batterydata/paper-abstracts huggingface dataset:
A fast charging/discharging capability in electrode materials is one of the essential properties of Li-ion batteries. A well-known approach for improving the kinetics of electrode materials is minimization of the particle size to the nanoscale, especially for phase separating materials such as LiFePO4 and Li4Ti5O12. Here, we report on ultrafast kinetics in a phase separating material with submicron particles enabled by the formation of an intermediate phase during discharge even without minimizing the particle size. The intermediate phase during (dis)charging acts as a structural buffer between the Li-rich and Li-poor phases, leading to reduced mechanical stress/strain on the interface in a particle, which can suppress structural defects, and a substantial reduction in the phase transformation barrier, which can make the electrochemical reaction of particles in the electrode homogenous. As a result, the resulting phase separating material can deliver ∼70 mA h g−1 at a 200C discharge rate (18 s for full discharge) with a 1C charge rate, and prolonged cycling stability for 1000 cycles even though it has a wide particle size distribution from 50 nm to 600 nm with an average of ∼300 nm. This finding will provide a new avenue for achieving fast electrochemical kinetics with a high volumetric energy density in electrode materials for high performance Li-ion batteries.
The effect of electrode thickness and density for unpressed and pressed natural graphite electrodes were studied using electrochemical characterization. Pressing the graphite electrode decreased the reversible capacity and the irreversible capacity loss (ICL) during formation. As electrode density increased, the capacity retention at high rate increased until 0.9g/cm3, and then decreased. The cycle performances of the pressed graphite electrodes were more stable than the unpressed one. Pressing graphite electrode affected on its electrochemical characterization such as ICL, high rate cycling and cycle performance.
The specific capacity of lithium-ion battery with lithium cobalt oxide as cathode depends on the upper limitation voltage for charge/discharge cycling, but this oxide tends to be destructed structurally when it is cycled in carbonate-based electrolyte under high voltage. We report a novel electrolyte additive, fumaronitrile (FN, CNCHCHCN), which can maintain the structural integrity of lithium cobalt oxide. Electrochemical measurements indicate that lithium cobalt oxide exhibits poor cyclic stability when it is cycled under 4.5 V (vs. Li/Li+) and the charged cathode suffers serious self-discharge in a base electrolyte, 1.0 mol L−1 LiPF6 in EC/EMC/DEC (3:5:2, by weight). These issues can be overcome effectively by adding 0.5% FN into the base electrolyte. Physical and chemical characterizations demonstrate that the poor cyclic stability and self-discharge of lithium cobalt oxide result from its structural destruction caused by HF formed from electrolyte decomposition, and FN yields a protective cathode interphase film which maintains the structural integrity of lithium cobalt oxide.
Long non-coding RNAs (lncRNAs) homeobox (Hox) transcript antisense intergenic RNA (HOTAIR) and HOXA transcript at the distal tip (HOTTIP) have been suggested to be implicated in liver cancer tumorigenesis and progression; however, little is known about the role of the plasma HOTAIR and HOTTIP in liver cancer diagnosis and prognosis. The current study aimed at measuring the plasma levels of long non-coding RNAs (HOTAIR and HOTTIP) expression in chronic liver disease (CLD) due to HCV genotype 4 infection with/without cirrhosis and HCC patients in an attempt to evaluate the potential benefits of these new circulating as non-invasive diagnostic biomarkers and a novel therapeutic strategy for liver cirrhosis and carcinogenesis of Egyptian patients. Hundred subjects were included in this study, divided into two groups; group I (50 patients) were classified into subgroup Ia (CLD without cirrhosis, n = 25) and subgroup Ib (CLD with cirrhosis, n = 25), group II (CLD patients with HCC, n = 25), and control (healthy volunteer, n = 25). The expression of lncRNAs (HOTAIR and HOTTIP) genes was analyzed by real-time PCR.
To reduce the sintering temperature of spinel coatings to a safe temperature for Fe–Cr ferritic alloys, an MnCo2O4–MnO2 bicomponent coating has been prepared on SUS430 ferritic alloy by slurry coating, followed by air sintering at a temperature of 800 °C. The resultant coating is stable during cyclic oxidation tests and is effective at improving the oxidation resistance of SUS430 alloy. The area-specific resistance of coated samples remains nearly constant during long-term oxidation at 800 °C and is less than 6 mΩ cm2 even after oxidation for 1000 h. These results indicate that the low-temperature sintered MnCo2O4–MnO2 coating is a promising protective material for Fe–Cr ferrite alloys, especially SUS430, which are seriously oxidized at temperatures ≥850 °C.
