batterydata/paper-abstracts huggingface dataset:
Polyamides (DTA-I, DTA-II, and DTA-III) containing cyclic disulfide structure were prepared by condensation between 1,2-dithiane-3,6-dicarboxylic acid (DTA) and alkyl diamine, NH2–(CH2) n –NH2 (DTA-I; n=4, DTA-II; n=6, DTA-III; n=8) and their application to positive active material for lithium secondary batteries was investigated. Cyclic voltammetry (CV) measurements under slow sweep rate (0.5mVs−1) with a carbon paste electrode containing the polyamide (DTA-I, DTA-II, or DTA-III) were performed. The results indicated that the polyamides were electroactive in the organic electrolyte solution (propylene carbonate (PC)-1,2-dimethoxyethane (DME), 1:1 by volume containing lithium salt, such as LiClO4). The responses based on the redox of the disulfide bonds in the polyamide were observed. Test cells, Li/PC-DME (1:1. by volume) with 1moldm−3 LiClO4/the polyamide cathode, were constructed and their performance was tested under constant current charge/discharge condition. The average capacity of the test cells with the DTA-III cathode was 64.3Ahkg−1 of cathode (135Whkg−1 of cathode, capacity (Ahkg−1) of the cathode×average cell voltage (2.10V)). Performance of the cell with linear polyamide containing disulfide bond (–CO–(CH2)2–S–S–(CH2)2–CONH–(CH2)8–NH–, GTA-III) was also investigated and the average capacity was 56.8Ahkg−1 of cathode (100Whkg−1 of cathode, capacity (Ahkg−1) of the cathode×average cell voltage (1.76V)). Cycle efficiency of the test cell with the DTA-III cathode was higher than that with the GTA-III cathode.
Studies on working memory (WM) dysfunction in schizophrenia have reported several functionally aberrant brain areas including prefrontal and temporal cortex. Longitudinal studies have shown changes in prefrontal activation during treatment. We used event-related functional magnetic resonance imaging and a parametric verbal WM task to investigate cerebral function during WM performance in healthy subjects and medicated patients with schizophrenia with an acute symptom exacerbation. Patients were scanned twice: within the first week after admission to the hospital and after 7–8 weeks of a multimodal treatment including atypical antipsychotic agents. There were no differences in activation of lateral prefrontal regions in patients relative to healthy controls neither at baseline nor after 7–8 weeks. Controls showed relatively more activation in parietal, striatal and cerebellar regions. In patients with schizophrenia, frontotemporal function was bilaterally enhanced after 7–8 weeks. This activation change was associated with improved accuracy in a verbal WM task, improved verbal WM-span and symptom reduction as measured by the BPRS global score and the BPRS factor for thought disturbance. Although we could not replicate findings of functional hypofrontality in the patients with schizophrenia, frontotemporal activation changed with treatment and was associated with verbal WM performance and significant reduction of psychopathology.
Ionic liquid (IL) and hybrid IL/organic electrolytes with pyrrolidinium cation based ILs have been investigated for application in high temperature lithium-ion batteries (HT-LIBs). The IL based electrolytes show high thermal stabilities, up to 340°C, ionic conductivities of >5×10−3 Scm−1 at 80°C, and broad electrochemical stability windows: 0–5V vs. Li+/Li°. The performance of LiFePO4 based half-cells at 80°C is promising, delivering ca. 160mAhg−1 at 1C, with a rate capability up to 4C and ca. 98% coulombic efficiency. The creation of hybrid IL/organic electrolytes by adding different organic cyclic carbonate solvents reduces viscosity of the electrolytes by 28% at 80°C, thereby improving the ion transport, and further improves the electrochemical performance; higher stability, better rate capability, and ≥99% coulombic efficiency. Overall, the electrolytes proposed have a potential to be applied in HT-LIBs, a concept with large advantages at the vehicle system level.
