by electrospinning dispersions of LLTO ceramic particles in PAN solutions. These ionic-conducting LLTO/PAN composite fiber-based membranes can be directly used as lithium-ion battery separators due to their unique porous structure. Ionic conductivities were evaluated after soaking the electrospun LLTO/PAN composite fiber-based membranes in a liquid electrolyte, 1M lithium hexafluorophosphate (LiPF6) in ethylene carbonate (EC)/ethyl methyl carbonate (EMC) (1:1 vol). It was found that, among membranes with various LLTO contents, 15wt.% LLTO/PAN composite fiber-based membranes provided the highest ionic conductivity, 1.95×10−3 Scm−1. Compared with pure PAN fiber membranes, LLTO/PAN composite fiber-based membranes had greater liquid electrolyte uptake, higher electrochemical stability window, and lower interfacial resistance with lithium. In addition, lithium//1M LiPF6/EC/EMC//lithium iron phosphate cells containing LLTO/PAN composite fiber-based membranes as the separator exhibited high discharge specific capacity of 162mAhg−1 and good cycling performance at 0.2C rate at room temperature.
This study discusses the relationship between performance and carbon fiber diameter (400 nm–1 μm) in fuel cells employing carbon fiber paper produced from PAN fiber felt, and also examines the effect of carbon fiber paper thickness, air permeability, porosity, and surface resistivity on performance. The researchers fabricate gas diffusion layers (GDLs) with a small carbon fiber diameter from PAN fiber employing the two processes of stabilization and carbonization, and investigate the relationship between fiber diameter and air permeability in the gas diffusion layer material. Carbon fiber paper made in this study is left as is or impregnated with 10 wt% phenolic resin or FEP. When the tested area is 25 cm2, the test temperature 40 °C, and the carbon fiber paper impregnated with 10 wt% phenolic resin, the paper has a fiber diameter of 1 μm and an air permeability is 29 cm3 cm−2 s−1, and a test fuel cell yields 997 mA cm−2 at a load of 0.5 V. Carbon fiber paper impregnated with 10 wt% FEP has a smaller carbon fiber diameter of 400 nm and an air permeability of only 1 cm3 cm−2 s−1; a test fuel cell made with this material yields 683 mA cm−2 at a load of 0.5 V.
Amorphous poly(ethylene oxide) (PEO)–SiO2 composites are prepared by in situ reactions that involve the simultaneous formation of the polymer network and inorganic nanoparticles. The polymer matrix is formed by ultraviolet irradiation of a PEO macromer, and silica is produced in situ by the sol–gel method. The PEO–SiO2 composite mixed with LiBF4 is used as a lithium-ion conducting solid electrolyte and electrochemical transport properties such as ionic conductivity and Li+ transference number are measured. A significant increase in the Li+ transference number, up to 0.56, is found together with a slight decrease in the ionic conductivity. The results are interpreted in terms of interactions between the surface OH groups of the inorganic particles, the cations, the anions, and the ether oxygen atoms on the PEO backbone.
An optimal control strategy based on Pontryagin's Minimum Principle (PMP) is a promising solution because it provides a simple solution for controlling Hybrid Electric Vehicles (HEVs) and guarantees the best performance under reasonable conditions [1,2]. However, it needs to be very careful when applying the control strategy if inequality state constraints are active because handling the state constraints is one of the difficult issues in optimal control problems. In contrast to HEVs, Plug-in Hybrid Electric Vehicles (PHEVs) possibly consume all of the available electric energy, and so the activation of the state constraint on minimum State of Charge (SOC) is, unfortunately, a very common control problem for PHEVs. This paper describes mathematical derivations for an additional condition necessary for the inequality state constraints and solves the problem with several control options. Whereas PMP-based control allows a unique solution for HEVs [2], this paper shows that the control idea based on PMP produces a number of alternative solutions for PHEVs. However, battery efficiencies can be considered to evaluate the optimality of each solution, and simulation results from several control options show that maximizing a blended-mode control is the best solution to saving fuel for PHEVs. In terms of performance, the results of applying blended-mode control are very close to those obtained by applying a global optimal solution obtained from Dynamic Programming (DP).
