Papers by Keyword: Separator

Abstract: A separator is one of the main components of lithium-ion batteries. It separates the cathode and anode while allowing the exchange of ions, and reduces the risk of a short circuit that can cause battery failure. In this study, membranes consisting of electrospun, SiO₂-containing, poly(vinylidene fluoride) nanofibers were synthesized for use as separators in lithium-ion batteries. Moreover, this study investigated the effect of the volume of colloidal SiO₂ (1, 2, and 3 mL) in the precursor (a PVDF/SiO₂ solution containing 10 mL of PVDF solution) on the properties of an associated nanofiber membrane and its performance in a coin cell battery. It was found that the porosity, mechanical strength, and thermal resistance of PVDF/SiO₂ nanofiber membranes increase with the increasing volume of colloidal SiO₂ in the precursor. The PVDF/SiO₂ precursor containing 3 mL SiO₂ produces an optimal membrane separator with a porosity of 67%, thermal shrinkage ratio of 1.3%, and elongation at break of 24%. These results show that PVDF/SiO₂ separators have higher porosity rates than pp and PE membrane separators. Furthermore, the corresponding coin cell battery achieves the highest charge and discharge capacities, i.e., 2.36 and 1.36 mAh/g, respectively.

Abstract: Lithium-ion batteries have the main component include a positive electrode, negative electrode, liquid electrolyte, and membrane separator. The separator was used to secure the battery by preventing it from short circuits. In this paper, the separator PVDF/SiO₂ (Polyvinylidene fluoride/Silica) nanofiber membrane was synthesized by double jet sprayers electrospinning method on rotating cylinder collector. The SiO₂ colloid nanoparticle concentration was varied at 1000, 2500, and 5000 ppm. The effect of the SiO₂ nanoparticle addition to the PVDF nanofiber membrane to improve membrane characteristics, including porosity, high temperature stability mechanical, mechanical strength, and battery capacity stability, were systematically investigated. The PVDF/SiO₂ results have a fibrous structure with SiO₂ adhering to the fibers' surface. The membrane separator's average thickness is 10.2 micrometers. A large amount of SiO₂ addition (SiO₂ 5000 ppm) on the PVDF nanofibers membrane increased porosity, mechanical properties, and stability at a temperature of 150 °C.

Abstract: The proposed method is a dry separation tailings. A separator developed for separating the tailings of the quartz sand and iron-bearing components. The efficiency of separation of enrichment tails in the fluidized bed separator is shown. The use of mill tailings as components in the manufacture of building materials is practically confirmed by testing samples of fine-grained concrete and asphalt.

Abstract: Retaining structure of homogeneous fluid and granular stream is one of the main criteria for technological process assuring the high quality outcome in many industries, including mechanical engineering and oil & gas industry. For example, in oil and gas industry during the pipeline transportation of oils there is a strong trend for cluster aggregation, and particle coarsening and entanglement. Dehomogenization of particle stream results in reverse dynamics of the stream. The importance of prevention and minimization of small particles coalescence by separating the oil stream leads to the need of improving the properties of the dispersers to boost their efficiency. Our paper investigates the operating principle of the disperser for separating particles (separator), which is designed by the authors. We have considered a particle stream of dispersed structure. We have obtained the conformity with the stability of the disperser operation. To yield the results we use the extremum problems for differential equations. This approach provides strong evidence that there are optimum parameters of the dispersers, which result in better stability of the particle stream.

Abstract: A study concerning the effect of TiO₂ on duck eggshell membrane as separator in supercapacitor applications. Concentration of TiO₂ on duck eggshell membrane are 1 %wt, 5 %wt and 10 %wt respectively. Construction capacitor cell is shaped sandwich system. Membrane separator placed in the midst of the two carbon electrodes containing H₂SO₄ solution. From the micrograph Scanning Electron Microscopy (SEM), it observed that TiO₂ particles in all samples are uniform in size. At concentration of 1 %wt, TiO₂ particles covered all fiber of duck eggshell membrane, but not many pore is formed while at concentration of 5%, the TiO₂ particles fill the pores between the fibers, thus causing the pores between the fibers get smaller and multiplied in number. However, if the TiO₂ particles added is the more than 10 %wt, the particles will actually cover the pores between the fibers of the membrane. Characteristics of the capacitor was measured by using Edaq cyclic voltameter. Maximum value of specifics capacitance (C_sp) was 2.3 F / g, with current 0.007 mA and voltage of 0.002 V. This value occurs at a concentration of 5 wt% TiO₂ on the charging time for 20 seconds.

Abstract: Stress-strain state (SSS) of the separator as one of the main elements of the geokhod harmonic gear drive with rolling elements with hollow shaft is considered. The study was conducted by Finite Element Method (FEM) using SolidWorks Simulation software.

Abstract: Medical facilities and similar types of medical centres providing surgical or ambulant care are nowadays unable to manage without a strict hygienic sterilization of medical instruments. The clean steam, necessary for the requested sterilizations, must meet the requirements of European Standard EN 285 and that is particularly from the point of quality, pressure and requested volume in random time period. Production of clean steam is technically and financially very demanding. This contribution is aimed on newly developed Pure Steam system with STEAMEX clean steam generator.

Abstract: The method of numerical simulation of the centrifugal separator is presented. The separator carries out alternative way of mechanical cleaning petroleum products from inclusions of water and sludge. Questions of the boundary conditions, creation of a settlement mesh and a method of calculation of two-phase liquid are considered.

Abstract: Zirconia fiber separator is one of the important materials of nickel-hydrogen battery .In this paper,we studied the factors affecting the properties of zirconia fiber separator used as nickel-hydrogen battery separator, which prepared by precursor process, including the precursor fibers,fibrous cloths,concentration of the precursor solution and the heating rate before 500oC.The results show that, because the gully structure copied the precursor fibers, as well as smaller diameter of the fiber has larger specific surface area, so the zirconia cloth has the higher absorption capacity and retention ability of alkal. In the same way as woven, the low fabric areal density is beneficial to the absorption ability. When the concentration of the precursor solution is 1.36g/ml, the properties of the zirconia fiber separator is the best. If the heating rate is too fast, will cause a decrease in performance of zirconia fiber separator. The diameter of the fibers in the zirconia fiber sepatator is about 4-5μm, the main phase of the separator is tetragonal zirconia.

Abstract: Various eggs shell membranes (ESMs) have been used as a separator for supercapacitor application. The separator was prepared from different membranes such as chicken eggs shell membrane (CESM), duck eggs shell membrane (DESM) and goose eggs shell membrane (GESM). The ESMs were tested as a separator in a two-electrode system, the sandwich-type supercapacitor cell consists of two activated carbon monoliths as electrodes, two stainless steel as current collectors and 1 M H₂SO₄ solution as an electrolyte. The electrochemical performance of the ESMs was characterized by an electrochemical impedance spectroscopy, a cyclic voltammetry and a galvanostatic charge-discharge. The results of this study exhibit all of the ESMs as a good candidate for supercapacitor separator. However, the CESM was shown excellence electrochemical properties, such as low resistance, high energy density and power density. The scanning electron microscope (SEM) micrograph and X-ray diffraction analysis were also proved that the ESMs are a promising low-cost separator for supercapacitor application.