This article reports the recent research of electrodeposited Cu2O thin film as the new anode materials for thin film lithium ion battery. The cuprous oxide with pure cubic phase was successfully deposited by electrochemical deposition. The results of the assembled electrochemical cell tests indicated that electrodeposited cuprous oxide film permitted high electrochemical capacities and excellent cycle retention. After 50 cycles, the capacities still sustained at about 220mAh/g, and the decay was not significant except the first cycle. It is believed that the electrodeposition process is a convenient and inexpensive method compatible with the IC fabrication for preparing a novel anode material for thin film lithium ion battery, which will find possible application for miniaturized power source.
Thin films of lithium phosphorus oxynitride (Lipon) have been grown using a plasma-assisted, directed vapor deposition (PA-DVD) technique. In this approach, a high voltage electron beam is used to vaporize a Li3PO4 source and a supersonic, nitrogen-doped, helium gas jet then transport the vapor towards a substrate. A hollow cathode technique was then used to create an argon plasma just above the substrate. This sufficiently ionized the nitrogen in the gas jet to allow its incorporation into the Li3PO4 film reactively forming lithium phosphorus oxynitride. Increasing the nitrogen flux in the gas jet also increased the deposition rate from 113 to 178nmmin−1 for the deposition conditions used here, significantly reduced the pore volume fraction in the films and increased the N/P ratio from 0 to 0.75 as the gas jet nitrogen flux was increased from zero to 4.3×1018 moleculescm−2 s−1. Using substrate rotation, pore and columnar-free dense Lipon films could be grown by this method. The Li-ion conductivity increased from 3.7×10−9 to 5.2×10−7 Scm−1 as the nitrogen concentration was increased from zero to 2.1×1018 moleculescm−2 s−1 and was correlated with an increase in the film's Li/P ratio. An optimum nitrogen flux has been identified. As the nitrogen flux was increased above this value, the Lipon films suffered lithium loss and partial crystallization, resulting in a decrease in their Li-ion conductivity.
Li ion capacitor (LIC) has emerged as an exciting approach to synergistically combine low potential Li ion battery electrode with high potential supercapacitor electrode. Although wide cell potential window can be achieved through such coupling, current LICs continue to operate at a deliberately constricted cell potential window (2–3V) due to electrolyte degradation concerns caused by the presence of graphitic structure. Herein, highly stable 4V LIC with high energy and power density was rationally designed with 3D amorphous carbon positive electrode which demonstrated exceptional tolerance to high voltage as compared to graphitic carbon. The as-assembled 4V LIC, coupled with high capacity MnFe2O4/carbon negative electrode, exhibited remarkable capacity retention of 86.5% after cycling for 6000 cycles at 2Ag−1, with ca. 100% coulombic efficiency (indicating minimal electrolyte decomposition), while achieving high energy density of 157Whkg−1 at power density of 200Wkg−1. This work demonstrates the advantages of employing amorphous carbon as compared to more graphitic carbon as positive electrode and thus, serves as a guideline for designing stable 4V LIC with amorphous carbon.
Poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) (PTMA) is the most common active material with a stable radical molecular structure used for lithium rechargeable cells. Because it is an organic active material, PTMA can be dissolved easily in various solvents. Using a solution of active material in the electrode making process, we formed an extremely large surface area between the active material and the conducting additive. The electrode has excellent power capability and can be charged and discharged in 1min. We believe that this cell can be used like an electric double layer capacitor. We also believe that the cell, whose cycle life is good, retaining 89% of original capacity after 1000 cycles, can be put into practical use.
A modified zinc–manganese dioxide cell with a new cathodic active mass constitution was investigated. This modification improved all operational parameters of this cell, particularly voltage stability during discharge and increased electrical capacity of the cathode, making it competitive even with the better classified commercial “Heavy Duty” (HD) batteries based on zinc chloride electrolyte. Major benefits of this modification were: an improved voltage stability during discharge and a higher electrical capacity of the cathode.
Post-mortem studies have shown the maturation of the brain’s myelinated
white matter, crucial for efficient and coordinated brain communication, follows a nonlinear spatio-temporal pattern that corresponds with the onset and refinement of cognitive functions and behaviors. Unfortunately, investigation of myelination in vivo is challenging and, thus, little is known about the normative pattern of myelination, or its association with functional development. Using a novel quantitative magnetic resonance imaging technique sensitive to myelin we examined longitudinal white matter development in 108 typically developing children ranging in age from 2.5 months to 5.5 years. Using nonlinear mixed effects modeling, we provide the first in vivo longitudinal description of myelin water fraction development. Moreover, we show distinct male and female developmental patterns, and demonstrate significant relationships between myelin content and measures of cognitive function. These findings advance a new understanding of healthy brain development and provide a foundation from which to assess atypical development.
