Separator for battery and manufacturing method thereof

A separator and battery technology, applied in the field of battery separators, can solve problems such as film rupture and achieve the effect of excellent electrode adhesion

Active Publication Date: 2021-11-30
TORAY IND INC
View PDF9 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, if the internal temperature of the battery continues to rise after the pores are sealed for some reason, the microporous membrane made of polyethylene may shrink and cause membrane rupture.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Separator for battery and manufacturing method thereof
  • Separator for battery and manufacturing method thereof
  • Separator for battery and manufacturing method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0064] (a) Preparation process of polyolefin resin solution

[0065] First, a molding solvent is added to a polyolefin resin, followed by melt-kneading to prepare a polyolefin resin solution. As the melt-kneading method, for example, the method using a twin-screw extruder described in JP-A-06-104736 and JP-A-3347835 can be utilized. The melt-kneading method is known, and thus its description is omitted.

[0066] The molding solvent is not particularly limited as long as it can sufficiently dissolve polyolefin. Examples thereof include aliphatic or cyclic hydrocarbons such as nonane, decane, undecane, dodecane, and liquid paraffin, or mineral oil fractions having a boiling point corresponding to these hydrocarbons, and are preferably non-volatile such as liquid paraffin. aggressive solvents.

[0067] The concentration of the polyolefin resin in the polyolefin resin solution is preferably 25 to 40 parts by weight, based on 100 parts by weight of the total amount of the polyol...

Embodiment 1

[0147] (Manufacture of polyolefin microporous membrane)

[0148] At a weight average molecular weight of 2.5×10 6 40% by mass of ultra-high molecular weight polyethylene and a weight-average molecular weight of 2.8 x 10 5 0.375 parts by mass of tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane is dry-blended in 100 parts by mass of a composition composed of 60 mass% of high-density polyethylene , produced a polyethylene composition. 30 parts by weight of the obtained polyethylene composition was put into a twin-screw extruder, and further, 70 parts by weight of liquid paraffin was supplied from the side feed port of the twin-screw extruder, and melted and kneaded to prepare a polystyrene compound in the extruder. Vinyl solution. Next, a polyethylene resin solution was extruded at 190°C from a die provided at the front end of the extruder, and was molded into an unstretched gel while being pulled by a cooling roll that kept the temperature of the int...

Embodiment 2

[0159] In addition to replacing the longitudinal stretching device A and using figure 2 A battery separator was obtained in the same manner as in Example 1 except for the longitudinal stretching device B shown.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
widthaaaaaaaaaa
widthaaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The present invention provides a battery separator in which a polyolefin microporous membrane having a width of 100 mm or more and a variation range of F25 value in the width direction of 1 MPa or less is laminated, and at least one side of the polyolefin microporous membrane is laminated. The porous layer with a uniform thickness on the surface improves the electrode adhesion, and the battery separator can be wound at a high density, which is suitable for increasing the capacity of the battery. A battery separator obtained by laminating a polyolefin microporous membrane and a porous layer comprising a fluororesin and inorganic particles on at least one side of the polyolefin microporous membrane, wherein the width of the polyolefin microporous membrane is The fluctuation range of the F25 value in the direction is 1 MPa or less, and the width of the polyolefin microporous membrane is 100 mm or more. Here, the F25 value represents a value obtained by dividing the load value when the test piece is elongated by 25% by the cross-sectional area of ​​the test piece with a tensile testing machine.

Description

technical field [0001] The present invention relates to a battery separator composed of a porous layer having electrode adhesion and a polyolefin porous film, which has a high winding density when made into a wound body and is suitable for lithium batteries with a high volume energy density. ion secondary battery. Background technique [0002] Thermoplastic resin microporous membranes have been widely used as separation membranes, permselective membranes, and isolation membranes for substances. For example, including battery separators for lithium-ion secondary batteries, nickel-hydrogen batteries, nickel-cadmium batteries, polymer batteries, separators for electric double layer capacitors, reverse osmosis filtration membranes, ultrafiltration membranes, microfiltration membranes, etc. Filters, moisture-permeable waterproof clothing, medical materials, etc. [0003] In particular, as a separator for a lithium-ion secondary battery, one that has ion permeability by impregna...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H01M50/417H01M50/426H01M50/403B32B5/32C08J9/28C08J7/043H01M50/406H01M50/451H01M50/463H01M50/491
CPCC08J9/28C08J5/18C08J9/365C08J2201/03C08J2201/0502C08J2201/0543C08J2205/02C08J2323/06C08J2427/16C08J2427/20B29K2503/04B29L2031/3468B29D7/01B29K2027/16B29C55/005B29C55/143B29K2105/041C08J7/0427B32B27/18B32B3/26B32B2307/732B32B2307/52B32B2270/00B32B2307/724B32B27/327B32B2307/518B32B7/02B32B2255/26B32B2307/306B32B7/022B32B2250/242B32B2307/304B32B27/08B32B27/32B32B2457/10B32B2255/10Y02E60/10H01M50/403H01M50/446C08J7/043H01M50/417H01M50/406H01M50/451H01M50/463H01M50/491H01M50/426H01M50/449H01M50/443H01M50/494C08J7/04B32B5/32B01D69/02B01D69/12B01D71/38B01D2325/00B01D71/40H01M10/0525
Inventor 水野直树菅田正美
Owner TORAY IND INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap