Optimization of Lithium iron phosphate delithiation voltage for energy storage application

Olivine-type lithium iron phosphate (LiFePO4) has become the most widely used cathode material for power batteries due to its good structural stability, stable voltage platform, low cost and high safety. The olivine-type iron phosphate material after delithiation has many lithium vacancies and strong cation binding ability, which is conducive to the large and rapid insertion of alkaline ions such as lithium, sodium and potassium. Therefore, the investigation of delithiation technology is of great significance. Electrochemical delithiation is a common method for preparing olivine-structured FePO4, which can maintain the structural stability and integrity of the material. In this work, the effect of voltage on the delithiation of LiFePO4 material was investigated by the electrochemical delithiation method in Na2SO4 as delithiation solution. The results show that 2.0 V is the best delithiation voltage, and the as-prepared FeO4 exhibits the highest specific capacity of 137.7 mAh g-1

Optimization of Lithium iron phosphate delithiation voltage for energy storage application

Olivine-type lithium iron phosphate (LiFePO4) has become the most widely used cathode material for power batteries due to its good structural stability, stable voltage platform, low cost and high safety. The olivine-type iron phosphate material after delithiation has many lithium vacancies and strong cation binding ability, which is conducive to the large and rapid insertion of alkaline ions such as lithium, sodium and potassium. Therefore, the investigation of delithiation technology is of great significance. Electrochemical delithiation is a common method for preparing olivine-structured FePO4, which can maintain the structural stability and integrity of the material. In this work, the effect of voltage on the delithiation of LiFePO4 material was investigated by the electrochemical delithiation method in Na2SO4 as delithiation solution. The results show that 2.0 V is the best delithiation voltage, and the as-prepared FeO4 exhibits the highest specific capacity of 137.7 mAh g-1

Alkali ions pre-intercalation and reduced graphene coating of MnO2 for high-capacity Li-ion battery

MnO2 is considered to be a prospective material for lithium-ion batteries anode. However, in practical applications, MnO2 has shortcomings such as low conductivity, large volume change and high charge transfer resistance, which seriously hinder its commercial application. In this work, MnO2 are preintercalated with various alkali cations (Na+, or NH4+) and coating with reduced graphene oxide through electrodeposition which designed for LIBs to improve its electrochemical behavior and understand the effect of cations and coating. It demonstrates that alkali cations can affect the growth morphology and electrochemical performance of MnO2, and graphene can improve electrical conductivity. Due to the advantages of its structure, MnO2&NH4+@rGO shows high capacity, rate performance (640 mAh g-1) and a long lifetime in lithium-ion batteries

High strength composites using interlocking carbon nanotubes in a polyimide matrix

Polyethylene was crystallized on carbon nanotubes (CNTs) resulting in the formation of nanosheets on the surface. The material was then carbonized in sulfuric acid at 20 degrees C for 24 h, resulting in a carbon shish-kebab (CSK) structure. Incorporating the CSKs in polyimide (PI) matrix produced a uniform dispersion in which interactions between the nodules producing an interlocking effect that significantly improved the load transfer between the matrix and the CNTs. Consequently, the CSK/PI composite showed a 27% increase in tensile strength, compared to one using pristine CNTs, and 100% increase in the strain compared to the pure PI membrane

Significant enhancement in the electrical conductance properties of ethylene propylene diene monomer using the nano‐SiO2 particles

Abstract To study the effect of nano‐silica particles on the conductivity characteristics of ethylene propylene diene monomer (EPDM) insulation, EPDM nanocomposites with different mass fractions of nano silica were prepared via the melt‐blending method. Scanning electron microscopy was used to analyze the dispersion of nanoparticles in EPDM. Based on the Fourier‐transform infrared spectrum, the bonding properties between the nanoparticles and EPDM were analyzed. The steady‐state current at 30–100 °C and 1–20 kV/mm was measured. Moreover, the conductivity characteristic was analyzed. The experimental results show that as the content of nano‐silica increases, the electrical conductivity of EPDM nanocomposite as well as the threshold field strength gradually decreases. Samples with a small number of nanoparticles will increase the activation energy of the carrier conductivity, and the interface region effect introduced by nanoparticles will reduce the carrier mobility and concentration, resulting in a lower conductivity. Comparing the calculated value of the dielectric constant with the measured value can conclude that the high‐field conductance process is a combination of the electrode effect and the body effect, which in this case, Schottky effect dominates

Transcriptomic and Quantitative Proteomic Analyses Provide Insights Into the Phagocytic Killing of Hemocytes in the Oyster Crassostrea gigas

As invertebrates lack an adaptive immune system, they depend to a large extent on their innate immune system to recognize and clear invading pathogens. Although phagocytes play pivotal roles in invertebrate innate immunity, the molecular mechanisms underlying this killing remain unclear. Cells of this type from the Pacific oyster Crassostrea gigas were classified efficiently in this study via fluorescence-activated cell sorting (FACS) based on their phagocytosis of FITC-labeled latex beads. Transcriptomic and quantitative proteomic analyses revealed a series of differentially expressed genes (DEGs) and proteins present in phagocytes; of the 352 significantly high expressed proteins identified here within the phagocyte proteome, 262 corresponding genes were similarly high expressed in the transcriptome, while 140 of 205 significantly low expressed proteins within the proteome were transcriptionally low expressed. A pathway crosstalk network analysis of these significantly high expressed proteins revealed that phagocytes were highly activated in a number of antimicrobial-related biological processes, including oxidation–reduction and lysosomal proteolysis processes. A number of DEGs, including oxidase, lysosomal protease, and immune receptors, were also validated in this study using quantitative PCR, while seven lysosomal cysteine proteases, referred to as cathepsin Ls, were significantly high expressed in phagocytes. Results show that the expression level of cathepsin L protein in phagocytes [mean fluorescence intensity (MFI): 327 ± 51] was significantly higher (p < 0.01) than that in non-phagocytic hemocytes (MFI: 83 ± 26), while the cathepsin L protein was colocalized with the phagocytosed Vibrio splendidus in oyster hemocytes during this process. The results of this study collectively suggest that oyster phagocytes possess both potent oxidative killing and microbial disintegration capacities; these findings provide important insights into hemocyte phagocytic killing as a component of C. gigas innate immunity