Abstract: Disclosed is a free-standing porous separator including a plurality of inorganic particles and a binder polymer positioned on the whole or a part of the surface of the inorganic particles to connect the inorganic particles with one another and fix them, wherein the binder polymer comprises a polyvinylidene fluoride (PVdF)-based binder polymer modified with an ester (COO)- or carboxyl (COOH)-containing monomer. An electrochemical device including the free-standing porous separator is also disclosed. It is possible to provide a porous separator which has a reduced dimensional change in an electrolyte, while showing improved tensile strength and/or elongation at the same time.

Abstract: A method for manufacturing unit cells includes preparing a pre-cell having a first separator sheet and a plurality of first electrodes disposed on the first separator sheet while being spaced apart from one another; forming a cutting guide line having a plurality of though-holes spaced apart from one another on the pre-cell; and cutting the pre-cell along the cutting guide line to form a plurality of unit cells. An apparatus for manufacturing unit cells includes a hole-forming unit configured to form a cutting guide line on a pre-cell having a separator sheet and electrodes disposed on the separator sheet where the cutting guide line has a plurality of though-holes spaced apart from one another; and a cutting unit configured to cut the pre-cell along the cutting guide line to form a plurality of unit cells.

Abstract: Disclosed is a separator for an electrochemical device containing a lithium manganese-based active material. The separator includes a porous polymer substrate, and a porous coating layer which is laminated on at least one surface of the porous polymer substrate and contains inorganic particles and a polymer binder. The inorganic particles have a sulfonic acid group introduced on the surface of a metal oxide or metal hydroxide, and at least a portion of the sulfonic acid group has hydrogen cations substituted with lithium cations.

Abstract: A separator for an electrochemical device and an electrochemical device comprising the same are provided. The separator comprises a resin mixture containing ethylene vinyl acetate copolymer (EVA) and polyethylene (PE), the ethylene vinyl acetate copolymer (EVA) containing 20 wt. % or less of vinyl acetate (VA) based on the total amount of the ethylene vinyl acetate copolymer (EVA).

Abstract: A method for manufacturing a separator for an electrochemical device including a silicon-based negative electrode is provided. The method includes a step of forming a freestanding porous separator by simultaneously electrospinning a first spinning solution containing a polymer binder and a second spinning solution containing inorganic particles, wherein a flow rate of the second spinning solution is allowed to be greater than that of the first spinning solution such that a separator having compression resistance against expansion of the silicon-based negative electrode during charging and discharging is manufactured.

Abstract: A separator substrate for an electrochemical device. The separator substrate has pores that are small and uniform in size, good physical strength and durability, and high dielectric breakdown voltage. Therefore, with the use of the separator substrate, the probability of short circuiting is low.

Abstract: The separator according to the present disclosure and the electrochemical device including the same show low internal resistance between the separator and an electrode. The separator includes heat resistant particles in a heat resistant coating layer. The heat resistant particles include a particle-shaped inorganic material and fluorine (F) doped to a surface of the inorganic particles. When the internal temperature of a battery is increased during the operation of the battery, the separator shows improved heat resistance by virtue of an endothermic effect derived from a phase change of the heat resistant particles. In addition, decomposition of a lithium salt used as an ingredient of electrolyte is inhibited by the fluorine atoms introduced to the heat resistant particles, resulting in improvement of ion conductivity and resistance characteristics.

Abstract: The present disclosure relates to a separator for a lithium secondary battery comprising a porous substrate, and a porous coating layer disposed on at least one surface of the porous substrate and comprising inorganic particles and binder polymer, wherein the binder polymer is terpolymer including 65 to 90 weight % of a repeat unit derived from vinylidenefluoride (VDF), 1 to 28 weight % of a repeat unit derived from hexafluoropropylene (HFP) and 5 to 28 weight % of a repeat unit derived from chlorotrifluoroethylene (CTFE), and the separator has adhesiveness towards electrode ranging from 30 gf/25 mm to 150 gf/25 mm and machine direction (MD) thermal shrinkage of 1 to 18% and transverse direction (TD) thermal shrinkage of 1 to 17%, and a lithium secondary battery comprising the same, wherein the separator has uniform micropores on the surface, and thus has the increased adhesive surface area with electrode and consequential improved adhesiveness towards electrode.

Abstract: A separator for an electrochemical device, including a porous polymer substrate and an inorganic coating layer formed on at least one surface of the porous polymer substrate. The inorganic coating layer includes inorganic particles and a binder resin. The binder resin includes a polyvinylidene fluoride (PVdF)-based polymer having a main chain, and at least one hydrogen atom in the main chain of the PVdF-based polymer is substituted with an acrylic compound-derived functional group.

Abstract: A separator including a porous polymer substrate, and a porous coating layer, and an electrochemical device comprising the same. The porous coating layer includes P(VDF-TrFE-CTFE) and PVDF-CTFE as a binder polymer. The separator has a lower resistance by changing the characteristics of the binder polymer.

