batterydata/paper-abstracts huggingface dataset:
As a promising salt for lithium-ion batteries, lithium difluoro(oxalate)borate (LiODFB) has become a research hotspot in recently. In this work, LiODFB-based electrolytes are studied. When used in Li/MCMB (mesophase carbon microbeads) cells, cell with 0.9 M LiODFB–ethyl methyl carbonate (EMC)/sulfolane (SL) (1:1, v/v) electrolyte shows lower impedance than ones with 0.9 M LiODFB–EMC/ethylene carbonate (EC) (1:1, v/v) electrolyte. Reduction of impedance mainly dues to the fitting nature of solid electrolyte interphase (SEI) film on carbon electrode of lithium-ion battery. The changing morphologies of SEI films with increased circulation numbers were analyzed by scanning electron microscope (SEM). And C2H5OLi, C2H5CO3Li, Li2CO3, RSO3Li, Li2SO3, LiF, C2H5F and some complicated mesh compounds based on >B–O– bond, were found in SEI film by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). It was believed that the root of impedance reduction benefits from both the rich existence of sulfurous compounds and the low content of LiF in SEI film.
The spinel LiNi0.5Mn1.5O4 powders with high crystallinity and well-developed octahedral morphology were synthesized by a ultrasonic spray pyrolysis method using citric acid as a polymeric agents. The LiNi0.5Mn1.5O4 powders were characterized by X-ray diffraction, scanning electron microscopy, and electrochemical testing. The LiNi0.5Mn1.5O4 material delivers a discharge capacity of more than 138mAhg−1 with excellent capacity retention of more than 97% after 50 cycles even at 55°C.
Abstract Securing ad hoc routing protocols for MANETs is a significant challenge due to number of reasons: (1) mobility results in continuously changing network topology – the premise of stable self or non-self is void, (2) the proposed security solution must be lightweight so that it can be deployed on resource constrained mobile nodes, and (3) the solution should provide high detection accuracy and low false positive rate. The major contribution of this paper is a hybrid AIS model – combining the relevant features of classical self/non-self paradigm with the emerging danger theory paradigm – that has the capability to meet the above-mentioned challenges of the MANET environment. As a case study, we use our hybrid model to develop a power aware security framework for BeeAdHoc– a well-known bio-inspired routing protocol. We have realized our framework in ns-2 simulator. We have also developed an attacker framework in ns-2 that has the capability to launch a number of Byzantine attacks on BeeAdHoc. The results of our experiments show that our proposed framework meets all its requirements: (1) the adaptive learning because of changing self/non-self, (2) high detection accuracy and low false positive rate, (3) lightweight in terms of processing and communication overheads, and (4) better or comparable performance compared with non-secure versions of existing state-of-the-art MANET routing protocols – DSR and AODV. We have also compared our hybrid AIS model with self/non-self, danger theory and a conventional anomaly detection system to show its merits over these schemes. Finally, we propose an extension of the framework for securing DSR.
Schemas are abstract nonverbal representations that parsimoniously depict spatial relations. Despite their ubiquitous use in maps and diagrams, little is known about their neural instantiation. We sought to determine the extent to which schematic representations are neurally distinguished from language on the one hand, and from rich perceptual representations on the other. In patients with either left hemisphere damage or right hemisphere damage, a battery of matching tasks depicting categorical spatial relations was used to probe for the comprehension of basic spatial concepts across distinct representational formats (words, pictures, and schemas). Left hemisphere patients underperformed right hemisphere patients across all tasks. However, focused residual analyses using voxel-based lesion-symptom mapping (VLSM) suggest that (1) left hemisphere deficits in the representation of categorical spatial relations are difficult to distinguish from deficits in naming these relations and (2) the right hemisphere plays a special role in extracting schematic representations from richly textured pictures.
Haptic feedback plays a large role in enhancing immersion and presence in VR. However, previous research and commercial products have limitations in terms of variety and locations of delivered feedbacks. To address these challenges, we present HapticSnakes, which are snake-like waist-worn robots that can deliver multiple types of feedback in various body locations, including taps-, gestures-, airflow-, brushing- and gripper-based feedbacks. We developed two robots, one is lightweight and suitable for taps and gestures, while the other is capable of multiple types of feedback. We presented a design space based on our implementations and conducted two evaluations. Since taps are versatile, easy to deliver and largely unexplored, our first evaluation focused on distinguishability of tap strengths and locations on the front and back torso. Participants had highest accuracy in distinguishing feedback on the uppermost regions and had superior overall accuracy in distinguishing feedback strengths over locations. Our second user study investigated HapticSnakes’ ability to deliver multiple feedback types within VR experiences, as well as users’ impressions of wearing our robots and receiving novel feedback in VR. The results indicate that participants had distinct preferences for feedbacks and were in favor of using our robots throughout. Based on the results of our evaluations, we extract design considerations and discuss research challenges and opportunities for developing multi-haptic feedback robots.
New electrocatalysts have become of increasing significance due to the need for inexpensive and effective catalysis in energy generating, converting and storage devices. Intrinsically conducting polymers such as PEDOT have recently been shown to provide an important new family of electrocatalytic materials. Studies thus far have demonstrated effective electrocatalysis in a range of contexts including for example in the iodine/iodide reaction and other similar reactions important in the dye sensitised solar cell, the oxygen reduction reaction fundamental to the fuel cell and metal–air batteries, and proton reduction in water to produce hydrogen. A general catalytic behaviour seems to be emerging in these studies. This article surveys recent progress in this field from our laboratories and others and foreshadows important new areas requiring study.
Micro/nano-structured SnS2 was prepared by a hydrothermal method using biomolecular l-cysteine and SnCl4·5H2O as sulfur source and tin source, respectively. The electrochemical performances of SnS2 electrodes were investigated using water-soluble binders of carboxymethyl chitosan (C-chitosan) and chitosan lactate, and compared with the conventional water-soluble sodium carboxymethyl cellulose (CMC) and non-aqueous polyvinylidene difluoride (PVDF). SnS2 electrode using the water-soluble binders (C-chitosan, chitosan lactate, and CMC) showed higher initial coulombic efficiency, larger reversible capacity, and better rate capabilities than that of PVDF. In addition, SnS2 electrode using C-chitosan binder exhibited somewhat worse cycling stability, but better rate capability at a high rate of 5C than CMC.
Rehabilitation for isolated forms of dystonia, such as cervical or focal hand dystonia, is usually targeted towards the affected body part and focuses on sensorimotor control and motor retraining of affected muscles. Recent evidence, has revealed people who live with dystonia experience a range of functional and non-motor deficits that reduce engagement in daily activities and health-related quality of life, which should be addressed with therapeutic interventions. These findings support the need for a holistic approach to the rehabilitation of dystonia, where assessment and treatments involve non-motor signs and symptoms, and not just the dystonic body part. Most studies have investigated Cervical Dystonia, and in this population, it is evident there is reduced postural control and walking speed, high fear of falling and actual falls, visual compensation for the impaired neck posture, and a myriad of non-motor symptoms including pain, fatigue, sleep disorders and anxiety and depression. In other populations of dystonia, there is also emerging evidence of falls and reduced vision-related quality of life, along with the inability to participate in physical activity due to worsening of dystonic symptoms during or after exercise. A holistic approach to dystonia would support the management of a wide range of symptoms and signs, that if properly addressed could meaningfully reduce disability and improve quality of life in people living with dystonia.
Sodium-ion batteries have emerged as a potential alternate battery chemistry to lithium ion batteries. In this paper, NaNi0.8Co0.15Al0.05O2 (Na-NCA) materials with hexagonal O3 or monoclinic O′3 structure were synthesized by either quenching or slow cooling after heating the precursors. Oxygen vacancies present during the cooling process were found to be the reason for structural differences. Quenched O3-type material has a lower concentration of Jahn-Teller active Ni3+, leading to the formation of high symmetry space group R 3 ¯ m . Both materials show better electrochemical performance than NaNiO2. In situ and Ex situ XRD were used to study the structure transitions of both materials during cycling. The structure change during cycling was found to be more reversible for quenched O3-type materials. It is anticipated that this study offers a new strategy for the development of sodium ion battery cathode materials.
Mankind has harnessed energy from water for thousands of years, but mainly in the form of hydropower. Recently, power generation from water-electrode interactions has been demonstrated and graphene-based materials have shown great potential in developing self-powered devices driven by power from graphene-water interactions. The current paper starts from introducing fundamental mechanisms of graphene-water interactions and then summarizes most recent advances in building self-powered systems based on these interactions. A perspective on current problems and future development trend in electricity generation from graphene-water interactions is also presented.
TiO2(B) anode for lithium-ion batteries is prepared by the hydrothermal method. The styrene butadiene rubber and sodium carboxyl methyl cellulose (SBR/CMC) and polyvinylidene fluoride (PVDF) binders are used to prepare the TiO2(B) electrodes. Scanning electron microscope and electrochemical impedance spectroscopy show that the electrode prepared with SBR/CMC has better electrode maintainability and electrochemical kinetics which result in better electrochemical performance. The optimized SBR/CMC binder content is proposed to be in the range of 12–15 wt%. In addition, the 1 M LiPF6 electrolyte dissolved in EC:DMC = 3:7 is more suitable for the TiO2(B) electrode. Using this suggested binder content and electrolyte, the TiO2(B) material exhibits superior capacity retention and rate capability. Even at the 10 C rate, the material still shows a discharge capacity of 142.5 mAh g−1 which keeps very well after 800 cycles. Based on this work, it is concluded that SBR/CMC is a promising binder for the TiO2(B) anode which provides not only better electrochemical performance but also more cheaper and environmental friendly than PVDF.
Lithium titanate oxide (Li4Ti5O12, LTO) is receiving significant attention as an alternative to graphitic anode due to high structural and thermal stability, and reduced possibility of formation of SEI film. In this study, Li4Ti5O12 is synthesized by the solid-state method and its electrochemical characteristics are examined by cyclic voltammetry and galvanostatic charge-discharge techniques. Moreover, we demonstrate the first instance of a numerical model used to understand the role of cell parameters in Li-LTO half-cells. The simulated charge-discharge capacity curves at 0.5, 1.0 and 1.5 C currents are in good agreement with experimental findings. Using this model, the effect of particle size, lithium diffusivity and electrode thickness on the charge-discharge capacity of Li-LTO cells have been investigated. Simulations show that the cell capacity is highly dependent on lithium transport in the solid matrix specifically at high current. Critical analysis of lithium concentration inside the solid matrix reveals a poor utilization of lithium storage sites and lower cyclable lithium in case larger particles and lower lithium diffusivity. The rise in the thickness of electrode leads to the lower achievable specific capacity of the battery due to increased cell overpotential and transport limitations for Li-ions and electrons.
We are rapidly approaching an inflection point in the adoption of electric vehicles on the roads. All major automotive companies are having well-funded plans for mass market affordable branded EV product line models, which can open the floodgates. A rapid growth of battery energy density, accompanied by an aggressive progress of reduction of costs of lithium-ion batteries, brings safety concerns. While more energy stored in the battery pack of an EV translates to a longer range, the downside is that accidents will be more violent due to battery inevitable explosion. With today's technology, severe crashes involving intrusion into the battery pack will potentially result in a thermal runaway, fire, and explosion. Most of research on lithium-ion batteries have been concerned with the electrochemistry of cells. However, in most cases failure and thermal runaway is caused by mechanical loading due to crash events. There is a growing need to summarize the already published results on mechanical loading and response of batteries and offer a critical evaluation of work in progress. The objective of this paper is to present such review with a discussion of many outstanding issues and outline of a roadmap for future research.
The polysulfide shuttle effect and lithium dendrite growth in lithium-sulfur (Li-S) batteries can repeatedly breach the anodic solid electrolyte interphase (SEI) over cycling. As a result, irreversible short-chain sulfide side products (Li2Sx, x = 1, 2) keep depositing on the Li anode, leading to the active material loss, increasing the Li+ transport resistance, and thereby reducing the cycle life. In this work, indium iodide (InI3) is investigated as a bifunctional electrolyte additive for Li-S batteries to protect the Li anode and decompose the side products spontaneously. On the one hand, Indium (In) is electrodeposited onto the Li anode prior to Li plating during the initial charging process, forming a chemically and mechanically stable SEI to prevent the Li anode from reacting with soluble polysulfide species to form Li2Sx (x = 1, 2) side products. On the other hand, by adequately overcharging the battery, the triiodide/iodide redox mediator is capable of chemically transforming side products deposited on the Li anode and separator into soluble polysulfides, which can be recycled by the cathode. It is shown that the battery with the InI3 additive exhibits a prolonged cycle life, and is capable of retrieving its capacity by a facile overcharging process.
