batterydata/paper-abstracts huggingface dataset:
Three dimensional (3D) kesterite Cu2ZnSnS4 (CZTS) is synthesized by a facile solvothermal method using oxalic acid (OA) as additive agent. The as-synthesized CZTS samples are further annealed at 400°C in argon atmosphere to obtain the expected samples. The structure and morphology of the expected samples are characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technique. The results show that the Cu2ZnSnS4 takes on morphology of microspheres with ultrathin nanosheet constituents and has a stoichiometric composition. As a novel anode material for the lithium-ion batteries (LIBs), the as-prepared CZTS microstructures exhibit both high reversible capacity and good cycling performance at room temperature under a potential window from 3.0 to 0.01V (vs. Li+/Li) at current density of 100 mAg−1. The achieved initial discharge capacity is 1125 mAhg−1 and retained at 786 mAhg−1 after 100 cycles, which suggests that the kesterite CZTS can be a promising candidate as a novel anode material for the lithium-ion battery.
The layered LiNi1/3Mn1/3Co1/3O2 materials with good crystalline are synthesized by a novel method of hydrothermal method followed by a short calcination process. The crystalline structure and morphology of the synthesized materials are characterized by XRD, SEM. Their electrochemical performances are evaluated by CV, EIS and galvonostatic charge/discharge tests. The material synthesized at 850°C for 6h shows the highest initial discharge capacity of 187.7mAhg−1 at 20mAg−1. And the capacity retention of 97.9% is maintained at the end of 40 cycles at 1.0C. CV test reveals almost no shift of anodic and cathodic peaks after first cycle, which indicates good reversible deintercalation and intercalation of Li+ ions.
Nrf2:INrf2 (Keap1) are cellular sensors of chemical- and radiation-induced oxidative and electrophilic stress. Nrf2 is a nuclear transcription factor that controls the expression and coordinated induction of a battery of defensive genes encoding detoxifying enzymes and antioxidant proteins. This is a mechanism of critical importance for cellular protection and cell survival. Nrf2 is retained in the cytoplasm by an inhibitor, INrf2 which functions as an adapter for Cul3/Rbx1-mediated degradation of Nrf2. In response to oxidative/electrophilic stress, Nrf2 is switched on and then off by distinct early and delayed mechanisms. Oxidative/electrophilic modification of INrf2 cysteine 151 and/or protein kinase C phosphorylation of Nrf2 serine 40 results in the escape or release of Nrf2 from INrf2. Nrf2 is stabilized and translocates to the nucleus, forms heterodimers with unknown proteins, and binds the antioxidant response element, which leads to coordinated activation of gene expression. It takes less than 15 min from the time of exposure to switch on nuclear import of Nrf2. This is followed by activation of a delayed mechanism that controls the switching off of Nrf2 activation of gene expression. GSK3β phosphorylates Fyn at an unknown threonine residue(s), leading to the nuclear localization of Fyn. Fyn phosphorylates Nrf2 tyrosine 568, resulting in the nuclear export of Nrf2, binding with INrf2, and degradation of Nrf2. The switching on and off of Nrf2 protects cells against free radical damage, prevents apoptosis, and promotes cell survival.
A comparative study of crystallographic changes of the graphite anodes mixed with SiO x (in short, graphite-SiO x ) to the pristine graphite during the lithium insertion and extraction under a half-cell condition is conducted by using in situ XRD for the first time. The structural changes of the graphite-SiO x anodes are relatively quantified from the time-dependent alteration in a and c lattice constants of their contained graphite during the charge and discharge. The results clearly confirm that Li+ ions are inserted in the SiO x domain prior to graphite during the charge, and the delithiation takes place later in SiO x during the discharge consistently. Via this in situ XRD study, the electrochemical effect of the amount of silicon active materials in the graphite-SiO x is also monitored up to the 160% increase of the capacity.