Abstract: Disclosed is a separator for an electrochemical device including a lithium manganese-based active material, which includes a porous polymer substrate; a first porous coating layer, which includes a first inorganic particle and a second inorganic particle having a larger specific surface area than the first inorganic particle and which is present on a first surface of the porous polymer substrate; and a second coating layer present on a second surface of the porous polymer substrate, wherein the second inorganic particle includes sulfonic acid groups on a surface thereof, and in some of the sulfonic acid groups, hydrogen cations are substituted with lithium cations.

Abstract: A polyolefin separator for an electrochemical device, the separator having a plurality of pores having an average pore size of 20 nm to 40 nm and a maximum pore size of 50 nm or less and including a polyolefin resin having a polydispersity index (PDI) of in a range of 2.5 to 4.2. The polyolefin separator may have a strain rate of 25% or less as measured when a tensile stress is applied at 60° C. at 15 MPa for 60 seconds, and the polyolefin separator may have a recovery time of 200 seconds or less to reach a recovery rate of 70% as measured after removing a tensile stress applied at 70° C. at 2 MPa for 180 seconds.

Abstract: The present disclosure relates to a method for manufacturing a separator for an electrochemical device, which includes (S1) preparing a coating slurry including a polymer binder, inorganic particles, and a dispersion medium; (S2) heating at least one surface of a porous substrate; and (S3) applying the coating slurry prepared in the step (S1) to the at least one surface of the porous substrate heated in the step (S2) to form a porous coating layer, wherein the porous coating layer includes an area, where the polymer binder is filmed, in at least a portion of the surface in contact with the porous substrate.

Abstract: The present invention provides a separator for an electrochemical device includes a porous polymer substrate, and a porous coating layer formed on at least one surface of the porous polymer substrate, wherein the porous coating layer includes a polymer binder, and inorganic particles whose surface is modified with one or more compounds selected from the group consisting of coumarin and a derivative thereof.

Abstract: A polyolefin separator for an electrochemical device, the separator having a plurality of pores having an average pore size of 20 nm to 40 nm and a maximum pore size of 50 nm or less and including a polyolefin resin having a polydispersity index (PDI) of in a range of 2.5 to 4.2. The polyolefin separator may have a strain rate of 25% or less as measured when a tensile stress is applied at 60° C. at 15 MPa for 60 seconds, and the polyolefin separator may have a recovery time of 200 seconds or less to reach a recovery rate of 70% as measured after removing a tensile stress applied at 70° C. at 2 MPa for 180 seconds.

Abstract: A separator for an electrochemical device includes a porous polymer substrate; a first coating layer provided on at least one surface of the porous polymer substrate and containing a first polymer resin of a first solubility in an electrolyte; and a second coating layer provided on the first coating layer and including a second polymer resin of a second solubility in the electrolyte, and inorganic particles, wherein the first solubility is higher than the second solubility in the electrolyte, and the separator is provided on a negative electrode containing a silicon (Si).

Abstract: The present disclosure relates to a coating bar and a method for manufacturing a separator using the same. The coating bar according to the present disclosure may form a coating layer having an area with different thicknesses by one coating. Additionally, the method for manufacturing a separator according to the present disclosure includes forming a porous coating layer using a predetermined coating bar, to manufacture a separator including the porous coating layer having an area with different thicknesses. In particular, the present disclosure manufactures the separator having a larger thickness at the two ends than at the center, thereby avoiding a lack of adhesive strength at the two ends in a transverse direction in the adhesion between the separator and the electrode, and exhibiting uniform adhesive strength over the whole interface between the separator and the electrode.

Abstract: The present invention provides a separator for an electrochemical device includes a porous polymer substrate, and a porous coating layer including a first polymer binder and inorganic particles and formed on at least one surface of the porous polymer substrate, wherein the first polymer binder and the inorganic particles each have different ligands introduced thereto.

Abstract: A method of manufacturing a separator for a lithium secondary battery having improved compression resistance is disclosed. According to one aspect of the present disclosure, there is a method of manufacturing a separator for a lithium secondary battery including the steps of coating a polymer solution prepared by dissolving a first polymer soluble in an electrolyte in a solvent to at least one surface of a porous polymer substrate having a plurality of pores, to impregnate the pores of the porous polymer substrate with the polymer solution; and coating and drying a slurry containing a second polymer non-soluble in the electrolyte, on the coated polymer solution.

Abstract: Disclosed is a separator including a separator substrate and an inorganic coating layer disposed on at least one surface of the substrate, wherein a concave pattern portion having a concave pattern is applied merely at the outer circumferential end of the separator substrate. The separator may show excellent resistance characteristics, while ensuring high binding force between the separator substrate and the inorganic coating layer by virtue of such a structural feature. In addition, in the electrochemical device including the separator, the concave pattern portion at the outer circumferential end of the separator is disposed in such a manner that it may be overlapped with the tab portion of an electrode, when the separator is applied to an electrode assembly. In this manner, it is possible to prevent lithium plating.