batterydata/paper-abstracts huggingface dataset:
The electrolytic insertion of hydrogen into different samples of the intermetallic compound (IMC) TiFe 50/50 was investigated by voltammetry and galvanostatic charging–discharging cycles in order to devise conditions which would lead to extensive hydriding. The voltammetric pattern achieved in aqueous KOH shows both reduction and oxidation peaks well positive to the hydrogen evolution reaction. Such a pattern can hardly be ascribed to facile insertion–extraction of hydrogen since the charge recovered at the anodic peaks after prolonged cathodic reduction of the IMC represents only a few percent of the theoretical charge capacity of the TiFe hydride. Therefore, the detected peaks are attributed primarily to the redox states of surface Fe. In contrast, TiFe hydriding was seen to occur and its extent to increase progressively after repeated charging–discharging cycles carried out in aqueous K2CO3. Although this latter system appears unsuitable for battery applications owing to the large anodic polarization of hydrogen extraction, it nevertheless represents a possible activation route for hydriding TiFe. Faster and more extensive (>100 mA h g−1) hydriding of the IMC was achieved eventually after poisoning the electrolyte with thiourea.
Cylindrical lithium-ion (Li-ion) cells with a nickel-cobalt oxide (LiNi0.73Co0.17Al0.10O2) positive electrode and a non-graphitizable carbon (hard carbon) negative electrode were degraded using cycle tests. The degraded cells were disassembled and examined; most attention was paid to the positive electrodes in order to clarify the origin of the power fade of the cells. X-ray absorption near-edge structure (XANES) analysis demonstrated that the crystal structure of the electrode at the surface changed from rhombohedral to cubic symmetry. Furthermore, a film of lithium carbonate (Li2CO3) covered the surface of the positive electrode after the cycle tests. Using a combination of X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), and glow discharge optical emission spectrometry (GD-OES) measurements, a schematic model of the changes occurring in the surface structure of the positive electrode during the cycle tests was constructed. The appearance of both an electrochemically inactive cubic phase and lithium carbonate films at the surface of the positive electrode are important factors giving rise to power fade of the positive electrode.
The analysis of lithium-ion battery aging relies on correct differentiation between irreversible and reversible capacity changes. Anode overhang regions have been observed to influence Coulombic Efficiency (CE) measurements through lithium diffusion into and out of these areas, complicating precise capacity determination. This work presents an analysis of the extent of graphite anode overhang lithiation after calendar storage by means of local X-ray diffraction (XRD), CE measurements, and color change analysis. We found LiC12 lithiation of the anode overhang area after 20 month storage at 40 °C at high state of charge (SoC) and partial lithiation (LiC18) at medium SoC storage at 40 °C and 25 °C. Graphite color changes in the overhang areas are observed and consistent with the state of lithiation measured by XRD. Coulombic efficiencies greater than unity and increasing capacity during 1200 h of cycling are detected for high SoC storage cells. The capacity difference between high and low storage SoC batteries decreases by up to 40 mAh (3.6% of nominal capacity) after cycling compared to tests directly after storage. Consequently, the size of the anode overhang areas as well as the battery storage temperature and duration need to be considered in CE analysis and state of health assessment.
Herein, double-shelled hollow architecture composed of carbon inner shell and flower-like NiO exterior shell has been prepared through a facile hydrothermal process, followed by a heat treatment. Taking SiO2@RF (resorcinol–formaldehyde resin, RF) sphere as template, the flower-like NiSilicate shell was grown on the surface of RF during the formation of hollow inner structure. The calcination process in the inert atmosphere gives rise to the carbonization and decomposition simultaneously, leading to the formation of carbon-based NiO hollow spheres (C@NiO HSs) with similar structure to that of the parent precursor, which possess large specific surface area (217m2 g−1) and favorable pore structure for supercapacitor application. It is found that C@NiO composite shows higher electrochemical performance than that of pure NiO hollow sphere without interior carbon shell. The C@NiO hollow spheres have high specific capacitance of 211F/g at the current density of 1A/g and good cycle stability (84.6%) after 1000 cycles at the current density of 5A/g, which are superior to NiO HSs without carbon shell. The synthetic strategy can be expanded to fabricate other functional hybrid materials, which should be potential in diverse fields.