Background Aging is generally accompanied by changes in body composition, muscle mass and strength, leading to a decline in motor and functional performance. Physical activity and eating habits could be involved in modulating this paraphysiological deterioration. Aim of our study was to investigate changes in body composition, diet and physical performance in healthy, elderly females over a 3-year follow-up. Methods 92 healthy elderly females (70.9±4.0years) attending a twice-weekly mild fitness program were eligible for the study. They were assessed at baseline and again after 3years in terms of clinical history, diet, body composition by DEXA, resting energy expenditure, handgrip strength, knee extensor isometric/isotonic strength, and functional performance measured using the Short Physical Performance Battery (SPPB). Results After 3years, women had a significant decline in muscle strength (∆ isotonic: −1.4±4.3kg, ∆ isokinetic: −2.0±6.3kg, ∆ handgrip: −3.2±5.0kg; p<0.001) and physical performance (∆ walking time: 0.71±0.9s, ∆ walking speed: −0.25±0.35m/s; p<0.001), while their weight and body composition parameters did not change, except for a small decrease in appendicular skeletal muscle mass (−0.4±1.4kg). There was a significant drop in calorie (∆:−345.7±533.1kcal/d; p<0.001) and protein intake (∆:−0.14±0.23g/d; p<0.001), while resting energy expenditure remained stable. ∆ calorie intake correlated with the variation in 4-meter walking time (r: 0.34; p<0.01). Conclusions With advancing age, physical performance declines even in healthy, fit females despite a spare of weight and body composition. This decline in physical activity could lead to a lower calorie intake, which would explain why there is no variation in body weight.
A phase-inversion technique is introduced to produce a porous Sn anode for sodium batteries, which can accommodate volume changes during sodiation and desodiation. The Sn electrode shows two plateaus with a capacity of 1066 mAh g−1 during the first sodiation and four flat plateaus with a charge capacity of 674 mAh g−1 at the first desodiation process. During 500 cycles, the Sn electrode shows reversible capacity more than 519 mAh g−1 with Coulombic efficiency of nearly 99%. The Sn electrode with a porous structure is a possible solution to the electrode degradation.
Microtubule-associated protein tau is abnormally hyperphosphorylated, glycosylated, and aggregated in affected neurons in Alzheimer’s disease (AD). We recently found that the aberrant tau glycosylation precedes tau hyperphosphorylation in AD brain. In the present study, we developed assays to determine phosphorylation and dephosphorylation of tau at specific phosphorylation sites by using glycosylated tau purified from AD brain as a substrate. We then studied the effects of the aberrant glycosylation on phosphorylation and dephosphorylation of tau at each specific phosphorylation site. We found that deglycosylation of the aberrantly glycosylated tau decreased the subsequent phosphorylation of tau at Ser214, Ser262, and Ser356 in vitro by protein kinase A. On the other hand, deglycosylation of tau positively modulated the subsequent dephosphorylation by protein phosphatase 2A and protein phosphatase 5 in vitro at the phosphorylation sites Ser198, Ser199, and Ser202. Our results suggest that the aberrant glycosylation may modulate tau protein at a substrate level so that it is easier to be phosphorylated and more difficult to be dephosphorylated at some phosphorylation sites in AD brain. The combined impact of this modulation may be to make tau more susceptible to becoming abnormally hyperphosphorylated.
Accurately predicting the future health of batteries is necessary to ensure reliable operation, minimise maintenance costs, and calculate the value of energy storage investments. The complex nature of degradation renders data-driven approaches a promising alternative to mechanistic modelling. Here we show that a Bayesian non-parametric approach, using Gaussian process regression, can predict capacity fade in a variety of usage scenarios, forming a generalised health model. Our results are demonstrated on the open-source NASA Randomised Battery Usage Dataset, with data of 26 cells aged under widely varying operational conditions. Using half of the cells for training, and half for validation, we can accurately predict long term capacity fade, with a best case normalised root mean square error of 4.3%, including accurate estimation of the uncertainty of the prediction.
