batterydata/paper-abstracts huggingface dataset:
The objective of this paper is to study the multiobjective optimization problems for the optimal design of lithium-ion batteries. First, a two-objective problem is constructed with the performance measures of energy per unit separator area for the discharge rate of 0.5C and the mass per unit separator area. The reaction zone model and genetic algorithm are employed to solve this problem qualitatively. The resulted Pareto front comes out to be a concave curve in the 2D plane of the two performance measures. Three case studies are guided to illustrate the advantages and applications of employing the multiobjective optimization in the design process. A more sophisticated simulation model is then employed for a three-objective optimization problem with the objectives of energy performance at both low and high discharge rates and mass performance. The problem is quantitatively resolved with the assistance of the electrochemical model and genetic algorithm. The Pareto front comes out to be a curved surface in the 3D space of the three objectives. The properties of the Pareto front are discussed to offer new perspectives on product designs in the industry.
Lithium/water batteries have attracted considerable attention as high power supply devices because they use high energy density lithium metal as an anode and water as a cathode. In this study, we investigate the use of lithium/water batteries that use a glass–ceramics plate as an electrolyte. A lithium ion conducting glass–ceramics plate has no through-holes and does not exhibit moisture permeation. Such a plate has stable ionic conductivity in water. Lithium/water batteries that used a glass–ceramics plate as an electrolyte had a long and stable discharge for 50 days at room temperature when the lithium metal was prevented from coming into contact with water. Lithium/seawater batteries using a glass–ceramics plate as an electrolyte also operated well in the 10–70°C temperature range.
In this work Substrate Induced Coagulation (SIC) was used to coat the cathode material LiCoO2, commonly used in Li-ion batteries, with fine nano-sized particulate titania. Substrate Induced Coagulation is a self-assembled dip-coating process capable of coating different surfaces with fine particulate materials from liquid media. A SIC coating consists of thin and rinse-prove layers of solid particles. An advantage of this dip-coating method is that the method is easy and cheap and that the materials can be handled by standard lab equipment. Here, the SIC coating of titania on LiCoO2 is followed by a solid-state reaction forming new inorganic layers and a core–shell material, while keeping the content of active battery material high. This titania based coating was designed to confine the reaction of extensively delithiated (charged) LiCoO2 and the electrolyte. The core–shell materials were characterized by SEM, XPS, XRD and Rietveld analysis.
Epitaxial LiCoO2 films are synthesized using a sol–gel method. The precursors are aqueous solutions of acetates or nitrates of Li and Co with polyvinylpyrrolidone as a thickener. The LiCoO2 films prepared from the solutions by spin coating are epitaxially grown on sapphire (0001) substrates with c-axis orientation and in-plane alignment of LiCoO2 [ 1 1 ¯ 0 ] ‖sapphire [100]. A two-step heat treatment of the spin-coated films consisting of preheating on a hotplate at the crystallization temperature followed by a high-temperature treatment notably promotes the c-axis orientation. In addition, the crystal orientation is controllable on different planes of the SrTiO3 substrates; the LiCoO2 films are grown with epitaxial relationships of LiCoO2 (001)‖SrTiO3 (111), LiCoO2 (018)‖SrTiO3 (110), and LiCoO2 (104)‖SrTiO3 (100).
Four kinds of ternary phase diagrams of alkali bis(fluorosulfonyl)amides, LiFSA–NaFSA–KFSA, LiFSA–NaFSA–CsFSA, LiFSA–KFSA–CsFSA and NaFSA–KFSA–CsFSA, have been constructed. All the ternary systems possess the only one eutectic point around equimolar composition with the temperature of 309–318K. The electrochemical window of the eutectic LiFSA–KFSA–CsFSA ((x Li, x K, x Cs)=(0.30, 0.35, 0.35)) is as wide as 5.4V at 323K with the cathode limit being lithium metal deposition. The electrochemical window of the eutectic NaFSA–KFSA–CsFSA ((x Na, x K, x Cs)=(0.40, 0.25, 0.35)) is 4.9V at 323K with sodium metal deposition as the cathode limit reaction.
