batterydata/paper-abstracts huggingface dataset:
Magnetite is a known lithium intercalation material, and the loss of active, nanocrystalline magnetite can be inferred from the open-circuit potential relaxation. Specifically, for current interruption after relatively small amounts of lithium insertion, the potential first increases and then decreases, and the decrease is hypothesized to be due to a formation of a surface layer, which increases the solid-state lithium concentration in the remaining active material. Comparisons of simulation to experiment suggest that the reactions with the electrolyte result in the formation of a thin layer of electrochemically inactive material, which is best described by a nucleation and growth mechanism. Simulations are consistent with experimental results observed for 6, 8 and 32-nm crystals. Furthermore, simulations capture the experimental differences in lithiation behavior between the first and second cycles.
Understanding the thermal behavior of the solid-electrolyte interphase (SEI) is important for ensuring the overall safety and reliability of Li-ion batteries (LIBs). However, it is difficult to detect intrinsic exothermic heat flows from metastable SEI species during typical thermal characterization because of the high heat capacity of other cell components, such as active materials, binders, and current collectors, in samples. Here, we report a new approach to thermal and chemical characterization of the SEI on LIB anodes. By sampling the separator containing a top part of the SEI from cycled cells (graphite|LiCoO2), and conducting differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, we found that the SEI on the detached separator consisted mainly of metastable organic components, such as polycarbonates and Li alkyl carbonates, which were accumulated over repeated cycles and responsible for large amounts of exothermic signals at low temperatures, as shown in the DSC curves. These findings show that our sampling method enables a detailed thermal analysis on the metastable SEI alone, which can result in self-heating of cells under typical usage conditions.
Polyphenols hold tremendous potential for various electrochemical applications due to their non-covalent bonding-based simple coating process and high compatibility with chelating active metallic species. However, polyphenols are intrinsically prone to full thermal dissociation upon high-temperature carbonization due to the thermal instability of ester linkages in the molecular structure, rarely leaving a residual carbon support for further electrochemical reactions. To overcome this limitation and improve the carbonizability of polyphenol-based complexes, in this report, we employed a planarizing modularization strategy of polyphenols through rearrangement of the molecular structure of tannic acid (TA). During this rearrangement process, TA molecules simultaneously undergo C–C coupling and C–O bonding at each aromatic unit with remarkably enhanced molecular cyclicity to generate modularly interconnected TA (m-TA). The carbonized m-TA provides a high residual carbon content (42% after 900 °C pyrolysis) and maintains the intrinsic graphitic carbonaceous matrix. Furthermore, electrochemically active metallic species (Ni, Co, Fe, or Sn) were readily introduced along with a planarized frame of the carbonized m-TA. As such, the graphitic sp2 domains hybridized with reduced metallic nanoclusters present in carbonized m-TA synergistically imparted outstanding ionic and electrical conductivities. The ideally created new electrochemical platform of graphitically carbonized m-TA was utilized as a highly stable anode for secondary battery systems and as an on-demand electrocatalyst for water splitting with tunable activity.
The V2O5-coated LiNi0.5Mn1.5O4 (LNMO) cathode materials are synthesized via a wet-coating method. V2O5 is capable of lithium intercalating, so the surface of materials is purified. Furthermore lithium ion conductor V2O5 is not only a barrier between electrolyte and LNMO surface to prevent electrolyte decomposition especially at high voltage, but also a HF scavenger thus the spinel structural integrity of LNMO can be preserved for a better cycling reversibility, especially at high temperatures under which conditions the dissolution of Mn3+ ions into electrolyte via reacting with HF is severely problematic for pristine LNMO as cathode materials. The amount of V2O5 coating affects the electrochemical properties of these samples. We discover that the optimal amount of V2O5 on LNMO surface is about 5 wt%. Compared with pristine LNMO, the coating amount with 5 wt% exhibits an excellent rate capability and better reversibility. The discharge capacity is increased by 15.8%, 17.9%, 16.2%, 16.3%, 19.1% and 21.0% in comparison with pure LNMO, presenting a discharge specific capacity of 123.9, 119.1, 120.8, 117.5, 111.9 and 105.3 mAh g−1 at the rates of 0.2, 0.5, 1, 2, 5 and 10C respectively. In addition, the sample presents a discharge capacity of 131.5 mAh g−1 at 1C, with a retention of 92.2% after 100 cycles. Even cycling at 5C rate and 55 °C, the cell with 5% V2O5-coated LNMO cathode can has a capacity of 126.3 mAh g−1, with 92% capacity retention after 100 cycles, implying that V2O5-coating of LNMO is an effective modified method for lithium ion batteries.
