batterydata/paper-abstracts huggingface dataset:
A novel anode material for lithium-ion batteries, graphene-wrapped Si nanoparticles (NPs) embedded in carbon composite nanofibers (CCNFs) with G/Si, is fabricated by electrospinning and subsequent thermal treatment. In CCNFs with G/Si, Si NPs are distributed and preserved inside the CNF surface because the graphene wrapping the Si NPs help prevent agglomeration and ensure a good dispersion of Si NPs inside the CNF matrix. 20-GSP prepared from a weight ratio of 20 wt% of G/Si to polyacrylonitrile exhibits stable capacity retention and a reversible capacity of above 600 mAh g−1 up to 100 cycles. The high cycling performance and superior reversible capacity of the 20-GSP anode can be attributed to the one-dimensional nanofibrous structure with non-agglomerated Si NPs in the CNF matrix, which promotes charge transfer, maintains a stable electrical contact, and buffers the Si volume expansion.
Micropopous chicken feather carbon (CFC) severing as electrode materials for the first time is prepared via the activation with KOH agent to different extents. The structure and electrochemical properties of CFC materials are characterized with N2 adsorption/desorption measurements, X-ray diffraction (XRD), transmission electron microscope (TEM), cyclic voltammetry (CV), galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy (EIS). The obtained results show that CFC activated by KOH with KOH/CFC weight ratio of 4/1 (CFCA4) possesses the specific surface area of 1839 m2 g−1, average micropore diameter of 1.863 nm, and exhibits the highest initial specific capacitance of 302 F g−1 at current density of 1 A g−1 in 1 M H2SO4, and that even after 5000 cycles, CFCA4 specific capacitance is still as high as 253 F g−1. Furthermore, CFCA4 also delivers specific capacitance of 181 F g−1 at current density of 5 A g−1 and 168 F g−1 at current density of 10 A g−1. Accordingly, the microporous activated carbon material derived from chicken feather provides favorable prospect in electrode materials application in supercapacitors.
The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuel-efficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability.
Diminished glucose metabolism accompanies many neurodegenerative diseases including Alzheimer’s disease. An understanding of the relation of these metabolic changes to the disease will enable development of novel therapeutic strategies. Following a metabolic challenge, cells generally conserve energy to preserve viability. This requires activation of many cellular repair/regenerative processes such as mitophagy/autophagy and fusion/fission. These responses may diminish cell function in the long term. Prolonged fission induces mitophagy/autophagy which promotes repair but if prolonged progresses to mitochondrial degradation. Abnormal glucose metabolism alters protein signaling including the release of proteins from the mitochondria or migration of proteins from the cytosol to the mitochondria or nucleus. This overview provides an insight into the different mechanisms of autophagy/mitophagy and mitochondrial dynamics in response to the diminished metabolism that occurs with diseases, especially neurodegenerative diseases such as Alzheimer’s disease. The review discusses multiple aspects of mitochondrial responses including different signaling proteins and pathways of mitophagy and mitochondrial biogenesis. Improving cellular bioenergetics and mitochondrial dynamics will alter protein signaling and improve cellular/mitochondrial repair and regeneration. An understanding of these changes will suggest new therapeutic strategies.
A non-enzymatic amperometric sensor using natural molybdenite (MLN) electrodeposited with methylene blue (MB) has been fabricated and characterized and its analytical performances were investigated for the determination of ascorbic acid (AA). The surface morphology of the electrode modified by electrodeposited MB was studied by use of the Advanced Mineral Identification and Characterization System (AMICS) and laser confocal high-temperature scanning microscope (LCSM). The poly(MB) and MLN immobilized sensor showed good stability, reproducibility, sensitivity, and selectivity. It exhibited a linear performance range from 3 to 1000 μM, with a lower detection limit of 0.083 μM (signal/noise = 3) and short response time (< 5 s). No obvious decrease in the current was observed after 20 days storage. The methodology reproducibility of this sensor was 2.6%. It showed good anti-interference ability for the potential interfering compounds. The poly(MB) film not only can enhance the electron-transfer rate but also increase the lifetime of the sensor. This study demonstrated the applicability of natural molybdenite for the fabrication of non-enzymatic electrochemical AA sensor.
Double-layer capacitor electrolytes employing allyl-functionalized ionic liquids as electrolytes with solvents have been evaluated. Imidazolium cations with allyl groups enabled the high capacitances and low resistances of electric double-layer capacitor (EDLC) cells at a wide range of temperature in spite of the large cation sizes and low ionic conductivities of the electrolytes compared to imidazolium with saturated alkyl groups, 1-ethyl-3-methylimidazolium (EMIm). The improvement of EDLC performance was noted particularly in the case of diallylimidazolium (DAIm) cation and TFSA anion. The substitution of the vinyl group increased the high capacitance only at 298K and decreased the capacitance at low temperature and direct current resistance (DC-IR) at 243 and 298K. The butenyl group deteriorated the capacitance and DC-IR at 243 and 298K. The stability of EDLC cell of DAIm–BF4/PC was inferior to that of EMIm–BF4/PC. The addition of DMC to PC improved the stability.
Standalone MicroGrid (MG) suffers from high voltage unbalancing due to both single phase and unbalanced loads. This paper presents a comprehensive survey about the available techniques and controllers for MG power quality improvement. Recent trends and schemes for the standalone MG power quality improvement are reported in detail. The techniques which concern with the MG voltage unbalancing issue are highlighted. In addition, this paper develops a simple scheme for balancing the MG phase voltages. The proposed scheme employs a new interfacing inverter topology and control. The three phase compact unit interfacing inverter of the Distributed Generators (DGs) has been rebuilt in form of three single phase inverter units. Each single phase inverter unit is controlled independently to achieve MG phase voltage balancing. At different load operating conditions, the three single phase inverter units run at different values and types (leading or lagging) power factors (PF). Employing the proposed inverter control achieves perfect phase voltages balancing at the most MG buses. Before employing the proposed inverter control, the voltage unbalancing ratio at some buses exceeds than 6%. This ratio approximately shrinks to zero after including the proposed inverter control. The performance of the proposed inverter control has been tested under different load conditions. In addition, the performance of the proposed inverter control is compared with both the old inverter control (unity power factor inverter) and the conventional inverter control (constant power factor inverter) performance. Only, a simple modification to the old inverter control is sufficient to implement the new inverter control. The proposed inverter control is very simple and highly economical attractive.
Rationalizing energy consumption in smart buildings is considered in this paper, and a wireless monitoring system based on Passive Infrared sensors (PIRs) is proposed. The proposed system is pervasive and can be integrated in existing buildings without any complicated wiring or setting. Realistic constraints are considered for this purpose such as sensing-hole, battery limitation, user comfort, etc. To ensure maximum coverage in presence of holes, the optimal placement of PIRs is formulated as a mixed integer linear programming optimization problem (MILP). Experimentations have been carried out to quantify the effects of the holes on the detection accuracy and to demonstrate the impact of the optimal PIRs placement on energy consumption. To facilitate installation and integration without complicated settings, notably in existing buildings, the system is designed to be battery operated. Therefore, energy efficiency will not be limited to optimize energy consumption in buildings, but also to optimize consumption in the components of the system (sensors and actuators). Duty cycling is inevitable to extend the network lifetime of such components, but the setting of this cycle yields a trade-off in optimizing the energy consumption i) at the building level, vs., ii) that consumed by sensors and actuators. Reducing energy consumption (duty cycle) of sensors/actuators will delay non-occupancy detections and thus will increase the building energy wastage, and vice-versa. Duty cycling the radios is dealt with and modeled as a cooperative game, which allows to derive a Nash Bargaining as the optimal balancing cycle. The proposed approach is analytically investigated using realistic parameters of the existing hardware and users’ comfort. The results demonstrate that the system can survive for more than 6 years without battery replacement.
This paper reports a numerical study of energy consumption and time efficiency of sensor networks with five different structural topologies and four different routing methods, regarding their performances and costs, which might provide some references and guidelines for designing sensor networks under various conditions for possible applications.
Biosorption of manganese(II) using suspended and immobilized cells of fungal Penicillium camemberti (biomass) and nano-P. camemberti (nano-biomass) was studied by evaluating the physicochemical parameters of the solution such as initial manganese ion concentration, pH, temperature, dosage, and contact time in both batch system and fixed bed column. The maximum biosorption obtained from the batch process was 91.54 and 71.08 % for nano-biomass and biomass in initial concentration of 5 ppm, respectively. The Langmuir, Freundlich, Temkin, and BET isotherms isotherm models were used in the equilibrium modeling. The correlation coefficient of more than 0.90 turned out that the adsorption process of Mn(II) on biomass and nano-biomass were in accordance with both Langmuir and Freundlich isotherms. The sorption process followed a second-order rate kinetics indicating the process to be diffusion controlled. The results also demonstrate that an intra-particle diffusion mechanism plays a significant role in the sorption process. The structure of P. camemberti was characterized by FT-IR spectrums.
Rechargeable secondary batteries (RSBs) have been practiced successfully for over one hundred years and now lithium-ion batteries (LIBs) represent the best-commercialized RSBs. However, the state-of-the-art LIBs are still not sufficient in many aspects to power electrical vehicles. In this context, research efforts are being intensively invested on developing next-generation LIBs. On the list of promising battery materials, silicon (Si) is particularly attractive as an anode material of LIBs, ascribed to its richness in the earth and extremely high capacity (∼3500mAhg−1 at room temperature). With the successful utilization of Si as anodes, LIBs would enable much higher energy density. However, Si anodes suffer from several issues technically, including huge volume changes, unstable interface between Si and electrolyte, and low conductivity. Aimed at addressing these challenges, various technical strategies have been investigated. Recently, atomic and molecular layer deposition (ALD & MLD) have emerged as two new research thrusts for LIBs and have demonstrated tremendous capabilities to resolve the issues of Si anodes. In this work, we for the first time made this comprehensive review on a variety of inorganic and organic coatings via ALD and MLD for achieving high-performance Si anodes in LIBs.
MgNi-based alloys have been regarded as very promising anode material for nickel-metal hydride battery owing to their electrochemcial capacity much higher than that of AB5 alloys. However, MgNi alloy anodes generally suffer very serious capacity decay in cycling, which is previously ascribed to the corrosion of Mg in alkali electrolyte in the past decades. To further reveal the capacity fading mechanism of MgNi-based alloys, the electrochemcial hydrogen storage properties of Mg2Ni and amorphous Mg50Ni50 alloys and their microstructural evolution during cycling were comparatively studied. It has been firstly demonstrated that it is the amorphous MgNi phase instead of Mg2Ni phase contributes to electrochemical discharge capacity, because the Mg2NiH4 hardly released hydrogen under electrochemcial conditions. Then, it has been found that the charge input level has significant effect on the cyclic performance of amorphous Mg50Ni50 alloy anode. At full charge of 500 mAh g−1, the amorphous MgNi phase easily crystallized to the nanocrystalline Mg2NiH4, which leaded to the capacity decay immediately. Comparatively, with the low charge input of 100 mAh g−1, the discharge capacity of amorphous Mg50Ni50 alloy remained almost unchanged for 425 cycles. The excellent cyclability is attributed to the less hydrogenation-induced crystallization at low charge input. This work clearly demonstrates that the hydrogenation-induced crystallization is a dominating reason for the electrochemical capacity decay in the milled amorphous MgNi anode. It provides a new approach to improve the electrochemcial properties of MgNi alloy electrode by inhibiting the hydrogenation-induced crystallization.
