batterydata/paper-abstracts huggingface dataset:
Local current density is an important parameter in battery modeling, which affects the performance of lithium-ion batteries. In this study, we take LiFePO4 cathode material as an example. A simplified mathematical model has been developed to study the internal mechanism of the electrode. According to the results of the model, the local current density distribution has a regular change at different time in the discharge process. The parameter “critical thickness” as an optimized variable has been presented for battery design. By qualitative analysis to estimate the critical thickness under different condition, we can optimize the design parameter of a battery according to the practical demand.
Novel sandwich-structured silicon-based anodes have been prepared to inhibit the fragmentation of silicon electrodes typically caused by the large volume changes that occur during charge/discharge processes. An electrostatic self-assembly method and hydrothermal dehydration are used to introduce a reduced graphene oxide layer (rGO) on the surface of silicon/carbon nanofibers (Si/CNFs), which prevent the exfoliation of nano-Si from the electrode bulk to the liquid electrolyte, reduce the electric contact loss, stabilize the electrode’s structural integrity, and improve electrochemical conductivity. The Si/CNFs@rGO exhibit superior electrochemical performance as an anode, retaining a high specific capacity of 1055.1mAhg−1 up to 130 cycles at 0.1Ag−1, with slight capacity loss. The Si/CNFs@rGO electrode also demonstrates outstanding rate behavior with a reversible capacity of 358.2mAhg−1 at 5Ag−1. Results indicate that the graphene layer significantly improves the electrochemical performance of the silicon/carbon nanofiber electrode.
Computational screening is a powerful tool used to identify solvents for application in EDLC electrolytes. One of the solvents recently introduced by this method, 3-cyanopropionic acid methyl ester, is herein successfully tested as electrolyte in combination with the salt 1-butyl-1-methylpyrrolidinium tetrafluoroborate ([Pyr14][BF4]). High salt concentrations, as well as operative voltages of 3.0V are possible with this combination, proving that this new solvent is indeed a promising new candidate for a new class of electrolyte materials for EDLCs.
In vertebrate development the Dickkopf protein family carries out multiple functions and is represented by at least four different genes with distinct biological activities. In invertebrates such as Drosophila and Caenorhabditis, Dickkopf genes have so far not been identified. Here we describe the identification and characterization of a Dickkopf gene with a deduced amino acid sequence closely related to that of chicken Dkk-3 in the basal metazoan Hydra. HyDkk-3 appears to be the only Dickkopf gene in Hydra. The gene is expressed in the gastric region in nematocytes at a late differentiation stage. In silico searches of EST and genome databases indicated the absence of Dkk genes from the protostomes Drosophila and Caenorhabditis, whereas within the deuterostomes, a Dkk-3 gene could be identified in the genome of the urochordate Ciona intestinalis. The results indicate that at an early stage of evolution of multicellularity Dickkopf proteins have already played important roles as developmental signals. They also suggest that vertebrate Dkk-1, 2 and 4 may have originated from a common ancestor gene of Dkk-3.
The relations among driving-related psychosocial measures (e.g., driving comfort, attitudes toward driving) and measures of self-reported health were examined in the context of driver characteristics (i.e., age and gender) within the Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive II) baseline data, available for the cohort of 928 drivers, 70 years of age and older. Older members of the cohort had lower comfort scores and poorer perceptions of their driving abilities. Men reported significantly higher levels of driving comfort than women. When analyses including health were controlled for age and gender, significant relations with health status were evident for most of the psychosocial measures. These findings extend previous research and suggest that attitudes, beliefs, and perceptions about driving may be influenced by health status and act as mediators in the self-regulation process.
The electrochemical properties of graphene are strongly depending on its synthesis. Between the different methods proposed so far, liquid phase exfoliation turns out to be a promising method for the production of graphene. Unfortunately, the low yield of this technique, in term of solid material obtained, still limit its use to small scale applications. In this article we propose a low cost and environmentally friendly method for producing multilayer crystalline graphene with high yield. Such innovative approach, involving an improved ionic liquid assisted, microwave exfoliation of expanded graphite, allows the production of graphene with advanced lithium ion storage performance, for the first time, at low temperatures (<0 °C), as low as −30 °C, with respect to commercially available graphite.
