batterydata/paper-abstracts huggingface dataset:
An effective approach to generate nitrogen-doped carbon coating layer on porous silicon (CN@P-Si), one of most promising anode materials for lithium-ion batteries, was addressed in this study to minimize their intrinsic drawbacks of low electrical conductivity and large volume expansion. The resulting enhanced electrochemical performance of the cell using the prepared CN@P-Si materials is attributed to the suppression of volume expansion and formation of the stable solid electrolyte interface by the combination of the porous structure and nitrogen-doped carbon coating layer during the repeated lithiation and delithiation process. After 100 cycles at 0.8Ag−1, the capacity retention is 82% in contrast to 69% for the non-coated samples. Even at the increased discharge current of 20Ag−1, the cell with CN@P-Si electrode delivers a high specific capacity of 1904mAhg−1. After 100 cycles, the P-Si electrode with pores shows huge pulverization; in contrast the CN@P-Si electrode remains intact with reasonably low volume expansion. Nitrogen-doped carbon coating layer on porous Si surface successfully suppress the pulverization of CN@P-Si electrode owing to its shielding capability. These results suggest that CN@P-Si is an attractive candidate for a high-capacity anode for lithium-ion batteries.
A series of fluorine-doped lithium trivanadates LiV3O8−y F z (z =0, 0.03, 0.05, 0.1, 0.15, 0.2 and 0.5) were synthesized by the solid-state reaction. X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscope (SEM) tests show that a proper amount of fluorine substituting for oxygen in LiV3O8 can modify its structure and surface morphology. Charge–discharge tests show that the doped samples with a proper amount of fluorine display good cycling stability, high coulombic efficiency and good rate capability, compared with undoped sample. The cyclic voltammetry (CV), area-specific impedance (ASI) and electrochemical impedance spectroscopy (EIS) tests indicate that the doped samples with a low fluorine content can stabilize the interface between the surface layer of the active particles and the electrolyte after cycling, while a high fluorine content form an unstable interface. The fluorine substitution is a convenient and effective method for improving the electrochemical performances of LiV3O8.
Artificially grown superstructures from small building blocks is an intriguing subject in ‘bottom-up’ molecular science and nanotechnology. Although discrete nanoparticles with different morphologies and physicochemical properties are readily produced, assembly them into higher-order structure amenable to practical applications is still a considerable challenge. This report introduces a stepwise heterogeneous approach for coupling colloidal quantum dots (QDs) synthesis with self-organization to directly generate quantum chains (QCs). By using vulcanized sulfur precursors, QDs are interdigitated into microscale chainlike supracrystals associated with oleylamine and oleic acid as structure directing agents. The cooperative nature of the QD growth and assembly have been extended to fabricate binary (PbS) and ternary metal chalcogenides (CuInS2) QC superstructures over a range of length scales. In addition, enhanced ion and charge transfer performance have been demonstrated which are determined to originate from the minimum interparticle distance and nearly bare nanocrystal surface. The process reported here is general and can be readily extended to the production of many other metal chalcogenide QD superstructures for energy storage applications.
While the management of PV generation is the prime application of residential batteries, they can deliver additional services in order to help systems to become cost-competitive. They can level-out the demand and potentially reduce the cost and emissions of the energy system by reducing demand peaks. In this study, community energy storage (CES) is optimised to perform both PV energy time-shift and demand load shifting (using retail tariffs with varying prices blocks) simultaneously. The optimisation method obtains the techno-economic benefits of CES systems as a function of the size of the community ranging from a single home to a 100-home community in two different scenarios for the United Kingdom: the year 2020 and a hypothetical zero emissions target. It is demonstrated that the levelised cost and levelised value of CES systems reach intermediate values to those achieved when both applications are performed independently. For the optimal performance of a battery system being charged from both local PV plants and the grid, our results suggest that the battery should be sized suitable to ensure it can fully discharge during the peak period.
Tetramethyl ammonium difluoro(oxalato)borate (TMADFOB) dissolved in the mixed solvents of ethylene and propylene carbonates (EC/PC) instead of neat PC have been proposed as the electrolyte solutions for electrochemical capacitors. The ionic conductivity of 1 M TMADFOB-EC/PC electrolyte solutions has been measured. It climbs up monotonously as EC content increases. Accordingly, the power density of electric double-layer capacitors is enhanced with certain EC addition. The optimum EC content for the power of EDLCs is about 30 volume percentage in the mixed EC/PC solvents. This tendency has been testified by impedance study. The electrochemical behavior of activated carbon/graphite capacitors using these electrolyte solutions has also been studied by galvanostatic charge–discharge test and the charge storage mechanism at the graphite positive electrode has been investigated by in situ XRD and ex situ Raman. The effect of EC addition on DFOB− intercalation into graphite has also been addressed at both room and elevated temperatures.
