batterydata/paper-abstracts huggingface dataset:
Varieties of nanostructured SnO2 have been widely investigated as promising anode material for next generation lithium-ion batteries (LIBs). However, traditional nanostructures suffer from re-agglomeration and excessive side reactions, which lead to low coulombic efficiency, poor rate performance and dramatic capacity decay. Here we develop an easy and robust strategy to fabricate carbon framework microbelts anchoring ultrafine SnO2 nanoparticles (U-SnO2 NPs@ CF-MBs), which takes advantage of the synergistic effect between high conductivity of large-size carbon framework and high activity of ultrafine SnO2 nanoparticles. The as-fabricated U-SnO2 NPs@C-BsF composite deliver high capacity of 925 mAh g−1 after 250 cycles at current density of 200 mA g−1, high rate capacity of 464 mAh g−1 at a high current density of 5000 mA g−1 and long cycle performance of 788 mAh g−1 after 1000 cycles at current density of 1500 mA g−1 in half cells. When applied in a full cell by coupling with a LiCoO2 cathode, the fabricated U-SnO2 NPs@ CF-MBs composite full cells keep a high capacity of 510 mAh g−1 after 80 cycles. Notably, the electrode exhibit two platforms located at 3.3 and 2.6 V, which indicate that the conversion between SnO2 and Sn is also highly reversible in full cells. The excellent lithium storage of large-scale U-SnO2 NPs@ CF-MBs ensures its great promise for commercial utilization in the future LIBs.
Conducting electroactive polymers are promising candidates for next-generation sodium-ion batteries due to their environmentally benign properties, high stability, and low cost. In this work, polyaniline (PANI) nanofibers have been successfully prepared by interfacial polymerization and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The effect of initiator concentration and interfacial contact area on the yield and surface morphology of PANI nanofibers has been studied. The yield and nanofibrous structure of PANI are found to be directly proportional to the interfacial contact area and the concentration of initiator. PANI nanofibers prepared from 1 M ammonium persulfate (APS) in a container having highest interfacial area of 200 cm2 has the highest yield of 0.9 and uniform nanofibrous structure which is clear from SEM study. Preparation of PANI nanofibers and doping with sodium-ion salt is confirmed by FTIR spectroscopy. Sodium-ion battery prepared with doped PANI delivered a highest discharge capacity value of 112 mAh g−1 at 0.047 mA cm−2 during initial cycling. The rate capability tests indicated that after cycling at different C-rates, the cell regained its initial discharge capacity value of 123 mAh g−1 at 0.047 mA cm−2.
To improve our understanding of indoor and outdoor personal exposures to common environmental toxicants released into the environment, new technologies that can monitor and quantify the toxicants anytime anywhere are needed. This paper presents a wearable sensor to provide such capabilities. The sensor can communicate with a common smart phone and provides accurate measurement of volatile organic compound concentration at a personal level in real-time, providing environmental toxicants data every three minutes. The sensor has high specificity and sensitivity to aromatic, alkyl, and chlorinated hydrocarbons with a resolution as low as 4 parts-per-billion (ppb), with a detection range of 4 ppb–1000 ppm (parts-per-million). The sensor’s performance was validated using Gas Chromatography and Selected Ion Flow Tube – Mass Spectrometry reference methods in a variety of environments and activities with overall accuracy higher than 81% (r 2 > 0.9). Field tests examined personal exposure in various scenarios including: indoor and outdoor environments, traffic exposure in different cities which vary from 0 to 50 ppmC (part-per-million carbon from hydrocarbons), and pollutants near the 2010 Deepwater Horizon’s oil spill. These field tests not only validated the performance but also demonstrated unprecedented high temporal and spatial toxicant information provided by the new technology.
