batterydata/paper-abstracts huggingface dataset:
Dimethyl fumarate is a fumaric acid ester. It has been used for some years to treat psoriasis and also as a preservative in desiccant sachets in the transport of furniture and footwear. Its irritant properties and sensitizing potential in contact with the skin were recently highlighted when it was implicated as the causative agent in 2 epidemics of severe acute eczema: sofa dermatitis in northern Europe and shoe dermatitis in Spain. The present article aims to guide dermatologists in the diagnosis and management of patients allergic to dimethyl fumarate. We review the clinical manifestations, results of patch tests, possible cross-reactions, and sources of exposure to dimethyl fumarate responsible for these skin reactions.
New types of composite, solvent-free lithium ion conducting polymer electrolytes have been prepared by dispersing two complementary additives to a PEO–LiX (LiX=LiCF3SO3) matrix. The additives have been chosen in such a way that one of them (calix(6)pyrrole) enhances the lithium ion transference number while the other (super-acid zirconia) enhances the conductivity of the electrolyte. The results demonstrate that these dual-composite polymer electrolytes have a high conductivity with significantly high lithium transference number. This rare combination makes the new polymer electrolytes of interest for the development of advanced, solid-state, lithium polymer batteries.
A Li-ion polymer pouch cell battery design for a spacesuit developed an internal short during ground storage. A detailed failure investigation found that native contamination was the most probable root cause as the failure mechanism was successfully replicated. Lessons learned are applicable to the implementation of most Li-ion cell designs for critical applications.
The purpose of the study was to evaluate the prevalence of insomnia in multiple sclerosis patients with comorbid depression, associations between psychological symptoms, multiple sclerosis symptoms and insomnia, and to test effects of a 16-week protocol-based psychotherapy intervention for depression on insomnia symptoms. Participants with multiple sclerosis and depression (n = 127) were randomized to telephone administered cognitive behavioral therapy and telephone administered supportive emotion-focused therapy. Multiple sclerosis functional limitation was measured at baseline. Depression, insomnia, anxiety and quality of life were evaluated at pre treatment, mid treatment (8 weeks), and post treatment (16 weeks). Prevalence of insomnia ≥3 times per week was 78% at pre treatment and 43% at post treatment. Insomnia at baseline was associated with depression, multiple sclerosis related mood symptoms and anxiety. Middle of the night awakenings were associated with swallowing and speech problems. Improvements in insomnia were associated with improvement in depression and anxiety. Participants with residual insomnia were more likely to have major depressive disorder, greater multiple sclerosis severity, elevated anxiety and lower mental components of quality of life. Results demonstrate rates of insomnia in patients with comorbid multiple sclerosis and depression are higher than those reported in the general multiple sclerosis population and additional insomnia treatment is indicated beyond the treatment of comorbid psychological disorders.
Energy storage systems utilizing a simultaneous intercalation of anions into a graphite host structure at the positive electrode and intercalation/insertion/reduction or deposition of cations at the negative electrode during charge, were introduced under the term dual-ion cells, recently. In this work, the electrochemical intercalation of TFSI− anions into graphite has been studied in sodium‐based dual‐ion cells (SDICs) at different upper cut‐off potentials varying between 4.5V and 4.7V vs. Na/Na+. Electrochemical characteristics of SDICs, including the reversible capacity, Coulombic efficiency, energy efficiency and onset potentials for anion intercalation, were evaluated in comparison to the lithium-based dual-ions cells (LDICs). A stable charge/discharge cycling performance over 500 cycles has been found for SDICs providing a specific capacity of ≈ 32mAh g‐1 and a Coulombic efficiency exceeding 99% at an upper cut‐off potential of 4.7 V vs. Na/Na+ at the graphite cathode. By the addition of the electrolyte additive ethylene sulfite (ES), an increase of the reversible capacity to ≈ 46mAhg‐1 was achieved. Furthermore, possible reasons for the overall inferior cycling performance in terms of capacity for SDICs as compared to LDICs such as an increased overpotential for plating/stripping of Na+ ions as compared to Li+ ions are discussed. In this respect, we also found that the addition of ethylene sulfite particularly decreases the overpotentials for the metal plating process, which at least partially explains the enhanced reversible capacity in LDICs and SDICs by using ES as electrolyte additive.