UN Document [“Recommendations on the Transport of Dangerous Goods Manual of Tests and Criteria”, 3rd Revised Edition, 1999] outlines a test plan that is fundamental to the classification for transport of lithium batteries with metallic lithium, lithium alloy or lithium-ion intercalation electrodes. The tests can be divided into two categories: safety tests (internal and external short circuit, forced-over-discharge, charge) and environmental tests (reduced pressure, thermal, vibration and shock). These safety tests are intended to assess known unsafe behavior in abusive circumstances. This paper discusses the importance of environmental tests in the transport scenario and presents a discussion on how the existing safety tests provide only a false sense of security. Simple measures that prevent abuses in transport are suggested that would be more effective and ensure greater safety. A recent incident at Los Angeles International Airport (LAX), where lithium cells in transit were abused and caused to burn, is now cited by some regulators as proof that safety testing is required. This paper describes how that logic is flawed. Testing would not have prevented the LAX incident. Therefore, continued promotion of and focus on safety testing is working against the ultimate goal of improved safety in transport. This paper concludes that effective regulations should promote and maximize safe transportation of lithium batteries through environmental testing and the elimination of unsafe circumstances that enable lithium batteries to become a hazard in transport.
Advanced ionic liquid-based electrolytes are herein characterized for application in high performance lithium-ion batteries. The electrolytes based on either N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI), N-butyl-N-methylpyrrolidinium bis(fluoro-sulfonyl)imide (Pyr14FSI), N-methoxy-ethyl-N-methylpyrrolidinium bis(trifluoromethane-sulfonyl)imide (Pyr12O1TFSI) or N-N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide (DEMETFSI) ionic liquids and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt are fully characterized in terms of ionic conductivity, viscosity, electrochemical properties and lithium-interphase stability. All IL-based electrolytes reveal suitable characteristics for application in batteries. Lithium half-cells, employing a LiFePO4 polyanionic cathode, show remarkable performance. In particular, relevant efficiency and rate-capability are observed for the Py14FSI–LiTFSI electrolyte, which is further characterized for application in a lithium-ion battery composed of the alloying Sn–C nanocomposite anode and LiFePO4 cathode. The IL-based full-cell delivers a maximum reversible capacity of about 160 mA h g−1 (versus cathode weight) at a working voltage of about 3 V, corresponding to an estimated practical energy of about 160 W h kg−1. The cell evidences outstanding electrochemical cycle life, i.e., extended over 2000 cycles without signs of decay, and satisfactory rate capability. This performance together with the high safety provided by the IL-electrolyte, olivine-structure cathode and Li-alloying anode, makes this cell chemistry well suited for application in new-generation electric and electronic devices.
Nanoscale manganese dioxide particles supported onto carbon nanotubes (MnO2/CNTs) were prepared through a microwave-assisted reduction method and used as a catalyst for oxygen reduction reaction (ORR) in an alkaline environment. The MnO2 with high crystallinity and nanosized birnessite-type was obtained by microwave irradiated for 60 s repeating 3 times. Especially, the MnO2/CNTs exhibited a positive onset potential (− 8 mV vs. Hg/HgO) of ORR, which was similar to that of 20 wt% Pt supported on CNTs (Pt/CNTs). It was also found that the Koutecky–Levich plots of MnO2/CNTs suggested that its ORR proceeds via a 4-electron pathway. In addition, the accelerated durability tests indicated that the MnO2/CNTs composite catalyst was more stable than Pt/CNTs in 0.1 M KOH solution. The enhanced electrochemical activity and stability of MnO2/CNTs composite electrocatalyst can be attributed to the high electrical conductivity of CNTs and unique microstructure between MnO2 and CNTs, making it a promising candidate as an oxygen reduction catalyst in metal–air batteries and fuel cells.
Modification of natural graphite has recently moved into the focus of methods to prepare anode materials for lithium ion batteries. Here we report a treatment method for the modification of a common natural graphite employing oxidative solutions. Four solutions based on H2O2, Ce(SO4)2, HNO3 and (NH4)2S2O8 were employed; their effects were investigated with X-ray photoelectron spectroscopy, thermogravimmetric and differential thermal analysis, high resolution electron microscopy and measurement of electrochemical capacity. All oxidants resulted in marked improvements of reversible capacity, columbic efficiency in the first cycle and cycling behavior due to elimination of some imperfections with high activities towards lithium such as carbon chains, edge carbon atoms and sp3-hybridized carbon atoms, creation of more micropores/nano-channels, modification of the surface of natural graphite with a coverage of a dense layer of oxides, and improvement in stability of graphite structure. Effects of the oxidative solutions on electrochemical performance of natural graphite are compared.
