batterydata/paper-abstracts huggingface dataset:
Understanding and controlling the growth of the vital Li2O2 product, which is associated with intrinsic property of cathode surface, is essential to design effective cathode catalysts in Li-O2 batteries. Herein we establish the correlation between the Li2O2 growth model and the O2 adsorbability on cathode surface that determines the pathway of the first electron transfer to O2. The weak O2 adsorbability drives the solution growth model to form Li2O2 toroid, while the strong one drives the surface growth model to thin film. Based on this mechanism, we select the N-doped carbon nanocages as cathode to realize a simultaneous large discharge capacity and low charge overpotential by forming copious thin-film Li2O2, deriving from its high specific surface area and enhanced O2 adsorbability due to N-doping. Our study demonstrates an effective strategy to design advanced cathode catalysts in Li–O2 batteries and potentially other metal-air batteries.
The effect of anode material on the performance of microbial fuel cells (MFC), which utilise oxidisable carbon compounds and other components present in sediments on ocean floors, estuaries and other similar environments is reported. The MFC anode materials were carbon sponge, carbon cloth, carbon fibre, and reticulated vitreous carbon (RVC). Power was produced through the microbial activity at the anode in conjunction with, principally, oxygen reduction at a graphite cloth cathode. After a period of stabilisation, open circuit voltages up to 700 mV were observed for most cells. Steady state polarisations gave maximum power densities of 55 mW m−2 using carbon sponge as the anode; which was nearly twice that achieved with carbon cloth. The latter material typically gave power densities of around 20 mW m−2. The performance of the cell was reduced by operation at a low temperature of 5 °C. Generally, for cells which were capable of generating power at current densities of 100 mA m−2 and greater, mass transport was found to limit both the anode and the cathode performance, due primarily to the low concentrations of electro-active species present or generated in cells.
Electric and hybrid vehicles are associated with green technologies and a reduction in greenhouse emissions due to their low emissions of greenhouse gases and fuel-economic benefits over gasoline and diesel vehicles. Recent analyses show nevertheless that electric vehicles contribute to the increase in greenhouse emissions through their excessive need for power sources, particularly in countries with limited availability of renewable energy sources, and result in a net contribution and increase in greenhouse emissions across the European continent. The chemical and electronic components of car batteries and their waste management require also a major investment and development of recycling technologies, to limit the dispersion of electric waste materials in the environment. With an increase in fabrication and consumption of battery technologies and multiplied production of electric vehicles worldwide in recent years, a full review of the cradle-to-grave characteristics of the battery units in electric vehicles and hybrid cars is important. The inherent materials and chemicals for production and the resulting effect on waste-management policies across the European Union are therefore reported here for the scope of updating legislations in context with the rapidly growing sales of electric and hybrid vehicles across the continent. This study provides a cradle-to-grave analysis of the emerging technologies in the transport sector, with an assessment of green chemistries as novel green energy sources for the electric vehicle and microelectronics portable energy landscape. Additionally, this work envisions and surveys the future development of biological systems for energy production, in the view of biobatteries. This work is of critical importance to legislative groups in the European Union for evaluating the life-cycle impact of electric and hybrid vehicle batteries on the environment and for establishing new legislations in context with waste handling of electric and hybrid vehicles and sustain new innovations in the field of sustainable portable energy.
Novel characterization of the thermal properties of batteries have been introduced by defining their frequency-dependent thermal impedance functions. The thermal impedance function can be approximated as a thermal impedance spectrum by analyzing the experimental temperature transient which is related to the thermal impedance function through Laplace transformation. In order to obtain the temperature transient, a process has been devised to generate an external heat pulse with heating wire and to measure the response of the battery. This process is used to study several commercial Li-ion batteries of cylindrical type. Thermal impedance measurements have been performed using a potentiostat/galvanostat controlled by a digital signal processor, which is more commonly available than a flow-meter usually applied for thermal property measurements. Thermal impedance spectra obtained for batteries produced by different manufacturers are found to differ considerably. Comparison of spectra at different states-of-charge indicates an independence of the thermal impedance on the charge state of the battery. It is shown that the thermal impedance spectrum can be used to obtain simultaneously the thermal capacity and the thermal conductivity of the battery by non-linear complex least-squares fit of the spectrum to the thermal impedance model.