In this work, a LiFe0.5Mn0.5PO4/C (LFMP/C) material was prepared by a simple solid-state ball-mill method by using LiH2PO4, γ-MnO2, and hollow α-Fe2O3 nano-sized materials. Both γ-MnO2 and hollow α-Fe2O3 were synthesized by a hydrothermal process. LFMP/C composites coated with different amounts (1–3wt%) of Li4Ti5O12 (LTO) were synthesized by a sol-gel method. Their typical properties are studied using X-ray diffraction, micro-Raman spectroscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy, transmission electron microscopy, the AC impedance method, and the galvanostatic charge–discharge method. The results revealed that a 1 wt%-LTO-coated LFMP/C composite shows the highest performance among all LFMP/C composite samples. The long-term cycling performance of the LFMP/C composite improves considerably when the LTO ionic conductor is applied on it. Moreover, the 1 wt%-LTO-coated LFMP/C composite, which has the lowest fading rate, maintains high cycling stability at 1 C (141 mAh g−1) and 10 C (133 mAh g−1) at 55 °C after 100 cycles; by contrast, a bare LFMP/C sample, which demonstrates the highest fading rate, exhibits an unfavorable life cycle, and its discharge capacity decreases rapidly. The ionic conductor coating thus improves the high-temperature performance of LFMP/C composites. A LFMP/C-KS6/SiO2 full cell is assembled and tested.
The performance of a LiNiO2-based cell has been shown to be significantly improved by Mg-doping of LiNi0.8Co0.15Al0.05O2 (Mg-doped NCA) cathode materials. In the present study, the effects of Mg-doping were examined by electrochemical impedance spectroscopy (EIS) and scanning transmission electron microscopy-electron energy loss spectroscopy. EIS analysis revealed that the activation energy of Mg-doped NCA for the charge-transfer reaction was larger than that of undoped NCA by a factor of ∼10%; however, the charge-transfer resistance for Mg-doped NCA did not vary significantly with cycling, suggesting a different microstructure evolution compared to that of the undoped NCA. The spatial mapping of the product phases in the Mg-doped samples showed less degradation after charge–discharge cycling tests at 70°C compared to that in the undoped samples. In addition, degraded regions observed near the surface of the primary active material particles were identified as an intermediate structure, containing tetrahedrally coordinated Ni in contrast to the NiO-like phase found in the undoped samples. These microstructural observations are consistent with the electrochemical measurements.
The structure of two amphiphilic low-dimensional copolymer electrolytes I of similar overall composition but prepared by different synthetic procedures is described. I are copolymers of poly [2,5,8,11,14-pentaoxapentadecamethylene(5-alkyloxy-1,3-phenylene)] (CmO5) and poly[2,-oxatrimethylene(5-alkyloxy-1,3-phenylene)] (CmO1) where the alkyl side chains having m carbons are mixed dodecyl/octadecyl (50/50). 1H NMR shows that the copolymers have only 18 and 13% of CmO5 units in which LiBF4 ions are separated by Li+ encapsulation in tetraethoxy segments but molecular modelling suggests that in ionophobic CmO1 units the salt is mostly present as neutral aggregates decoupled from the polymer. Conductivities of microphase-separated mixtures with salt-bridge amphiphilic polyethers II and III of each system are similar. They have low temperature dependence over the range 20–110°C at ∼10−3 Scm−1. A conduction mechanism is proposed whereby Li+ hopping takes place along rows of decoupled aggregates in an essentially block copolymer structure. Subambient measurements to −10°C gave a conductivity of 4×10−5 Scm−1.
Rechargeable batteries can effectively store electrical energy as chemical energy, and release it when needed, providing a good choice for applications in electric vehicles (EVs). Naturally, safety concerns are the key issue for the application of battery technology in EVs. Olivine LiFePO4 is considered to be the most promising cathode material for lithium-ion batteries due to its environmental friendliness, high cycling performance and safety characteristics. Some important breakthroughs in recent years have allowed its successful commercialization. However, in spite of its success, the commercial application of LiFePO4 batteries in EVs is still hindered by some technological obstacles. Herein, we provide an update on our previous review, and overview the most significant advances in the remaining challenges for this promising battery material. New research directions and future trends have also been discussed.