There is a growing demand for hybrid supercapacitor systems to combine the advantages of both lithium-ion battery and supercapacitors for the application of electric vehicles. We describe in this paper one kind of hybrid supercapacitor comprising spherical Li4Ti5O12 as negative electrode and activated carbon (AC) as positive electrode in the non-aqueous electrolyte. The Li4Ti5O12 spheres were synthesized using a LiCl-KCl molten-salt method and TiO2 spheres as the template. The Li4Ti5O12 spheres revealed high discharge capacity (168 mAh g−1 at 0.2C), and a good capacity retention with high coulombic efficiency after cycling, which can be potential anode material for lithium ion batteries and negative material for hybrid supercapacitor. The AC//LTO hybrid supercapacitor exhibits excellent capacity retention of 93% after 500 cycles and offers higher energy density and power density than the AC//AC symmetric supercapacitor. The presented AC//LTO hybrid supercapacitor could be a competitive candidate for the promising energy storage devices.
Besides presenting the intrinsic characteristics of manganese dioxide electrode materials, the worldwide research progress in their preparation and application for electrochemical capacitor are introduced in this article. Moreover, the future development trend and prospects are discussed.
In situ neutron radiography (NR) was used to study the gas evolution on graphite electrodes in lithium-ion cells containing different PVDF-based gel-type electrolytes. The amount of gas bubbles and channels was calculated by image analysis. Gas production was extremely high in the case of the electrolyte containing ethylene carbonate (EC) and propylene carbonate (PC) (2:3, w/w), 1M LiClO4. About 60% of the electrode surface consisted of the gas phase which resulted in an inhomogeneous local current distribution. In contrast, the electrolyte containing EC and γ-butyrolactone (GBL) (1:1, w/w), 1M LiBF4 only showed a small increase of the gas volume between the electrodes of about 3%. In situ NR also revealed the displacement of the electrolyte due to gas evolution and volume changes of the electrodes.
α-Fe2O3 nanotubes and nanorods are obtained via a hydrothermal method without further annealing. Both of them are characterized by X-ray powder diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The lithium-storage performances of the nanostructures are measured and compared in terms of reversible capacity, cycling stability, and rate capability. The electrode based on the nanotubes delivers the reversible capacities of 1200 mAh g−1 at 100 mA g−1, 1000 mAh g−1 at 500 mA g−1, and 810 mAh g−1 at 1000 mA g−1 after 60 cycles, much higher than those based on the nanorods. The better performances of the nanotubes could be assigned to their tubular morphology that tolerates the huge volume change during the discharge/charge processes and possesses the large surface area to increase the contact between the electrode and the electrolyte. These insights will be of benefits in the design of other anode materials for lithium ion batteries.
Publisher Summary This chapter deals with the basic theory behind the operation of batteries. A galvanic or voltaic cell consists of two dissimilar electrodes immersed in a conducting material such as a liquid electrolyte or a fused salt; when the two electrodes are connected by a wire a current flows. Each electrode, in general, involves an electronic (metallic) and an ionic conductor in contact. At the surface of separation between the metal and the solution there exists a difference in electrical potential, called the electrode potential. The electromotive force (e.m.f.) of the cell is then equal to the algebraic sum of the two electrode potentials, appropriate allowance being made for the sign of each potential difference as follows. The electromotive force of a cell is defined as the potential difference between the poles when no current is flowing through the cell. The electromotive force of a cell is usually measured by the compensation method. Further, the chapter discusses the effects of couple materials, electrolyte composition, concentration, and temperature on battery performance, followed by the factors that affect the discharge rate on battery capacity.