In this paper we report a novel architecture of hierarchical 3D porous carbon microspheres (PCM) to encapsulate ZnO-CoO nanoparticles that serves as an advanced anode for high-performance lithium-ion battery (LIB). The PCM is fabricated by a facile aerosol spray pyrolysis method, and ZnO-CoO composite nanoparticles are infiltrated into the PCM by a simple one-pot hydrothermal procedure (i.e., ZnO-CoO@PCM). The developed hybrid material provides several advantages: (1) partial replacement of CoO with ZnO to offer a low-cost and eco-friendly candidate anode, (2) a continuous and large surface area (1236 m2 g−1) carbon network for improved electrical conductivity and uniform dispersion of ZnO-CoO nanoparticles, and (3) porous structure for good electrolyte diffusion and fast Li-ion transport and to buffer the large volume expansion of the metal oxides. As a result, this new ZnO-CoO@PCM nanocomposite demonstrates a higher reversible capacity (1250 mAh g−1 after 150 cycles at a current density of 100mAg−1), more excellent cycling stability, and better rate capability than a ZnO-CoO/PCM mixture and than a non-porous ZnO-CoO/carbon black mixture. The 3D porous nanocomposite architecture in this work could shed light on the design and synthesis of other metal oxides electrodes for energy storage.
On the basis of extreme similarity between the triangle phase diagrams of LiNiO2–LiTiO2–Li[Li1/3Ti2/3]O2 and LiNiO2–LiMnO2–Li[Li1/3Mn2/3]O2, new Li–Ni–Ti–O series with a nominal composition of Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0≤ z ≤0.5) was designed and attempted to prepare via a spray-drying method. XRD identified that new Li–Ni–Ti–O compounds had cubic rocksalt structure, in which Li, Ni and Ti were evenly distributed on the octahedral sites in cubic closely packed lattice of oxygen ions. They can be considered as the solid solution between cubic LiNi1/2Ti1/2O2 and Li[Li1/3Ti2/3]O2 (high temperature form). Charge–discharge tests showed that Li–Ni–Ti–O compounds with appropriate compositions could display a considerable capacity (more than 80mAhg−1 for 0.2≤ z ≤0.27) at room temperature in the voltage range of 4.5–2.5V and good electrochemical properties within respect to capacity (more than 150mAhg−1 for 0≤ z ≤0.27), cycleability and rate capability at an elevated temperature of 50°C. These suggest that the disordered cubic structure in some cases may function as a good host structure for intercalation/deintercalation of Li+. A preliminary electrochemical comparison between Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0≤ z ≤0.5) and Li6/5Ni2/5Ti2/5O2 indicated that charge–discharge mechanism based on Ni redox at the voltage of >3.0V behaved somewhat differently, that is, Ni could be reduced to+2 in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 while+3 in Li6/5Ni2/5Ti2/5O2. Reduction of Ti4+ at a plateau of around 2.3V could be clearly detected in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 with 0.27≤ z ≤0.5 at 50°C after a deep charge associated with charge compensation from oxygen ion during initial cycle.
The power electronic subsystems within electric vehicle (EV) powertrains are required to manage both the energy flows within the vehicle and the delivery of torque by the electrical machine. Such systems are known to generate undesired electrical noise on the high voltage bus. High frequency current oscillations, or ripple, if unhindered will enter the vehicle’s battery system. Real-world measurements of the current on the high voltage bus of a series hybrid electric vehicle (HEV) show that significant current perturbations ranging from 10Hz to in excess of 10kHz are present. Little is reported within the academic literature about the potential impact on battery system performance and the rate of degradation associated with exposing the battery to coupled direct current (DC) and alternating currents (AC). This paper documents an experimental investigation that studies the long-term impact of current ripple on battery performance degradation. Initial results highlight that both capacity fade and impedance rise progressively increase as the frequency of the superimposed AC current increases. A further conclusion is that the spread of degradation for cells cycled with a coupled AC–DC signal is considerably more than for cells exercised with a traditional DC waveform. The underlying causality for this degradation is not yet understood. However, this has important implications for the battery management system (BMS). Increased variations in cell capacity and impedance will cause differential current flows and heat generation within the battery pack that if not properly managed will further reduce battery life and degrade the operation of the vehicle.