A new cathodal diffusion layer (CDL) that utilizes mesoporous carbons (MCs) is fabricated and evaluated for the passive direct methanol fuel cell (DMFC). Experimental results reveal that the CDL with MCs (MC-CDL) can accelerate oxygen transport and promote the back diffusion of water from cathode to anode, leading to an increasing power density and enhanced discharge stability. The passive DMFC utilizing such an MC-CDL yields a specific energy of ca. 946 Wh kg−1 at 25°C, which is 2.3 times higher than that of the theoretical specific energy of lithium-ion batteries (∼410 Wh kg−1, LiCoO2/graphite).
The search for cleaner environmentally friendly power sources has been one of the hot topics in research over the past few years. Solid oxide fuel cells can be considered a promising option for the production of clean energy and one of the simplest routes to improve the efficiency of these devices is the microstructural engineering of component materials. In this work, an insight is provided into several cost-effective procedures of microstructural control of SOFC materials, ranging from an “eye-scale” down to the micrometre scale. The proposed procedures may be considered general and as such they can be used to optimise various materials for energy and environmentally related areas.
Developing lightweight, flexible, foldable and sustainable power sources with simple transport and storage remains a challenge and an urgent need for the advancement of next-generation wearable electronics. Here, we report a micro-cable power textile for simultaneously harvesting energy from ambient sunshine and mechanical movement. Solar cells fabricated from lightweight polymer fibres into micro cables are then woven via a shuttle-flying process with fibre-based triboelectric nanogenerators to create a smart fabric. A single layer of such fabric is 320 μm thick and can be integrated into various cloths, curtains, tents and so on. This hybrid power textile, fabricated with a size of 4 cm by 5 cm, was demonstrated to charge a 2 mF commercial capacitor up to 2 V in 1 min under ambient sunlight in the presence of mechanical excitation, such as human motion and wind blowing. The textile could continuously power an electronic watch, directly charge a cell phone and drive water splitting reactions.
With the increasing penetration of distributed renewable energy generation and dynamic electricity pricing schemes, applications for residential demand side management are becoming more appealing. In this work, we present an optimal control model for studying the economic and grid interaction benefits of smart charging of electric vehicles (EV), vehicle-to-grid, and space heating load control for residential houses with on-site photovoltaics (PV). A case study is conducted on 1–10 net zero energy houses with detailed empirical data, resulting in 8–33% yearly electricity cost savings per household with various electric vehicle and space heating system combinations. The self-consumption of PV is also significantly increased. Additional benefits through increasing the number of cooperating households are minor and saturate already at around 3–5 households. Permitting electricity transfer between the houses and EV charging stations at workplaces increases self-sufficiency significantly, but it provides limited economic benefit. The additional cost savings from vehicle-to-grid compared to smart charging are minor due to increased battery degradation, despite a significant self-sufficiency increase. If the optimization is conducted without taking the battery degradation cost into account, the added monetary value of vehicle-to-grid can even be negative due to the unmanaged degradation. Neglecting battery degradation completely leads to overestimation of the vehicle-to-grid cost benefit.
A novel method which is based on the hydrothermal reaction was employed to synthesize LiV3O8. First, the mixture solution of LiOH, V2O5, and NH4OH was subjected to the hydrothermal reaction. The hydrothermal treatment yielded a clear, homogeneous solution. The evaporation of this solution led to the formation of a precursor gel. The gel was then heated at different temperatures in the range of 300–600°C. The characterization by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) indicated that LiV3O8 nanorods have been obtained by this novel synthesis method. The electrochemical performance of the LiV3O8 nanorods have been investigated, which indicates that the highest discharge specific capacity of 302mAh/g in the range of 1.8–4.0V was obtained for the sample heated at 300°C, and its capacity remained 278mAh/g after 30 cycles.
We demonstrate a vanadium redox flow battery with a peak power density of 557mWcm−2 at a state of charge of 60%. This power density, the highest reported to date, was obtained with a zero-gap flow field cell architecture and non-wetproofed carbon paper electrodes. The electrodes were comprised of stacked sheets of carbon paper and optimized through systematic variation of the total electrode thickness. We anticipate significant reductions in the ultimate system cost of redox flow battery systems based on this design.
