batterydata/paper-abstracts huggingface dataset:
Battery state of charge (SOC) estimation is a crucial function of battery management systems (BMSs), since accurate estimated SOC is critical to ensure the safety and reliability of electric vehicles. A widely used technique for SOC estimation is based on online inference of battery open circuit voltage (OCV). Low-current OCV and incremental OCV tests are two common methods to observe the OCV-SOC relationship, which is an important element of the SOC estimation technique. In this paper, two OCV tests are run at three different temperatures and based on which, two SOC estimators are compared and evaluated in terms of tracking accuracy, convergence time, and robustness for online estimating battery SOC. The temperature dependency of the OCV-SOC relationship is investigated and its influence on SOC estimation results is discussed. In addition, four dynamic tests are presented, one for estimator parameter identification and the other three for estimator performance evaluation. The comparison results show that estimator 2 (based on the incremental OCV test) has higher tracking accuracy and is more robust against varied loading conditions and different initial values of SOC than estimator 1 (based on the low-current OCV test) with regard to ambient temperature. Therefore, the incremental OCV test is recommended for predetermining the OCV-SOCs for battery SOC online estimation in BMSs.
Thermal energy storage promises to be cheaper, with significantly lesser environmental encroachment, compared to electrical energy storage in batteries. Among all thermal energy storage systems, thermochemical energy storage is the most promising due to its high energy density, high exergetic efficiency, and high operating temperature. This paper presents a review of thermal energy storage systems that are suitable for concentrating solar thermal power plant. The review here mainly focuses on experimental studies carried out on solid-gas, gas-gas, and sulfuric acid/sulfur-based thermochemical energy storage systems that operate above 300 °C. Also, various reactor designs and storage concepts for solid-gas and gas-gas reaction systems and cyclic studies for the case of a solid-gas system are addressed. Finally, a comparative summary is presented, preparing the path for the future course of research and development. The review reveals that the carbonate systems are an economically viable option as future thermal energy storage system if their cyclic stability and reversibility are improved. A new metal hydride thermal energy storage system is proposed that would provide cooling and heat upgradation as an additional output. For gas-gas reactions, the major challenges are the development of efficient solar receiver and optimization of the catalyst use.
This work describes a new Prussian blue (PB)-based electrochemical sensor based on chitosan (CS)-functionalized graphene nanosheets which exhibit good dispersibility and stability in aqueous solution. The morphology and composition of the graphene-CS/PB nanocomposite sheets were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The electrochemical behavior of the resulting sensor was investigated using cyclic voltammetry and amperometry. The modified sensor showed good electrocatalytic activity in the reduction of hydrogen peroxide and was used as an amperometric sensor. The sensor exhibited a linear response for H2O2 over concentrations ranging from 0.01 to 0.4mM with a high sensitivity of 816.4μA/(mMcm2) and a low detection limit (S/N=3) of 0.213μM. These parameters compare favorably with other PB-based electrodes. Furthermore, the new sensor exhibited freedom from interference from other co-existing electroactive species in human blood. This work describes a new type of graphene nanocomposite-modified electrode for amperometric biosensors.
Background Gallbladder cancer (GC) is considered a relatively rare malignancy with extensively poor prognosis. To guide clinicians in selecting treatment options for GC patients, reliable markers predictive of poor clinical outcome are desirable. This study analyzed the correlation of NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and multidrug resistance-related protein 3 (MRP3) in GC and their relationships to clinicopathologic features and survival. Material and Methods We immunohistochemically investigated 59 specimens of gallbladder adenocarcinoma tissues using Nrf2, HO-1, and MRP3 antibodies. Results There were significant correlations between the high level of Nrf2, HO-1, and MRP3 expression and the tumor differentiation, Nevin staging, and metastasis. Significant positive correlations were found between the expression status of Nrf2 and that of HO-1 and MRP3 (r = 0.38, P = 0.008 and r = 0.59, P < 0.001, respectively). High Nrf2 expression was significantly associated with shorter overall survival times in univariate analysis (log-rank test, P < 0.001), being also identified as an independent prognostic factor in multivariate analysis (P = 0.035). Conclusions Nrf2, HO-1, and MRP3 were associated with certain clinicopathologic parameters in GC. Evaluation of Nrf2 expression may be an important factor in identifying a poor prognostic group of GC.