Titanium dioxide (TiO2) and titanate materials such as nanotubes, nanobelts and nanorods were synthesized and their co-catalytic effects were studied by mixing them with Pt/C catalysts. After mixing with these nanomaterials, the methanol oxidation current of Pt/C was increased significantly, but ethanol oxidation current of Pt/C was not increased in acidic medium. Combining with material characterization and electrochemical measurements, the result showed that the co-catalysts with suitable porous channels and higher proton conductivity could accelerate the methanol oxidation, and the co-catalysts containing more adsorbed and structural water could better increase the oxidation of intermediates. TiO2(B) nanobelts and titanate nanotubes are newly developed nanomaterials and protons could transfer along their long-axis. They have showed good co-catalytic effect and would have more applications in direct alcohol fuel cells (DAFC).
Li metal batteries have attracted many attentions owing to their excellent nature, including easier processes and higher energy density than that of conventional Li-ion batteries. However, lithium whiskers often result in the instability of Li anode and electrolyte, and even short circuit, which hinders the safe application of lithium batteries. In this paper, N,N-dimethylethanolamine (DMEA) is employed as a short-chain bifunctional organic additive to save the above problem in Li||LiCoO2 batteries. DMEA not only effectively restrains the growth of Li whiskers by hydroxyl groups and decreases the concentration of free HF by amine groups, but also forms new high ionic-conductivity DMEA-Li based SEI film rather than only hard LiF SEI layer. As a result, the rate performance and capacity of Li||LiCoO2 batteries have been remarkably improved, owing to the participation of bifunctional DMEA. The capacity of 159 mA h g−1 has been retained after 150 cycles with a low capacity fading of 0.07 mA h g−1 per cycle, 43% higher than that of DMEA-free cells at 0.5 C.
The role of triallyl phosphate as an electrolyte additive in Li(Ni0.42Mn0.42Co0.16)O2/graphite pouch cells was studied using ex-situ gas measurements, ultra high precision coulometry, automated storage experiments, electrochemical impedance spectroscopy, long-term cycling and X-ray photoelectron spectroscopy. Cells containing triallyl phosphate produced less gas during formation, cycling and storage than control cells. The use of triallyl phosphate led to higher coulombic efficiency and smaller charge endpoint capacity slippage during ultra high precision charger testing. Cells containing triallyl phosphate showed smaller potential drop during 500 h storage at 40 °C and 60 °C and the voltage drop decreased as the triallyl phosphate content in the electrolyte increased. However, large amounts of triallyl phosphate (>3% by weight in the electrolyte) led to large impedance after cycling and storage. Symmetric cell studies showed large amounts of triallyl phosphate (5% or more) led to significant impedance increase at both negative and positive electrodes. X-ray photoelectron spectroscopy studies suggested that the high impedance came from the polymerization of triallyl phosphate molecules which formed thick solid electrolyte interphase films at the surfaces of both negative and positive electrodes. An optimal amount of 2%–3% triallyl phosphate led to better capacity retention during long term cycling.
Using biochemical, imaging and histological methods, we employed transcriptional targeting to increase the specificity of tumor gene expression in vivo for intravenously administered recombinant adenovirus vectors. Surprisingly, the relative specificity of tumor expression in comparison with other tissues was increased for a constitutively expressing recombinant adenovirus, AdCMVLuc, by simply reducing the viral dose. Even at lower doses, however, the high frequency of viral infection and transgene expression in the liver using constitutive promoters still represents a substantial problem. To further augment tumor specificity, we constructed a series of adenoviruses expressing luciferase from several other promoters and tested their ability to selectively transcribe genes in tumor cells, both in vitro and in vivo. Constitutively active viral promoters (RSV, SRα) varied widely in their tumor selectivity, but hypoxia-responsive promoters (carbonic anhydrase 9, PAI-1, SOD2 and several chimeric constructs) showed the most tumor-selective expression. Our results show that tumor targeting to HT1080 fibrosarcomas was readily achieved using transcriptional targeting mechanisms. We attribute the relatively high level of gene transfer and expression in HT1080 tumors in vivo to increased viral access to the tumor, presumably due to discontinuities in tumor vasculature and augmented expression from stress-responsive promoters in the hypoxic and inflammatory tumor microenvironment.