Anticipation represents the tennis player's ability to forecast the future actions of its competitor. Tennis is, in general, an anticipation and space-time coordination sport. This study wishes to emphasize the importance of anticipation, in the efficiency of the tennis player's neuromuscular control, at a junior level. The study was conducted on 20 junior tennis players from the national lot. The measurement of the players was carried out in three steps: measuring the space-time anticipation with the Vienna Test Sport System testing battery, measuring the neuromuscular control, with the help of the condition simulator and measuring the balance with the aid of the Balance Platform.
The first record of Ornithodoros (Alectorobius) coniceps (Canestrini) was reported for Italy in 1877, inside the interstices of the ancient mosaics at S. Marco Basilica in Venice. Afterwards only few discoveries of the species are reported for Italy; the last record is dated back to 1984, in L’Aquila town (Abruzzo Region). The present study shows the data of a survey carried out as a result of a massive infestation by O. coniceps in an ancient villa in Anzio town (Latium region) recently restored. In the past decades the villa has been fallen into disrepair, becoming an occasional shelter for wild animals mainly pigeons, that colonized the whole building for generations. This case appears worthy of note because it is the first record of this species after more than 25 years in Italy. A total of 136 specimens were collected by three methods: manual, mechanical aspirators and Wilson traps. Wilson trapping indicates positive O. coniceps tropism for CO2.
Vehicle modeling can play an important role in vehicle power train design, control and energy management investigation. This paper presents a method for vehicle power train modeling. The key feature of the method is its presentation of the dynamic of vehicle based on the road information. This ability makes the method suitable for look-ahead energy management and fuel economy optimal control problems. With the aid of a road slope database, road geometry ahead of the vehicle is extracted. A fuzzy controller is developed that receives this information and controls the velocity of the vehicle with respect to its fuel consumption. In order to maintain the operation of the combustion engine near its efficient region, the fuzzy controller commands a continuously variable transmission. Simulations are carried out using real road data. The results are presented and discussed.
Silicon has been considered as one of the next generation high capacity anode materials. However, dissolution of cathode material in electrolyte, which is a general problem for lithium-ion batteries, hinders the industrial development of silicon anode. This paper designs electrochemical environment of Mn (II) dissolution to study the capacity fading of silicon anode. Electrochemical analysis and differential scanning calorimetry analysis reveals that Mn (II) will decrease the stability of solid electrolyte interphase, leading to acceleration of solid electrolyte interphase excessive growth and decreasing Columbic efficiency of anode.
Lithium-ion (Li-ion) batteries are of great interest to the automotive industry due to their higher power and energy density, higher cell voltage, longer cycle life and lower self-discharge compared to other battery chemistries. Electrochemical impedance spectroscopy is a powerful tool employed to investigate the fundamental electrochemical reactions within a Li-ion battery cell, which relates to state of charge, internal temperature and state of health. Its effectiveness has established it as a core method to study electrochemical behaviour of batteries in both off-line and on-line applications. In this work it is shown that in addition to state of charge, internal temperature and state of health, the time period between the removal of an electrical load and the impedance measurement affects the results. The study of five commercially available cells of varying capacities and electrode chemistries show that, regardless of cell type, maximum impedance change takes place within the first 4 h of the relaxation period. The root cause of this impedance change has been discussed from an electrochemical perspective.
Despite advances in traditional lithium-ion batteries in the past decades, its high cost has always been a bottleneck for large-scale applications. In this work, we demonstrate it is possible to replace expensive cathodes such as LiCoO2 with inexpensive stainless steel to store energy via a stripping/deposition mechanism: during charging, the stainless-steel cathode removes charges by releasing metal ions into the electrolyte, and during discharge, the metal ions re-deposit on the electrode reversibly. An anion exchange membrane allows passage of anions to balance the charge and prevents cross-over of cations. We show here a battery with a stainless-steel cathode and a lithium metal anode with a high discharge voltage of 2.5 V and good reversibility. We also study the mechanism at the stainless-steel electrode, as well as the kinetics of the battery system. Our work can potentially reduce the cost of energy storage by turning common construction materials into cathode materials. In addition, a metal cathode undergoing stripping/deposition gives a theoretical energy density comparable to lithium-sulfur batteries and provides a new exciting direction for future energy storage development.