In situ cross-linked corn starch is used as a binder in silicon (Si) composite anodes for enhancing the cycling stability of lithium-ion batteries. The corn starch binder is in situ cross-linked by maleic anhydride during the fabrication of Si anodes. The cross-linking reaction of corn starch is investigated by infrared spectroscopy, solid-state 13C nuclear magnetic resonance spectroscopy and thermal gravimetric analysis. The results show that the hydroxy groups of corn starch react with maleic anhydride to form ester linkages, which eventually form a three-dimensional network structure. The cross-linked corn starch binder significantly enhances the adhesion of the Si/conductive carbon composite on the copper current collector. Peeling test experiments show that the adhesion force of the cross-linked corn starch binder is 4.9 times higher than that of the corn starch binder without cross-linking. Moreover, the cell performance tests show that the Si composite cathode with the cross-linked corn starch binder exhibits a high specific capacity of 3720 mAh g−1 and enhances cycle-life performance. This in situ cross-linking approach underscores the potential of corn starch, which is a low-cost and environmentally sustainable material, as a binder for the Si composite electrodes to improve its electrochemical performance.
The direct effect of nitrogen content and various nitrogen species on oxygen reduction reaction (ORR) activities in non-aqueous lithium-oxygen (Li-O2) batteries are systematically investigated. Mesoporous carbon (MC) with various nitrogen species is prepared through heat treatment of N-containing precursor under different temperature. The effect of the heat treatment temperature on the performance of carbon materials in Li-O2 battery is investigated. The bonding state of nitrogen atoms is found to have a significant effect on the ORR activity. The ORR activity in Li-O2 battery is proved to be dependent on the quaternary N content while the total N content in the carbon material does not play a crucial role in the ORR process.
Based on a displacement reaction mechanism, Cu2Se is a good candidate for non-insertion-based cathode materials of rechargeable magnesium batteries. Nevertheless, its relatively low electronic conductivity leads to a poor rate capability and an unsatisfactory cycling performance. In this work, we firstly reported the improved electrochemical performance of Cu2Se cathode based on displacement reaction for Mg batteries triggered by a Li salt additive in a typical magnesium electrolyte 0.4 mol dm−3 (PhMgCl)2-AlCl3/THF. Cu2Se materials with different morphologies and particle sizes were synthesized by a solvothermal process and a hydrothermal method, respectively. Cu2Se with smaller particle sizes by the hydrothermal method exhibits a higher specific capacity (152.7 mAh g−1 first discharge capacity at 0.02 C) but poor cycling performance in 0.4 mol dm−3 (PhMgCl)2-AlCl3/THF electrolyte. LiCl was added in the magnesium electrolyte to promote the displacement reaction of the Cu2Se material. An initial discharge capacity of approximately 239.7 mAh g−1 with 48.4% capacity retention after 20 cycles at 0.1 C can be obtained for Cu2Se in 0.4 mol dm−3 (PhMgCl)2-AlCl3+1.0 mol dm−3 LiCl/THF electrolyte. Furthermore, the cycling performance and rate capability are enhanced by in situ homogeneously anchoring Cu2Se particles onto the surface of the reduced graphene oxide (rGO) nanosheets. Cu2Se/rGO composite with 10 wt% rGO exhibits 64.2% capacity retention after 20 cycles at 0.1 C, and a more than 120 mAh g−1 reversible capacity at 0.2 C in the hybrid Mg2+/Li+ electrolyte.
The commercialization of lithium sulfur batteries have so far hindered by the low electrochemical utilization and rapid capacity fading of sulfur cathode, which is induced by low electron conductivity and high dissolution of intermediate polysulfides. Recent studies have shown that the metal (Pt, Au, Ni) as electrocatalyst of lithium polysulfides and its metallic porous nanostructure can suppress the shuttle effect. In this work, we use the porous nanostructure of nickel fibers/sulfur as-designed composite cathode material for lithium sulfur batteries. The initial discharge capacity of the cathode with the added 3(%) nickel fibers was 805mAhg−1, and the remaining capacity was 440mAhg−1 after 50 cycles at 0.766mAcm−2. Even at a high current density of 1.532mAcm−2, it also kept a high discharge capacity of 310mAhg−1. Compared with pure sulfur electrodes, the electrodes containing nickel fibers showed an obviously improved cycle and rate performances, confirming that metallic porous nanostructure of nickel can not only contribute to reducing the dissolution of polysulfides into electrolytes, but also has a catalytic effect on the redox reactions during charge-discharge process.