The understanding of the aging behavior of lithium ion batteries in automotive and energy storage applications is essential for the acceptance of the technology. Therefore, aging experiments were conducted on commercial 18650-type state-of-the-art cells to determine the influence of the temperature during electrochemical cycling on the aging behavior of the different cell components. The cells, based on Li(Ni0.5Co0.2Mn0.3)O2 (NCM532)/graphite, were aged at 20 °C and 45 °C to different states of health. The electrochemical performance of the investigated cells shows remarkable differences depending on the cycling temperature. At contrast to the expected behavior, the cells cycled at 45 °C show a better electrochemical performance over lifetime than the cells cycled at 20 °C. Comprehensive post-mortem analyses revealed the main aging mechanisms, showing a complex interaction between electrodes and electrolyte. The main aging mechanisms of the cells cycled at 45 °C differ strongly at contrast to cells cycled at 20 °C. A strong correlation between the formed SEI, the electrolyte composition and the electrochemical performance over lifetime was observed.
Rechargeable Li-based electrochemical cells are regarded as the most promising candidate for electric vehicle (EV) applications. High-capacity cathode combined with Li anode is a excellent and realizable choice to promote the endurance of rechargeable Li batteries. In this paper, single phase of zirconium pyrovanadate ZrV2O7 was first synthesized via sol-gel method in a low sintering temperature of 500°C. The Li-absent mixed-metal-oxide ZrV2O7, previously regarded as negative thermal expansion (NTE) material only, revealed a high specific capacity of 282.6mAhg−1 and a voltage plateau of 2.48V vs. Li as potential cathode for rechargeable Li batteries. These findings suggest that the ZrV2O7 after further optimization can be employed as high-capacity electrode for rechargeable Li batteries.
Currently, energy development and utilisation are facing two problems in China: the energy crisis and the effects of global warming. An important means to solve the above problems effectively is to increase the intensity of the development and utilisation of photovoltaic system, which directly transforms the inexhaustible solar energy into the powerful green electrical energy. However, some problems plague the development of the photovoltaic industry. Due to these problems, the photovoltaic industry is seriously hindered in its efforts to develop sustainable. Therefore, accurately understanding the developing situation of the photovoltaic industry and analysing and solving the problems that occur during the development process of the photovoltaic industry in China are important topics of current research. This paper presents research results regarding these topics. First, this paper considers the present situation of the photovoltaic industry in China from three aspects: the power market, power generation industry policy and power generation technology level. Second, a discussion of the existing problems of the above three aspects is presented; in addition, based on the developing trends of renewable energy in China, development orientation of the photovoltaic industry are identified for years to come. Finally, strategies are proposed to promote the rapid development of the distributed photovoltaic industry in China.
This paper proposes a hybrid fuel cell powertrain for a powered wheelchair driven by rim motors. Since this innovative wheelchair claims to be light, foldable, and fuel efficient, it would be more promising to have a fuel cell powertrain that is self-charged, extractable, and small in size and weight. The proposed hybrid fuel cell powertrain combines a fuel cell and two secondary battery packs with enough power but minimal in size and weight for the wheelchair. The fuel cell unit is responsible only for charging one of the battery packs, while the other battery by turns supplies power to load. This energy management strategy improves the power fluctuation of the fuel cell as well as reduces the charge frequency of the secondary battery. The effectiveness of the proposed powertrain is evaluated and compared with a traditional hybrid fuel cell powertrain with simulations and experiments, which prove that the output power of the fuel cell is nearly constant and the number of charges is reduced by 98%.
The studies of the composition and structure of comet 67P/Churyumov–Gerasimenko—a short-period comet of Jupiter’s family—which was an object of the recent Rosetta–Philae space mission, yielded results unique in many respects, since it was the first time that a comet was investigated in situ for a long stretch of time under varying conditions of insolation and activity. Due to the landing of the Philae probe, the data on the composition of mineral and organic fractions sampled directly from the cometary nucleus were obtained. Measurements of the coma composition performed with the instruments onboard the Rosetta spacecraft in the early period of observations allowed the data on the composition of its extremally volatile components (N2 and Ar) to be acquired for the first time, while the analysis of the coma composition performed in the postperihelion period provided an adequate insight into the composition of the ice fraction of the cometary nucleus. In the review, along with consolidating the experimental data, we discuss their implications arising in the context of cosmogony and cosmochemistry.