Aims This study investigated autonomic nervous system function in subjects with diabetes during exercise and recovery. Methods Eighteen type 2 diabetics (age 55±2years) and twenty healthy controls (age 51±1years) underwent two 16-min bicycle submaximal ECG stress tests followed by 45min of recovery. During session #2, atropine (0.04mg/kg) was administered at peak exercise, and the final two minutes of exercise and entire recovery occurred under parasympathetic blockade. Plasma catecholamines were measured throughout. Parasympathetic effect was defined as the difference between a measured parameter at baseline and after parasympathetic blockade. Results The parasympathetic effect on the RR interval was blunted (P =.004) in diabetic subjects during recovery. Parasympathetic effect on QT–RR slope during early recovery was diminished in the diabetes group (diabetes 0.13±0.02, control 0.21±0.02, P =.03). Subjects with diabetes had a lower heart rate recovery at 1min (diabetes 18.5±1.9bpm, control 27.6±1.5bpm, P <.001). Conclusions In subjects with well-controlled type 2 diabetes, even with minimal evidence of CAN using current methodology, altered cardiac autonomic balance is present and can be detected through an exercise-based assessment for CAN. The early post-exercise recovery period in diabetes was characterized by enhanced sympathoexcitation, diminished parasympathetic reactivation and delay in heart rate recovery.
A series of RuO2 modified LiNi0.5Mn1.5O4 materials are successfully prepared by the precipitation method. X-ray photoelectron spectroscopy confirms the presence of Ru4+ in the materials. Scanning electron microscope and high resolution transmission electron microscope show that RuO2 covers the surface of LiNi0.5Mn1.5O4 particles. The amounts of RuO2 in the materials are determined to be 1.6wt.%, 2.0wt.% and 3.0wt.%, respectively. The electrochemical kinetics of the materials is studied by cyclic voltammetry and electrochemical impedance spectroscopy. The results show that RuO2 modification decreases the polarization of the electrode, prevents the side reactions of the electrode and the electrolyte, and improves the charge transfer reactions at the electrode interface, all of which are beneficial for the electrochemical properties of LiNi0.5Mn1.5O4. In all samples tested, the one containing 2.0wt.% of RuO2 exhibits superior electrochemical performance. It shows discharge capacities of 131.7mAhg−1 (room temperature) and 129.7mAhg−1 (60°C) at the 0.5C rate with the corresponding capacity retention of 97.7% and 97.2% after 100 cycles. In addition, the material delivers high discharge capacities of 104.5mAhg−1at the 5C rate and 66.1mAhg−1 at the 10C rate, demonstrating its excellent rate capability.
In this study the effects of 3,4-dichloroaniline (3,4-DCA), a decomposition product of the herbicides propanil and diuron (and other pesticides), and diazinon, a neurotoxic insecticide, on early life stages of zebrafish Danio rerio were assessed. The toxicity of these substances with different modes of action (acetylcholine esterase inhibitor vs. polar narcosis) was tested for single substances as well as in binary mixtures. To study effects on different biological organisation levels (from the molecular up to the whole organism level) the molecular stress response regarding Hsp70, the embryonic and larval development and the locomotor activity were investigated as integrative biomarkers. In single substance tests 3,4-dichloroaniline elicited deformations at ≥0.25 mg/l during the 11 days subchronic test, whereas locomotor activity and mortality were impaired at ≥0.5 mg/l. Diazinon effects on those parameters were obvious at ≥2 mg/l, except for the deformation rate (11 days:1 mg/l). In equitoxic mixtures of both substances concentration additivity was observed for deformation rate and mortality (11 days). An increase in the Hsp70 content occurred in zebrafish exposed to 0.25 mg 3,4-DCA/l as well as to 0.05 mg diazinon/l; in mixtures concentration additivity could be shown. The investigated endpoints varied in respect to their sensitivity, with deformations and Hsp70 levels as most sensitive parameters concerning 3,4-DCA and Hsp70 as most sensitive parameter concerning diazinon. Accordingly, for an integrated understanding of the effects of chemicals and their mixtures on fish, a battery of different test methods should be applied.