A controlled H2SO4-HNO3-CrO3 oxidation strategy has been demonstrated for the synthesis expanded mesocarbon microbeads (EMCMB) with good spherical morphology and high crystal structure. A series of EMCMB with different morphologies and structures were achieved by changing the oxidation time and temperature. The morphologies, structures and electrochemical properties of these samples have been systematically investigated by X-ray diffraction, scanning electron microscope and battery testing system. The results show that the optimal condition is: oxidation temperature is 80°C and oxidation time is 17h. Although the surface crack, the change of spherical degree and graphitization degree of the EMCMB sample is not obvious. When used as an anode in lithium ion batteries, the EMCMB is capable of reaching an extremely high first discharge capacity of 1039.0mAhg−1, while maintaining a good electrochemical stability with a very high capacity of 593.4mAhg−1 after 80 cycles. Relative to GMCMB, the specific capacity of EMCMB is much improved, and the stability is also excellent, indicating that the EMCMB should be a promising electrode material for lithium storage applications.
Functional retrograde amnesia (RA) is a rare pathology and has been rarely studied in detail across different patients. We extensively examined five functional RA patients and compared their neuropsychological profile including anterograde and retrograde memory performance, executive functions, emotional processing, and formally assessed psychiatric symptoms. Across patients, neuropsychological deficits beyond RA were most consistently seen in executive functions and attention suggesting that these dysfunctions contribute to the remote memory deficit. In a majority of the patients, problems in social cognition and emotional behaviour were reflected in Theory of Mind deficits and accompanying psychiatric symptoms. Aberrances in a measure of social desirability were detected, pointing to repressive tendencies in three out of the five patients. Future studies of functional RA patients may investigate more specifically which frontal-lobe associated (dys-) functions contribute to the memory retrieval deficit. Moreover, studying more closely the interaction between social cognition, repressive personality style and memory inhibition in this disease seems worthwhile pursuing.
The plasma cloud mechanism of spoke formation in Saturn's rings, proposed by Goertz and Morfill in 1983, is revisited in the light of new data and the criticisms raised by Farmer and Goldreich [Farmer, A.J., Goldreich, P., 2005. Icarus. This issue]. It is concluded that the plasma cloud model satisfies all available observational and physical constraints.
Practical and accurate state of charge estimation for battery pack is a challenging task due to the inconsistency among in-pack cells. In this paper, we propose a low-complexity state of charge estimation method for series-connected battery pack. Firstly, to reduce computation cost, the capacity and state of charge calculations of battery pack are effectively simplified based on the probability theory. Secondly, we propose a selection method for the representative cells, which is validated by the simulation under Dynamic Stress Test. Subsequently, the state of charge of each representative cell is estimated by the recursive least squares-adaptive extend Kalman filter algorithm successively. Finally, the aging experiments for LiNCM and LiFePO4 battery packs are carried out to validate the feasibility of the simplified method, and the complexity of the three estimation methods is compared. Experimental results indicate that the capacity of battery pack depends only on the representative cells at different cycles, and the proposed “representative cell” method can estimate the state of charge of battery pack with high accuracy and low complexity. The mean absolute errors and root mean square errors for state of charge estimation are less than 3% under Urban Dynamometer Driving Schedule test at different cycles.
The performance of a asymmetric (single-side) pasted positive plate was studied by measuring the current density and potential distributions on both sides of the plate. It was found that the current densities on both sides are almost the same during the early discharge at the 3 C discharge rate. As the discharge proceeds, the current decreases gradually on the non-pasted side and increases on the pasted side. Since more active mass exists on the pasted side, the matrix resistance is higher, causing the polarization to increase by 55–90 mV at the 3 C discharge rate. On the non-pasted side, the active mass undergoes a deeper depth of discharge (DOD). This leads to the shedding of active mass, which shortens the battery life. Since the positive grid on the non-pasted side is exposed, its corrosion rate is faster.
Gel polymer electrolytes (GPEs) are composed of liquid electrolytes in polymer matrices and have been widely used in lithium batteries. The incorporation of fillers in electrolytes has been shown to improve Li+ transport properties due to the interaction of filler materials with the polymer, solvent, or salt. In this work, we report on the preparation of composite GPEs (cGPEs) that contain one-dimensional glass micro-fillers of approximately 1micron in diameter and with an aspect ratio exceeding 100. The cGPEs were electrochemically characterized for Li+ transport properties and were shown to have as high as 37% improvement in ionic conductivity and 25% increase in transference number compared to GPEs, using cGPE with 1% micro-fillers. Li-oxygen batteries containing these cGPEs have also demonstrated superior charge/discharge cycling performance with as a high as 86% more cycles of 500 mAh·g−1 for cGPE-1% batteries compared to GPE batteries. Using electrochemical impedance spectroscopy, this improvement was traced to the stabilization of the interfacial resistances in the batteries owing to the improved Li+ transport properties.