In this paper we address the problem of local balancing in multi-hop wireless networks. We introduce the notion of proactive routing: after a short pre-processing phase in which nodes build their routing tables by exchanging messages with neighbors, we require that nodes decide the relay of each message without any further interaction with other nodes. Besides delivering very low communication overhead, proactive routing protocols are robust against some well known active attacks to network routing. In this framework, we develop a proactive routing protocol that is able to balance the local load. Experiments show that our protocol improves network lifetime up to 98% and that it delivers a network that is more robust against attacks that have the goal of getting control over a large part of the network traffic.
Covert person recognition was investigated longitudinally over a three-year period in a patient suffering from “Crossmodal Familiar Person Agnosia”, possibly due to a fronto-temporal dementia in its right temporal variant (Gentileschi et al., 2001). The progressive neuronal degeneration in the cortical regions critical for face recognition (viz., right infero-temporal areas) presented us with the opportunity to check Burton et al.'s (1991) and Farah et al.'s (1993) hypothesis on the dissociation between overt and covert face recognition in a neuropsychological condition which, however, is neurologically and cognitively different from that of focal “associative prosopagnosia”. Covert person recognition starting from overtly unrecognised faces was assessed by means of learning tasks of face/name association involving celebrities. It was assumed that some unconsciously spared information would selectively enhance the relearning rates when famous faces were paired with their true names. In fact, the true-name advantage (i.e., selective saving for experimental relearning of true name pairings) reached significance at first assessment, carried out five years from clinical onset. Effect faded away two and three years later on, thus abolishing the overt/covert dissociation in face recognition. These findings support Burton et al.'s (1991) and Farah et al.'s (1993) hypothesis of covert face recognition as the consequence of partial and incomplete activation of person semantics, due, in the present case, to the impoverishment of Gentileschi et al.'s (2001) “exemplar semantics” storehouse. Moreover, it turned out that covert recognition does not imply a different learning slope, but an overall different level of the learning profile.
In a series of experiments, the effect of white noise distortion and talker variation on lexical access in normal and Broca’s aphasic participants was examined using an auditory lexical decision paradigm. Masking the prime stimulus in white noise resulted in reduced semantic priming for both groups, indicating that lexical access is degraded by nonlinguistic white noise distortion. However, talker variation within a prime–target pair had no effect upon the performance of either the normal or aphasic individuals. The absence of a talker variation effect suggests that voice-specific information is not encoded in the lexical representations of words. The normal performance of Broca’s aphasics under conditions of both white noise and talker variation supports the view that these patients have a lexical processing impairment rather than a more generalized language deficit characterized by limited computational resources.
This comprehensive review discusses methods that have been used for the thermal management of photovoltaic modules. Particular attention has been paid to the use of phase change material (PCM) in the heat management of photovoltaic (PV), concentrating photovoltaic (CPV) and building integrated photovoltaic (BIPV) systems. Regulating the temperature of PV systems comprised of crystalline silicon cells appears to be the most economically viable for the use of PV/PCM systems, as increases in temperature have the most detrimental effect on the efficiency of silicon solar cells compared to organic or thin film cells. Studies have shown that the use of PCM helps to improve the performance of PV although there is still more to be explored and improved particularly the solidification and discharge of PCM.
Crystallinity structure plays a key role in the rate capability and cycling performance for rechargeable battery. However, the effect of crystallinity structure on sodium storage properties of VS2 hasn't been clearly elucidated. In this work, VS2 nanoarchitectures comprised of the nanosheets with single-crystal or polycrystalline structure are respectively synthesized by a facile solvothermal method, and the influence of crystallinity structure on their sodium storage properties is revealed. It is found that the single-crystal structure can largely enhance the Na+ intercalation kinetics in the crystal lattice and the structure stability during charge/discharge process. Therefore, the single-crystal VS2 electrode exhibits an enhanced rate capability and cycling performance, delivering a high capacity of 193 and 172 mAhg−1 at a high rate of 0.5 and 1.0 Ag−1, and 403 mAhg−1 after the following cycling test of 200 cycles at 0.2 Ag−1. This work opens up new insights for the exploration and design of high-performance electrode materials for sodium-ion batteries.
