Lg Chem, Ltd

Lg Energy Solution, Ltd.

Won-Sik Bae

Joo-Sung Lee

Bi-Oh Ryu

Heon-Sik Song

So-Mi Jeong

A-Young Lee

Jong-Yoon Lee

So-Yeong Lee

So-Jung Park

Dong-Wook Sung

Ji-Young Hwang

Sang-Min Kwak

Cheon-Il Park

Kyoung-Min Kim

Sung-Jae Han

Kyeong-Hui Bae

Ho-Sung Kang

Yern-Seung Kim

Je-Seob Park

Se-Jung Park

A crosslinked polyolefin separator and a method of making the same are disclosed herein. The method includes mixing a polyolefin, a diluting agent, an initiator, a crosslinking catalyst, and inorganic particles surface treated with an alkoxysilane containing a carbon-carbon double bonded group in an extruder to obtain a mixture, and then reactively extruding the mixture to form an extruded silane-grafted polyolefin composition; molding and orienting the extruded silane-grafted polyolefin composition in the form of an oriented sheet; extracting the diluting agent from the oriented sheet to obtain a porous membrane; thermally fixing the porous membrane to obtain a thermally fixed porous membrane; and crosslinking the thermally fixed porous membrane in the presence of moisture.

Cross-linked polyolefin separator and manufacturing method therefor

A polyolefin separator is provided in the present disclosure. The polyolefin separator includes a polyolefin porous substrate including a plurality of fibrils and pores formed by the fibrils draped across one another. A coating layer surrounding the outer side of the fibrils is contained in the polyolefin porous substrate and the coating layer includes a crosslinked polymer, wherein the polyolefin separator having the coating layer has a change in air permeability of 20% or less and a change in basis weight of 4% or less, as compared to the polyolefin porous substrate. A method for manufacturing the polyolefin separator and a secondary battery including the polyolefin separator are also disclosed.

Polyolefin separator and method for manufacturing the same

A system for detecting a defective porous sheet includes a jig having a through-hole, a heating unit, a temperature sensor, a controlling unit, an air permeability-determining unit and a judging unit. In this manner, it is possible to provide a novel system for detecting a porous sheet, which may be a defective separator after being coated with a porous coating layer, beforehand by using the air permeability and shut-down temperature of the porous sheet itself.

Defective porous sheet detection system and detection method

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.

Method and apparatus for manufacturing unit cells

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.

Polyolefin separator for an electrochemical device and electrochemical device including same

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.

Coating bar and method for manufacturing separator using the same

Disclosed is a method for pre-detecting a defective porous polymer substrate for a separator, including selecting a porous polymer substrate having a plurality of pores; observing the selected porous polymer substrate with a scanning electron microscope (SEM) to obtain an image of the porous polymer substrate; quantifying the average value of pore distribution index (PDI); correcting the quantified average value of pore distribution index to obtain the corrected average value of pore distribution index; determining whether or not the corrected average value of pore distribution index is 60 a.u. (arbitrary unit) or less; and classifying the porous polymer substrate as a good product, when the corrected average value of pore distribution index is determined to be 60 a.u. or less, and classifying the porous polymer substrate as a defective product, when the corrected average value of pore distribution index is determined to be larger than 60 a.u.

Method for pre-detecting defective porous polymer substrate for separator

A crosslinked polyolefin separator having an average value of light transmittance of 30% or more in a region of 380 nm to 700 nm, after four sides of the separator are fixed and allowed to stand at 130° C. for 30 minutes. A method for manufacturing the crosslinked polyolefin separator is also provided. The crosslinked polyolefin separator has a low shutdown temperature to provide improved safety. The crosslinked polyolefin separator also has a high meltdown temperature and is inhibited from die-drooling.

Cross-linked polyolefin separator and method for producing same

A crosslinked polyolefin separator which has gels with a longer side length of 50 &#x3bc;m or more in a number ranging from 0 to 3 per 1 mof the separator, and shows a standard deviation of absorbance ratio between the center of the separator and the side thereof ranging from 0.01 to 0.5 is provided. A method for manufacturing the crosslinked polyolefin separator is also provided. The method includes (S1) preparing a polyolefin porous membranes, and (S2) applying a coating solution containing an initiator and alkoxy group-containing vinylsilane onto at least one surface of the porous membrane. The coating solution can permeate even to the inside of exposed pores. Thus, it is possible to provide a crosslinked polyolefin separator in which silane crosslinking occurs uniformly even inside of the pores.

Crosslinked polyolefin separator and manufacturing method therefor

A method for manufacturing a crosslinked polyolefin separator and the crosslinked polyolefin separator obtained therefrom are provided. The method includes non-grafted polyolefin having a weight average molecular weight of 300,000 or more and silane-grafted polyolefin having a weight average molecular weight of 300,000 or more. The method minimizes gel formation, a side reaction occurring in an extruder during the manufacture of the separator, and provides the separator having a uniform surface.

Cross-linked polyolefin separator and manufacturing method thereof

A method for manufacturing a crosslinked polyolefin separator and the crosslinked polyolefin separator obtained by the method are provided. The method includes (S1) mixing polyolefin, a diluting agent, an initiator and alkoxysilane containing a carbon-carbon double bonded group to an extruder, and then carrying out extrusion to obtain a silane-grafted polyolefin composition; (S2) molding and orienting the extruded silane-grafted polyolefin composition in the form of a sheet; (S3) introducing the oriented sheet to an extraction water bath containing a crosslinking catalyst to extract the diluting agent and perform aqueous crosslinking; and (S4) thermally fixing a resultant aqueous crosslinked product. The method can provide a separator having a high meltdown temperature and improved heat shrinkage.

Crosslinked polyolefin separator and method for manufacturing the same

A method for manufacturing a crosslinked polyolefin separator and a separator are provided. The method includes putting a polyolefin and a polyolefin elastomer into an extruder first, and putting an alkoxy silane containing a carbon-carbon double bond functional group, an initiator and a crosslinking catalyst to form the separator. The crosslinked polyolefin separator has high meltdown temperature and low shutdown temperature.

Crosslinked polyolefin separator and manufacturing method thereof

A method for manufacturing a crosslinked polyolefin separator, including the steps of: (S1) introducing polyolefin having a weight average molecular weight of 200,000-1,000,000, a first diluting agent, alkoxysilane containing a carbon-carbon double bonded group, an initiator and a crosslinking catalyst to an extruder; (S2) introducing a second diluting agent to the extruder, followed by mixing, to carry out reactive extrusion of a silane-grafted polyolefin composition; (S3) molding and orienting the reactive extruded silane-grafted polyolefin composition in a form of a sheet; (S4) extracting the first diluting agent and the second diluting agent from the oriented sheet to obtain a silane-grafted polyolefin porous membrane; (S5) thermally fixing the porous membrane; and (S6) crosslinking the porous membrane in the presence of water and a crosslinked polyolefin separator are provided. According to the method, it is possible to provide a separator which shows a decrease in intensive silane crosslinking on the surface thereof.

Cross-linked polyolefin separator and manufacturing method for same

Disclosed is a method of preparing a crosslinked polyolefin separator including preparing a silane grafted polyolefin solution using a polyolefin having a weight average molecular weight higher than or equal to 200,000, a diluent, an alkoxy group containing vinylsilane, and an initiator, forming the silane grafted polyolefin solution in a sheet shape and stretching, extracting the diluent from the stretched sheet to produce a porous membrane, and crosslinking the porous membrane in the presence of water, and a crosslinked polyolefin separator.

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Daejeon, South Korea

Won-Sik Bae