Purpose To evaluate changes in ocular wavefront aberrations and retinal image quality with objective accommodation in normal human eyes. Setting Department of Ophthalmology and Visual Science, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea. Design Cohort study. Methods Healthy emmetropic eyes were measured with an iTrace wavefront aberrometer while the subjects fixated at far (6.0 m) and near (40 cm). Wavefront data were analyzed with 3.0 mm and 5.0 mm pupil diameters. The influence of higher-order aberrations (HOAs) on retinal image quality was simulated by computing the modulation transfer function (MTF) from the wavefront aberrations. Results Eighty-two eyes of 42 subjects were evaluated. The root mean square values of total HOAs before and after accommodation with 5.0 mm pupils were statistically significantly different (P=.021). In particular, total spherical aberrations became more negative with accommodation, and the difference was statistically significant with 3.0 mm and 5.0 mm pupils (both P<.001). The MTF curves were significantly different before and after accommodation at 5 cycles per degree (cpd) and 10 cpd with 5.0 mm pupils (P=.031 and P=.045, respectively). Conclusions Ocular wavefront aberrations and retinal image quality changed with accommodation in normal human eyes. Total spherical aberration changed more than other HOAs with accommodation. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.
ABSTRACT From energy and environmental consideration, an industrial waste product, coal tar pitch (CTP), is used as the carbon source for Si/AC composite. We exploited a facile sintering method to largely scale up Si/amorphous carbon nanocomposite. The composites with 20wt.% silicon with PVdF binder exhibited stable lithium storage ability for prolonged cycling. The composite anode delivered a capacity of 400.3mAhg−1 with a high capacity retention of 71.3% after 1000 cycles. Various methods are used to investigate the reason for the outstanding cyclability. The results indicate that the silicon nanoparticles are wrapped by amorphous SiO x and AC in Si/AC composite. This uniform structure is very favorable to lithium storage, the SiO x and AC layers can supply sufficient conductivity and strong elasticity to suppress the stress resulting from the reaction of Si with Li during charge/discharge process.
Amorphous Mg65Ni27La8 alloy is prepared by melt-spinning. The alloy surface is modified using different contents of graphite to improve the performances of the Mg65Ni27La8 electrodes. In detail, the electrochemical properties of (Mg65Ni27La8)+ xC (x =0–0.4) electrodes are studied systematically, where x is the mass ratio of graphite to alloy. Experimental results reveal that the discharge capacity, cycle life, discharge potential characteristics and electrochemical kinetics of the electrodes are all improved. The surface modification enhances the electrocatalytic activity of the alloy, reduces the contact resistance of the electrodes and obstructs the formation of Mg(OH)2 on the alloy surface. An optimal content of graphite has been obtained. The (Mg65Ni27La8)+0.25C electrode has the largest discharge capacity of 827mAhg−1, which is 1.47 times as large as that of the electrode without graphite, and the best electrochemical kinetics. Further increasing of graphite content will lead to the increase of contact resistance and activation energy for charge-transfer reaction of the electrode, resulting in the degradation of electrode performance.
Lithium-ion (Li-ion) batteries have been implemented for numerous applications, one of which is in plug-in hybrid electric vehicles (PHEV) and pure electric vehicles (EV). In an effort to prolong battery life it is important to understand the mechanisms that cause reduced battery capacity with aging. In this work, nanomechanical characterization and mechanical integrity studies were carried out on unaged and aged LiFePO4 battery cathodes using atomic force microscopy (AFM) and nanoindentation. Changes in hardness, elastic modulus, creep, nanowear, nanoscratch and nanofriction properties were measured. Measured changes are believed to occur as a result of coarsening and agglomeration of LiFePO4 nanoparticles.
