batterydata/paper-abstracts huggingface dataset:
The effects of three well-known electrolyte additives, used singly or in combination, on LiCoO2/graphite pouch cells has been investigated using the ultra high precision charger (UHPC) at Dalhousie University, electrochemical impedance spectroscopy (EIS) and long term cycling Vinylene carbonate (VC), vinyl ethylene carbonate (VEC), and lithium bis(oxalato) borate (LiBOB) were chosen for study. The results show that combinations of electrolyte additives that act synergistically can be more effective than a single electrolyte additive. However, simply using 2% VC yielded cells very competitive in coulombic efficiency (CE), charge endpoint capacity slippage and charge transfer resistance (R ct). For cells with 1% LiBOB and VC (1, 2, 4 or 6%), adding VC above 2% does not increase the CE, but increases the electrode charge transfer impedances. R ct for cells containing 1% LiBOB and VEC (0.5, 1 or 4%) decreased after long term cycling (1800 h), compared to that tested after the UHPC cycling (500 h) indicating that VEC might be useful for the design of power cells. However, the opposite behaviour (increasing R ct with cycle number) was observed for the control cells or cells containing LiBOB and/or VC.
This article provides a perspective on solid oxide fuel cells operating at low temperature, defined here to be the range from ∼400 °C to 650 °C. These low-temperature solid oxide fuel cells (LT-SOFCs) have seen considerable research and development and are widely viewed as the “next generation” technology, following the 650–850 °C SOFCs that are currently undergoing commercialization. LT-SOFCs have potential advantages for conventional SOFC applications such as stationary power generation, and may be viable for new portable and transportation power applications, along with electrolytic fuel production and energy storage. The characteristics of electrolyte and electrode materials are reviewed, with a focus on materials that have demonstrated good properties and cell performance at low temperature. Only oxygen-ion-conducting electrolytes are considered here. Anode materials are discussed, primarily the various Ni–cermet anode compositions that yield good low-temperature performance. Mixed ionically and electronically conducting cathode materials are described in detail, reflecting the extensive research activity that has aimed at providing useful oxygen reduction kinetics at low operating temperature. Cell design, materials compatibility, processing methods, and resulting microstructures are discussed, along with their role in determining cell performance. Results from state of the art LT-SOFCs are presented, and future prospects are discussed.
Nano-crystalline metal oxides (Co3O4, CuO, and NiO) are synthesized as anode materials for lithium-ion batteries by an ultrasonic spray pyrolysis method. The effects of calcination temperature on the morphology, crystallite size and electrochemical properties of the metal oxides are investigated. X-ray diffraction (XRD) studies show that the crystallite size varies with the final calcination temperature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations reveal that the calcination temperature strongly influences the morphology of the prepared metal oxides and this results in different electrochemical performance. The existence of a nano-scale microstructure for the prepared metal oxides has a strong relationship with irreversible capacity and capacity retention.
In this study, we present two approaches to developing composite electrolytes exploiting the self-assembling nature of colloidal fillers. The first system comprises of oligomers of poly(ethylene glycol) dimethyl ether, branched fumed silica particulates and lithium salt. The fumed silica forms a three-dimensional, self-supporting network that provides mechanical stability. The large pores of the network has little effect on diffusivity of ions and oligomers, lithium transference number and ionic conductivity, with the latter showing values >10−3 S/cm at ambient conditions. The second system consists of Li exchanged hectorite clay in a mixture of low molar mass carbonates. Similar to the fumed silica, the clay provides mechanical stability through formation of a three-dimensional network. In addition, the immobile clay platelets also serve as the anion rendering the system to be a single ion conductor. Near-unity transference number is observed in this case. However, the room temperature conductivity of the clay composite is lower than the fumed silica, revealing a value of about 10−4 S/cm. The lower conductivity can be attributed to the clay not being in a fully exfoliated form as evident from morphological analysis.
The 1st EuNetAir Air Quality Joint Intercomparison Exercise organized in Aveiro (Portugal) from 13th–27th October 2014, focused on the evaluation and assessment of environmental gas, particulate matter (PM) and meteorological microsensors, versus standard air quality reference methods through an experimental urban air quality monitoring campaign. The IDAD-Institute of Environment and Development Air Quality Mobile Laboratory was placed at an urban traffic location in the city centre of Aveiro to conduct continuous measurements with standard equipment and reference analysers for CO, NOx, O3, SO2, PM10, PM2.5, temperature, humidity, wind speed and direction, solar radiation and precipitation. The comparison of the sensor data generated by different microsensor-systems installed side-by-side with reference analysers, contributes to the assessment of the performance and the accuracy of microsensor-systems in a real-world context, and supports their calibration and further development. The overall performance of the sensors in terms of their statistical metrics and measurement profile indicates significant differences in the results depending on the platform and on the sensors considered. In terms of pollutants, some promising results were observed for O3 (r2: 0.12–0.77), CO (r2: 0.53–0.87), and NO2 (r2: 0.02–0.89). For PM (r2: 0.07–0.36) and SO2 (r2: 0.09–0.20) the results show a poor performance with low correlation coefficients between the reference and microsensor measurements. These field observations under specific environmental conditions suggest that the relevant microsensor platforms, if supported by the proper post processing and data modelling tools, have enormous potential for new strategies in air quality control.
The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD). Twenty three AD patients and age-matched controls named pictures of objects and actions and took part in a word-picture verification task. The results for picture naming revealed that both patients and controls were faster and produced more target responses for objects than actions. In the comprehension task, accuracy levels were comparable for nouns and verbs, but response times were longer for verbs. Although patients were more error prone and had longer latencies in both tasks than controls, the only qualitative difference in performance between the groups was in response to trials with semantically related foils in the word-picture verification task. Patients were particularly error prone in this condition. We conclude that the results do not provide support for the notion that verbs are selectively preserved in AD. They also do not provide conclusive evidence for claims that depressed naming and comprehension is (always) due to loss of semantic knowledge or inadequate access to semantic knowledge. Finally, we discuss the findings in relation to comparable investigations in patients with semantic dementia.
Cranial radiation therapy (CRT) for treatment of brain tumours in paediatric patients can cause subsequent neurocognitive impairment, particularly in patients who were very young at the time of irradiationCRT can impair development of white and grey matter, and can inhibit neurogenesis and synaptic plasticity—two processes that are crucial for learning and academic achievementAdditional factors, such as the tumour itself, hydrocephalus, chemotherapy and other drugs, can contribute to cognitive impairment in survivors of paediatric brain tumoursNew strategies to prevent and treat CRT-induced neurocognitive damage, most notably new radiation techniques that spare healthy brain tissue, are increasingly used to avoid this adverse effect of radiotherapyRehabilitation of paediatric patients treated with CRT is also possible through the child's school environment and cognitive training programmes
CNS malignancies, which represent 30% of childhood tumours, is a term that encompasses a heterogeneous range of diseases. Their treatment is complex and usually combines surgery, chemotherapy and/or targeted therapies, and cranial radiation therapy (CRT).1 Over the past decade, dramatic improvements have been made in the management of paediatric brain tumours, resulting in improved patient survival.1 Medulloblastoma and low-grade glioma are the two most common childhood brain tumours, with a progression-free survival rate of 60–85%.