Three dimensional (3D) hollow porous activated carbon was prepared by pyrolysis of lotus seedpod as biomass carbon precursor. Subsequently, manganese dioxide (MnO2) particles were in situ formed uniformly on the hollow pipes activated carbon by hydrothermal deposition reaction. The morphology and structure of the obtained lotus seedpod-based activated carbon/manganese dioxide composite (L-AC@MnO2) were investigated using the scanning electron microscope (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and Raman spectra. The electrochemical properties of electrodes were characterized by cyclic voltammetry (CV), galvanostatic current charge and discharge (GCD) and electrochemical impedance spectroscopy (EIS). The specific capacitance of L-AC@MnO2 is 248 F g−1 at a current density of 1 A g−1. The capacitance retention rate of the composite material can still reach 79.3% at 8 A g−1 current the instability after 3000 cycles. The assembled symmetrical supercapacitor exhibits an energy density of 16.6 Wh kg−1 at a power density of 123.7 W kg−1. The result also provides a feasible method for the design and synthesis of electrodes materials in high-performance supercapacitors.
This paper describes the production of selenium sulfide (SeS2) crystalline thin film on commercial glass substrates, via chemical bath deposition. Transmittance, absorption, dielectric constant and refractive index of the produced films were investigated by UV/VIS Spectrum. It was found that changes occurred on the characteristics of the films and they were determined as a function of selenium sulfide concentration, which varied between 2 × 10−3 and 5 × 10−3 M. The structure of the film was analyzed using FTIR spectrum. The calculated refractive index values fell between 1.5 and 1.6, whereas the transmission ratio of the films was around 80–90%. Moreover, a peak in the reflectance was observed at 320–330 nm for all investigated samples. The highest dielectric constant for the films was obtained at the deposition concentration of 0.005 M. This study is believed to be useful for thin film production.
The article provides practical means to monitor batteries that work in the so-called float cycling regime. The main interest of the case study is destined for autonomous solar applications. The problem of the state-of-charge estimation of lead-acid storage unit is studied. Two approaches are considered and compared: the sliding mode technique and the fuzzy logic modelling. Based on the grounds of observers design theory, it was shown that the sliding mode technique exhibits robustness properties in the face of parameters imprecision and unknown non-linear behaviour. The fuzzy logic modelling approach allows designing the monitoring scheme using the reduced number of available information. An evolutionary programming technique is applied to adjust the parameters of the fuzzy logic resolution scheme. The results are compared with reference state-of-charge measurements taken from an industrial battery charge regulator. The developed models are potentially extensible to other types of storage units.
The overcharge behavior of prismatic lithium ion batteries was studied under abusive conditions. Experimental cells were constructed with a systematic variation in cell balance and overcharge tested to the point of failure. This test demonstrated that the point of cell rupture tracked the amount of cathode in the cell, independent of the amount of anode material. The rate of charge was found to be an important parameter, as cells overcharged at low charge rates remained hermetic while high charge rates (C/2 and above) resulted in cell rupture. The internal temperature of the cells monitored during overcharge was found to be as high as 199°C, which was 93°C higher than the external skin temperature of the cell. Coin cell tests identified the cathode as the source of heat produced in the cell, and Rdc measurements identified a large increase in cell resistance past the full delithiation point of Li x CoO2.
Volume changes associated with the (de)lithiation of a nanostructured Ni3Sn2 coated nickel inverse opal scaffold anode create mismatch stresses and strains between the Ni3Sn2 anode material and its mechanically supporting Ni scaffold. Using in operando synchrotron x-ray diffraction measurements, elastic strains in the Ni scaffold are determined during cyclic (dis)charging of the Ni3Sn2 anode. These strains are characterized using both the center position of the Ni diffraction peaks, to quantify the average strain, and the peak breadth, which describes the distribution of strain in the measured volume. Upon lithiation (half-cell discharging) or delithiation (half-cell charging), compressive strains and peak breadth linearly increase or decrease, respectively, with charge. The evolution of the average strains and peak breadths suggests that some irreversible plastic deformation and/or delamination occurs during cycling, which can result in capacity fade in the anode. The strain behavior associated with cycling of the Ni3Sn2 anode is similar to that observed in recent studies on a Ni inverse-opal supported amorphous Si anode and demonstrates that the (de)lithiation-induced deformation and damage mechanisms are likely equivalent in both anodes, even though the magnitude of mismatch strain in the Ni3Sn2 is lower due to the lower (de)lithiation-induced contraction/expansion.