Self-discharge is a significant issue in electric double layer energy storage, which leads to a rapid voltage drop and low energy efficiency. Here, we attempt to solve this problem by changing the structure of the electric double layer into a de-solvated state, by constructing a nano-scale and ion-conductive solid electrolyte layer on the surface of a carbon electrode. The ion concentration gradient and potential field that drive the self-discharge are greatly restricted inside this electric double layer. Based on this understanding, a high-efficiency graphene-based lithium ion capacitor was built up, in which the self-discharge rate is reduced by 50% and the energy efficiency is doubled. The capacitor also has a high energy density, high power output and long life, and shows promise for practical applications.
The electrochemical impedance responses for different laboratory type metal hydride electrodes were successfully modeled and fitted to experimental data for AB5 type hydrogen storage alloys as well as one MgNi type electrode. The models fitted the experimental data remarkably well. Several AC equivalent circuits have been proposed in the literature. The experimental data, however, could not always be satisfactorily approximated. The approximation model presented here exhibits smooth fit to the experimental results for all frequencies in the whole range from 10 kHz to 0.1 mHz. Equivalent circuits, explaining the experimental impedances in a wide frequency range for electrodes of hydride forming materials mixed with copper powder, were obtained. Both charge transfer and spherical diffusion of hydrogen in the particles are important sub processes that govern the total rate of the electrochemical hydrogen absorption/desorption reaction. To approximate the experimental data, equations describing the current distribution in porous electrodes were needed. Indications of one or more parallel reduction/oxidation processes competing with the electrochemical hydrogen absorption/desorption reaction were observed. The impedance analysis was found to be an efficient method for characterizing metal hydride electrodes in situ.
Zn-doped Li3V2(PO4)3/C (Li3V2−x Zn x (PO4)3/C, x = 0, 0.02, 0.04 and 0.06) cathode materials are synthesized by an improved sol–gel method of which pH value is controlled at 4. They are characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, linear sweep voltammetry, galvanostatic charge/discharge test, cyclic voltammetry, electrochemical impedance spectroscopy and potential step chronoamperometry. Li3V1.96Zn0.04(PO4)3/C has the highest electrical conductivity among the four samples. Although the initial discharge capacity for the doped samples at low current rate, such as 0.2C, presents no obvious enhancement compared with that for the undoped one, the cyclability and the rate performance are improved significantly. Zn-doped samples exhibit higher initial discharge capacity than the undoped one as increasing current rates. Among the three Zn-doped samples, Li3V1.96Zn0.04(PO4)3/C shows the highest initial discharge capacity of 105.5 mAh g−1 at 5C. Capacity retention for Li3V1.96Zn0.04(PO4)3/C remains 83.6% at 0.2C after 50 cycles, higher than 62.8% for Li3V2(PO4)3/C. It is believed that Zn substitution is beneficial to the rate performance and cyclic performance due to the lower charge transfer resistance and higher diffusion coefficient of lithium ions resulted from relatively higher intrinsic conductivity and smaller particle size.
The electrochemical performance of LiFePO4 in lithium cells is strongly dependent on the structure (disordered/graphene or D/G ratio) of the in situ carbon produced during synthesis from carbon-containing precursors. Addition of pyromellitic acid (PA) prior to final calcination results in lower D/G ratios, yielding a higher-rate material. Further, improvements in electrochemical performance are realized when graphitization catalysts such as ferrocene are also added during LiFePO4 preparation, although overall carbon content is still less than 2wt.%.
Hierarchically porous Co3O4 film is prepared via a hydrothermal synthesis method based on a self-assembled monolayer polystyrene (PS) spheres template. The as-prepared Co3O4 film shows a two-layer structure: substructure is composed of Co3O4 monolayer hollow-sphere array and the superstructure consists of porous net-like Co3O4 nanoflakes possessing continuous mesopores ranging from 2 to 5nm. The pseudocapacitive behavior of the hierarchically porous Co3O4 film is investigated by cyclic voltammograms (CV) and galvanostatic charge–discharge tests in 2M KOH. As cathode material for supercapacitors, the hierarchically porous Co3O4 film exhibits noticeable pseudocapacitive properties with a capacitance of 454Fg−1 at 2Ag−1 as well as quite good cycling stability and high capacitance retention. Compared to the film prepared without template, the hierarchically porous film exhibits weaker polarization, higher capacitances and better cycling performance. The enhancement of pseudocapacitive properties are due to the hierarchically porous architecture, which provides fast ion/electron transfer and alleviates the structure degradation caused by volume expansion during the cycling process.