The surface natures of five carbon materials, acetylene black, Super P, ECP600JD, KS-6 and CNTs, are compared in terms of morphology, specific surface area and activity towards electrolyte decomposition and anion insertion, and their contributions as conductive additives to cathode performance of lithium ion batteries are understood. With the characterizations from scanning electron microscopy, Brunauer–Emmett–Teller analysis and cyclic voltammetry, it's demonstrated that: (1) the morphology is granular for acetylene black, Super P and ECP600JD, flake-like for KS-6 and wire-like for CNTs; (2) ECP600JD exhibits the largest specific surface area but KS-6 has the smallest one; (3) the activity is the same for all the samples towards the electrolyte decomposition but different from each other towards anion insertion. Charge/discharge tests of LiMn2O4 and LiNi0.5Mn1.5O4 cathodes indicate that the surface natures of carbon materials play an important role in charge/discharge performance of cathodes for lithium ion batteries. ECP600JD with smallest particle size provides the largest site for electrolyte decomposition leading to the lowest coulombic efficiency, while KS-6 with a layered structure exhibits the highest activity towards anion insertion leading to the lowest charge and discharge capacity of cathode materials. These negative effects become more significant when high voltage cathode materials are used.
The Air Force Research Laboratory is developing lithium-ion batteries for low earth orbit (LEO) and geosynchronous earth orbit (GEO) spacecraft applications. As a part of this lithium-ion battery development effort, a testing program is underway to determine the viability of lithium-ion batteries for LEO/GEO applications. For LEO, lithium-ion battery cycle lifetimes of >60,000 cycles at 25% depth-of-discharge (DOD) are projected. For GEO, lifetimes of >14 years at 80% depth-of-discharge are projected.
The effects of depositing ultrathin (<1 nm) Al2O3 coatings on LiNi0.5Mn1.5O4 (LNMO) particles using atomic layer deposition (ALD) are presented. Promising electrochemical performance of the Al2O3 ALD coated LNMO at 30 °C is demonstrated in not only significantly improved coulombic efficiency, cycle retention, and rate capability, but also in dramatically suppressed self-discharge and dissolution of transition metals. Combined analyses by electrochemical impedance spectroscopy, ex-situ X-ray photoelectron spectroscopy, and ex-situ time-of-flight secondary ion mass spectrometry reveal that the solid electrolyte interphase layer on the Al2O3 ALD coated LNMO is much thinner and contains fewer organic species than the one on the bare LNMO. This difference originates from the suppression of the side reaction at high voltage by the Al2O3 ALD protective coating. Also, fluorination of Al2O3 ALD layer upon repeated charge–discharge cycling is confirmed, and this can account for the capacity increases during the initial charge–discharge cycles. Finally, it is also demonstrated that a full LNMO/Li4Ti5O12 battery incorporating the Al2O3 ALD coated LNMO outperforms the one incorporating only bare LNMO.
We simulate a simple model of aging in a lithium-ion cell that accounts for growth of a passivation film on the negative electrode, on top of an electrochemical-thermal pseudo-two-dimensional (P2D) description of “ideal” (i.e., ignoring aging effects) cell dynamics, using a finite-volume Matlab code. Capacity fade is assessed by evaluating at each instant in time the loss of cyclable lithium ions, which follows as a consequence of a single irreversible electrolyte decomposition reaction in the aging model. Assuming reasonable values for the side reaction rate and SEI film conductivity, we show an estimated 2.5% capacity loss after 1600 cycles at 1C. We also find a growth rate of about 0.64 nm/hr at 1C for the SEI film on the negative electrode, in a linear growth regime obtained by neglecting any diffusive transport limitations during new SEI formation. In addition, we show that for an “ideal” cell under cyclic loading conditions its energy dissipation (per cycle) is constant as a function of cycle number, while that same quantity keeps increasing with cycle number for an aging cell. Finally, we discuss the influence of the aging model as it affects surface cell temperature as a function of a (convective) heat transfer coefficient. Specifically, for values of h larger than about 1 W/(m2 K) we find essentially no effect of the aging model on surface cell temperature, which remains equal for all time to the surrounding ambient temperature. For smaller values of h, however, we find surface cell temperatures that are systematically larger than their “ideal” cell counterparts, with a strictly monotonic (increasing) behavior of the steady-state surface cell temperature as a function of the (reciprocal) heat transfer coefficient.