Smart construction of advanced anode materials is extremely critical to develop high-performance lithium ion batteries. In this work, we have reported a facile strategy for fabricating Co3O4/polyaniline (PANI) core–shell arrays (CSAs) by chemical bath deposition (CBD) + electrodeposition methods Electrodeposited PANI shell is intimately decorated on the CBD-Co3O4 nanorods forming composite CSAs. Highly conductive network and stress buffer layer are achieved with the aid of tailored PANI shell. Due to these advantages above, the designed Co3O4/PANI CSAS exhibit good electrochemical performance with higher reversible capacity (787mAhg−1) and better cycle stability than the unmodified Co3O4 counterpart. Our results show a new way for preparing advanced inorganic-organic composite electrodes for electrochemical energy storage.
We report the synthesis of pure phase (cubic as well as orthorhombic phase) nanoparticles of Cd2SnO4 (10–15 nm) by a one step solution combustion method and demonstrate their applicability for energy harvesting in photoelectrochemical devices. The criticality of the process parameters in obtaining pure phase nanocrystals is emphasized through the study of the structural, optical and electronic properties. Doctor bladed Cd2SnO4 films, when used as photoanodes for solar water splitting, show a maximum photocurrent of 80 μA cm−2 at 0.5 V for the orthorhombic phase and 250 μA cm−2 at 0.6 V for the cubic phase with respect to an Ag/AgCl reference electrode indicating the good promise of Cd2SnO4 for energy harvesting.
Production of zinc and manganese oxide particles from alkaline and zinc–carbon battery black mass was studied by a pyrolysis process at 850–950°C with various residence times under 1L/minN2(g) flow rate conditions without using any additive. The particular and chemical properties of the battery waste were characterized to investigate the possible reactions and effects on the properties of the reaction products. The thermodynamics of the pyrolysis process were studied using the HSC Chemistry 5.11 software. The carbothermic reduction reaction of battery black mass takes place and makes it possible to produce fine zinc particles by a rapid condensation, after the evaporation of zinc from a pyrolysis batch. The amount of zinc that can be separated from the black mass is increased by both pyrolysis temperature and residence time. Zinc recovery of 97% was achieved at 950°C and 1h residence time using the proposed alkaline battery recycling process. The pyrolysis residue is mainly MnO powder with a low amount of zinc, iron and potassium impurities and has an average particle size of 2.9μm. The obtained zinc particles have an average particle size of about 860nm and consist of hexagonal crystals around 110nm in size. The morphology of the zinc particles changes from a hexagonal shape to s spherical morphology by elevating the pyrolysis temperature.
In this paper we present a three-dimensional computational formulation for electrode-electrolyte-electrode system of Li-Ion batteries. The physical consistency between electrical, thermal and chemical equations is enforced at each time increment by driving the residual of the resulting coupled system of nonlinear equations to zero. The formulation utilizes a rigorous volume averaging approach typical of multiphase formulations used in other fields and recently extended to modeling of supercapacitors [1]. Unlike existing battery modeling methods which use segregated solution of conservation equations and idealized geometries, our unified approach can model arbitrary battery and electrode configurations. The consistency of multi-physics solution also allows for consideration of a wide array of initial conditions and load cases. The formulation accounts for spatio-temporal variations of material and state properties such as electrode/void volume fractions and anisotropic conductivities. The governing differential equations are discretized using the finite element method and solved using a nonlinearly consistent approach that provides robust stability and convergence. The new formulation was validated for standard Li-ion cells and compared against experiments. Its scope and ability to capture spatio-temporal variations of potential and lithium distribution is demonstrated on a prototypical three-dimensional electrode problem.