The electronic structure of the electrochemically Li-ion deintercalated Li1−x Mn2O4 system has been investigated for various Li compositions using soft X-ray absorption spectroscopy (XAS) for oxygen K-edge and Mn LII,III-edge. To get reasonably good XAS spectra for the electrochemically Li-ion deintercalated Li1−x Mn2O4 system, we made a binder free LiMn2O4 film electrode using electrostatic spray deposition (ESD) technique. From the Mn LII,III-edge XAS, it is found that the peak shifts to higher energy with the Li-ion deintercalation and this is due to the increase of the average oxidation state of the Mn ion. From the oxygen K-edge XAS, the Li-ion deintercalation gives rise to a gradual increase in pre-edge peak intensity but mostly does not effect its peak shape.
Nanoporous anatase TiO2 (np-TiO2) electrodes have been developed via the anodization of titanium foils in fluoride containing electrolytes, and its application in rechargeable lithium-ion batteries (LIBs) was investigated. Four different types of np-TiO2 electrodes with different pore diameters of 14.7±8.2 nm, 12.8±6.8 nm, 11.0±5.5, and 26.7±13.6 nm were fabricated for evaluating the effect of nanoporous characteristics on the LIB performance. The discharge capacity of the four battery types 1, 2, 3, and 4 were 132.7 mAh·g−1, 316.7 mAh·g−1, 154.3 mAh·g−1, and 228.4 mAh·g−1, respectively. In addition, these electrodes 1, 2, 3, and 4 exhibited reversible capacity of 106.9 mAh·g−1 after 295th, 180.9 mAh·g−1 after 220th, 126.1 mAh·g−1 after 150th, and 206.7 mAh·g−1 after 85th cycle at a rate of 1 C, respectively. It was noted that the cyclic life of the batteries had an inverse relationship, and the capacity had a proportional relationship to the pore diameter. The enhanced electrochemical performance of the nanoporous electrodes can be attributed to the improved conductivity and the enhanced kinetics of lithium insertion/extraction at electrode/electrolyte interfaces because of the large specific surface area of np-TiO2 electrodes.
β-Mn2V2O7, for the first time, is synthesized by a simple and cost-effective zeolitic imidazolate framework precipitation technique using water as the sole solvent and reported for excellent electrochemical Li storage properties. The anode delivers specific capacities of 868 and 751 mA h g−1 at rates of 500 and 2000 mA g−1 after 180 and 400 cycles, respectively.
A practical and inexpensive method for producing Si/C composite as ready-to-use active material for Li-ion battery anode has been developed. Three-component powders (<63 µm) were synthesized by embedding micro-sized silicon (8–24 wt%) and synthetic battery-grade graphite (60–75 wt%) in a pitch-derived carbon matrix. The procedure consisted of short mechanical milling of silicon with toluene/pitch suspension followed by mixing with graphite and final heat-treatment at 1,100 °C. X-ray diffraction was applied for determining the structural characteristics of the composite and impurities present. A series of anodes were prepared by using CMC and PVDF binder. The dispersion of silicon particles in the carbon matrix and spreading of the binder into the anodic film were monitored using the SEM–EDX technique. Lithium insertion/deinsertion performance was assessed from the galvanostatic charge–discharge characteristics using a Si/C–lithium two-electrode cell. Embedding silicon in well conductive pitch coke as well as reducing the content of carbon black as percolator allowed the first cycle irreversible capacity to be decreased to 90 mAh g−1. An initial reversible capacity of 620 mAh g−1 for 12 wt% of Si in the composite, with average capacity decay of 0.3 % per cycle, was achieved thanks to a specific composite structure as well as profitable physicochemical properties of the CMC binder. Intensive press-rolling of the anodic film allowed the packing density to be increased up to 1.35 g cm−3 (9.5 mg cm−2 at thickness of 70 µm) and, as a result, an outstanding volumetric capacity up to 670 mAh cm−3 could be achieved, without changing the cycling properties.