Over the past decade, solar photovoltaic (PV) power has experienced dramatic deployment growth coupled with substantial decreases in system prices. This article examines how solar PV power is currently positioned in the electricity marketplace and how that position is likely to evolve in the foreseeable future. We first assess the current cost competitiveness of solar PV in select U.S. locations and industry segments using the levelized cost of electricity (LCOE) metric. This framework enables us to quantify the effects that supportive public policies, time-of-use pricing, and anticipated future technological improvements have on the cost of solar PV. We also build on recent analytical work that has identified circumstances under which it becomes financially attractive to add behind-the-meter batteries to an existing PV solar system. Taken together, our findings suggest that solar power, by itself and in conjunction with low cost storage, is positioned to account for a significant and growing share of the overall energy mix.
Abstract This chapter presents a systematic review of existing literature related with proposed path loss algorithms for data centric critical system protection and data resilience in Wireless Body Area Networks (WBAN) for healthcare framework through elaborating varieties of articles, journal papers, international and national conferences, and theses related with WBAN and proposed algorithms. The chapter delineates exhaustive evaluation of previous research work and methods, their limitations and implementation strategies and developments to provide data resiliency in WBAN area. The chapter also provides a complete literature review on dealing with path loss problem in WBAN area, the current approaches to reduce data loss in medical environments, draw backs associated with the current methods; desire to use cipher algorithm, and theoretical illustration of encryption algorithm. There is much to research about energy saving, this include types of method to decrease path loss, transmission and losses of signals with energy saving battery, useful signal attenuation in energy saving glass and the application of electric sensors node which are also covered within the context of this chapter.
Battery design is a critical aspect of material and system development that leads to the commercialization of effective electrochemical energy storage systems. Successful modeling of battery designs relies upon accurate calculation of the area specific impedance (ASI). A simplified calculation of the ASI is presented that accounts for physical limitations without performing computationally expensive calculations. The limiting currents for transport within the electrolyte and within the intercalation materials are implemented into a linear form of the Butler–Volmer equation to calculate the interfacial impedance. Lithium-ion batteries are then designed to examine the effect of power to energy ratio on battery dimensions. A large ASI is shown to be detrimental to battery design regardless if the increase in impedance results from mass transport limitations or a reduction in electrochemical active area due to small electrode loadings. The smaller electrochemical active area does not increase the voltage losses of a battery when a constant C-rate is maintained. However, the higher ASI values from low electrode loadings require a larger separator and current collector area resulting in a greater battery volume and weight to achieve similar energy and power requirements when compared to a system with a lower ASI.
The influence of pastes from various H2SO4/H2O/PbO ratios on the material structure and electrochemical characteristics of PbO2 electrodes is studied. The structural and electrochemical characteristics of these electrodes are investigated by scanning electron microscopy (SEM), X-ray diffraction, mercury intrusion porosimetry (MIP), ac impedance, and charge–discharge curves. Three pastes (A, B, and C) are studied to assess the influence of H2SO4/H2O/PbO ratios. Paste A, prepared with more water, has a larger specific surface-area and pore-size. The group A plates have a greater porosity, which gives higher active material utilization and higher initial capacity. The plates have poor mechanical strength, however, which results in a high capacity loss for each cycle. In studies on ac impedance, the appearance of a high-frequency inductive loop in the group A plates indicates that these plates have active materials of greater porosity during the electrode processing reactions. The group C plates, prepared with more H2SO4, contained more α-PbO2 crystals which results in a smaller charge-transfer resistance, and a larger exchange current.