The major problems of polymer electrolyte membrane fuel cell technology that need to be highlighted are fuel crossovers (e.g., methanol or hydrogen leaking across fuel cell membranes), CO poisoning, low durability, and high cost. Chitosan and alginate-based biopolymer membranes have recently been used to solve these problems with promising results. Current research in biopolymer membrane materials and systems has focused on the following: 1) the development of novel and efficient biopolymer materials; and 2) increasing the processing capacity of membrane operations. Consequently, chitosan and alginate-based biopolymers seek to enhance fuel cell performance by improving proton conductivity, membrane durability, and reducing fuel crossover and electro-osmotic drag. There are four groups of chitosan-based membranes (categorized according to their reaction and preparation): self-cross-linked and salt-complexed chitosans, chitosan-based polymer blends, chitosan/inorganic filler composites, and chitosan/polymer composites. There are only three alginate-based membranes that have been synthesized for fuel cell application. This work aims to review the state-of-the-art in the growth of chitosan and alginate-based biopolymer membranes for fuel cell applications.
Accurate and efficient monitoring of electrical machine (EM) operating parameters, including temperature, mechanical vibration, torque and rotating speed and others that can indicate the EM health conditions is becoming ever more important in the world of electrical drives. The traditional methodology of one sensor per parameter can be theoretically replaced by a “one sensor measures all” technology, which can be achieved through the use of fibre-optic sensors (FOS). In this paper, several FOSs, which use different optical sensing principles for multiple physical parameter measurements of EMs, are reviewed. This paper also provides an insight into the major developments, and discusses the engineering challenges of FOS used for EM monitoring over the last few decades, and compares the advanced features of FOS with those of conventional sensors in use. Finally, a novel FOS-EM observer system scheme employing the Fibre Bragg Grating technique for multi-parameter monitoring of EM health is proposed, after discussion of the preceding industrial and academic FOS cases for EM applications.
Because of the inevitable inconsistency during manufacture and use of battery cells, cell variations in battery packs have significant impacts on battery pack capacities, durability and safety for electric vehicles (EVs). To reduce cell variations and increase pack capacity, cell equalization is essentially required. In the series of two papers, we discover that dissipative cell equalization (DCE) using dissipative resistances is a feasible on-line equalization method for battery packs in EVs. We subsequently propose on-line equalization algorithms for lithium-ion battery packs based on charging cell voltage curves (CCVCs). The objective of these algorithms is to maximize pack capacities by conditioning CCVCs. As the first paper of the series, we first briefly review equalization topologies and algorithms. We discover cell remaining charging capacity (RCC) can be on-line estimated and further propose DCE algorithm based on remaining charging capacity estimation (RCCE). We establish a pack model with 8 cells in series and simulate 4 scenes with different cell variations. RCCE–DCE algorithm is proved to be effective by comparing pack capacities with/without RCCE–DCE algorithm. The equalization capability and over-equalization prevention are further examined, and the result shows that RCCE–DCE algorithm is suitable for on-line equalization in EVs.
Designing and manufacturing a novel structural the composite electrode materials can effectively improve the electrochemical performance of lithium ion battery. Hence, in this work, hierarchical nanoflower SnS2 anchored on g-C3N4 nanosheets (the SnS2/CN composite) electrode was creatively synthesized by a facile microwave hydrothermal method. The SnS2/CN composite exhibits excellent cyclic stability, high-rate capacity and structural integrity at higher current density for lithium ion battery. It delivers high discharge capacity of 444.7 mAh·g−1 at a current density of 100 mA g−1 after 100 cycles with the coulombic efficiency of over 99.9%, high specific capacity retention rate at higher current density (383.8 mAh·g−1 and 350.8 mAh·g−1 at the current density of 800 mA g−1 and 1000 mA g−1, respectively). The remarkable electrochemical performances of the SnS2/CN composite electrode are attributed to its large surface area which provides more active sites and accelerates the migration of electrons and lithium ions during charge/discharge cycles. Moreover, the synergistic effect of the g-C3N4 nanosheets and nanoflowers SnS2 electrode shows low charge-transfer resistance, which contributes to the alloying reaction between metallic Sn and lithium ions (Li+) during charge/discharge cycles. Importantly, g-C3N4 nanosheets acting as a spacer can efficiently buffer the volume change and alleviate the collapse or aggregation of SnS2 electrode after repeated cycles.