An intimate hybrid of carbon black/nickel cobaltite (CB/NCO) is rationally designed and successfully synthesized via a facile two-step method. Due to the unique nanostructure and strong synergistic effects between individual components, the CB/NCO hybrid electrode delivers distinctly enhanced energy-storage properties, including a high specific capacity (604.4Cg−1 at 0.5Ag−1) and excellent rate capability (∼77.3% and 62.4% of initial capacity at 10Ag−1 and 20Ag−1, respectively). The excellent energy-storage properties of this low-cost hybrid can stand comparison with the hybrids of NiCo2O4 with various costly nanocarbons. An asymmetric supercapacitor (ASC) is constructed using CB/NCO hybrid and activated carbon as the positive and negative electrode, respectively. The assembled ASC device exhibits a maximum energy density of 33.7Whkg−1 and a high power density of 12.2kWkg−1. Meanwhile, the ASC device also shows a satisfactory long cycle-life and long-term stability (∼90% capacitance retention after 50,000 charge-discharge cycles at 5Ag−1). On the premise of cost control, such a strategy may enlighten new design opportunities for high-performance energy storage devices based on inexpensive carbon-based materials.
Amorphous Mg0.9−x Ti0.1Pd x Ni (x =0.04–0.1) hydrogen storage alloys were prepared by mechanical alloying (MA). The effects of Pd substitution on the electrochemical properties of the Mg0.9−x Ti0.1Pd x Ni (x =0.04–0.1) electrode alloys were studied by cyclic charge–discharge, linear polarization, anodic polarization, electrochemical impedance spectroscopy (EIS), and hydrogen diffusion coefficient experiments. It was found that the cyclic capacity retention rate C 50/C 1 of the quaternary alloys was greatly improved due to the substitution of Pd for Mg. Mg0.8Ti0.1Pd0.1Ni electrode alloy retained the discharge capacity above 200mAhg−1 even after 80 charge–discharge cycles, possessing the longest cycle life in the studied quaternary alloys. The improvement of cycle life was ascribed to the formation of passive film on the surface of these electrode alloys. X-ray photoelectron spectroscopy (XPS) analysis proved that the passive film was composed of Mg(OH)2, TiO2, NiO, and PdO, which synergistically protected the alloy from further oxidation. The Auger Electron Spectroscopy (AES) study revealed that the thickness of passive film increased with augmentation of the Pd content. The electrochemical impedance study of electrode alloys after different cycles demonstrated that the passive film became thicker during cycles and its thickness also increased with Pd content augmentation. It was also found that the augmentation of Pd content resulted in the decrease of exchange current density I 0 and the increase of the charge-transfer resistance R ct. With increasing the Pd amount in the Mg0.9−x Ti0.1Pd x Ni (x =0.04–0.1) electrode alloys, hydrogen diffusion coefficient D was gradually enhanced at first. Then, it decreased with augmentation of cycle due to the growth of passive film on the surface of the alloys.
Mechanical degradation caused by lithiation/delithiation-induced stress and large volume change is the primary cause of fast capacity fading of silicon (Si)-based electrodes. Although intensive efforts have been devoted to understanding electromechanically induced fractures of electrodes made of Si alone (e.g., Si particles, Si thin films, and Si wafers), the cracking behavior of Si/polymeric binders/carbon black composite electrodes is unclear and poorly understood. Here, we investigate, by in situ and ex situ techniques, the cracking behavior of Si composite electrodes made with different binders, including polyvinylidene fluoride (PVDF), sodium-alginate (SA), sodium-carboxymethyl cellulose (Na-CMC), and Nafion. We found that extensive cracks form during the 1st delithiation process, which periodically open and close during subsequent lithiation/delithiation cycles at the same locations in the Si composite electrodes made with SA, Na-CMC, and Nafion. In contrast, a significantly fewer number of cracks form in the Si/PVDF electrodes after electrochemical cycling. A possible mechanism is proposed to help understand the effects of binders on the cracking behavior (e.g., crack spacing and island size) of Si composite electrodes. We also suggest possible approaches, including reducing the electrode thickness, patterning electrodes, and using highly recoverable binders, to inhibit cracks and improve the mechanical integrity of Si composite electrodes.