The cellular diversity of neurons located in the marginal zone (MZ) of the cortex has a crucial role in cortical development. However, little is known about the molecular mechanisms involved in how these different neuronal cell types are specified. Here, we show that in the MZ, the nuclear receptor COUP-TFI is localized in calbindin-positive cells and not in reelin-positive cells. High expression of COUP-TFI has been detected in preplate (PP) and subplate (SP) cells, suggesting that this nuclear receptor is down-regulated during preplate differentiation towards the Cajal-Retzius (CR) cell lineage. By maintaining high ectopic expression of COUP-TFI in preplate cells, we show that COUP-TFI represses the CR cell markers reelin and calretinin, and with lower efficiency the transcription factor Tbr1. Furthermore, general differentiation is not affected, strongly suggesting that COUP-TFI represses differentiation of CR cells.
Li3VO4-coated Li[Ni0.5Co0.2Mn0.3]O2 cathode material exhibits much better cycling stability, rate capability, and high voltage cycling behavior than pristine Li[Ni0.5Co0.2Mn0.3]O2 at room temperature. The sample coated with 3 wt.% Li3VO4 shows the optimum electrochemical performance. It delivers a capacity of 61.5 mAh g−1 at 10 C (1800 mA g−1) after 100 cycles. The capacity retention at 1 C (180 mA g−1) is 63.5% at cut-off voltage 4.6 V, and 63.0% at a higher cut-off voltage 4.8 V. XRD and XPS results reveal that the Li3VO4 coating layer reinforces the surface of matrix material, which benefits structural stability of Li[Ni0.5Co0.2Mn0.3]O2 during long-term cycling. CV and EIS tests indicate that the improvement of electrochemical performances could be attributed to higher Li+ conductivity, suppression of Co and Mn dissolution from Li[Ni0.5Co0.2Mn0.3]O2, and decreased polarization during cycling since Li3VO4 layer on Li[Ni0.5Co0.2Mn0.3]O2 surface acts as a relatively stable protective barrier as well as an excellent Li-ion conductor.
PVDF-CNT membranes were fabricated using thermally induced phase separation (TIPS) protocol. The membranes are extremely tensile, strong and robust. Membranes exhibit hydrophilic behavior with decreasing contact angle (CA < 90°) in saline environment. Crystal study (XRD) of membranes reveals ɑ-phased PVDF with hexagonal (002) oriented CNTs within the polymer matrix. The morphology (SEM) and thermal analysis (TGA) reveals that the material is made of several porous zones and the material is chemically and thermally stable up to 500 °C. Raman and FTIR spectrum shows ordered bands of the D and G with complete grafting of PVDF bonds with CNTs respectively.
Highly conductive paper was fabricated through polypyrrole (PPy) coating on common printing paper by a simple and low-cost “soak and polymerization” method. The as-fabricated porous, flexible and conductive paper shows a high electrical conductivity of 15 S cm−1 and a low sheet resistance of 4.5 Ω sq−1. Flexible solid-state supercapacitors assembled with PPy/paper composite electrodes had an average weight of 55 mg and an areal capacitance of 0.42 F cm−2, indicating a high energy density of 1 mW h cm−3 at a power density of 0.27 W cm−3 normalized to the volume of the whole cell (electrode, electrolyte, and separator). Furthermore, this method could be easily scaled up to large-scale fabrication of conductive paper and opened up new opportunities for flexible energy storage.
Vulcanized rubber products contain polymer backbones crosslinked with sulfur to improve mechanical strength. Burning of waste rubber products emits toxic gases, and recycling of rubber by breaking the C–S bond with costly reagents and heat is also haunted by environmental concerns. The crosslinked polymers can be extracted chemically at room temperature and, by a simple solution-drop method, used to prepare a bifunctional cathode layer on the cathode current collector of a Li–S battery. The C–S bond of the crosslinking sulfur can be broken reversibly in a discharge/recharge cycle to provide a sulfur source, and the broken carbon bond can capture a lithium polysulfide soluble in a liquid organic electrolyte by forming a C–Li–S bond during discharge. During charge, the Li is extracted and the C–S bond is reformed. However, added sulfur powder is also needed in the cathode of a Li–S battery. The data also provide a low-cost way to recycle waste rubber electrochemically.