A separator for a lithium secondary battery and a method for manufacturing the same. The separator for a lithium secondary battery includes: a porous polymer substrate; and a porous coating layer on at least one surface of the porous polymer substrate. The porous coating layer includes inorganic particles, a fluorine-containing binder polymer (A), and an ethylenic copolymer (B) having an ethylene monomer-derived repeating unit (a) and a vinyl acetate monomer-derived repeating unit (b). It is possible to provide a separator having improved adhesion peel strength between the porous coating layer and the porous polymer substrate and improved adhesion Lami strength to an electrode at the same time and a method for manufacturing the same by using an ethylenic copolymer having predetermined characteristics.

A separator for a lithium secondary battery and a method for manufacturing the same. The separator for a lithium secondary battery includes: a porous polymer substrate; and a porous coating layer on at least one surface of the porous polymer substrate. The porous coating layer includes inorganic particles, a fluorine-containing binder polymer (A), and an ethylenic copolymer (B) having an ethylene monomer-derived repeating unit (a) and a vinyl acetate monomer-derived repeating unit (b). It is possible to provide a separator having improved adhesion peel strength between the porous coating layer and the porous polymer substrate and improved adhesion Lami strength to an electrode at the same time and a method for manufacturing the same by using an ethylenic copolymer having predetermined characteristics.

A method and apparatus for manufacturing a separator, and a separator obtained thereby. The method for manufacturing a separator includes applying a solvent for pore impregnation onto a first surface of a porous polymer substrate, before applying slurry for forming a first porous coating layer and a second porous coating layer. In this manner, it is possible to provide a separator which has a small deviation in physical properties between the porous coating layers on the first surface and the second surface of the porous polymer substrate.

The present disclosure relates to a method and apparatus for manufacturing a separator, and a separator obtained thereby. The method for manufacturing a separator according to an embodiment of the present disclosure includes applying a solvent for pore impregnation onto a porous polymer substrate, before applying slurry for forming a porous coating layer thereto. In this manner, it is possible to provide a separator which shows a small deviation in physical properties between the porous coating layers formed on the top surface and the back surface of the porous polymer substrate.

A method and apparatus for manufacturing a separator, and a separator obtained thereby. The method for manufacturing a separator includes applying a solvent for pore impregnation onto a first surface of a porous polymer substrate, before applying slurry for forming a first porous coating layer and a second porous coating layer. In this manner, it is possible to provide a separator which has a small deviation in physical properties between the porous coating layers on the first surface and the second surface of the porous polymer substrate.

The present disclosure relates to a method and apparatus for manufacturing a separator, and a separator obtained thereby. The method for manufacturing a separator according to an embodiment of the present disclosure includes applying a solvent for pore impregnation onto a porous polymer substrate, before applying slurry for forming a porous coating layer thereto. In this manner, it is possible to provide a separator which shows a small deviation in physical properties between the porous coating layers formed on the top surface and the back surface of the porous polymer substrate.

In a non-aqueous electrolyte secondary battery according to one exemplary embodiment, a separator includes a substrate, a first filler layer containing phosphate particles and formed on at least one surface of the substrate, and a second filler layer containing inorganic particles and formed on a surface of the first filler layer on the side of the at least one surface of the substrate. The phosphate particles have a BET specific surface area of 5 m.sup.2/g or more and 100 m.sup.2/g or less.

In a non-aqueous electrolyte secondary battery according to one exemplary embodiment, a separator includes a substrate, a first filler layer containing phosphate particles and formed on at least one surface of the substrate, and a second filler layer containing inorganic particles and formed on a surface of the first filler layer on the side of the at least one surface of the substrate. The phosphate particles have a BET specific surface area of 5 m.sup.2/g or more and 100 m.sup.2/g or less.

Disclosed is a functional layer for an electrochemical device that comprises inorganic particles and a particulate polymer, wherein the functional layer comprises a particle-detached portion, in a plan view of a surface of the functional layer, a ratio of an area of the particle-detached portion in a total area of the particulate polymer and the particle-detached portion is 0.1% or more and 40.0% or less, and a volume-average particle diameter of the particulate polymer is larger than a thickness of an inorganic particle layer comprising the inorganic particles.

Disclosed is a functional layer for an electrochemical device that comprises inorganic particles and a particulate polymer, wherein the functional layer comprises a particle-detached portion, in a plan view of a surface of the functional layer, a ratio of an area of the particle-detached portion in a total area of the particulate polymer and the particle-detached portion is 0.1% or more and 40.0% or less, and a volume-average particle diameter of the particulate polymer is larger than a thickness of an inorganic particle layer comprising the inorganic particles.

A method for manufacturing a separator for an electrochemical device which uses polyvinyl pyrrolidone (PVP) as a dispersing agent, and provides high dispersibility of particles and prevents aggregation of particles, even when inorganic particles having a small particle diameter is used in slurry for forming a porous coating layer. Therefore, the inorganic particles are distributed homogeneously in the porous coating layer of a finished separator. In addition, since PVP is used with a fluorinated binder resin, the separator shows improved peel strength and adhesion to an electrode. Further, a non-solvent ingredient for the fluorinated binder resin is used as a solvent for PVP, and a non-solvent ingredient for PVP is used as a solvent for the fluorinated binder resin.

A method for manufacturing a separator for an electrochemical device which uses polyvinyl pyrrolidone (PVP) as a dispersing agent, and provides high dispersibility of particles and prevents aggregation of particles, even when inorganic particles having a small particle diameter is used in slurry for forming a porous coating layer. Therefore, the inorganic particles are distributed homogeneously in the porous coating layer of a finished separator. In addition, since PVP is used with a fluorinated binder resin, the separator shows improved peel strength and adhesion to an electrode. Further, a non-solvent ingredient for the fluorinated binder resin is used as a solvent for PVP, and a non-solvent ingredient for PVP is used as a solvent for the fluorinated binder resin.