Provided herein is a separator used for an electrochemical device such as a lithium-ion battery. The separator disclosed herein comprises a porous base material, and a protective porous layer coated on one or both surfaces of the porous base material disclosed herein, wherein the protective porous layer comprises an organic binder and an inorganic filler, and wherein the inorganic filler comprises a whisker-type material selected from the group consisting of Al.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, BaO.sub.x, ZnO, CaCO.sub.3, TiN, AlN, MTiO.sub.3, K.sub.2O.nTiO.sub.2, Na.sub.2O.mTiO.sub.2, and combinations thereof, wherein x is 1 or 2; M is Ba, Sr or Ca; n is 1, 2, 4, 6 or 8; and m is 3 or 6. Also provided herein is a lithium-ion battery including the separator disclosed herein. The separator disclosed herein is excellent in terms of safety, ion permeability, and cycle characteristics.

In the present invention, in laminated separator rolls 12U and 12L, laminated long separator sheets 12a and 12b are wound such that a surface B (which is of an aramid layer (heat-resistant layer) and is opposite to a surface contacting with the porous film) faces an inner side (core u, l side). From this, it is possible to provide the laminated separator roll which can inhibit change in color of the porous layer included in the porous long separator sheet.

The present invention relates to a method for manufacturing a polyimide-powder composite separator using water and a polyimide-powder composite separator manufactured by the method, and is environmentally friendly since an organic solvent is not used in the overall process of manufacturing the composite separator and has advantageous effects in terms of time, cost, and manufacturing process since a high temperature/high pressure environment is not required.

A separator for a rechargeable battery includes a porous substrate and a heat resistance layer on at least one surface of the porous substrate. The heat resistance layer includes an acryl-based copolymer, an alkali metal, and a filler. The acryl-based copolymer includes a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit.

A first separator (130) covers a first surface of a cathode electrode (110). The first separator (130) has a melting point of a first temperature. A second separator (140) covers a second surface of the cathode electrode (110). The second separator (140) has a melting point of a second temperature higher than the first temperature. An adhesive layer (132) is formed by melting a portion of the first separator (130). The adhesive layer (132) pastes the first separator (130) and the second separator (140) to each other.

An alkaline electrochemical cell includes a cathode, an anode which includes an anode active material, and a non-conductive separator disposed between the cathode and the anode, wherein from about 20% to about 50% by weight of the anode active material relative to a total amount of anode active material has a particle size of less than about 75 μm, and wherein the separator includes a unitary, cylindrical configuration having an open end, a side wall, and integrally formed closed end disposed distally to the open end.

The disclosure relates to the field of lithium-ion batteries, and discloses a polymer composite membrane and a method for preparing same. The disclosure further includes a lithium-ion battery for which the foregoing polymer composite membrane is used. The polymer composite membrane includes a porous base membrane and a heat-resistant fiber layer covering at least one side surface of the porous base membrane, where materials of the heat-resistant fiber layer contain a first polymeric material and a second polymeric material.

Embodiments of the present application relate to an electrochemical device. Specifically, the electrochemical device includes a cathode, an anode and a separator, the separator being disposed between the cathode and the anode, the separator including a porous substrate and a porous layer, and the porous layer being disposed on a surface of the porous substrate and including inorganic particles and a binder, where a ratio of a puncture elongation of the porous substrate to a puncture force of the porous substrate is about 1.5 mm/N to about 25 mm/N. A lithium-ion battery including the separator, provided by the present application, improves the safety performance of the lithium-ion battery.

An electrode body includes: a positive electrode that includes a positive electrode active material layer; a negative electrode that includes a negative electrode active material layer; and a separator that electrically separates the positive electrode and the negative electrode from each other, in which the positive electrode active material layer and the separator contain N-methylpyrrolidone (NMP). A N-methylpyrrolidone (NMP) content in the positive electrode active material layer is 54 ppm to 602 ppm with respect to a total solid content of the positive electrode active material layer, and a N-methylpyrrolidone content (NMP) in the separator is 10 ppm to 26 ppm with respect to the total solid content of the positive electrode active material layer.

A method for film production includes the steps of obtaining information on the position of a defect (D) in a separator (12a) and providing marks (LA, LB) at the respective positions in the vicinity of the defect (D), the marks indicating the position of the defect.