The poly(3′,4′-ethylenedioxy-2,2′:5′,2″-terthiophene)/graphene nanoplatelet (poly(TET)/GNP) composites were synthesized by varying the ratio of GNP from 4wt% to 16wt% through mechanochemical method. The structure and morphology were characterized by the Raman spectroscopy, ultraviolet–visible (UV–vis) absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). The electrochemical performances of the composites were investigated by galvanostatic charge/discharge measurement, cycling stability, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results from Raman and UV–vis spectra showed that the composites were successfully synthesized, and the composites displayed a higher degree of conjugation than the pure poly(TET). The XRD and TEM results proved that the GNP existed in composites, and the ratio of GNP slightly affected the morphology of the poly(TET). The comparison results suggested that the composites showed a higher electrochemical activity than pure poly(TET). Moreover, all composites showed a lower internal resistance and better capacitive behavior than the poly(TET). Due to synergistic effects of GNP and poly(TET), the composite with 12wt% GNP has better electrochemical activity than others. And, the specific capacitance of the composite with 12wt% GNP reached to 206F/g, and had a capacitance retention rate of 78% over 1000 cycles.
Multi-walled carbon nanotubes synthesized using fluidized bed chemical vapor deposition technique were fluorinated sequentially to prepare a series of CF x battery electrodes. Primary battery performance was tested using CF x as a cathode against Li. Fully fluorinated MWNTs showed capacity exceeding 815 mAh g−1 while partially fluorinated samples showed systematically lowered capacity with decreasing x (in CF x ). However, fully fluorinated MWCNTs showed distinctly low rechargeable capacity compared to the subfluorinated samples when used as an anode against Li. Mildly fluorinated MWNTs show high capacity and better stability during charge–discharge cycles. High concentrations of fluorine seem to affect capacity retention due to the increased defect densities and reduced electronic conduction. These defects of nanotubes will provide additional pathways for lithium ions to diffuse within the core of the fluorinated structure and to access the electrochemically active C–F sites. XRD, XPS, and Raman spectroscopy were utilized to characterize the samples. Finally the electrochemical performance of fluorinated MWNTs was compared with that of Natural Chinese Graphite (NCG).
This paper addresses the problem of resource allocation to interdependent tasks in mobile ad hoc computational Grids. Dependencies between tasks imply that there can be heavy communication induced by data transfers between tasks executed on separate nodes. The communication in mobile ad hoc Grids is always expensive and unreliable, and therefore plays a critical role in application performance. There are several factors that contribute to communication cost. Unreliable and short-term connectivity can increase communication cost due to frequent failure and activation of links, and ineffective resource allocation can increase communication cost due to multi hop communication between dependent tasks. To reduce communication cost, an effective and robust resource allocation scheme is required. However, the design of such a scheme for mobile ad hoc computational Grids exhibits numerous difficulties due to the constrained communication environment, node mobility, and lack of pre-existing network infrastructure. In this paper, we propose a two-phase resource allocation scheme to reduce communication cost between dependent tasks. The scheme is divided into two phases. The first phase exploits the history of user mobility patterns to select nodes that provide long-term connectivity and the second phase takes into account the task and dependency types, and uses the distance information among the nodes selected in the first phase to reduce communication costs. The scheme is validated in a simulation environment using various workloads and parameters.
The feasibility of the Pechini method for the preparation of LiNi1/3Mn1/3Co1/3O2 with characteristics appropriate for Li-ion battery positive electrodes was investigated. The method involves formation of one single chemically homogenous precursor material and thus permits reduced calcination times and minimal lithium evaporation. The physical and electrochemical properties of the materials were investigated with variation in final calcination temperature. Chemical analysis showed that the materials could be prepared with high crystallinity and yet little or no loss of lithium. The material calcined at 1000°C showed the highest specific capacity—180mAhg−1 when cycled between 4.5 and 3V, and it maintained its capacity over 50 cycles. The advantage of this material over those prepared at 800 and 900°C can probably be attributed to the fact that the degree of crystallinity, crystallite size and size of the primary particles increase with calcination temperature, and that the powder attains a more suitable morphology which promotes electronic connectivity to all of the oxide material. A temperature above 1000°C should however not be used as indicated by an abrupt change in lattice parameters and decrease in electronic conductivity when going from 1000 to 1050°C. The Pechini method presents an attractive option for the preparation of LiNi1/3Mn1/3Co1/3O2 positive electrode material.