An amorphous Ti2Ni alloy, prepared by mechanical milling of a crystalline Ti2Ni alloy, was heat-treated at several temperatures. The crystalline behavior of the amorphous alloy was studied , relative to a multi-stage crystallization mode, using X-ray diffraction, differential scanning calorimetry, and electron diffraction. X-Ray photoelectron spectroscopy was performed to analyze the surface structure of the alloys. The alloy that was heat-treated at 693 K, with a non-equilibrium bulk structure and a protective surface layer, has a high discharge capacity and good cycling stability. The issue of severe capacity loss of Ti2Ni-based alloys, which has caused problems for many years, has been significantly improved.
The thermal and electrochemical stability, as well as compatibility with various bench mark cathode and anode materials of two new lithium fluoride salt (LiF) based electrolytes have been studied. These two new electrolytes are formed by using boron-based anion receptors, tris(pentafluorophenyl) borane (TPFPB), or tris(2H-hexafluoroisopropyl) borate (THFPB) as additives, which were designed and synthesized at Brookhaven National Laboratory (BNL), to dissolve the LiF salt in carbonate solvents. The transference number of Li+ for these electrolytes is as high as 0.7 and the room-temperature conductivity is around 2×10−3 Scm−1. The electrolytes containing propylene carbonate (PC) show superior low-temperature conductivity properties. The electrochemical window is approaching 5.0V. It was also found that the new electrolytes work well with LiCoO2 or LiMn2O4 cathodes. However, when PC containing electrolytes were used, PC co-intercalation is still a problem for graphite anodes. The formation of a stable solid electrolyte interface layer on the surface of anode in this type of electrolyte needs to be studied further.
A porous composite membrane with P(VDF-HFP) as host and nonwoven as reinforcement has been successfully prepared and reported in this paper. The tensile strength of the composite is very close to that of Celgard 2730 separator in both wet and dry state. The Na+ ionic conductivity of the given gel-type composite membrane (0.82mScm−1) absorbed NaClO4 organic liquid electrolyte at room temperature has found to be four times higher than that of the commercial separator saturated with the same electrolyte (0.16mScm−1). It has also showed enhanced transference number of Na+ ions and good electrolyte retention even at 110°C. The electrochemical reversibility for Na4Mn9O8 cathode has been confirmed by cyclic voltammetry by using the aforementioned gel polymer electrolyte (GPE). The porous composite GPE exhibits great application prospect for sodium ion batteries with high energy density.
The β-modification of Li3VF6 is easily prepared following a precipitation reaction at moderate temperature avoiding the high temperature route normally used for preparing related fluorides. Precipitation conditions for Li3VF6 have been optimized for two different alcohols to obtain better electrochemical performances. Temperature has been found to play an important role in the progress of precipitation reaction and in the phase purity of the resulting product. Best results were achieved for 2-propanol based solutions at 60°C and for ethanol based solutions at 45°C containing VCl3, HF(aq) and Li2CO3 as starting compounds. In both cases large agglomerates, though of different size and shape, are obtained. These are composed of smaller particles of 20–30nm. Electrochemical performances of as prepared Li3VF6 materials as electrode in lithium rechargeable batteries are modest with a maximum capacity of only 30mAhg−1. However, processing these materials by ball milling with carbon allows the capacity to increase to its theoretical value, 144mAhg−1, accordingly to the complete reduction of V3+ to V2+. The observed average reduction potential for V3+ to V2+, 2V, may be certainly higher than that found in oxides but not high enough to be considered for application as the positive electrode. However, Li3VF6 is then another example of the β-Li3MF6 type-structure hosting lithium through an electrochemical insertion reaction. On the other hand, reversible oxidation of V3+ through lithium de-insertion, which would lead to the formation of Li3−x VF6 phases has not been successful yet. Taking into account the redox intercalation chemistry of vanadium in oxides, the reversible reduction of V3+ to V2+ and the irreversible oxidation of V3+ to V4+ in the herein presented fluoride make a significant difference derived from the nature of the non metal X. Then, research of fluorides is a path to find new chemistries for lithium batteries.