Microorganisms that can form direct electrical connections with insoluble minerals, electrodes, or other microorganisms can play an important role in some traditional as well as novel bioenergy strategies and can be helpful in the remediation of environmental contamination resulting from the use of more traditional energy sources. The surprising discovery that microorganisms in the genus Geobacter are capable of forming highly conductive networks of filaments that transfer electrons along their length with organic metallic-like conductivity, rather than traditional molecule to molecule electron exchange, provides an explanation for the ability of Geobacter species to grow in subsurface environments with insoluble Fe(III) oxides as the electron acceptor, and effectively remediate groundwater contaminated with hydrocarbon fuels or uranium and similar contaminants associated with the mining and processing of nuclear fuel. A similar organic metallic-like conductivity may be an important mechanism for microorganisms to exchange electrons in syntrophic associations, such as those responsible for the conversion of organic wastes to methane in anaerobic digesters, a proven bioenergy technology. Biofilms with conductivities rivaling those of synthetic polymers help Geobacter species generate the high current densities in microbial fuel cells producing electric current from organic compounds. Electron transfer in the reverse direction, i.e. from electrodes to microbes, is the basis for microbial electrosynthesis, in which microorganisms reduce carbon dioxide to fuels and other useful organic compounds with solar energy in a form of artificial photosynthesis that is more efficient and avoids many of the environmental sustainability concerns associated with biomass-based bioenergy strategies. The ability of Geobacter species to produce highly conductive electronic networks that function in water opens new possibilities in the emerging field of bioelectronics.
Contact dermatitis due to cosmetic products is a common dermatologic complaint that considerably affects the patient's quality of life. Diagnosis, treatment, and preventive strategies represent a substantial cost. This condition accounts for 2% to 4% of all visits to the dermatologist, and approximately 60% of cases are allergic in origin. Most cases are caused by skin hygiene and moisturizing products, followed by cosmetic hair and nail products. Fragrances are the most common cause of allergy to cosmetics, followed by preservatives and hair dyes; however, all components, including natural ingredients, should be considered potential sensitizers. We provide relevant information on the most frequent allergens in cosmetic products, namely, fragrances, preservatives, antioxidants, excipients, surfactants, humectants, emulsifiers, natural ingredients, hair dyes, sunscreens, and nail cosmetics.
Energy drinks are beverages containing vasoactive metabolites, usually a combination of caffeine, taurine, glucuronolactone and sugars. There are concerns about the safety of energy drinks with some countries banning their sales. We determined the acute effects of a popular energy drink, Red Bull, on cardiovascular and hemodynamic variables, cerebrovascular parameters and microvascular endothelial function.
Antitussive drugs are amongst the most widely used medications worldwide; however no new class of drugs have been introduced into the market for many years. Trials showing patient benefit are scarce and have been hampered by the lack of objective and validated outcome measures. Recent improvements in the assessment of cough will facilitate better trials and aid the development of antitussive drugs. When conducting a trial, patient selection is of paramount importance. Patients with unexplained chronic cough and sub-acute cough following upper respiratory tract infection are ideal because they represent an unmet clinical need and an untapped market for pharmaceutical companies. Patients with asthma and chronic obstructive pulmonary disease are less suitable since cough suppression is not always desirable and the findings of trials may not be generalisable to all patients with cough. Randomized, placebo-controlled, double-blind clinical trials are obviously the gold standard. The choice of placebo, whether inert or active, depends on the incidence and severity of drug side-effects. The primary outcome measure should be objective and cough monitors are the ideal tool. Subjective outcome measures should be used to assess symptoms and health related quality of life. Properly conducted clinical trials are an opportunity to evaluate the benefits of currently available therapies and aid advances in the antitussive drug market.