In this study, a phosphorus-free anolyte is prepared by using bicarbonate to replace phosphate buffer for application in two chamber microbial fuel cells (MFCs). Optical density test and Bradford protein assay shows that this phosphorus-free anolyte effectively inhibits the growth and reproduction of microorganisms suspended in the solution and greatly reduces the suspended cell mass. As a result, it considerably enhances the coulombic efficiency (CE) of MFCs. When the acetate concentration is 11 mM, the CE of the MFC using the pH 7 phosphate-containing anolyte is 9.7% and the CE with the pH 8.3 phosphate-containing anolyte is 9.1%, while the CE of the MFC using the phosphorus-free anolyte (pH 8.3) achieves 26.6%. This study demonstrates that this phosphorus-free anolyte holds the potential to enhance the feasibility for practical applications of MFCs.
We report a significant difference in the growth mechanism of Li2O2 in Li–O2 batteries for toroidal and thin-film morphologies which is dependent on the current rate that governs the electrochemical pathway. Evidence from diffraction, electrochemical, FESEM and STEM measurements shows that slower current densities favor aggregation of lithium peroxide nanocrystallites nucleated via solution dismutase on the surface of the electrode; whereas fast rates deposit quasi-amorphous thin films. The latter provide a lower overpotential on charge due to their nature and close contact with the conductive electrode surface, albeit at the expense of lower discharge capacity.
As anode materials for lithium-ion batteries, bicomponent metal oxide composites show high reversible capacities; but the morphology and particle size of the composites are hardly controllable, which may reduce their electrochemical properties. In this work, ultrathin NiO/NiFe2O4 nanoplates with a diameter of 5∼7nm and a thickness of ∼2nm are controllably fabricated on the graphene derived from NiFe layered double hydroxides (NiFe-LDHs), and exhibit superior electrochemical performance compared to pure NiO/NiFe2O4 aggregates without graphene. The nanosized NiO and NiFe2O4 plates are separated from each other and the graphene substrate can prevent the aggregation of NiO/NiFe2O4 as well as enhance the electronic conductivity of the composite, which is beneficial to improving the electrochemical performance. Moreover, the effects of the content and the particle size/component of NiO/NiFe2O4 on the electrochemical performances are also studied in order to achieve optimal performance. Ultrathin NiO/NiFe2O4 nanoplates are further encapsulated by graphene nanosheets and show slightly decreased performance compared to those supported by graphene nanosheets. The different electrochemical behaviors of graphene-containing composites may be attributed to the different interactions between graphene nanosheets and NiO/NiFe2O4 nanoplates.
This paper describes a systematic procedure, which includes analysis of strategy design criteria and development of real-time implementable strategy, to investigate the power management strategy for a range extended electric vehicle (RE–EV) using dynamic programming (DP). Since battery life is an important factor in replacement costs, battery energy losses are treated as one design criterion for battery protection. Fuel energy losses are another design criterion to address fuel economy. These two design criteria are expressed as two different cost functions for DP to evaluate both fuel-energy-loss-oriented and battery-energy-loss-oriented power management strategies. Considering driver comfort and battery life, limitations of noise, vibration, harshness, and battery charging/discharging currents are expressed as constraints in the DP process. Analysis results show that the fuel-energy-loss-oriented strategy can have better fuel economy, but its higher battery energy losses and average charging/discharging currents are unfavorable for battery life. On the contrary, battery-energy-loss-oriented strategy sacrifices some fuel economy in exchange for benefits to battery life. A rule-based, multi-mode switch strategy is then proposed as a power management strategy for RE–EV, which can require lower computation efforts. The proposed strategy employs a driving pattern recognition technique of switching among the control rule sets extracted from DP results of each representative driving pattern. Simulation results using three untrained driving patterns show that the proposed strategy improves the control performance of fuel economy and battery protection compared to that of conventional thermostat control strategy.
