Sk Innovation Co., Ltd.

Sk Energy Co., Ltd.

Sk Corporation

Sk Ie Technology Co., Ltd.

Jang Weon Rhee

Young Keun Lee

Jung Moon Sung

Byoung Cheon Jo

In Hwa Jung

Chol Ho Lee

Won Young Cho

Byung Rae Jung

Je An Lee

Dong Jin Joo

Yong Kyoung Kim

Gwi Gwon Kang

Disclosed is a microporous composite film having a coating layer formed on at least one surface of a microporous polyolefin film, wherein the coating layer simultaneously includes a high thermostable polymer resin and inorganic particles. More specifically, the present invention relates to a microporous composite film in which an area shrinkage at 170&#xb0; C. for 1 hr is 10% or less; a tensile modulus in each of a machine direction and a transverse direction at 130&#xb0; C. is 0.5 MPa to 7.0 MPa; a ratio between permeability of a microporous composite film (CCS) and permeability of a microporous polyolefin film (S) is 1.1&#x2266;CCS/S&#x2266;3.5; and a permeability of the microporous composite film is 450 sec or less.

Microporous composite film with high thermostable organic/inorganic coating layer

Provided is a porous multi-layer film having two or more layers that is used as a separator for battery. In the film, more than 2 layers have different porosities and pore sizes. The film has a thickness of 9 to 50 &#x3bc;m, a machine direction (MD) loop stiffness of 0.008 mg/&#x3bc;m or more, puncture strength of 0.15 N/&#x3bc;m or more, permeability of 1.5&#xd7;10Darcy or more, shut-down temperature of 140&#xb0; C. or less, melt-down temperature of 170&#xb0; C. or more, a transverse direction (TD) maximum shrinkage of 25% or less in Thermomechanical Analysis (TMA) under a load of 1 mN/(1 &#x3bc;m&#xd7;6 mm), and melt down temperature of 160&#xb0; C. or more. Since the porous multi-layer film shows excellent thermal stability at high temperature and electrolyte retaining property due to a dual pore structure, the film shows a superior effect when used as a separator for high-capacity/high-power lithium ion battery.

Porous multi-layer film with improved thermal properties

Disclosed herein is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film is made from a resin composition. The resin composition comprises 100 parts by weight of a polyethylene composition including 10-50 wt % polyethylene having a weight average molecular weight of from 2&#xd7;10to less than 5&#xd7;10(component I) and 90-50 wt % diluent (component II), and 0-150 parts by weight of inorganic powder (component III). The film has a puncture strength of 0.20 N/&#x3bc;m or more and a gas permeability (Darcy's permeability constant) of 1&#xd7;10Darcy or more. The microporous polyethylene film has excellent physical properties, thus improving the performance and stability of a battery.

Microporous polyethylene film having excellent physical properties, productivity, and quality consistency, and method of producing same

Disclosed is a microporous high density polyethylene film for a battery separator and a method of producing the same. The microporous high density polyethylene film includes high density polyethylene with a weight average molecular weight of 2&#xd7;10-5&#xd7;10, containing 5 wt % or less molecule with a molecular weight of 1&#xd7;10or less. The microporous high density polyethylene film has tensile strengths of 1,100 kg/cmor more in transverse and machine directions respectively, a puncture strength of 0.22 N/&#x3bc;m or more, a gas permeability (Darcy's permeability constant) of 1.3&#xd7;10Darcy or more, and shrinkages of 5% or less in machine and transverse directions, respectively. Particularly, the microporous high density polyethylene film has an excellent extrusion-compoundabiliy and stretchability and a high productivity, and can improve the performances and stability of a battery produced using the same.

Method of producing microporous high density polyethylene film

Disclosed is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film comprises a resin mixture, which includes 100 parts by weight of composition containing 20-50 wt % polyethylene with a weight average molecular weight of 5&#xd7;10-3&#xd7;10(component I) and 80-50 wt % diluent (component II), 0.1-2 parts by weight of peroxide (component III), and 0.05-0.5 parts by weight of anti-oxidant (component IV). The microporous polyethylene film has a puncture strength of 0.22 N/&#x3bc;m or more and a gas permeability (Darcy's permeability constant) of 1.3&#xd7;10Darcy or more. The present invention increases production efficiency of the microporous film, and improves performances and stability of the battery when the microporous polyethylene film is used in a battery separator.

Microporous polyethylene film and method of producing the same

Microporous high density polyethylene film

Growing community of inventors

Daejeon, South Korea

Jang Weon Rhee