Solid waste mismanagement in Dhaka, Bangladesh, illustrates a well-known market failure which can be summarized as: waste is a resource in the wrong place. Inorganic materials such as plastic or paper can be used to feed the demand for recycled materials in the industrial sector. Organic materials can be converted and used in the nutrient-starved agricultural sector which is currently heavily depending on chemical fertilizers. They are also a feedstock to generate renewable energy in the form of biogas for this energy-starved country relying on diminishing natural gas reserves and increasing import of coal. Reality however does not capitalize on this potential; instead the waste is a burden for municipal authorities who spend large portions of their budgets attempting to transport it out of the city for discharge into landfills. The major part of these materials still remains uncollected in the residential areas and is discarded indiscriminately in open spaces, polluting the residents’ living environment including water, soil and air resources, in the city and beyond. Bangladeshi authorities have, to some extent, recognized this market failure and have developed policies to encourage the development of waste recycling activities. It is also important to note that this market failure is only partial: a large, mostly informal recycling sector has developed in Bangladesh, focusing on inorganic recyclables of market value. The fact that this sector remains largely informal means that these actors perceive significant barriers to formalization. Comparatively, the organic waste recycling sector is less driven by market mechanisms. Competition from chemical fertilizers and fossil fuels is fierce and hinders the development of market opportunities for compost and renewable energy. Nevertheless commercial production of compost and biogas from organic municipal waste is formalized and benefiting from policy incentives.
Electric vehicles are only as green as the electricity used to charge them, but owners tend to charge vehicles at times of peak use. This study shows that tailored emails increase engagement with information about time-of-use tariffs, with maximal effects within the first three months of ownership.
In this work, by simply heating trisodium citrate dihydrate as sole precursor at 800°C, novel 2D amorphous carbon material (the SC-blank sample) occurs, whose high surface area and large pore volume can reach up to 1015.8m2 g−1 and 2.0cm3 g−1, respectively. Furthermore, we present a synchronous carbonization and graphitization method to produce partially graphitic carbon materials. When heating the mixture of trisodium citrate dihydrate and nickel nitrate hexahydrate as template and graphitization catalyst (the mass ratio of 7:1) at 800°C, the resulting SC-7:1 sample’s surface area has decreased to be 682.8m2 g−1 due to its improved graphitization degree, together with a lower capacity, but a better rate capability. More importantly, in order to further enhance capacity, certain amount of sulfanilic acid azochromotrop (abbr. SAA) serving as redox additive has been introduced into KOH electrolyte. Notably, the SC-blank sample incorporated with SAA redox additive (12mmolL−1) indicates a largely enhanced capacity of 164mAhg−1 when measured at 3Ag−1, which is much larger than that of the pristine one (20mAhg−1). To sum up, the SAA is an efficient redox additive for elevating the capacity.
The intercalation rate of Li+-ions in flake natural graphite with particle size that ranged from 2 to 40μm was investigated. The amount of Li+-ions that intercalate at different rates was determined from measurement of the reversible capacity during deintercalation in 1M LiClO4/1:1 (volume ratio) ethylene carbonate–dimethyl carbonate. The key issues in this study are the role of particle size and fraction of edge sites on the rate of intercalation and deintercalation of Li+-ions. At low specific current (15.5mA/g carbon), the composition of lithiated graphite approaches the theoretical value, x=1 in Li x C6, except for the natural graphite with the largest particle size. However, x decreases with an increase in specific current for all particle sizes. This trend suggests that slow solid-state diffusion of Li+-ions limits the intercalation capacity in graphite. The flake natural graphite with a particle size of 12μm may provide the optimum combination of reversible capacity and irreversible capacity loss in the electrolyte and discharge rates used in this study.
This paper proposes a new battery swapping station (BSS) model to determine the optimized charging scheme for each incoming Electric Vehicle (EV) battery. The objective is to maximize the BSS’s battery stock level and minimize the average charging damage with the use of different types of chargers. An integrated objective function is defined for the multi-objective optimization problem. The genetic algorithm (GA), differential evolution (DE) algorithm and three versions of particle swarm optimization (PSO) algorithms have been implemented to solve the problem, and the results show that GA and DE perform better than the PSO algorithms, but the computational time of GA and DE are longer than using PSO. Hence, the varied population genetic algorithm (VPGA) and varied population differential evolution (VPDE) algorithm are proposed to determine the optimal solution and reduce the computational time of typical evolutionary algorithms. The simulation results show that the performances of the proposed algorithms are comparable with the typical GA and DE, but the computational times of the VPGA and VPDE are significantly shorter. A 24-h simulation study is carried out to examine the feasibility of the model.
In this paper, we will analyze the power requirements of advanced vehicles and assess the likelihood of the top power-source contenders to meet those power requirements in the foreseeable future.
Nanostructured sodium metal orthosilicates hold a lot of promise as next-generation cathodes but their practical application is hindered by the complex crystal structure and electrochemical behaviour. Herein, cubic polymorphs of Na2FeSiO4 with F-43 m symmetry decorated on carbon nanotubes have been synthesised successfully using a novel two-step process. The composite material with 0.08 wt% of carbon nanotubes demonstrate a capacity corresponding to a 1.25 sodium-ion exchange process resulting in 172.9 mAh g−1 at 0.1C cycled in the voltage range between 1.5 and 4.5 V. This work also highlights the mechanism of insertion/extraction process using complementary techniques of X-ray photoelectron spectroscopy, and X-ray diffraction revealing the involvement of Fe 3 d band and conversion of Fe+2 to Fe+3 during first sodium-ion extraction while second sodium-ion extraction is possible due to further oxidation of Fe+3. The discharge capacity is remarkable even at the high current rate of 20C, where we obtained the final capacity of 109.3 mAh g−1. The excellent electrochemical performance reported here is due to the high structural stability of Na2FeSiO4 composed of rigid corner-sharing tetrahedra, improved electronic conductivity by carbon nanotubes, reduced particle size, increased defect structure, high sodium-ion diffusion coefficient and the decreased charge transfer resistances.
The optimal design of the cathode gas diffusion layer (GDL) for direct methanol fuel cells (DMFCs) is not only to attain better cell performance, but also to achieve better water management for the DMFC system. In this work, the effects of both the PTFE loading in the cathode backing layer (BL) as well as in the micro-porous layer (MPL) and the carbon loading in the MPL on both water transport and cell performance were investigated experimentally. The experimental data showed that with the presence of a hydrophobic MPL in the GDL, the water-crossover flux through the membrane decreased slightly with increasing the PTFE loading in the BL. However, a higher PTFE loading in the BL not only lowered cell performance, but also resulted in an unstable discharging process. It was also found that the PTFE loading in the MPL had little effect on the water-crossover flux, but its effect on cell performance was substantial: the 40-wt% PTFE loading in the MPL was found to be the optimal value to achieve the best performance. The experimental results further showed that increasing the carbon loading in the MPL significantly lowered the water-crossover flux, but a too high carbon loading would decrease the cell performance as the result of the increased oxygen transport resistance; the 2.0-mgCcm−2 carbon loading was found to exhibit the best performance.