Carbon nanotubes (CNTs) became a prominent material for its use in bioanalytical devices due to their biocompatibility, their particular structure, and their conductivity. CNTs have shown to be particularly appropriate to establish electronic communication with redox enzymes since the thin diameter can be approached closely to the redox active sites enabling therefore the regeneration of the biocatalysts either by direct electron transfer (DET) or with the help of so-called redox mediators which serve as intermediated for the electron transfer. The possibility to capture the enzymatic redox processes by obtaining catalytic currents, the use of such CNT-enzyme electrode for biological energy conversion represents the logic consequence. The development of CNT based enzyme biofuel cells (BFCs) is a still young but steadily growing research topic where original approaches to construct electron transfer based CNT-bioelectrodes and impressive biofuel cell performances are highlighted in this review. The evolution of reported biofuel cells consisting of CNTs and enzymes at the bioanode and the biocathode are summarized.
Li[Co1−z Al z ]O2 (0≤ z ≤0.5) samples were prepared by co-precipitation and solid-state methods. The lattice constants varied smoothly with z for the co-precipitated samples but deviated for the solid-state samples above z =0.2. The solid-state method may not produce materials with a uniform cation distribution when the aluminum content is large or when the duration of heating is too brief. Non-stoichiometric Li x [Co0.9Al0.1]O2 samples were synthesized by the co-precipitation method at various nominal compositions x =Li/(Co+Al)=0.95, 1.0, 1.1, 1.2, 1.3. XRD patterns of the Li x [Co0.9Al0.1]O2 samples suggest the solid solution limit is between Li/(Co+Al)=1.1 and 1.2. Electrochemical studies of the Li[Co1−z Al z ]O2 samples were used to measure the rate of capacity reduction with Al content, found to be about −250±30 (mAh/g)/(z =1). Literature work on Li[Ni1/3Mn1/3Co1/3−z Al z ]O2, Li[Ni1−z Al z ]O2 and Li[Mn2−y Al y ]O4 demonstrates the same rate of capacity reduction with Al/(Al+M) ratio. These studies serve as baseline characterization of samples to be used to determine the impact of Al content on the thermal stability of delithiated Li[Co1−z Al z ]O2 in electrolyte.
This paper presents a novel approach based on fuzzy multi-criteria decision-making tools for assessing sustainable alternatives of power generation in San Andrés Island, Colombia. In the first stage, the energy system was established. A fuzzy multi-objective decision approach based on a mixed-integer linear model was implemented to obtain a set of alternatives, including solar photovoltaic, wind turbines, and the diesel plants currently used. Subsequently, the total cost and the CO2 emissions of the energy system were minimized all while considering design, operational, and efficiency constraints. The CO2 emissions and the total present value of the alternatives of energy, together with social, technological, economic, and environmental factors assessed through expert opinions were used as input in the fuzzy multi-criteria decision phase, where a novel fuzzy logic model was employed for selecting the most sustainable alternative. The results indicate that the current diesel capacity in San Andrés Island prevails; with a maximum participation of 3% and 4% of solar and wind systems, respectively.
The role of allyl ethyl carbonate (AEC) as an additive in electrolytes used in lithium-ion batteries is investigated. The 1.0M LiPF6 in propylene carbonate (PC): diethyl carbonate (DEC) (3:2 in volume) electrolyte containing AEC can suppress the co-intercalation of PC and inhibit the decomposition of electrolytes during the first lithium intercalation. A graphitic anode (MCMB-2528, mesocarbon microbeads) in a PC-based electrolyte exhibits a high reversible capacity of 320mAhg−1. The reduction potential of AEC is 1.5V versus Li|Li+ as determined by cyclic voltammetry (CV). The morphology and structure of graphite electrodes after the first charge–discharge cycle are investigated by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). AEC decomposes and forms a proper solid electrolyte interphase (SEI) film on the MCMB surface. The SEI film not only prevents exfoliation of the graphite electrode but also stabilizes the electrolyte. AEC helps to improve the cycleability of lithium-ion batteries to a considerable extent.