Nanocrystalline strontium doped lanthanum manganite (La0.65Sr0.3MnO3) having variable particulate sizes and morphology is synthesized by a novel spray pyrolysis (SP) technique for solid oxide fuel cell (SOFC) cathode. Precalcined nanopowders received from the first SP run are added as the seeding agent in the subsequent runs for their in-situ growth inside the reactor. The suitability of the nano and micro particulates having interconnected porosity are examined as cathode functional and current collection layers. Detailed physical, microstructural and bulk electrical characterizations of such nanopowders are studied. Cathode polarization behavior and the associated rate limiting steps are characterized using AC impedance spectroscopy in the symmetric cell configurations. The optimization of the cathode processing conditions has brought the interfacial polarization down to ∼0.2 Ω-cm2 and thereby increases the cell performance from 2.0 to 3.2 A.cm−2 (0.7 V, 800 °C). Such improvement in anode-supported SOFC is correlated with the cathode processing conditions, particulate size, morphology and cathode microstructure.
In most cases, wireless sensor networks (WSNs) are deployed in unattended scenarios and are featured by energy sensitivity and low cost, thus making the performance of WSNs prone to the impact of external environment and internal energy. Existing routing protocols attempted to optimize the energy efficiency and routing reliability from the perspective of the network itself and failed to take into consideration the environmental impact from outside, causing them cannot make prompt reactions to the dynamic changes of the environments (e.g., wildfire). Thus, in these routing protocols the routing survivability under harsh environments is questionable. To tackle this issue, the paper proposes an environment-fusion multipath routing protocol (EFMRP) to provide sustainable message forwarding service under harsh environments. In EFMRP, routing decisions are made according to a mixed potential field in terms of depth, residual energy and environment. The basic idea of this approach is to instruct data packets to select routes with the best trade-off among latency, energy conservation and routing survivability. As the environmental field is constructed and updated using the sensing capability of WSN itself, constructed routes can avoid crossing through the danger zones to keep the paths safe. To enhance the performance of EFMRP, specific maintenance, traffic allocation and retreat mechanisms are proposed. We investigate the impact of configuration parameters and paths number on the routing performance respectively and compare EFMRP with respect to commonly used routing protocols. The experimental results show that EFMRP can obtain significant improvements in packet delivery ratio and network lifetime under harsh environments.
This paper describes an integrated approach for neuroimaging data acquisition, analysis and sharing. Building on methodological advances from the Human Connectome Project (HCP) and elsewhere, the HCP-style paradigm applies to new and existing data sets that meet core requirements and may accelerate progress in understanding the brain in health and disease.
NiFe2O4 porous nanorods/graphene composites are synthesized by a solvothermal method in combination with calcination at 400°C. Uniform NiFe2O4 porous nanorods with a diameter of about 300nm and a length of several micrometers are homogeneously anchored on graphene sheets. The close and firm contact between the two components assures the sound electrochemical properties. The lithium-ion battery performance of the composites anode is evaluated by galvanostatic and rate performance. NiFe2O4 porous nanorods/graphene composites electrode exhibit a superior lithium storage capability. The first discharge capacity of the composites electrode is 1115mAhg−1 at a current density of 1Ag−1, and still maintains at 655mAhg−1 even after 600 cycles. Even at a high current density of 5Ag−1, a high reversible specific capacity of 509mAhg−1 can be achieved. The synergistic effect between graphene with excellent electrical conductivity and NiFe2O4 nanorods with porous structure makes a substantial contribution to the outstanding electrochemical performance.
This paper presents the decision support technique and influencing factors in the design of an integrated solar-wind power system for stand-alone applications. Results of investigations on application of alternative energy facility like wind, photovoltaic (PV), and Integration of wind–PV power generating systems for Remote Area Power Supply have been presented. A weather model-based site matching of equipment and a simple numerical algorithm for generation unit sizing have been presented. The program has been used to determine the optimum generation capacity and storage needs for a stand-alone Wind, PV, and integrated wind–PV system for a remote site in India (Sukhalai situated near Suktawa in Hoshangabad district of Madhya Pradesh) that satisfies a typical load. Generation and storage units for each system are properly sized in order to meet the annual load demand for the above three scenarios. Annual average hourly values for load, wind speed, and insolation have been used for analysis. The results are used to justify the use of renewable energy source as a reliable option for remote areas.