Background Many patients recovering from a first psychotic episode will discontinue medication against medical advice, even before a 1-year treatment course is completed. Factors associated with treatment adherence in patients with chronic schizophrenia include beliefs about severity of illness and need for treatment, treatment with typical versus atypical antipsychotic and medication side effects. Method In this 2-year prospective study of 254 patients recovering from a first episode of schizophrenia, schizophreniform, or schizoaffective disorder we examined the relationship between antipsychotic medication non-adherence and patient beliefs about: need for treatment, antipsychotic medication benefits, and negative aspects of antipsychotic medication treatment. We also examined the relationship between medication non-adherence and treatment with either haloperidol or olanzapine, and objective measures of symptom response and side effects. Results The likelihood of becoming medication non-adherent for 1 week or longer was greater in subjects whose belief in need for treatment was less (HR=1.75, 95% CI 1.16, 2.65, p =0.0077) or who believed medications were of low benefit (HR=2.88, 95 CI 1.79–4.65, p <0.0001). Subjects randomized to haloperidol were more likely to become medication non-adherent for ≥1 week than subjects randomized to olanzapine (HR-1.51, 95% CI 1.01, 2.27, p =0.045). Conclusion Beliefs about need for treatment and the benefits of antipsychotic medication may be intervention targets to improve likelihood of long-term medication adherence in patients recovering from a first episode of schizophrenia, schizoaffective, or schizophreniform disorder.
Pb1−xSnxF2 layered fluoride super-ionic conductors have become of increased interest for its potential use for all-solid-state secondary fluoride-ion based batteries. By planetary high-energy ball-milling, we have prepared solid-solutions for different stoichiometries: x=0.4–0.6. These materials were investigated by X-ray Diffraction (XRD), Electrochemical Impedance Spectroscopy (EIS), Field Emission Scanning Electron Microscope (FESEM), High-Resolution Transmission Electron Microscope (HRTEM) and Nuclear Magnetic Resonance (NMR) from which a dominant γ-phase (β-PbF2 form) cubic structure with crystal and surface defects have been revealed. Crystallite sizes of around 17nm were achieved. The ionic conductivity of the materials provided a maximum for x=0.45 reaching a value of 2.5·10−3 S·cm−1 at room temperature, with an activation energy of 0.30eV. This solid-state fluorite type electrolyte was applied for testing a solid fluoride ion battery assembly consisting of Bi-cathode and CeF3-anode.
Paediatric GI emergencies constitute a wide range of gut pathologies ranging from those that are common, easily diagnosed and treated to conditions that are rarer, often more severe and challenging to manage. Among a myriad of ordinary clinical symptoms and signs physicians have to identify the child with a serious, life-threatening pathology and initiate the appropriate diagnostic and therapeutic pathway. The aim of the review is to present and discuss a selection of key paediatric GI emergencies that provide challenges in diagnosis and treatment. These conditions are classified by their presentation or pathogenesis and include inflammatory conditions, those presenting with GI obstruction or haemorrhage and the ingestion of foreign bodies or caustic substances. The most recent advances regarding the management of these entities are discussed along with key areas of clinical practice and future research.
As the key component of electrochemical energy storage devices, an electrode with superior ions transport pores is the important premise for high electrochemical performance. In this paper, we developed a unique solution process to prepare freestanding TiO2/graphene hydrogel electrode with tunable density and porous structures. By incorporating room temperature ionic liquids (RTILs), even upon drying, the non-volatile RTILs that remained in the gel film would preserve the efficient ion transport channels and prevent the electrode from closely stacking, to develop dense yet porous structures. As a result, the dense TiO2/graphene gel film as an electrode for lithium ion battery displayed a good gravimetric electrochemical performance and more importantly a high volumetric performance.
3D flower-like NiO hierarchical architectures have been synthesized by a simple ethanolamine (EA)-mediated self-assembly route and subsequent calcination process. The synthesized β-Ni(OH)2 precursors annealed at 300, 400 and 500°C exhibit similar morphology by scanning electron microscopy and different crystallinity, surface area, and pore distribution via X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption/desorption isotherms. The electrochemical properties indicate that the synthesized NiO hierarchical architectures annealed at 300°C show the best electrochemical performance, which presents a reversible specific capacity of 713mAhg−1 at a current density of 100mAg−1 after 40 cycles. With varying the rate from 100 to 1000mAg−1, the capacity still remains 580mAhg−1 at 500mAg−1 after 18 cycles and resumes to 470mAhg−1 at the same rate after 30 cycles. The above results indicate that the 3D flower-like NiO hierarchical architectures are promising anode materials for lithium ion batteries.