Since the discovery of X-rays over a century ago the techniques applied to the engineering of X-ray sources have remained relatively unchanged. From the inception of thermionic electron sources, which, due to simplicity of fabrication, remain central to almost all X-ray applications, there have been few fundamental technological advances. However, with the emergence of ever more demanding medical and inspection techniques, including computed tomography and tomosynthesis, security inspection, high throughput manufacturing and radiotherapy, has resulted in a considerable level of interest in the development of new fabrication methods. The use of conventional thermionic sources is limited by their slow temporal response and large physical size. In response, field electron emission has emerged as a promising alternative means of deriving a highly controllable electron beam of a well-defined distribution. When coupled to the burgeoning field of nanomaterials, and in particular, carbon nanotubes, such systems present a unique technological opportunity. This review provides a summary of the current state-of-the-art in carbon nanotube-based field emission X-ray sources. We detail the various fabrication techniques and functional advantages associated with their use, including the ability to produce ever smaller electron beam assembles, shaped cathodes, enhanced temporal stability and emergent fast-switching pulsed sources. We conclude with an overview of some of the commercial progress made towards the realisation of an innovative and disruptive technology.
The capacity to identify the unique functional architecture of an individual's brain is a crucial step toward personalized medicine and understanding the neural basis of variation in human cognition and behavior. Here we developed a cortical parcellation approach to accurately map functional organization at the individual level using resting-state functional magnetic resonance imaging (fMRI). A population-based functional atlas and a map of inter-individual variability were employed to guide the iterative search for functional networks in individual subjects. Functional networks mapped by this approach were highly reproducible within subjects and effectively captured the variability across subjects, including individual differences in brain lateralization. The algorithm performed well across different subject populations and data types, including task fMRI data. The approach was then validated by invasive cortical stimulation mapping in surgical patients, suggesting potential for use in clinical applications.
The requirements of high energy density in modern batteries dictate the use of very high (oxidizing) or very low (reducing) potential for negative and positive electrode materials. These extreme potentials can cause molecular compounds to undergo electron transfer reactions at the interfaces. This is well documented for lithium-ion batteries, where a solid electrolyte interphase (SEI) between the lithiated graphite electrode and the electrolyte is formed by the decomposition of electrolyte components mainly during the first charging process. Characterization of the SEI is a challenge because of the variety of chemically similar components and enclosed electrolyte species. Furthermore, ex situ analysis of the SEI requires separation and isolation of the SEI, which may change the content and the structure of the SEI. Scanning electrochemical microscopy (SECM) provides in situ analysis of passivating layers formed at battery electrodes. Such approaches must deal with continuous changes of the studied interfaces. This is illustrated for the in situ investigation of the electron transport at SEI-covered lithiated graphite using 2,5-di-tert-butyl-1,4-dimethoxy benzene as SECM mediator in an inert atmosphere. With this setup, the influence of rinsing protocols on the passivating properties of the SEI was studied. An extensive rinsing compared to our previous studies [DOI 10.1002/anie.201403935] leads to much higher local variation of the SEI passivation properties which continue over the entire observation time of 54h. The second example uses a SECM generation-collection experiment to detect gas permeation through a gas-diffusion electrode (GDE) of a Li-O2 cell into a Li+-containing organic electrolyte. The passivation of the microelectrode was counteracted by pulse amperometric detection allowing to distinguish pore blocking vs. electrode coating by lithium oxides during the discharge. The GDE was positioned between an Ar-O2 and an Ar atmosphere. Imaging of GDE indicated a reduced but not a complete suppression of O2 permeation through the GDE.
The electrochemical properties of Li–O2 batteries are mainly restricted by the kinetics of the OER (oxygen evolution reaction) before realizing high-rate and long-term cycling performance. Among various excellent OER catalysts, RuO2 has shown excellent catalytic activity and good electrical conductivity. Here, a bifunctional catalyst with RuO2 well dispersed on NiCo2O4 nanosheets has been studied, showing a low OER Tafel slope of as low as 58 mV/decade in alkaline media. While assembled in Li–O2 batteries with RuO2 @NiCo2O4 cathode, a large specific discharge capacity as high as 17,633 mAh g−1 can be obtained at a current density of 200 mA g−1 with a coulombic efficiency of 91%. A long-term stability about 128 cycles can be achieved without much deterioration. The excellent electrochemical performance is strongly correlated with the nanosheets like structure for easy O2 diffusion, electrolyte permeation, sufficient space provision of Li2O2 deposition and cooperation of NiCo2O4 and RuO2, which exhibits excellent ORR (oxygen reduction reaction) and OER catalytic activity respectively.
Many childhood cancer survivors develop neurocognitive impairment, negatively affecting education and psychosocial functioning. Recommended comprehensive neuropsychological testing can be time- and cost- intensive for both institutions and patients and their families. It is important to find quick and easily administered surveillance measures to identify those in need of evaluation.