The solid electrolyte interphase (SEI) remains a central challenge to lithium-ion battery durability, in part due to poor understanding of the basic chemistry responsible for its formation and evolution. In this study, the SEI on a non-intercalating tungsten anode is measured by operando neutron reflectometry and quartz crystal microbalance. A dual-layer SEI is observed, with a 3.7 nm thick inner layer and a 15.4 nm thick outer layer. Such structures have been proposed in the literature, but have not been definitively observed via neutron reflectometry. The SEI mass per area was 1207.2 ng/cm2, and QCM provides insight into the SEI formation dynamics during a negative-going voltage sweep and its evolution over multiple cycles. Monte Carlo simulations identify SEI chemical compositions consistent with the combined measurements. The results are consistent with a primarily inorganic, dense inner layer and a primarily organic, porous outer layer, directly confirming structures proposed in the literature. Further refinement of techniques presented herein, coupled with additional complementary measurements and simulations, can give quantitative insight into SEI formation and evolution as a function of battery materials and cycling conditions. This, in turn, will enable scientifically-guided design of durable, conductive SEI layers for Li-ion batteries for a range of applications.
This work summarizes the use of graphene/Co3O4 composites in electrochemical energy conversion and storage applications. Graphene is considered the most promising carbon material for accommodating multifarious nanoparticles and achieving excellent electrochemical performance, such as a high electrolyte contact area, electron transport rate and structural stability. This work presents different nanostructures of Co3O4 that consist of nanowires, nanotubes and ordered mesoporous structures, many of which have been poorly synthesized by facile strategies. Graphene can effectively house Co3O4 nanoparticles inside its 3D structure and greatly enhance the electrochemical performance of these nanoparticles. The synergistic effects of graphene and Co3O4 lead to a variety of attractive properties, such as excellent reversible capacity and good cycling stability. In addition, these unique properties are due to the many short diffusion pathways and active sites of nanosized Co3O4 and the elastic buffer space and conductive pathways provided by graphene. This comprehensive review outlines the excellent electrochemical performance of graphene/Co3O4 composites in electrocatalysis, supercapacitors, lithium-ion batteries and other batteries.
The rehabilitation of the former nuclear test site at Maralinga involved (among other processes) the removal of contaminated soil from an area of approximately 2.5 km2. The two most stringent rehabilitation criteria required measurements to ensure that no radioactive particle exceeding 100 kBq of 241Am activity, and no area of 1 ha exceeding 3 kBq/m2 of 241Am activity, remained in the rehabilitated area. The project timetable required that the area be scanned at the rate of approximately 3 ha/day. Two vehicle-mounted detection systems were developed and constructed to obtain the necessary measurements in the available timeframe. The scientific basis for the designs are presented, together with details of the selected equipment and technical solutions found. The performance of this equipment in the field is discussed in terms of both its scientific and technical operation. Based on the experience gained at Maralinga, improved versions of this equipment were produced under contract for the People’s Republic of China.
Vanadium nitride has been the hot material for supercapacitors due to its excellent electrical conductivity and high specific capacitance. However, vanadium nitride nanoparticle usually suffers a poor performance due to its aggregation and lack of effective contact. In this work, one-dimensional (1D) vanadium nitride nanofibers are prepared by a combination of electrostatic spinning and high-temperature calcination in ammonia. The cross-linked nanofibers composed of nanoparticles construct a facile transport path for charge and electrolyte ion. Moreover, vanadium nitride nanoparticles encapsulated into carbon prevent grain growth and aggregation, which provide more active sites for electrolyte ion. Owing to this unique structure, vanadium nitride nanofibers exhibit high specific capacitance of 291.5Fg−1 at 0.5Ag−1 and rate capability with a capacitance of 105.1Fg−1 at 6Ag−1. In addition, we find that annealing temperature has significant influence on the performance of vanadium nitride, which associates with fibrous structure and crystallinity, and a limited potential window can greatly improve the cycling stability (retains 50% of initial capacitance after 1000 cycles).
