batterydata/paper-abstracts huggingface dataset:
This work aims to study the reasons for the rapid capacity fading in the field of lithium-sulphur batteries. It is found that the formation of non-soluble and insulating lithium sulphide, Li2S, upon sulphur reduction is one of the main reasons to account for the capacity fade due to its relatively low electrochemical activity and blocking of the carbon framework. A variety of analytical techniques are used to assess the formation of Li2S and visualize the resulting morphological changes in a mesoporous carbon/sulphur composite (MCS) during battery operation. It is shown that simply changing the cut-off voltages can alter retention and resistance of the cells during cycling. Since the electrochemical activity of lithium polysulphides decreases with the order, elimination of low order of polysulphides is considered critical. Thus, in order to oxidize the least sulphur reduction specie, Li2S, two different additives are suggested; namely an electrolyte additive, LiI, or an electrode additive, V2O5. Incorporation of the one of these components into the MCS composite enables the delivery of higher capacities (i.e. as compared to a bare C/S composite). The increased capacity is linked not only to the co-cathode materials, which contribute to the total capacity, but also to the oxidizing agent and internal redox mediator role of the additives.
We report N-(triphenylphosphoranylidene) aniline (TPPA) as a new electrolyte additive for high performance lithium cobalt oxide (LiCoO2) electrodes during high voltage operations. When cycled in the voltage range of 3.0–4.4V, graphite-LiCoO2 full cells with 0.2wt% TPPA exhibited 10% increased discharge capacities after 200 cycles compared to those of control cells with no such additive. The enhanced cycling performance is attributed to the additive effect toward the modified surface films on LiCoO2 electrodes that suppress the decomposition of both solvent and salt in the electrolyte. This additive effect was characterized by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS).
Quasi-solid-state electrolytes (QSEs), consisting of pseudo-ternary system, i.e., room temperature ionic liquid (RTIL)-lithium bis(trifluoromethanesulfonyl)amide (Li-TFSA)-fumed silica nano particles, were prepared for use as electrolytes in bulk-type all-solid-state cell configuration lithium-sulfur rechargeable batteries. Regardless of the high concentration of RTIL-Li-salt mixtures with fumed silica nano particles, i.e., 80-90% volume ratio, the composites were white powders. Further blending with 5wt% polytetrafluoroethylene (PTFE) powder caused the composite powders to become transparent sheets of 30-200 μm in thickness. The electrolyte sheets exhibited liquid-like high apparent conductivities regardless of their solid-like appearance. Sulfur utilization ratios were enhanced using conductive additives with high specific surface areas. Cells with notable performance were successfully assembled after the optimization of the RTIL solvent composition, electrolyte thickness, and conductive additive species. The initial discharge capacity was 1100mAh g−1 at 0.05 C. After 45 discharge-charge cycles, the discharge capacity was still 690mAhg−1. This performance is comparable to lithium-sulfur cells that use the RTIL-Li-salt liquid electrolytes.
Electrochemical performance of the 18650 lithium-ion batteries consisting lithium-rich layered oxides 0.5Li2MnO3·0.5LiMn0.33Ni0.33Co0.33O2 cathode material and soft carbon anode is investigated in detail. The cathode is synthesized by a spray drying process and the properties are studied by various methods, while the soft carbon is commercial available. The assembled batteries can exhibit excellent cyclic performance with a capacity retention of 90.2% even after 600 cycles in the voltage ranges of 2.0-4.5V (at 1C-rate). Moreover, they can also deliver excellent rate capabilities as the discharge capacity under 40C is nearly equal to 83.9% of that under 1C (voltage range is in 2.0-4.5V). Furthermore, in order to evaluate the mechanism of the superior performance exhibited by the full cells, cells after 300 cycles are disassembled in a glove box to assess the changes on the active materials by using a series of technique methods, including a scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), High-resolution transmission electron microscope (TEM) and selected area electron diffraction (SAED).