Spinel LiMn2O4 is considered to be a promising cathode for lithium-ion batteries owing to its low cost, safety, environmental friendliness, high operating voltage and natural abundance of manganese. However, the accelerated dissolution of manganese at elevated temperature results in serious capacity fading, which inhibits its further application in energy storage systems. The dissolution of manganese is mainly caused by the attack of trace acidic species (HF) in liquid electrolyte. Here, we report a facile, universal and effective strategy to suppress the dissolution of manganese at 55 °C by encapsulating LiMn2O4 particles in crumpled Ti3C2Tx nanosheets using an electrostatic self-assembly process. With high electronic conductivity and fast Li+ transport capability, such protective layer reduces direct contact between liquid electrolyte and LiMn2O4 particles, suppressing the dissolution of manganese. The composite exhibits larger discharge specific capacity, enhanced rate and cycling capabilities. The capacity retention ratio can be improved by 18.3% at 55 °C after 200 cycles at 2 C. This study provides a new strategy for suppressing the dissolution of manganese at high temperature and widens the road for the application of 2D MXene in energy storage field. The electrostatic self-assembly strategy we proposed is universal and can be applied in other cathode materials, which can arouse much interest of relevant researchers.
It is usually uneconomic to provide mains power to small remote communities even when high voltage lines pass by a village. Local authorities normally resort to diesel-powered generators which require expensive fuel which is difficult to bring into remote areas. Furthermore they are noisy and require frequent maintenance which is often neglected in remote areas due to limited resources and know-how. Neither wind nor sun provides reliable power in humid tropical regions where there is a lot of still and overcast weather. Towers are found to attract lightning strikes which can destroy electronic controls, fungus grows on solar panels, and the multiple electrical connections on photovoltaic arrays corrode away in hot, humid climates. Micro hydro is an attractive option in mountainous areas, and a 30kW high head and a 3kW low head plant have been built, using village labour and surplus and discarded materials. Both are operating satisfactorily. However conventional micro hydro is not possible in flat country where there is little elevation, and work is now in progress to evaluate suitable hydrokinetic turbines on rivers in the humid tropics. Numerous companies around the world are now developing hydrokinetic turbines to harvest tidal and river flows, but a major problem with most designs is clogging by floating debris, especially in tropical rivers.
A Silicon nanowire (SiNW) array inserted into flexible poly-dimethylsiloxane (SiNW array/PDMS) composite structure as anode with high capacity and long-term cycling stability is synthesized by a cost-effective and scalable method. In this structure, the aggregation and fracture of SiNWs are alleviated by the flexible PDMS skeleton. Act as the main active component, the SiNWs are coated by loose SiO2 shells. These loose SiO2 shells not only provide space for the large volume changes of SiNW, but also react with the electrolyte and form the stable protective layer during the processes of the lithiation and delithiation. These two functions could improve the cycling stability and columbic efficiency of the SiNWs. The as-obtain flexible SiNW array/PDMS composite structure exhibits excellent long-term cycling stability with a specific capacity of 887.2mA·h·g−1 and capacity retention of ∼83.4% over 350 cycles at 0.5C rate compared with the fifteenth cycle. The design of this new structure provides a potential way for developing other functional composite materials.
Reformulation of electrolyte systems and improvement of separator wettability are vital to electrochemical performances of rechargeable lithium (Li) metal batteries, especially for suppressing Li dendrites. In this work we report a bifunctional electrolyte additive that improves separator wettability and suppresses Li dendrite growth in Li metal batteries. A triblock polyether (Pluronic P123) is added as an additive into a commonly used carbonate-based electrolyte. It is found that addition of 0.2–1% (by weight) P123 into the electrolyte can effectively enhance the wettability of polyethylene separator. More importantly, the adsorption of P123 on Li metal surface can act as an artificial solid electrolyte interphase layer and suppress the growth of Li dendrites. A smooth and dendrite-free Li morphology can be achieved in the electrolyte with 0.2% P123. The Li||Li symmetric cells with the 0.2% P123-containing electrolyte exhibit a relatively long cycling stability at high current densities of 1.0 and 3.0 mA cm−2.