In isolated islands, usually diesel generators supply electric power. However, there are problems, e.g., a lack of fossil fuel, environmental pollution etc. So, isolated island, e.g. Miyako island, installs renewable energy power production plants. However, renewable energy power production plants are very costly. This paper presents an optimal configuration of power system in isolated island installing renewable energy power production plants. The generating system consists of diesel generators, wind turbine generators, PV system and batteries. Using the proposed method, operation cost can be reduced about 10% in comparison with diesel generators only from simulation results.
Chemical states and structural changes accompanying the electrochemical Li deintercalation of Li1−x Mn2−y Cr y O4 (y=1/9,1/6,1/3) were studied by the in situ X-ray absorption fine structure (XAFS) technique. The X-ray absorption near-edge structures (XANES) of Mn and Cr as a function of x showed that the 4V plateau of the material can be ascribed to the oxidation of Mn3+ to Mn4+, and Cr does not contribute to the charging, but to the stabilization of the spinel structure against the delithiation. The extended EXAFS analysis of Li1−x (Mn, Cr)2O4 revealed that the Jahn–Teller distorted Mn3+–O octahedra become uniform when the cell is fully charged.
Carbon host materials play an important role in improving the electrochemical performances of lithium-sulfur batteries. In this work, a novel, cloud cap-like and phosphorus/nitrogen co-containing biomass carbon material derived from mushroom as cathode host materials for lithium sulfur batteries were fabricated by a facile H3PO4 activation method. The porous carbon carbonized at 650°C contains abundant micro/mesopores and possesses the high BET surface area of 788m2 g−1 and the main pore size of 1.1–2.5nm, which can boost the adsorption of sulfur and polysulphides by melt-diffusion technology. The sulfur/biomass carbon composite delivers the high initial specific capacity of 1357.8mAhg−1 at 0.1C and high capacity retention of 729mAhg−1 after 100 cycles due to its specific porous structure. The relatively high discharge capacity of 213mAhg−1 is exhibited in the composite even after 72 cycles at higher discharge rates (0.2C, 0.3C, 0.5C, 1C and 2C). All these superior performances well validate the excellent stability and reversibility of the biomass porous carbon as a promising cathode matrix for lithium-sulfur batteries. In addition, the biomass carbon derived from mushroom contains simultaneously phosphorus and nitrogen, which can improve the specific capacity. For the present carbon materials, the special porous structure may encapsulate sulfur particles, inhibit the dissolution of polysulphides in the electrolyte and thus lead to the excellent performances of the materials. Our study shows that the porous biochar arising from mushroom can be easily fabricated and considered as the promising conductive materials for high performance lithium-sulfur batteries.
Analyzing samples with PCR is routine in the lab. New approaches let researchers do this assay wherever they need.
The lithium deposition–dissolution process in solid polymer electrolytes containing Al2O3 filler treated under different conditions has been investigated comparing with the ionic conduction behavior of the electrolyte. The composite electrolytes were prepared from poly(ethylene oxide) (PEO), LiBF4 and α-Al2O3 filler by using a dry process, where the surface of α-Al2O3 was beforehand modified by a wet process. The exchange current densities, i 0, of the lithium electrode process in P(EO)20LiBF4 with and without Al2O3 filler were determined by a micro-polarization method. The temperature dependence of i 0 provided similar values for activation energy, ca. 25 and 70kJmol−1 in both temperature regions above and below 60°C, respectively. The effect of the surface treatment of the filler on the lithium electrode process gave a different tendency from that on the ionic conductivity. The Al2O3 surface treated by alkali solution enhanced the electrode process to the largest extent among the fillers used here, while it led to rather poor cycling stability in voltammetry. The enhanced reaction rate at the lithium electrode/solid polymer electrolyte interface has probably resulted in the improved ion dissociation by the surface groups of the Al2O3 filler.