ABSTRACT Monodisperse porous Ni0.5Zn0.5Fe2O4 nanospheres have been successfully synthesized by the solvothermal method. The diameter of the nanospheres can be tuned by controlling the reactant concentration. Lower reactant concentration is favoured for the synthesis of mesoporous Ni0.5Zn0.5Fe2O4 nanospheres with higher surface area. The electrochemical results show that mesoporous Ni0.5Zn0.5Fe2O4 nanospheres exhibit high reversible specific capacity (1110 mAh g−1) for Li storage and high capacity retention, with 700 mAh g−1 retained up to 50 cycles. The excellent electrochemical properties could be attributed to the large surface area and mesoporous structure. The results suggest that Ni0.5Zn0.5Fe2O4 could be a promising high capacity anode material for lithium ion batteries.
This paper presents the use of Li4Ti5O12 (LTO) as anode with ionic liquid gel polymer electrolyte (IL-GPE) for application in lithium ion batteries. IL-GPE was obtained by in situ photopolymerization method of a mixture of ethoxylated bisphenol A diacrylate (bis(AEA4) and 0.4 M solution of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (MPPipTFSI). The surface morphology of the IL-GPE was studied using scanning electron microscopy (SEM). Stable, porous and flexible gel polymer electrolyte characterized high ionic conductivity (0.64 mS cm−1 at 25 °C) and a wide electrochemical stability window (ESW) (4.8 V). The performances of LTO/IL-GPE/Li cell were tested by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge. Good charge/discharge capacities and low capacity loss at medium C rates preliminary cycling was obtained.
One of the major issues in time-critical medical applications using wireless technology is the size of the payload packet, which is generally designed to be very small to improve the transmission process. Using small packets to transmit continuous ECG data is still costly. Thus, data compression is commonly used to reduce the huge amount of ECG data transmitted through telecardiology devices. In this paper, a new ECG compression scheme is introduced to ensure that the compressed ECG segments fit into the available limited payload packets, while maintaining a fixed CR to preserve the diagnostic information. The scheme automatically divides the ECG block into segments, while maintaining other compression parameters fixed. This scheme adopts discrete wavelet transform (DWT) method to decompose the ECG data, bit-field preserving (BFP) method to preserve the quality of the DWT coefficients, and a modified running-length encoding (RLE) scheme to encode the coefficients. The proposed dynamic compression scheme showed promising results with a percentage packet reduction (PR) of about 85.39% at low percentage root-mean square difference (PRD) values, less than 1%. ECG records from MIT-BIH Arrhythmia Database were used to test the proposed method. The simulation results showed promising performance that satisfies the needs of portable telecardiology systems, like the limited payload size and low power consumption.
Thin films of LiNi0.5Mn1.5O4 (LNMO) were prepared on gold-coated stainless steel substrates via a poly(vinylpyrrolidone)-based sol-gel process. Films with a thickness in the range of 1μm were found to exhibit a capacity close to the theoretical one. The formation of interlayers (i) between the LNMO films and the LP30 electrolyte (mixture of dimethyl carbonate (DMC) and ethylene carbonate (EC) (1:1 v/v) containing 1 mol·l−1LiPF6) and (ii) between the LNMO films and the gold-coated substrate was studied by means of electrochemical impedance spectroscopy (EIS), time-of-flight secondary-ion mass-spectrometry (ToF-SIMS), and scanning transmission electron microscopy together with energy dispersive X-ray spectroscopy (STEM/EDX). The combination of these methods turns out to be very powerful for understanding the chemical composition and properties of interlayers and for identifying the origin of semicircles in Nyquist impedance plots. At the LNMO/LP30 interface, we observe an interlayer (solid electrolyte interface, SEI) with a thickness of about 50 nm, while at the LNMO/gold interface, a mixed oxide layer with a thickness in the range of 250nm is found. The mixed oxide layer is caused by diffusion of Cr and Ni from the stainless steel through the gold layer. While the LNMO/LP30 interlayer contributes significantly to the interfacial impedance, the impedance of the LNMO/gold interlayer seems to be negligible, despite its larger thickness.