Over the last twenty years, there has been a resurgent research interest in direct borohydride fuel cells (DBFCs) highlighting the fundamental aspects that need to be addressed to achieve their optimal performance. The main problem is the hydrolysis of borohydride ions, which generates hydrogen, decreases the energy efficiency and reduces the power density. The electrons released during borohydride oxidation, the cell potential difference and the power output are strongly influenced by the choice of anode and cathode, including three-dimensional and nanostructured electrodes, the electrolyte composition and the operating conditions. Extensive investigations on various anodic electrocatalysts and their effect on the oxidation and hydrolysis have been quantified as well as the cathode catalyst and its influence on the overall fuel cell performance. Computational methods such as ab-initio and physical modelling could play prominent roles in the design and fundamental characterisation of DBFCs but are currently underused and only small number of studies in well-defined materials such as Pt (111) or Au (111) exist. Cell design and configuration have also been considered but the basic requirement to engineer a selective catalyst able to suppress the hydrogen evolution and the elucidation of the mechanism of borohydride ion oxidation, remain.
The possibility of interfacial storage at low potential for electrode materials reacting through conversion reactions was evaluated. The amount of charge that could be stored through the proposed interfacial mechanism was estimated for a range of different materials and found to be much lower than those observed experimentally. Moreover, the slope of the potential decay and the influence of the current in the extent of stored capacity for experiments carried out in composite electrodes containing Co3O4 are not consistent with a capacitive-like mechanism. In summary, no evidence for capacitive storage could be found, our results being in agreement with the process taking place at low potential being solely related to electrolyte decomposition.
Two proof-of-concept batteries were designed and prepared for X-ray microtomography and radiography characterizations to investigate the degradation mechanisms of silicon (Si) based half cells during the first cycle. It is highlighted here for the first time that, apart from the significant volume expansion-induced pulverization, the electrochemical “deactivation” mechanism contributes significantly to the capacity loss during the first charge process. In addition, the unexpected electrochemically inactive Si particles are also believed to substantially decrease the energy density due to the inefficient utilization of loaded active material. These unexpected findings, which cannot be deduced from macroscopic electrochemical characterizations, expand the inherent explanations for performance deterioration of Si-anode material based lithium ion batteries (LIBs) and emphasize the vital value of microscopic techniques in revealing the correlation between macroscopic electrode structure and the overall electrochemical performance.
In this study we evaluate the influence of tobacco smoke on the physico-chemical characteristics of PM10 in different environments: outdoors, a smoking room, the same room after a 7-day absence of smokers and in a smoke-free office. The latter office was close to the smoking room, separated by a corridor. The coarse (PM10−2.1) and fine (PM2.1) fractions of PM10 collected in the monitored areas were analysed by scanning electron microscopy, equipped with a thin-window system for X-ray microanalysis (SEM/EDX). Photo-electron spectroscopy (XPS) was used to study the elemental composition of the particulate and to identify the chemical state of atomic species detected. Four clusters of particles for both “fine” and “coarse” fractions were identified: carbonaceous particles, soil erosion particles, Ca-sulphates and metal compound particles. EDX spectra showed that a percentage of carbonaceous particles carried S, Si and metal traces. High-resolution XPS spectra of the C1s region showed a significant greater occurrence of the C–O/C–N functional group in the particulate fine fraction collected in the smoking room compared to that collected outdoors. The carbonaceous component of coarse fraction collected in the smoking room appeared dissimilar from the same component detected in the other areas. After the 7-day absence of smokers this component of the PM10−2.1 fraction was similar to the corresponding coarse fraction collected at the outdoor location. The carbonaceous component of fine fraction collected in the smoking room, containing tobacco smoke products, such as organic carbon and nicotine, was traceable in the neighbouring areas, even several days after suspension of smoking activity.