Concerning the large interfacial resistance of materials within solid-stated batteries (SSBs) caused by the unstable solid contact, an assistant ionic conductor is introduced to improve the interfacial Li+ transport of SSBs. The assistant ionic conductor is achieved by impregnating an ionic liquid (Li-IL) into a porous metal-organic framework (MOF) host. When integrated with LLZO solid-state electrolyte (SSE), the solidified Li-IL guest can make direct contact with the LLZO particles through the open channels in MOF host, which changes the original unstable solid-solid contact into “nanowetted” interfaces to boost Li+ transport. Benefited from the unique nanowetted interfaces, the hybrid SSE demonstrates a high ionic conductivity of 1.0 × 10−4 S cm−1 with a wide electrochemical window of 5.2 V, and also exhibits excellent compatibility with Li metal anode. Furthermore, the LLZO based LiCoO4 and LiFePO4 SSBs with the ionic conductor additive to favor the interfacial Li+ transport achieve high capacity retention of 97% after 150 cycles with reasonable rate capability. The good electrochemical performance is attributed to the effective Li+ transport networks established inside the SSBs by the ionic conductor through the nanowetted interfacial mechanism, which is proved to be a promising approach to the safe and high-power energy storage.
This paper develops a general model with which to evaluate flow uniformity and pressure drop within interdigitated-channel structures, especially in the context of redox flow batteries. The governing equations are cast in dimensionless variables, leading to a set of characteristic dimensionless parameter groups. The systems of governing equations are solved computationally, with the results presented graphically. Because the results are general, the underlying model itself is not needed to apply the quantitative design guidelines. However, the paper presents and discusses all the information required to recreate the model as needed.
Carbon beads have been prepared by the carbonization of naphthalene sulfonate formaldehyde (NSF) resin. The procedures for the preparation have been described in detail. The electrochemical performance of NSF carbon beads as an anode material for lithium batteries has been correlated with some carbonization factors such as the molecular weight of the precursor, the ramp rate, and final temperature, etc.
The electrochemistry of Sn–Cu–C nanocomposite anode materials in Na-ion cells is described and compared directly to similar compositions from previous work in Li-ion cells. A series of compositions corresponding to (Cu6Sn5)1−x C x (x =0.15–0.52) was prepared by combinatorial sputtering. This composition range has been shown previously to have good cycling performance in Li-ion cells, having stable capacities near 600mAh/g for 0.15< x <0.45. In contrast, the same composition range was found to have reduced capacity when used in Na-ion cells, having just 350mAh/g when x =0.15. Further addition of carbon results in a reduction of reversible capacity to just 135mAh/g when x =0.44, however this alloy retains 99% of its 10th cycle capacity of 117mAh/g after 50 cycles. The potential use and the impact of the addition of carbon to alloy negative electrodes containing Sn for Na-ion batteries are discussed.
A field experiment was conducted to evaluate the combined or individual effects of biochar and nitrapyrin (a nitrification inhibitor) on N2O and NO emissions from a sandy loam soil cropped to maize. The study included nine treatments: addition of urea alone or combined with nitrapyrin to soils that had been amended with biochar at 0, 3, 6, and 12 t ha−1 in the preceding year, and a control without the addition of N fertilizer. Peaks in N2O and NO flux occurred simultaneously following fertilizer application and intense rainfall events, and the peak of NO flux was much higher than that of N2O following application of basal fertilizer. Mean emission ratios of NO/N2O ranged from 1.11 to 1.72, suggesting that N2O was primarily derived from nitrification. Cumulative N2O and NO emissions were 1.00 kg N2O-N ha−1 and 1.39 kg NO-N ha−1 in the N treatment, respectively, decreasing to 0.81–0.85 kg N2O-N ha−1 and 1.31–1.35 kg NO-N ha−1 in the biochar amended soils, respectively, while there was no significant difference among the treatments. NO emissions were significantly lower in the nitrapyrin treatments than in the N fertilization-alone treatments (P < 0.05), but there was no effect on N2O emissions. Neither biochar nor nitrapyrin amendment affected maize yield or N uptake. Overall, our results showed that biochar amendment in the preceding year had little effect on N2O and NO emissions in the following year, while the nitrapyrin decreased NO, but not N2O emissions, probably due to suppression of denitrification caused by the low soil moisture content.