Triboelectric nanogenerator collects kinetic energy from human activities and endows sustainable operation of wearable electronics. This work reports a very natural design of triboelectric nanogenerator for harvesting low-frequency walking energy. In the protocol, the human body and ground serve as electrodes of the triboelectric system, which helps the rubber soles to collect mechanical energy during walking motion of humans and produce pulsed alternative currents. The average open-circuit voltage and short-circuit current produced by the system at low frequency are about 400V and 12μA, respectively. Considering the very simple structure, this natural triboelectric nanogenerator can be easily integrated into wearable electronics and take full advantage of human motions as power source and as self-powered systems.
Biofuel cells implanted in living clams and producing sustainable electrical power in vivo were integrated in batteries. The “electrified” clams, being biotechnological living “devices”, were able to generate electrical power using physiologically produced glucose as the fuel. The activity of the living batteries was dependent on the environmental conditions which are affecting physiological processes in clams. The living batteries generated open circuitry voltage (Voc), short circuitry current (Isc) and maximum power (Pmax) of ca. 800 mV, 25 μA, 5.2 μW and ca. 360 mV, 300 μA, 37 μW for the serial and parallel connections of 3 “electrified” clams, respectively. A clam-battery was connected to a capacitor which was charged up to 240 mV providing accumulation of electrical energy up to 28.8 mJ. Discharging the capacitor on an electrical motor resulted in the motor rotation. The “electrified” clams integrated in batteries demonstrated the possibility of activating electrical/electronic devices using energy produced in vivo.
A spherical carbon material of meso-carbon microbead (MCMB) was examined as an anode in a polyethylene oxide (PEO) based polymer electrolyte lithium battery. The electrochemical performance of the carbon electrode with the polymer electrolyte depended on the electrode thickness and the particle size of MCMB. The 30μm-thick electrode of MCMB with the particle size of 20–30μm showed a reversible capacity comparable with that in a liquid electrolyte, but the 100μm-thick electrode showed a half of the 30μm-thick electrode. The smaller particle size of 5–8μm exhibited a high irreversible capacity at the first charge–discharge cycle. The reaction heat between MCMB and the polymer electrolyte was 0.5JmAh−1, which was much lower compared to those between lithium metal and the polymer electrolyte, 1.2JmAh−1, and MCMB and conventional liquid electrolyte, 4.3JmAh−1.
We assessed major cognitive domains in symptom-free children of patients with schizophrenia compared to the healthy children of parents with no psychopathology using neurocognitive tests. We hypothesized that, offspring at high-risk for schizophrenia would have significant impairment in major domains: attention, memory, verbal–linguistic ability and executive functions. Thirty symptom-free children (17-males, 13-females; intelligence quotient=99.6±13.6; age=12.69±2.32 and education=5.8±2.3 years) having a parent diagnosed with schizophrenia and 37 healthy children matched for gender (19-males, 18-females), IQ (106.05±14.70), age (12.48±2.58) and years of education (6.0±2.5) were evaluated. The study group showed significant poor performance in cognitive domains, such as working memory (assessed with Auditory consonant trigram test), focused attention (Stroop test), attention speed (Trail making test), divided attention (Auditory consonant trigram test), executive functions (Wisconsin card sorting test), verbal fluency (Controlled word association test) and declarative memory (Rey verbal learning and Short-term memory test). However, no group differences were detected either on verbal attention (Digit span forward test) or sustained attention (TOVA, a continuous performance task); the latter as consistently reported to be a predictor of schizophrenia. In order to determine the cognitive endophenotype of schizophrenia, it seems more rational to conduct comprehensive evaluation of neurocognitive domains in well-matched groups via using sufficiently challenging tests to detect slight deficits. In addition, longitudinal studies with a larger sample size evaluating neurocognitive functions combined with genetic analysis may provide clues about explaining the genetic background of the disorder within the endophenocognitype concept and serve as new targets for early interventions.
The oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) of multi-electron transfer are footstone and crucial reactions for energy conversion and storage technologies. The catalysts play the important roles in both ORR and OER. It is particularly desirable but difficult to use cheap raw materials and facile way to prepare non-noble metal bifunctional electrocatalysts with high activity and stability for both ORR and OER. Here, a simple and effective method is reported for synthesizing cobalt sulfide (Co9S8)-porous carbon spheres composite catalyst (Co9S8/CS) with thiourea, glucose and cobalt nitrate. The material structures of N, S co-doped carbon combined with Co9S8 have been evidenced by high-resolution transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. Under the thermal treatment temperature of 800 °C, the prepared catalyst exhibits an analogous oxygen reduction dynamics behavior to the commercial platinum catalyst with a four-electron pathway, and a superior oxygen evolution performance with the small reversible potential gap of 0.78 V (ΔE = E j=10 – E1/2) to most of the bifunctional electrocatalysts reported to date, such as metal-free carbon hybrids and transition metal doped carbon materials. Due to the interaction between Co9S8 and N, S co-doping carbon, Co9S8/CS-800 exhibits exceptionally good durability and excellent activity compared with the commercial Pt/C for ORR and OER, predicting a promising application in metal-air batteries and fuel cells.
Electrochemically active lithium sulfide–carbon (Li2S–C) composite positive electrodes, applicable for rechargeable lithium-ion batteries, were prepared using spark-plasma-sintering (SPS) process. The electrochemical tests demonstrated that the SPS-treated Li2S–C composites showed the initial charge and discharge capacities of ca. 1200 and 200mAhg−1, respectively, though Li2S has been reported to show no significant charge capacities when conventionally mixed with carbon powder. Such activation of Li2S was attributed principally to strong bindings between Li2S and carbon powders, formed by the SPS treatment. The ex situ XRD measurements showed that some amounts of Li2S were still remained unchanged and any elemental sulfur was not detected even at fully charged state, which was similar to Li/S cells.
An in-situ generated carbon matrix has demonstrated to be essential to provide electrical conducting properties to Na3V2(PO4)3 as cathode materials for sodium-ion cells. Na3V2(PO4)3/C nanocomposites are synthesized by varying their eventual carbon content in order to determine the influence in the electrochemical behavior. X-ray diffraction patterns evidence the crystallinity and purity of Na3V2(PO4)3, while Raman spectroscopy reveals the disordered character of the carbon phase. The determination of the chemical state of the carbonaceous phase unveils that an increase of the carbon content involves a decrease of carboxyl groups and a slight increase of graphitic carbon atoms, in agreement with the Raman results. The electrochemical characterization of these composites in sodium half cells reveals that carbon contents close to 7% are preferred to provide cycling stability, while the best rate performance is achieved for the sample with carbon content close to 11%. A full sodium-ion cell delivers an energy density of 320Whkg−1 at 2C.
Safety is the first priority in lithium ion (Li-ion) battery applications. A large portion of electrical and thermal hazards caused by Li-ion battery is associated with short circuit. In this paper, both external and internal short circuit tests are conducted. Li-ion batteries and battery packs of different capacities are used. The results indicate that external short circuit is worse for smaller size batteries due to their higher internal resistances, and this type of short can be well managed by assembling fuses. In internal short circuit tests, higher chance of failure is found on larger capacity batteries. A modified electrochemical–thermal model is proposed, which incorporates an additional heat source from nail site and proves to be successful in depicting temperature changes in batteries. Specifically, the model is able to estimate the occurrence and approximate start time of thermal runaway. Furthermore, the effectiveness of a hydrogel based thermal management system in suppressing thermal abuse and preventing thermal runaway propagation is verified through the external and internal short tests on batteries and battery packs.
The aim of the current review was to provide a new, in-depth insight into possible pharmacological targets of amantadine to pave the way to extending its therapeutic use to further indications beyond Parkinson’s disease symptoms and viral infections. Considering amantadine’s affinities in vitro and the expected concentration at targets at therapeutic doses in humans, the following primary targets seem to be most plausible: aromatic amino acids decarboxylase, glial-cell derived neurotrophic factor, sigma-1 receptors, phosphodiesterases, and nicotinic receptors. Further three targets could play a role to a lesser extent: NMDA receptors, 5-HT3 receptors, and potassium channels. Based on published clinical studies, traumatic brain injury, fatigue [e.g., in multiple sclerosis (MS)], and chorea in Huntington’s disease should be regarded potential, encouraging indications. Preclinical investigations suggest amantadine’s therapeutic potential in several further indications such as: depression, recovery after spinal cord injury, neuroprotection in MS, and cutaneous pain. Query in the database http://www.clinicaltrials.gov reveals research interest in several further indications: cancer, autism, cocaine abuse, MS, diabetes, attention deficit-hyperactivity disorder, obesity, and schizophrenia.