This paper investigates the influence of elastic stresses and surface patterns on electrodic reaction rates. There are several well known processes that affect electrodic reaction rates such as rupture of passive layers, repassivation, and hydrogen adsoption, among others. Our main goal in this paper is to isolate the direct influence of elastic stresses and surface patterns on reaction rates. To this end, we propose an extended Butler–Volmer equation that incorporates the effect of stress and surface curvature on the chemical potential. The proposed extension of the Butler–Volmer equation is sensitive to both the magnitude and the tensile or compressive nature of the stress field. Our numerical studies show that, depending on the electrodic material, stress and surface curvature can produce a significant shift of the chemical potential, and hence, amplify or reduce electrodic reaction rates. We verified the shift in reaction rates predicted by our proposed continuum model using ab-initio electronic structure calculations. As an application of our proposed model, we demonstrate how a stress field in an electrodic domain may significantly affect the evolution of an anodic dissolution front.
Electrical energy storage is expected to be important for decarbonizing personal transport and enabling highly renewable electricity systems. This study analyses data on 11 storage technologies, constructing experience curves to project future prices, and explores feasible timelines for their economic competitiveness.
The properties of graphite/Li[(Ni0.5Mn0.5) x Co y (Li1/3Mn2/3)1/3]O2 (x + y =2/3, y =1/12 and 1/6) Li-ion cells are reported. There is an extended plateau near 4.5V during the first charging of the cells that corresponds to the simultaneous removal of Li and oxygen from the Li[(Ni0.5Mn0.5) x Co y (Li1/3Mn2/3)1/3]O2 (x + y =2/3, y =1/12 and 1/6) electrodes. The release of this oxygen directly within a Li-ion cell has been a cause for concern. However, it was found that subsequent to O2 release, Li-ion cells delivered a high reversible positive electrode specific capacity near 250mAh/g at C/30 between 2.5 and 4.8V, the cells did not display increased irreversible capacity relative to counterparts having Li metal negative electrodes and the cells retained 85% of their initial capacity after 70 cycles at C/6 between 2.5 and 4.6V. Therefore, the O2 released during the first charge does not significantly impact the electrochemical properties of graphite/Li[(Ni0.5Mn0.5) x Co y (Li1/3Mn2/3)1/3]O2 (x + y =2/3) lithium-ion cells.
LiNi1/3Co1/3Mn1/3O2 particles were coated with Al2O3 nanoparticles by means of a mechanochemical bonding process; SEM confirmed that the Al2O3 particles were uniformly coated over the surface of the LiNi1/3Co1/3Mn1/3O2 powder. During subsequent electrochemical testing using pouch cells, uncoated LiNi1/3Co1/3Mn1/3O2 exhibited a gradual capacity fading and an increase in area specific impedance (ASI) at a 50% state of charge. Under the same conditions, the increase in ASI of the Al2O3 modified samples was significantly suppressed, although the initial performance (charge/discharge capacity and ASI) slightly deteriorated. The Al2O3 coating was also effective in improving the cyclability of LiNi1/3Co1/3Mn1/3O2 at elevated temperatures by reducing the extent of cracking.
In this work, polycarbonate composite membranes were prepared for proton exchange membrane fuel cells (PEMFCs). In the preparation of membranes, a small amount of poly(ethylene glycol) (PEG) was blended with polycarbonate (PC) solution and then cast to make membranes. PEG contained in the membrane was removed by the high solubility of supercritical CO2 to afford porosity in the membrane. Then, porous PC membranes were soaked in Nafion® solution to yield the PC/Nafion® composite membranes. The PC composite membrane had lower ion conductivity but higher conductance than Nafion®.
In the April 2003 issue of Membrane Technology we published a feature entitled ‘Membranes set to play important role in hydrogen economy’, which identified the way in which such materials may be used in a so-called ‘hydrogen economy’, by considering recent developments in technologies that are being used to generate and store hydrogen. The brief feature here looks at potential membrane-based technologies which have been developed to produce energy from waste.