In this paper we report the results of chemical-physical investigation performed on ternary room temperature ionic liquid–lithium salt mixtures as electrolytes for lithium-ion battery systems. The ternary electrolytes were made by mixing N-methyl-N-propyl pyrrolidinium bis(fluorosulfonyl) imide (PYR13FSI) and N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (PYR14TFSI) ionic liquids with lithium hexafluorophosphate (LiPF6) or lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The mixtures were developed based on preliminary results on the cyclability of graphite electrodes in the IL-LiX binary electrolytes. The results clearly show the beneficial synergic effect of the two ionic liquids on the electrochemical properties of the mixtures.
The effect of deposition temperature and film thickness on the electrochemical performance of amorphous-Si thin films deposited on a copper foil is studied. The electrochemical properties show optimum conditions at 200°C deposition, and thinner films exhibit superior electrochemical performance than thicker ones. A film of 200nm Si deposited at 200°C exhibits excellent cycleability with a specific capacity of ∼3000mAhg−1. This is probably due to optimization between the strong adhesion by Si/Cu interdiffusion and the film stress.
The state-of-charge (SOC) is a critical parameter of a Li-ion battery pack. Differences among in-pack cells are inevitable and can change the total capacity of a pack and the remaining available capacity. Because the traditional methods for the estimation of the SOC of a pack did not consider the difference among the cells and the impact of balance control, we developed a new method that accounts for these problems. To accurately estimate the pack SOC, we establish the relationship between the parameters of the pack and those of in-pack cells under different balance control strategies. This paper also studies the two different types of connections of a battery pack: in series and in parallel. Based on the model of the first over-charged cell and that of the first over-discharged cell, the estimation of the SOC of a battery pack is realized by the Unscented Particle Filter (UPF) algorithm. A simulation experiment verified the method for the estimation of the SOC for a battery pack based on actual data and proved that an accurate estimation value can be obtained by the method.
When designing a building energy system based on renewable energy sources, a major challenge is the suitable sizing of its components. In this paper, a simulation tool is presented for determining the optimal sizes of the main components of a stand-alone building energy system which integrates both thermal and electric renewable energy sources. Since the control of this multisource energy system is a non-trivial, multivariable control problem, particular emphasis is placed on the energy management system. A control structure based on model predictive control is proposed, whereas the underlying optimal control problem is formulated as a mixed-integer linear programming problem. The simulation tool developed is successfully applied on the specific case of an alpine lodge. A set of potential configurations, each being optimal with respect to both the net present costs and the global warming potential, is generated by analyzing the system for various component sizes. Out of this set, the decision makers can choose the most cost efficient configuration fulfilling their specifications.
To determine the proximate consequences of the limited breeding distribution of the critically endangered Waved Albatross (Phoebastria irrorata), we present continuous breeding season GPS tracks highlighting differences in behaviour, destinations, and distances travelled between three distinct colonies: two in Galápagos and one closer to the South American continent on Isla de la Plata, where a small number of pairs nest. Accelerometer data paired with GPS locations allowed operational classifications of Waved Albatross behaviour. All birds from Galápagos travelled eastward to the continental shelf and foraged southward along the Peruvian coast. Birds from Isla de la Plata made more and shorter foraging trips and used habitat north of the destinations of Galápagos birds. La Plata birds foraged in areas through which Galápagos birds commuted, and had slower average flight speeds and shorter commutes. Overall, albatrosses from La Plata might operate under a consistently lower return but they also incur lower costs compared to birds from Galápagos, which take fewer trips involving longer time investment. Galápagos birds may be able to forage more effectively based on more abundant or more profitable food patches in those highly productive areas. Foraging destinations of birds from the two Galápagos colonies were similar and overlapped areas that presented localized mortality risk from artisanal fisheries in previous years. This study, performed across the species’ breeding range, reveals the different foraging distribution of La Plata albatrosses and the potential conservation value of this small colony in terms of maintenance of spatial diversity and behavioural plasticity.
Uninhabited electric vehicle typically utilize batteries as an exclusive power source. In order to remedy the limited energy density and thus operation time of the battery-powered unmanned vehicles, fuel based range extenders are often utilized. The operation strategy for the range extender is to maximize the mission endurance therefore it should operate at minimum specific fuel consumption point. Furthermore, the source and load voltage level may differ, hence non-inverting Buck-Boost converter (NBC) is conjoint them while keeping the desire operation point. This paper proposes a fuel cell (FC) based range extender, interfaced to the main power bus by cascade output power regulation strategy for NBC. The NBC is based on unique modulator that produces switching sequence for both converter legs. The modulator receive single control input from the dual loop regulator, inner inductor current loop and outer output power loop, which is common for energy management strategies of hybrid energy sources. System design commences with regulator design based on small signal analysis of NBC, and then it is shown that the suggested control architecture allows tight output power control throughout the entire operating range despite various plants. Finally a case study is presented, in which the converter operates as power processing interface of a fuel cell, operating as range extender in an all-electrical aircraft. The revealed findings are well-supported by simulation and experimental results.