A thermally durable all-solid-state lithium ion battery composed of a complex hydride, oxide electrolytes, and LiNi1/3Mn1/3Co1/3O2 active material is developed. This battery exhibits a discharge capacity of 56 mAh g−1, and the tenth capacity retention ratio is 29% at 150 °C owing to the large contact resistance between the electrolyte layer and the composite positive electrode layer. This large contact resistance is reduced by introducing an adhesive layer comprised of a mixture of LiBH4 and LiNH2 that is easily melted by thermal treatment and fills the voids and pores at the interface between the two layers. As a result, repeated charge-discharge cycles are successfully demonstrated at 150 °C with a high discharge capacity and discharge capacity retention ratio. The first discharge capacity is enhanced to 114 mAh g−1 and the capacity retention ratio at the tenth cycle is improved to 71%. These results demonstrate that using an adhesive layer is an effective measure to reduce the contact resistance and thereby enhance the performance of the battery.
The influence of the precursors, namely potassium ferrocyanide and potassium ferricyanide on the particles sizes of Prussian Blue (PB) and Prussian Green (PG), under identical reaction conditions have been investigated. It was found that the particle sizes influence the gravimetric capacity utilization of these materials as cathodes for aqueous potassium (K+) ion batteries. The PG particle sizes were on the order of 50–75nm, whereas PB particles size were on the order of 2–10 microns. The PG cathodes demonstrated a reversible capacity of 121.4mAhr/g, with a coulombic efficiency of 98.7% compared to PB cathodes which demonstrated 53.8mAhr/g, with a coulombic efficiency of 100%. We interpret the increased capacity of PG batteries relative to PB batteries as being a result of the smaller particle size of PG, which results in greater accessibility of the cathode to K+ ions.
A new start in development of the alkaline methanol/air system was made at the Graz University of Technology. A comparison between the metal/air system and the methanol/air system, some new work on the electrodes for the methanol/air system and silver as catalyst for oxygen reduction is given in this paper.
This work emphasizes the structural, morphological, electrical, and electrochemical properties of 0.05 mol Zr- and Si-doped Li4Ti5O12 synthesized using the molten salt method and applied to negative electrodes in Li-ion batteries. Formation of the spinel phase with face-centered cubic structure in the nominally pure and Zr- and Si-doped samples are revealed from X-ray powder diffraction technique. Lattice parameters refined by full-profile Rietveld method are in accordance with the literature data for the Li4Ti5O12 (Li1.333Ti1.667O4) spinel structure. The presence of possible functional groups is identified using Fourier transform infra red spectroscopy. The field emission scanning electron microscopic images indicate the formation of micron-sized (1.5–2 μm) randomly distributed polyhedral-shaped particles. The electrical conductivity studies demonstrate the grain-conducting behavior of the material. The maximum DC conductivity of 2 × 10−5 S cm−1 is observed for Zr-doped Li4Ti5O12 at room temperature. The galvanostatic charge–discharge studies show that Zr-doped Li4Ti5O12 exhibits a high discharge capacity of about 325 mAh g−1 at 0.01 °C, higher than Si-doped Li4Ti5O12 (200 mAh g−1), and also that the cycling stability of Zr-doped Li4Ti5O12 is enhanced.
Boron-doped Ketjenblack is attempted as cathode catalyst for non-aqueous rechargeable Li–O2 batteries. The boron-doped Ketjenblack delivers an extremely high discharge capacity of 7193 mAh/g at a current density of 0.1 mA/cm2, and the capacity is about 2.3 times as that of the pristine KB. When the batteries are cycled with different restricted capacity, the boron-doped Ketjenblack based cathodes exhibits higher discharge platform and longer cycle life than Ketjenblack based cathodes. Additionally, the boron-doped Ketjenblack also shows a superior electrocatalytic activity for oxygen reduction in 0.1 mol/L KOH aqueous solution. The improvement in catalytic activity results from the defects and activation sites introduced by boron doping.