Ionic transport inside porous carbon electrodes underpins the storage of energy in supercapacitors and the rate at which they can charge and discharge, yet few studies have elucidated the materials properties that influence ion dynamics. Here we use in situ pulsed field gradient NMR spectroscopy to measure ionic diffusion in supercapacitors directly. We find that confinement in the nanoporous electrode structures decreases the effective self-diffusion coefficients of ions by over two orders of magnitude compared with neat electrolyte, and in-pore diffusion is modulated by changes in ion populations at the electrode/electrolyte interface during charging. Electrolyte concentration and carbon pore size distributions also affect in-pore diffusion and the movement of ions in and out of the nanopores. In light of our findings we propose that controlling the charging mechanism may allow the tuning of the energy and power performances of supercapacitors for a range of different applications.
We report the electrochemical performance of asymmetric hybrid supercapacitors composed of granule Li4Ti5O12 as an anode and activated carbon as a cathode with different current densities. It is demonstrated that the hybrid supercapacitors show good initial discharge capacities were ranged from 39.8 to 46.4 F g−1 in the current densities range of 0.3–1 A g−1. The performance degradation is proportional to the current density due to quick gassing, resulting from H2O and HF formation. In particular, the hybrid supercapacitors show the pretty good cycling stability of 97.4%, even at the high current density of 0.8 A g−1, which are among most important performance in the real application for energy storage devices. Therefore, we believe that hybrid supercapacitors using granule Li4Ti5O12/activated carbon are eligible for the promising next generation energy devices.
A novel energy and cost effective transport chain for stranded natural gas utilized for power production with CO2 capture and storage is developed. It includes an offshore section, a combined gas carrier, and an integrated receiving terminal. In the offshore process, natural gas (NG) is liquefied to LNG by liquid carbon dioxide (LCO2) and liquid inert nitrogen (LIN), which are used as cold carriers. The offshore process is self-supported with power, hot and cold utilities and can operate with little rotating equipment and without flammable refrigerants. In the onshore process, the cryogenic exergy in LNG is used to cool and liquefy the cold carriers, which reduces the power requirement to 319kWh/tonne LNG. Pinch and exergy analyses are used to determine thermodynamically optimized offshore and onshore processes with exergy efficiencies of 87% and 71%, respectively. There are very low emissions from the processes. The estimated specific costs for the offshore and onshore process are 8.0 and 14.6 EUR per tonne LNG, respectively, excluding energy costs. With an electricity price of 100 EUR per MWh, the specific cost of energy in the onshore process is 31.9 EUR per tonne LNG.
Polyethylene (PE)-supported poly(methyl methacrylate-vinyl acetate)-co-poly(ethylene glycol) diacrylate with and without doping nano-Al2O3, namely P(MMA-VAc)-co-PEGDA/PE and P(MMA-VAc)-co-PEGDA/Al2O3/PE, are prepared and their performances as gel polymer electrolytes (GPEs) for lithium ion battery are studied by mechanical test, scanning electron microscopy, thermogravimetric analyzer, electrochemical impedance spectroscopy, cyclic voltammetry, and charge/discharge test. It is found that the doping of nano-Al2O3 in the P(MMA-VAc)-co-PEGDA/PE improves the comprehensive performances of the GPE and thus the rate performance and cyclic stability of the battery. With doping nano-Al2O3, the mechanical and thermal stability of the polymer and the ionic conductivity of the corresponding GPE increases slightly, while the battery exhibits better cyclic stability. The mechanical strength and the decomposition temperature of the polymer increase from 15.9MPa to 16.2MPa and from 410°C to 420°C, respectively. The ionic conductivity of the GPE is from 3.4×10−3 Scm−1 to 3.8×10−3 Scm−1. The discharge capacity of the battery using the GPE with doping nano-Al2O3 keeps 90.9% of its initial capacity after 100 cycles and shows good C-rate performance.
In this paper, we consider the design of a miniaturized proton-exchange membrane (PEM) fuel cell for powering 0.5–20W portable telecommunication and computing devices. Our design is implemented on a silicon substrate to take advantage of advanced silicon processing technology in order to minimize production costs. The reduced length scales afforded by silicon processing allow us to consider designs that would be prohibited by excessive Ohmic losses in larger systems. We employ a mathematical model to quantify the effects of the secondary current distribution on two competing cell designs. In addition to the design of the cell itself, we discuss key integration issues and engineering trade-offs relevant to all miniaturized fuel cell systems: air movement, fuel delivery and water balance, thermal management and load handling.