The morphology of a robot determines how efficiently it can traverse different terrain. Nygaard and colleagues present here a robot that can adapt it’s morphology when it is detecting different terrain and learn which configuration is most effective.
We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing.
Coaxial Co3O4@polypyrrole (Co3O4@PPy) nanowire arrays have been successfully synthesized via a simple hydrothermal method and further a polymerization process. According to the composition and morphology characterization, it is found that a thin layer of amorphous PPy is uniformly coated on the surface of the Co3O4 nanowire. When directly used as an anode material for lithium-ion batteries, the Co3O4@PPy nanowire arrays electrode exhibits high reversible capacity, good rate capability, and improved cycling stability. A reversible capacity of 700mAhg−1 is sustained at the current of 3Ag−1 after 500 cycles, showing better cycling stability than the bare Co3O4 nanowire arrays (only 150mAhg−1 at the current of 3Ag−1after 100 cycles). Even at a high current of 20Ag−1, the Co3O4@PPy nanowire arrays can still maintain a capacity of 470mAhg−1, which is much higher than that of the bare Co3O4 nanowire arrays (158mAhg−1). The synergetic effect of the arrays structure and the PPy buffer layer contributes to the enhanced electrochemical performance of the Co3O4@PPy nanoarrys. As a result, the introduction of conductive polymer coating layer is an effective strategy to enhance the electrochemical performance of nanoarrays structure for advanced energy storage.
Fe3O4 nanospheres are synthesized by a solvothermal method with only one step under the assistance of surfactant. Fe3O4/C nanospheres are further fabricated by modifying Fe3O4 nanospheres with glucose as carbon source. The crystalline structure and surface morphology are investigated by a combination of X-ray diffraction, Roman spectroscopy, transmission electron microscopy and scanning electron microscopy. The results suggest that cubic Fe3O4 nanospheres are achieved, with a diameter around 200 nm. After the coating process, uniform carbon layer ~5 nm is formed on the surface of Fe3O4 spheres. The electrochemical performances of prepared Fe3O4 and Fe3O4/C nanospheres as anode materials for lithium-ion batteries are conducted via galvanostatic discharge/charge measurements and cyclic voltammetry. Under a current density of 100 mA g−1, the Fe3O4/C nanospheres exhibit a delithiation capacity of 767.2 mAh g−1 over 100 cycles with excellent capacity retention of 98.2% and improved rate capacities, both of which are better than those of Fe3O4 nanospheres. This work demonstrates that the prepared Fe3O4/C nanospheres can be a promising anode material for lithium ion batteries.
The vast majority of preclinical studies of HDAC inhibitors (HDAC-I) focus on the drug–target (cancer) cell interaction, whereas little attention is paid to the effects on non-target healthy cells, which could provide decisive information to eliminate potential cytotoxic compounds at a very early stage during drug development. In the current study we used cultures of primary rat hepatocytes as a read out system to select for the most potent HDAC-I in the group of structural analogues of an archetypal HDAC-I, namely Trichostatin A. This kind of approach allowed selecting compounds with high biological activity and with no apparent toxicity towards cultured hepatocytes.
A series of LiFe0.6Mn0.4PO4/C composites with different amount of multiwall carbon nanotubes (MWCNTs) has been successfully synthesized by introducing MWCNTs to LiFe0.6Mn0.4PO4 microspheres during the spray drying process. The as-prepared mesoporous spherical products (5–20 μm) are composed of primary nanoparticles (∼100 nm) and open-mesopores distribute both on the surface and inside the microspheres. XRD patterns and HRTEM images indicate that the as-prepared LiFe0.6Mn0.4PO4/C composites are well crystallized and no impurity phase is observed. As MWCNTs can entangle with the primary particles to form an interconnected conducting network, which can facilitate the electron transference, their existence can greatly enhance the conductivity between particles. Therefore, they can obviously increase the rate capability especially working at high current densities. Among the LiFe0.6Mn0.4PO4/C micro-spherical samples, the composite with 2% MWCNTs loading shows the best electrochemical performance, delivering a capacity of 163.3 mAh g−1 at 0.1 C, which is almost 96% of the theoretical capacity (∼170 mAh g−1). When discharged at 50 C, the composite still exhibits obviously higher capacity (64.23 mAh g−1) than the LiFe0.6Mn0.4PO4/C without MWCNTs (12.8 mAh g−1). Moreover, the MWCNTs embedded composite shows high cycle stability with no apparent capacity fading or voltage decay after 500 cycles at 45 °C.