Two heavy metals, Cd and Ni, have been separately recovered from spent AA-size Ni–Cd batteries by the potentiostatic electrodeposition and chemical precipitation methods, respectively. Various types and concentrations of HCl, H2SO4, and HNO3 acids had been used as leach extractants. Experimental results indicate that the acid with the best leach capability is 4M HCl. Three complexing reagents of NH3, sodium acetate, sodium citrate have been chosen and tested. The most effective buffer is sodium citrate. The optimum mole ratio of metallic ion to citrate ion is 1:1. The recovery process for Cd metal is conducted by the potentiostatic electrodeposition in a leach electrolyte with a sodium citrate complex. The optimum applied potential for Cd recovery is in the range −1100 to −1120mV (versus saturated calomel electrode (SCE)). The current efficiency for the recovery process is between 70 and 90% and depends strongly on the process parameters, e.g. liquor, concentration, applied potential, temperature, type of complex reagents, mole ratio, mass-transfer rate.
In this study, a solution method was employed to synthesize LiFePO4-based powders with Li3PO4 and Fe2P additives. The composition, crystalline structure, and morphology of the synthesized powders were investigated by using ICP-OES, XRD, TEM, and SEM, respectively. The electrochemical properties of the powders were investigated with cyclic voltammetric and capacity retention studies. The capacity retention studies were carried out with LiFePO4/Li cells and LiFePO4/MCMB cells comprised LiFePO4-based materials prepared at various temperatures from a stoichiometric precursor. Among all of the synthesized powders, the samples synthesized at 750 and 775°C demonstrate the most promising cycling performance with C/10, C/5, C/2, and 1C rates. The sample synthesized at 775°C shows initial discharge capacity of 155mAhg−1 at 30°C with C/10 rate. From the results of the cycling performance of LiFePO4/MCMB cells, it is found that 800°C sample exhibited higher polarization growth rate than 700°C sample, though it shows lower capacity fading rate than 700°C sample. For Fe2P containing samples, the diffusion coefficient of Li+ ion increases with increasing amount of Fe2P, however, the sample synthesized at 900°C shows much lower Li+ ion diffusion coefficient due to the hindrance of Fe2P layer on the surface of LiFePO4 particles.
Liquid nitrogen was used as a coolant in the freeze-drying method to synthesize nano-Li3V2(PO4)3/reduced graphene oxide (LVPGN) for the first time. In this material, reduced graphene oxide (rGO) (6.6 wt% in content) formed a 3D-framework and Li3V2(PO4)3 nanoparticles (30–150 nm) were strongly adhered to the surface of the rGO and enwrapped into the rGO sheets uniformly. The LVP nanoparticles can decrease the lithium ion diffusion length and the rGO can effectively improve the electronic conductivity. The material shows great rate performance with a capacity of 105.7 mAh g−1 at 20C for 3.0–4.3 V, and a good cycling performance with a discharge capacity of 123.2 mAh g−1 (96.7% of the first discharge capacity 127.4 mAh g−1) after 100 cycles at 0.1C.
Ternary, layer-type, transition metal phosphosulphide, PdPS, is synthesized by vapour transport method and used as battery electrode for lithium-ion battery. The performance of the electrode in bulk form is enhanced when it is made into a composite with reduced graphene oxide (rGO). The specific capacity, capacity retention and cycling behaviour at different current densities have been investigated. Relatively stable capacities of ∼350 mAh g−1 at a current density of 25 mA g−1 and ∼200 mAh g−1 at 100 mA g−1 are observed. The composite electrode is found to be active for sodium-ion battery as well.