Conversion materials based on metal fluorides offer enhanced charge capacity as positive electrodes in Li-ion electrochemical cells. However, to date, little is understood about the interactions these structurally dynamic materials have with nonaqueous electrolytes during both lithiation and delithiation. Such interactions are explored using bismuth (III) fluoride. This work details the evolution of the electrolyte decomposition products at both highly oxidizing potentials (4.5V vs. Li/Li+) and during delithiation of the positive electrode after having formed a decomposition layer via electrochemical reduction of the electrolyte solvents. For the first time, the impact of the electrolyte reactions on the surface and subsurface chemistry of the inorganic conversion material is explored. Observed results offer an explanation for the direct influence of electrolyte choice on cycling efficiency of metal fluoride conversion materials.
Cognitive Behavioral Social Skills Training (CBSST) is a 24-session weekly group therapy intervention to improve functioning in people with schizophrenia. In our prior randomized clinical trial comparing treatment as usual (TAU) with TAU plus group CBSST (Granholm, E., McQuaid, J.R., McClure, F.S., Auslander, L., Perivoliotis, D., Pedrelli, P., Patterson, T., Jeste, D.V., 2005. A randomized controlled trial of cognitive behavioral social skills training for middle-aged and older outpatients with chronic schizophrenia. Am. J. Psychiatry 162, 520–529.), participants with schizophrenia in CBSST showed significantly better functional outcome than participants in TAU. The present study was a secondary analysis of neuropsychological predictors of functional outcome in our prior CBSST trial. We examined (1) whether neuropsychological impairment at baseline moderated functional outcome in CBSST relative to TAU, and (2) whether improvement in neuropsychological abilities mediated improvement in functional outcome in CBSST. Attention, verbal learning/memory, speed of processing, and executive functions were assessed at baseline, end of treatment, and 12-month follow-up. Greater severity of neuropsychological impairment at baseline predicted poorer functional outcome for both treatment groups (nonspecific predictor), but the interaction between severity of neuropsychological impairment and treatment group was not significant (no moderation). Effect sizes for the difference between treatment groups on functional outcome measures at 12-month follow-up were similar for participants with relatively mild (d =.44–.64) and severe (d =.29–.60) neuropsychological impairment. Results also did not support the hypothesis that improvement in neuropsychological abilities mediated improvement in functioning in CBSST. Adding CBSST to standard pharmacologic care, therefore, improved functioning relative to standard care alone, even for participants with severe neuropsychological impairment, and this improvement in functioning was not related to improvement in neuropsychological abilities in CBSST.
We have realized a Lithium Iron Phosphate (LFP)-graphene nanohybrid obtained by a direct LFP crystal colloidal synthesis on few-layer graphene (FLG) flakes produced by the liquid phase exfoliation (LPE) of pristine graphite. This hybrid material has been tested as a cathode in Li-ion batteries, achieving fast charge/discharge responses to high specific currents. We demonstrate a specific capacity exceeding 110 mAh g−1 at 20 C, with no electrode damaging. Our LFP-FLG electrodes display a low charge transfer resistance, chemical stability and steady electrochemical behavior even under stressful conditions, such as impulsive charges at a high-rate (5 C) and long cycles at 1 C (> 700 cycles). The LFP colloidal synthesis combined with the FLG production by LPE allows for tuning both the LFP-platelets like and FLG flake morphologies in order to promote an optimal connection between the LFP and FLG flakes, ensuring fast charge transfers and consequently high-rate electrochemical performances. The method here proposed yields a scalable production path, which can be easily extended to silicate-, phosphate- and fluorophosphates-based cathode materials for the next generation of high-power lithium batteries.