This study reports on the implementation of protic ionic liquids (PILs) with N‐chloroalkyl functionalized cations and [TFSI]− anion as electrolytes for activated carbon (AC) based electrochemical capacitors (ECs). The electrochemical stability of PILs themselves and risk of corrosive behavior in contact with stainless steel (SSt) and aluminum (Al), as prospective current collectors materials, were investigated. Similar negative stability limits were proven for both materials, yet advantageous passivation of Al under anodic polarization was evidenced. Afterwards, the electrochemical stability was evaluated on porous AC electrodes by potential window opening measurements. For all PILs, it evidenced almost identical performance and stability on AC-electrode under positive polarization owing to the common [TFSI]− anion. Under negative polarization, depending on the electron withdrawing effect of the N-chloroalkyl group on the N-H bond, two types of PIL behavior followed the region of EDL charging: hydrogen chemisorption onto AC or direct electrolyte decomposition. In the former case, the reduction potential of the protonated amine during cathodic sweep, as well as the desorption peak location during the anodic one were proven to be dependent on pKa of the protonated amine. The stability data were used to interpret the voltage limits of symmetric two-electrode cells implementing electrodes made from the same carbon. Finally, the performance of ECs based on the PILs with N-chloroalkyl functionalized cations was determined.
Cells based on NMC/graphite, containing poly(vinylidene difluoride) (PVDF) binders in the positive and negative electrodes, were systematically overcharged to 100, 120, 140, 160, 180, and 250% state-of-charge (SOC). At 250% SOC the cell vented. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) of the anodes showed several state-of-overcharge-dependent trends. Starting at 120% SOC, dendrites appeared and increased in concentration as the SOC increased. Dendrite morphology appeared to be dependent on whether the active material was on the “dull” or “shiny” side of the copper collector. Significantly more delamination of the active material from the collector was seen on the “shiny” side of the collector particularly at 180 and 250% SOC. Transition metals were detected at 120% SOC and increased in concentration as the SOC increased. There was considerable spatial heterogeneity in the microstructures across each laminate with several regions displaying complex layered structures.
This article presents a new method for labeling archaeological material, based on the use of data matrix (DM) codes. The information that identifies an artefact (site name, level or archaeological unit and consecutive number) is coded on very small labels (3×3mm and 4×4mm). This information is captured by a laser reader, which inputs it directly into a computer database. The system has been successfully applied to the pilot study presented here. Its use greatly improves provenance information and management of the archaeological record, and results in the more accurate processing of artefacts in fieldwork routines, laboratory activities and museum storage.
The sharp increase of research passion in the new-generation solar cells in recent years has resulted in a new trend in combining multiple types of energy devices in a single device. In view of the enhanced and/or diversified function of integrated devices, as compared with conventional devices with limited performance or sole applicability, many integrated power packs have been widely developed by combining different devices, such as a silicon solar cell (SSC), Cu(In,Ga)(Sn,Se)2 (CIGS), organic solar cell (OSC), dye-sensitized solar cell (DSSC), perovskite solar cell (PSC), lithium-ion battery (LIB), nanogenerator (NG), supercapacitor (SC), photoelectrosynthetic cell (PESC), and electrolysis cell (ELC), into one unit. In this Review, with a particular emphasis on their recent advances, we cover the integrated solar cell device research in a broad sense and provide an overview of state-of-the-art progress on the integrated solar cell devices based on DSSC and PSC, such as DSSC/LIB, DSSC/SC, DSSC/NG, DSSC/LIB/NG, PSC/OSC, PSC/CIGS, PSC/PSC, PSC/SSC, SSC/SC, PSC/SC, OSC/SC, DSSC/PESC, PSC/PESC, and PSC/ELC, for energy harvesting and storage that are significantly important for self-powering systems and portable/wearable electronics. Finally, the challenges and future outlooks in this promising photovoltaic (PV) field are featured on the basis of current development.