Objective: Medication nonadherence presents a considerable problem in patients with schizophrenia. There are limited and conflicting data on the association of cognitive impairment with antipsychotic nonadherence. In this study, we evaluated the correlation of patients' scores on Mattis' Dementia Rating Scale (DRS; total and subscale scores) with scores on the Medication Management Ability Assessment (MMAA), a performance-based measure of medication management. Methods: Participants included 110 outpatients with schizophrenia or schizoaffective disorder. Each was evaluated using the MMAA role-play tasks and the DRS. Patients also completed the Drug Attitude Inventory (DAI), and the PANSS (Positive And Negative Syndrome Scale). Results: Age, DAI score, and DRS scores were all correlated with MMAA performance. In a stepwise regression analysis, only DRS scores were predictive of MMAA performance. Among the DRS subscales, conceptualization and memory were the best statistical predictors of MMAA performance. Conclusion: Cognitive functions, especially conceptualization and memory, were the strongest patient-related predictors of his or her ability to manage medications, over and above the effects of age, gender, education level, symptom severity, and attitudes toward medications. These results suggest a need for intervention studies focused on improving, or at least compensating for, specific cognitive deficits such as those in memory and conceptualization among patients with schizophrenia in order to improve their ability to manage medications.
The interfacial instabilities, including side reactions due to electrolyte decompositions and Cobalt (Co) dissolutions, are the main detrimental processes at LiCoO2 cathode when a high-voltage window (>4.2 V) is applied. Nevertheless, cycling the cathode with a voltage above 4.2 V would deliver an increased gravimetric capacity, which is desired for high power battery operation. To address these drawbacks, we demonstrate a synergistic approach by manufacturing the three-dimensional high-temperature LiCoO2 electrodes (3D HT-LCO) using laser-microstructuring, laser-annealing and subsequent coating with polymerized C60 thin films (C60@3D HT-LCO) by plasma-assisted thermal evaporation. The C60@3D HT-LCO cathode delivers higher initial discharge capacity compared to its theoretical value, i.e. 175 mA h g−1 at 0.1 C with cut-off voltage of 3.0–4.5 V. This cathode combines the advantages of the 3D electrode architecture and an advanced C60 coating/passivation concept leading to an improved electrochemical performance, due to an increased active surface area, a decreased charge transfer resistance, a prevented Co dissolution into the electrolyte and a suppressed side reaction and electrolyte decomposition. This work provides a novel solution for other cathode materials having similar concerns in high potential regimes for application in lithium-ion microbatteries.
We propose a model of lithium secondary batteries for analyzing both charging/ discharging characteristics and the increase of cell temperature in the case of the internal short circuit. We give an explanation to the experimental results of the nail penetration tests and discuss the structure-dependent properties of the batteries from the viewpoint of balance between energy density and safety. In particular, it is suggested that the thermal runaway in the nail penetration tests is determined by the total amount of Joule heat produced by the large current due to the internal short circuit until the discharge of the whole electrode is completed.
Supercapacitors (also known as ‘ultracapacitors’) offer a promising alternative approach to meeting the increasing power demands of energy-storage systems in general, and of portable (digital) electronic devices in particular. Supercapacitors are able to store and deliver energy at relatively high rates (beyond those accessible with batteries) because the mechanism of energy storage is simple charge-separation (as in conventional capacitors). The vast increases in capacitance achieved by supercapacitors are due to the combination of: (i) an extremely small distance that separates the opposite charges, as defined by the electric double-layer; (ii) highly porous electrodes that embody very high surface-area. A variety of porous forms of carbon are currently preferred as the electrode materials because they have exceptionally high surface areas, relatively high electronic conductivity, and acceptable cost. The power and energy-storage capabilities of these devices are closely linked to the physical and chemical characteristics of the carbon electrodes. For example, increases in specific surface-area, obtained through activation of the carbon, generally lead to increased capacitance. Since only the electrolyte-wetted surface-area contributes to capacitance, the carbon processing is required to generate predominantly ‘open’ pores that are connected to the bulk pore network. While the supercapacitors available today perform well, it is generally agreed that there is considerable scope for improvement (e.g., improved performance at higher frequencies). Thus it is likely that carbon will continue to play a principal role in supercapacitor technology, mainly through further optimization of porosity, surface treatments to promote wettability, and reduced inter-particle contact resistance.