Li-ion batteries have been widely used in the EVs, and the battery thermal management is a key but challenging part of the battery management system. For EV batteries, only the battery surface temperature can be measured in real-time. However, it is the battery internal temperature that directly affects the battery performance, and large temperature difference may exist between surface and internal temperatures, especially in high power demand applications. In this paper, an online battery internal temperature estimation method is proposed based on a novel simplified thermoelectric model. The battery thermal behaviour is first described by a simplified thermal model, and battery electrical behaviour by an electric model. Then, these two models are interrelated to capture the interactions between battery thermal and electrical behaviours, thus offer a comprehensive description of the battery behaviour that is useful for battery management. Finally, based on the developed model, the battery internal temperature is estimated using an extended Kalman filter. The experimental results confirm the efficacy of the proposed method, and it can be used for online internal temperature estimation which is a key indicator for better real-time battery thermal management.
Earlier studies of nursing home patients show a high prevalence of dementia, neuropsychiatric symptoms (NPS), pain, and dependency in activities of daily living. The REDIC-NH cohort was set up to study the disease course and the resources used in patients with dementia in Norway. The aim of this paper was to describe the methods and the data collection, and to present selected data about patients at admission to a nursing home.
Two new types of Si patterned surfaces are presented that have either a solid micropyramid structure or a double microstructure in which nanopores are induced on the pyramid surface. The pyramid diameter ranges between 1 and 6 μm, while the pores are 50–100 nm in diameter and ∼100–400 nm deep. It is illustrated that when they are employed as anodes, in Li-ion batteries, these patterned anodes, at high current densities of 1C, can (i) retain their initial morphology intact, despite the ∼400% expansion that Si experiences upon lithiation, and (ii) minimize the formation of the solid electrolyte interface (SEI) that forms upon decomposition of the electrolyte. Furthermore, for the nanoporous-micropyramids, scanning electron microscopy after twenty-five electrochemical cycles reveals that no fracture occurs in either high (1 C) or low (0.1 C) current densities. This is a unique and significant observation as similar experiments, at 0.1 C, on the solid micropyramid surfaces indicate severe fracture from the first Li-insertion. It is therefore concluded that introducing a nanostructure on micropyramids significantly enhances their structural stability. This suggests that microscale Si with induced nanopores is an alternative anode candidate to nanoscale Si.
This paper deals with an experimental evaluation regarding the real performance of lithium based energy storage systems for automotive applications. In particular real working operations of different lithium based storage system technologies, such as Li[NiCoMn]O2 and LiFePO4 batteries, are compared in this work from the point of view of their application in supplying full electric and hybrid vehicles, taking as a reference the well-known behavior of lead acid batteries. For this purpose, the experimental tests carried out in laboratory are firstly performed on single storage modules in stationary conditions. In this case the related results are obtained by means of a bidirectional cycle tester based on the IGBT technology, and consent to evaluate, compare and contrast charge/discharge characteristics and efficiency at constant values of current/voltage/power for each storage technology analyzed. Then, lithium battery packs are tested in supplying a 1.8kW electric power train using a laboratory test bench, based on a 48V DC bus and specifically configured to simulate working operations of electric vehicles on the road. For this other experimentation the test bench is equipped with an electric brake and acquisition/control system, able to represent in laboratory the real vehicle conditions and road characteristics on predefined driving cycles at different slopes. The obtained experimental results on both charge/discharge tests and driving cycles demonstrate the advantages of using lithium technologies, mainly in terms of their high efficiency, particularly at high current values. That represents a feasible solution to offer vehicle designers and users extended driving ranges and reduced recharging times.
A study of a direct methanol alkaline fuel cell (DMAFC) operating with sodium conducting membranes is reported. Evaluation of the fuel cell was performed using membrane electrode assemblies incorporating carbon supported platinum catalysts and Nafion® 117 and 112 membranes. A membrane electrode assembly was also prepared by the direct chemical deposition of platinum into the surface region of the membrane. Evaluation of the chemically deposited assembly showed it to be less active than those based on carbon supported catalysts. SEM & TEM analysis indicate that this behaviour is due to the low surface area of the chemically deposited catalyst layer. The fuel cell performance with Nafion membranes is reported and is not as good as achieved with hydroxide ion conducting membranes suggesting that Nafion may not be suitable for DMAFC operation.