Lithium difluoro(oxalato)borate (LiODFB) (99.5%, by weight) is synthesized by an improved method, with the co-product of LiBF4 (99.5%, by weight). The electrochemical behaviors of sulfolane (SL) with LiODFB are studied by employment dimethyl sulfite (DMS) as a mixed solvent. It shows that 0.9molL−1 LiODFB-SL/DMS (1:1, by volume) electrolyte has considered stability against oxidative decomposition (>5.5V) and satisfactory conductivity. Electrochemical reductions of SL and DMS would occur nearly at the same level of ODFB anions. Further studies show that SL is the main and key reason during the formation process of an excellent solid electrolyte interphase (SEI) layer. When used in Li/MCMB cells, 0.9molL−1 LiODFB-SL/DMS electrolyte exhibits not only excellent film-forming characteristics, but also stable cycle performance. Besides, when used in LiFePO4/Li cells, 0.9molL−1 LiODFB-SL/DMS electrolyte exhibits several advantages, for example, the more stable electrochemical performances even at elevated and relatively low temperatures.
Being abundant in nature, biomass is the most attractive precursors of hard carbon (HC) anodes for Na-ion batteries (NIBs). The complexity of precursor has discouraged the development of a benchmark in synthesizing biomass-derived HC. Using longan peel as a model material, a facile two-step thermal treatment is proposed to avoid the self-activation, resulting in the HC with appropriate surface area and pore size distribution. A reversible capacity of 309 mAh g−1 is delivered with an initial Coulombic efficiency of 80%. As-prepared HC is further investigated at −20 °C to shed insights into the low temperature behavior of NIB for practical application. In/ex situ XRD and Raman spectroscopy are conducted, exhibiting a safe and reversible capacity of 250 mAh g−1 without Na plating at −20 °C for HC. The full cell consists of HC/Na3.5V2(PO4)2F3 is also examined. An energy density of 310 Wh kg−1 with an average discharge potential of 3.62 V is achieved at 25 °C, whereas the formation of unstable SEI at low temperature leads to the capacity fading of the full cell at −20 °C. This finding reports a low-cost and high energy density NIB, and unveil the critical challenge of using HC for the low-temperature application.
Owing to their high specific capacity, transition metal chalcogenides (TMCs) based materials attract enormous attentions for energy storage, yet the performance decay observed in TMCs anodes are strongly depended on the host material and working conditions. Here we report CoSe2 nanorods as a promising alternative for sodium-ion batteries (SIBs), which are fabricated by a facile hydrothermal strategy. At upper cut-off voltage of 0.4 V, the as-prepared sample can demonstrate improved sodiation capacity, rate capability, and cycling stability (a high capacity of 386 mAh g−1 at 5 A g−1 even after 2000 cycles). In situ XRD and ex situ TEM measurements are utilized to investigate phase transition behavior of CoSe2 nanorods in the initial 9 sodiation/desodiation cycles. The high electrochemical reversibility of CoSe2 nanorods within the potential window of 0.4–3.0 V is ascribed to that the deep conversion reaction below 0.4 V is effectively avoided, thus the volume expansion and pulverization of CoSe2 nanorods are efficiently suppressed. It convinces that applying suitable and optimal cut-off voltage is a useful approach to regulate the reactions progress for TMCs anode, improving their cycling and structure stability.
The authors regret that there was an error in equations (21) and (24) in the original paper published in Journal of Power Sources. The errors were in the equations in the printed article, but not in the actual equations used to generate the data in the figures. The correct equations should be(21)Msep=Vsep×ρsep(24)Mplate=Vunstplate×ρplate The authors would like to apologise for any inconvenience caused.