Unknown Note: Page numbers with “f” denote figures; “t” tables and “b” boxes.
Piped streams, or streams that run underground, are often associated with urbanization. Despite the fact that they are ubiquitous in many urban watersheds, there is little empirical evidence regarding the ecological structure and function of piped stream reaches. This study measured ecosystem metabolism, nutrient uptake, and related characteristics of Pettee Brook—an urban stream that flows through several piped sections in Durham, New Hampshire, USA. Pettee Brook had high chloride and nutrient concentrations, low benthic biomass, and low rates of gross primary productivity (GPP), ecosystem respiration (ER), and nutrient uptake along its entire length during summer. Spring was a period of elevated biological activity, as increased light availability in the un-piped sections of the stream led to substantially higher GPP, ER, NH4 uptake, and PO4 uptake in these open reaches. Piped reaches of Pettee Brook were similar to open reaches in terms of water quality, dissolved O2 concentration, temperature, and discharge. Piped reaches did, however, have significantly less light, shallower sediments, and no debris dams. The absence of light inhibited autotrophic activity in piped reaches, resulting in the complete loss of GPP as well as a significant reduction in benthic AFDM and chlorophyll a biomass. Heterotrophic activity in piped reaches was not impaired to the same extent as autotrophic activity. Reduced ER was observed in piped reaches during the summer, but we failed to find significantly lower DOC or nutrient uptake rates in piped reaches than in open reaches. Carbon consumption in piped reaches, which do not have significant autochthonous or allochthonous carbon replenishment, must rely primarily on upstream inputs of organic matter. These results suggest that although ecological conditions in piped streams may be degraded beyond the extent of other urban stream reaches, piped reaches may still sustain some measurable ecosystem function.
Auditory word comprehension was assessed in a series of 289 acute left hemisphere stroke patients. Participants decided whether an auditorily presented word matched a picture. On different trials, words were presented with a matching picture, a semantic foil, or a phonemic foil. Participants had significantly more trouble with semantic foils across all levels of impairment.
The 0.6Li2MnO3–0.4Li(Co1/3Ni1/3Mn1/3)O2 solid solution was prepared by the co-precipitation method. The average structure analysis based on the Rietveld method using neutron diffraction was carried out. As a result, the charging process eliminated Li from the transition metal layer as well as the lithium layer, and the dominant elimination of Li was suggested to be from the 2b site (S.G.; C2/m). The amount of the cation mixing of Ni at the 2c site in the Li layer tended to increase from the first to fifth cycles. It was suggested that Co moved to the 4g site after discharge, but to the 2b site after charging. On the other hand, the opposite tendency was shown for Mn. In addition, an electronic-structure analysis based on the Maximum Entropy Method was carried out. The covalent linkage increased in 4h-4i and 4h-8j between the first and fifth charge processes. It was also found that most of the Li in the 4h site was not extracted at the fifth cycle compared to the first cycle.
Background The dimensionality of premorbid adjustment (PA) has been a debated issue, with attempts to determine whether PA is a unitary construct or composed of several independent domains characterized by a differential deterioration pattern and specific outcome correlates. Aims This study examines the factorial structure of PA, as well as, the course and correlates of its domains. Method Retrospective study of 84 adult patients experiencing first-episode psychosis (FEP) (n=33) and individuals with schizophrenia (SCH) (n=51). All patients were evaluated with a comprehensive battery of instruments including clinical, functioning and neuropsychological variables. A principal component analysis accompanied by a varimax rotation method was used to examine the factor structure of the PAS-S scale. Paired t tests and Wilcoxon rank tests were used to assess the changes in PAS domains over time. Bivariate correlation analyses were performed to analyse the relationship between PAS factors and clinical, social and cognitive variables. Results PA was better explained by three factors (71.65% of the variance): Academic PA, Social PA and Socio-sexual PA. The academic domain showed higher scores of PA from childhood. Social and clinical variables were more strongly related to Social PA and Socio-sexual PA domains, and the Academic PA domain was exclusively associated with cognitive variables. Conclusion This study supports previous evidence, emphasizing the validity of dividing PA into its sub-components. A differential deterioration pattern and specific correlates were observed in each PA domains, suggesting that impairments in each PA domain might predispose individuals to develop different expressions of psychotic dimensions.