Aberrant salience may explain hasty decision making and psychotic symptoms in schizophrenia. In healthy individuals, final decisions in probabilistic reasoning tasks are related to Nucleus accumbens (Nacc) activation. However, research investigating the Nacc in social decision making is missing. Our study aimed at investigating the role of the Nacc for social decision making and its link to (aberrant) salience attribution. 47 healthy individuals completed a novel social jumping-to-conclusion (JTC) fMRI-paradigm, showing morphed faces simultaneously expressing fear and happiness. Participants decided on the ‘current’ emotion after each picture, and on the ‘general’ emotion of series of faces. Nacc activation was stronger during final decisions than in previous trials without a decision, particularly in fear rather than happiness series. A JTC-bias was associated with higher Nacc activation for last fearful, but not last happy faces. Apparently, mechanisms underlying probabilistic reasoning are also relevant for social decision making. The pattern of Nacc activation suggests salience, not reward, drives the final decision. Based on these findings, we hypothesize that aberrant salience might also explain social-cognitive deficits in schizophrenia.
Abnormal auditory neuromagnetic M50 and M100 responses, reflecting primary/secondary auditory cortex processing, have been reported in children who have autism spectrum disorder (ASD). Some studies have reported an association between delays in these responses and language impairment. However, as most prior research has focused on verbal individuals with ASD without cognitive impairment, rather little is known about neural activity during auditory processing in minimally verbal or nonverbal children who have ASD (ASD-MVNV)—children with little or no speech and often significant cognitive impairment. To understand the neurophysiological mechanisms underlying auditory processing in ASD-MVNV children, magnetoencephalography (MEG) measured M50 and M100 responses arising from left and right superior temporal gyri during tone stimuli in three cohorts: (1) MVNV children who have ASD (ASD-MVNV), (2) verbal children who have ASD and no intellectual disability (ASD-V), and (3) typically developing (TD) children. One hundred and five participants (8–12 years) were included in the final analyses (ASD-MVNV: n = 16, 9.85 ± 1.32 years; ASD-V: n = 55, 10.64 ± 1.31 years; TD: n = 34, 10.18 ± 1.36 years). ASD-MVNV children showed significantly delayed M50 and M100 latencies compared to TD. These delays tended to be greater than the corresponding delays in verbal children with ASD. Across cohorts, delayed latencies were associated with language and communication skills, assessed by the Vineland Adaptive Behavior Scale Communication Domain. Findings suggest that auditory cortex neural activity measures could be dimensional objective indices of language impairment in ASD for either diagnostic (e.g., via threshold or cutoff) or prognostic (considering the continuous variable) use.
Debate remains on whether hypercholesterolemia is associated with cognitive impairment. Hence, we investigated whether poorly controlled cholesterol impairs functional connectivity among patients with type 2 diabetes mellitus (T2DM).
Mechanical properties and failure mechanisms of battery separators play a crucial role in integrity of Lithium-ion batteries during an electric vehicle crash event. In this study, four types of commonly used battery separators are characterized and their mechanical performance, strength, and failure are compared. This includes two dry-processed polyethylene (PE) and trilayer separators, a wet-processed ceramic-coated separator, and a nonwoven separator. In detail, uniaxial tensile tests were performed along machine direction (MD), transverse direction (TD) and diagonal direction (DD). Also, through-thickness compression tests and biaxial punch tests were conducted. Comprehensive mechanical tests revealed interesting deformation and failure patterns under extreme mechanical loads. Last, a finite element model of PE separator was developed in LSDYNA based on the uniaxial tensile and through-thickness compression test data. The model succeeded in predicting the response of PE separator under punch tests with different sizes of punch head.