In this paper we reported for the first time the electrochemical behavior of pyrrolidinyl magnesium halide (C4H8NMgX, X=Br and Cl) dissolved in tetrahydrofuran (THF) with regard to potential application as electrolytes for rechargeable magnesium batteries. C4H8NMgX/THF solutions were characterized in term of conductivity, anodic stability, and reversibility of magnesium deposition and dissolution. Furthermore, the effect of metal substrates on magnesium deposition process was studied. Simple preparation, high cycling reversibility and moderate anodic stability of C4H8NMgBr/THF solution indicate the feasible application as the electrolyte for rechargeable magnesium batteries.
The carbon-coated monoclinic Li3V2(PO4)3 (LVP) cathode materials can be synthesized by a low temperature solid-state reaction route. The influences of different heat treatments on the LVP have been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical methods. In the range of 3.0–4.3V, both LVP/C electrodes present good rate capability and excellent cyclic performance. It is found that the sample (LVP1/C) prepared by the two-step heat treatment with pre-sintering at 350°C delivers the initial discharge capacity of 99.8mAhg−1 at 10C charge–discharge rate and still retains 95.8mAhg−1 after 300 cycles. For the sample (LVP2/C) synthesized by the one-step heat treatment, 95.9 and 90.0mAhg−1 are obtained in the 1st and 300th cycles at 10C rate, respectively. Our results based on the XRD patterns and the SEM images suggest that the good rate capability and cyclic performance may be owing to the pure phases, small particles, large specific surface areas and residual carbon. In the range of 3.0–4.8V, compared with the LVP2/C, the LVP1/C also exhibits better performance.
Nanowire-structured MnO2 active materials were prepared by a chemical precipitation method and their supercapacitive properties for use in the electrodes of supercapacitors were investigated by means of cyclic voltammetry in an aqueous gel electrolytes consisting of 1M Na2SO4 and fumed silica (SiO2). The MnO2 electrode showed a maximum specific capacitance of 151Fg−1 after 1000 cycles at 100mVs−1 when using the gel electrolyte containing 3wt.% of SiO2, which is higher than 121Fg−1 obtained when using the 1M Na2SO4 liquid electrolyte alone.
Multiwalled carbon nanotubes (MWCNTs) supported palladium-phosphorus nanoparticles (Pd–P/MWCNTs) catalyst is synthesized by homogeneous precipitation–reduction reaction method using hypohosphite as reducing agent. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis confirm that some P has entered into the crystal lattice of Pd and thus the Pd–P alloy is formed. Transmission electron microscopy (TEM) images reveal that Pd–P nanoparticles are uniformly dispersed on MWCNTs and the average particle size of Pd–P/MWCNTs catalyst is very similar to that of Pd/MWCNTs catalyst prepared by using NaBH4 as reducing agent. Cyclic voltammetric and chronoamperometric experiments show that the electrocatalytic activity and long-term operation stability of Pd–P/MWCNTs catalyst are better than that of Pd/MWCNTs catalyst for ethanol electrooxidation in alkaline media, indicating that the addition of P in Pd nanoparticles can promote the electrocatalytic activity and stability of Pd catalyst for ethanol electrooxidation.
Results of X-ray scattering measurements using synchrotron radiation on a Ni(111) single crystal electrode in 1M KOH are presented. On first immersion at the open circuit potential (OCP) the samples are shown to have a “duplex” two-layer oxide film, composed of an amorphous hydroxide outer layer separated from the Ni substrate by NiO 1–2 layers thick that display a NiO(111) orientation. The NiO layer is thinner than that for the air-formed oxide implying that a proportion of the NiO is converted to Ni(OH)2 following immersion in 1M KOH. This duplex oxide formed at the OCP is not removed at negative potentials up to onset of hydrogen evolution implying that more extensive reduction within hydrogen evolution is necessary to reduce the oxide. Cycling the potential over the Ni(OH)2/NiOOH redox peaks increases the thickness of both the inner oxide (NiO) and outer hydroxide layers. It is proposed that the thickening of this compact inner oxide leads to the self-limiting oxide growth observed during potentiodynamic cycling through the Ni(OH)2/NiOOH redox peaks. The crystalline NiO(111) present in the native oxide is removed by potential cycling over the redox peaks. The oxide and hydroxide layers electrochemically formed from 1M KOH show no sign of crystalline ordering.