The paper describes the establishment of prior, posterior and predictive distributions for parameters of a normal (Gaussian) electrochemical process with detailed numerical illustrations provided also for the estimation of certain probabilities.
The purpose of this work is to assess the suitability of potential electrolyte additives for zinc morphology control and improved electrochemical performance of the zinc electrode for application in zinc based redox flow battery (RFB) systems. Based on existing literature in the field, sixteen candidates are selected, including four metallic additives, two non-ionic surfactants and ten quaternary ammonium compounds. The electrochemical performance of the zinc electrode is assessed using cyclic voltammetry, linear sweep voltammetry and zinc half-cell cycling tests using chronopotentiometry. Zinc electrodepositions are carried out using chronopotentiometry in order to assess the effect of additives on zinc morphology with scanning electron microscopy. Based on zinc reduction and oxidation reaction potentials, the cycling efficiencies, and the effect on zinc morphology, the most promising additives of those tested are tetraethylammonium hydroxide and tetraethylammonium bromide. Both provide smooth and compact zinc deposits and zinc electrode coulombic efficiencies of 95–97% without leading to significant changes in the zinc reduction/oxidation overpotentials, yielding anodic and cathodic current densities of 77–78 mA cm−2 and 31–32 mA cm−2 at overpotentials of ± 50 mV, respectively. In a zinc-nickel flow cell, these additives provide energy efficiencies of 78–79%, compared with 69% without an additive.
Polyneuropathy presumably lowers quality of life (QoL). However, there is a lack of systematic studies that assess QoL changes and biomarkers of polyneuropathy as determinants of QoL. We aimed to investigate the relationship between every specific aspect of QoL and the clinical parameters used to assess the impairment of motor, sensory (large and small fibers), and autonomic nerves in polyneuropathy.
A series of cobalt oxide/multi-walled carbon nanotube (Co3O4/MWCNT) composites are successfully synthesized by a facile chemical co-precipitation method followed by a simple thermal treatment process. The morphology and structure of as-obtained composites are characterized by X-ray diffraction, scanning electron microscopy, and N2-adsorption/desorption measurements, and the electrochemical properties are investigated by cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). For all Co3O4/MWCNT composites, MWCNTs are well dispersed in the loosely packed Co3O4 nanoparticles. Among them, the Co3O4-5%MWCNT composite exhibits the highest specific surface area of 137m2 g−1 and a mesoporous structure with a narrow distribution of pore size from 2 to 10nm. Because of the synergistic effects coming from Co3O4 nanoparticles and MWCNTs, the electrochemical performances of pure Co3O4 material are significantly improved after adding MWCNTs. The Co3O4-5%MWCNT composite shows the largest specific capacitance of 418Fg−1 at a current density of 0.625Ag−1 in 2M KOH electrolyte. Furthermore, this composite exhibits good cycling stability and lifetime. Therefore, based on the above investigation, such Co3O4/MWCNT composite could be a potential candidate for supercapacitors.
The primary headache disorders, which include migraine, cluster headache and tension-type headache, are among the most common diseases and leading causes of disability worldwide. The available treatment options for primary headache disorders have unsatisfactory rates of efficacy, tolerability and patient adherence. In this Review, we discuss promising new approaches for the prevention of primary headache disorders, such as monoclonal antibodies targeting calcitonin gene-related peptide (CGRP) or its receptor, and small-molecule CGRP receptor antagonists. Neuromodulation approaches employing noninvasive or implantable devices also show promise for treating primary headache disorders. Noninvasive treatments, such as transcranial magnetic stimulation and transcutaneous peripheral nerve stimulation, are delivered by devices that patients can self-administer. Implantable devices targeting the occipital nerves, sphenopalatine ganglion or high cervical spinal cord are placed using percutaneous and/or surgical procedures, and are powered either wirelessly or by surgically implanted batteries. These new and emerging treatments have the potential to address unmet patient needs and reduce headache-associated disability.
Electrochemical reactions in solid oxide fuel cells take place around three-phase boundaries (TPBs). The electrochemically active zones (EAZs) are generated in three-dimensions around the TPBs of on-running SOFCs. This work discusses the behaviours of TPBs and EAZs via a case study on lanthanum strontium vanadate (LSV)–yttria-stabilized zirconia (YSZ) composite anode. A percolating binary particle aggregate, based on geometric random loose packing model and traditional sintering theory, is constructed to represent the LSV–YSZ anode. The TPB lengths of LSV–YSZ anodes are evaluated from the coordination numbers and sintering necks of the particles in the particle aggregate. Empirical interrelations among TPBs, EAZs, active electrode thickness, in-depth penetration of electrocatalysts of polarized LSV–YSZ anode are established.