The most serious drawback of aluminium-air batteries with aqueous alkaline electrolytes is parasitical hydrogen evolution reaction. It is essential to identify an effective electrolyte additive for suppressing the self-corrosion of the aluminium anode. This work reports the inhibition effects of three quaternary ammonium-type surfactants, cetyl trimethyl ammonium bromide (CTAB), dihexadecyl dimethyl ammonium bromide (DDAB) and dodecyl dimethyl benzyl ammonium bromide (DDBAB), as corrosion inhibitors for the aluminium-air battery anode in 4 mol L−1 NaOH solution. Hydrogen collection technique, potentiodynamic polarization, electrochemical impedance and surface analysis are used to evaluate the corrosion inhibition properties of the additives. The results indicate that all the additives show anticorrosion efficiency in the order of DDBAB > CTAB > DDAB. The molecular structures of the surfactants are simulated by the density functional theory method in order to clarify the correlation between inhibition effect and the molecular structures. The presence of surfactants not only increases the voltage of the aluminium-air battery under galvanostatic discharge, but also increases the specific capacity markedly. Finally, the inhibition mechanism of cationic surfactants is proposed, and the reasons for the different inhibition performance of these additives are analysed.
TiO2 nanorod/graphene oxide (TiO2 nanorod/GO) composites with different TiO2/GO weight ratios were successfully prepared by self-assembly of GO and ready-made TiO2 nanorods under room temperature conditions. TiO2 nanorods were synthesized via the hydrothermal method, and GO was obtained via a modified Hummers method. X-ray diffraction, atomic force microscopy, and high-resolution transmission electron microscopy indicated that rutile TiO2 nanorods were loaded on the GO nanosheet without obvious aggregation. The electrochemical performance of the TiO2 nanorod/GO composites was confirmed by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy in 1molL−1 Na2SO4 aqueous electrolyte. The ratio of TiO2 nanorods to GO in composite materials has significant influence on electrochemical performance of composite electrodes. TiO2 nanorod/GO composites with 4.00wt.% GO have excellent electrochemical performance. The maximum specific capacitance of this composite electrode was 100Fg−1 at 5mVs−1 scan rate. The TiO2 nanorod/GO composites also exhibited good electrochemical stability with a capacitance degradation of less than 20% over 3000 cycles. The electrochemical performance of the as-prepared nanocomposites could be enhanced by increasing chemical interactions between TiO2 and GO.
A 3D graphene sheet–carbon nanotube (GS–CNT) structure with a good wetting property, high porosity, and large surface area is homogeneously deposited with active amorphous manganese oxide (a-MnO x ) by potentiodynamic deposition. The flowery a-MnO x nanostructure with ultra-slender petals (ca. 5–8 nm) on the framework of hierarchically porous GS–CNT matrix not only enables nearly full utilization of a-MnO x but also retains sufficient conductivity and porosity for the high-rate charge–discharge application. The use of a-MnO x on the 3D GS–CNT material produces a specific capacitance of MnO x of 1200 F g−1 which is much-higher than that of a pure a-MnO x electrode (C S,Mn = 233 F g−1). The specific energy and specific power of a-MnO x /GS–CNT are respectively as high as 46.2 Wh kg−1 and 33.2 kW kg−1, revealing that our work conceptually provides a way to produce porous structures composed of graphene, carbon nanotubes, and various electroactive materials for high-performance energy storage devices.
In this study, carbonaceous materials such as activated carbon and activated carbon aerogel were chemically modified with a surfactant sodium oleate in order to improve their specific capacitance and energy storage in electrochemical double-layer capacitors (EDLCs). Optimal conditions for surface modification of activated carbon have been examined as a surfactant solution concentration of 0.25wt.% together with a time of 24h for treatment at 25°C. Specific capacitance and energy density can be improved significantly by surface modification of carbon materials. The enhancement in specific capacitance and energy density is mainly attributable to improvement in wettability of carbon materials, which results in a higher usable surface area and a smaller internal resistance. The effects from surface modification become more marked at higher discharge rates, at which the internal resistance has a more important impact on the energy delivery. A two times energy density of the original carbon could be achieved for the modified carbon materials at a high discharge rate, which indicates that the modified carbons are more suitable in EDLCs for high current applications. In addition, the modified carbon materials possess excellent cycle stability (the capacity decay was only 4% after 20,000 cycles).