Spinel Li4Ti5O12 co-doped with Mg2+ and F− was synthesized by solid-state reaction of anatase TiO2, Li2CO3, NH4F, and Mg(NO3)2. For comparison, Mg2+-doped and F−-doped Li4Ti5O12 were prepared using the same method. The structure and electrochemical performance of the prepared materials were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, electrochemical impedance spectroscopy, and galvanostatic charge-discharge tests. Using an internal standard and Rietveld refinement, we calculated the lattice parameters of the samples. After co-doping with Mg2+ and F−, the dopant ions enter the Li4Ti5O12 lattice, resulting in the reduction of Ti4+ to Ti3+, and increasing the conductivity of the material. Furthermore, the Mg2+ and F− co-doping technique resulted in smaller primary particles with a narrow size distribution, factors that can accelerate transfer of Li+ between the electrode and electrolyte. Consequently, the Mg2+ and F− co-doped Li4Ti5O12 material exhibits a superior rate performance and delivers discharge capacities of 159.4, 154.1, 146.5, 120.8, 102.7, and 76mAhg−1 at 0.2C, 0.5C, 1C, 3C, 5C, and 10C, respectively, significantly higher than those of pure Li4Ti5O12 (155.4, 138.6, 124.2, 94.1, 76.7, and 52.2mAhg−1 at the same C-rates). Moreover, the Mg2+ and F− co-doped Li4Ti5O12 showed outstanding cycling stability, and the capacity retention was 99.62% after 150 cycles at 5C rate. Therefore, the Mg2+ and F− co-doping technique has proven an effective approach to improve the electrochemical performance of Li4Ti5O12.
The influence of the addition of polycrystalline Pt, Pd and Ni powders into hydride-forming metal alloy electrodes on the activation process, rate-capability and cycling stability has been evaluated. The metal powder additives were found to improve the activation rate and to decreased the overpotentials of the charge and discharge processes. The electrochemical properties of these modified electrodes were analysed in terms of a simplified form of a previously developed model. Electrochemical impedance spectroscopy measurements were performed to allow the validation of the model and the identification of kinetic and physicochemical parameters.
Absolute pitch (AP) ability is a rare musical phenomenon. In the literature, it has been suggested that the relative specialization for pitch processing is in the right temporal lobe in the non-AP population. Since the anatomic basis for absolute pitch is not fully understood and cases of temporal lobe epilepsy of AP possessors are extremely rare, applicability of resection as a treatment of epilepsy in this particular area should be evaluated with caution. In the present study, we examined an AP possessor who suffered from medically refractory temporal lobe epilepsy and underwent right selective amygdalohippocampectomy (SAH). The SAH procedure clearly avoided disturbing important structures for AP, inasmuch as postsurgically she preserved her AP ability and was seizure-free. She did well post-operatively in the test of pure sine wave tones with short reaction time, which could be identified as “true” absolute pitch.
Effects of 1 M HCl, 0.6 M NaCl with different pH values and 4 M NaOH solutions on the corrosion behaviour of Al–5Zn–1Mg–0.02In–0.05Ti–0.5Mn (wt%) alloy have been investigated using measurements of self-corrosion, potentiodynamic polarization, cyclic polarization experiment combined with open circuit potential technique and scanning electron microscopy. The corrosion behaviour of the alloy was found to be dependant on the Cl−, OH- ions and pH value. In acidic or slightly neutral solutions, general and pitting corrosion occurred simultaneously. In contrast, exposure to alkaline solutions results in general corrosion which was traced back to the dissolution of the resistive oxidation film on the surface of the alloy. Experience revealed that the alloy was susceptible to pitting corrosion in all chloride solution. The alloy undergoes two types of localized corrosion process, leading to the formation of hemispherical and crystallographic pits. Polarization resistance measurements which are in good agreement with those of self-corrosion, show that the corrosion kinetic is minimized in slightly neutral solutions (pH = 7).
Using fiber patch placement, Cevotec is reducing the fiber content, manufacturing time and cost of composite pressure tanks by 20 %. So far, hydrogen tanks designed for a working pressure of up to 700 bar and  1 kg hydrogen storage require about 10 kg of carbon fiber. The solution presented here is still based on wrapping a cylindrical core with continuous fibers. The weak point of established winding processes, however, is that the filament deposition at the domes creates superfluous material. The new solution is to apply carbon fiber patches of the same material to the dome areas prior to the winding process in such a way that they cover exactly those areas that cause problems during winding. In a first process step, the couplings of the tank core are reinforced with patches. The tank cores reinforced in this way are then fed into the shortened winding process, which requires less material and production time to cover the coupling areas. |© Cevotec