Separator for lead acid storage battery

Patent metadata

Field	Value
Publication number	US-11158908-B2
Application number	US-201816606710-A
Country	US
Kind code	B2
Filing date	Apr 27, 2018
Priority date	Apr 28, 2017
Publication date	Oct 26, 2021
Grant date	Oct 26, 2021

Abstract

[Problem]A separator for a lead acid storage battery that is prevented from suffering the puncture of a separator formed of a microporous film is to be provided.[Solution]The separator includes: a microporous film having a thickness of from 0.1 to 0.3 mm as a base portion 3; plural main ribs 2a that are provided on one surface 3a of the base portion 3; and plural miniature ribs 2b that have a lower height than a height of the main ribs 2a and are provided on the other surface 3b of the base portion 3, and the plural miniature ribs 2b are provided in a linear form with an inter-rib distance P, which is a distance between facing surfaces of the adjacent miniature ribs 2b, of less than 1.9 mm.

First claim

The invention claimed is:

1. A separator for a lead acid storage battery, comprising:
a microporous film having a thickness of from 0.1 to 0.3 mm as a base portion;
plural main ribs that are provided on one surface of the base portion; and
plural miniature ribs that have a lower height than a height of the main ribs and are provided on the other surface of the base portion for contacting a lead portion of an electrode plate,
the plural miniature ribs being provided in a linear form with an inter-rib distance, which is a distance between facing surfaces of the adjacent miniature ribs, of less than 1.9 mm,
wherein the miniature ribs have an inclination to the flow direction of the sheet, the inclination angle being 30° or less.

2. The separator for a lead acid storage battery according to claim 1 , wherein in a case where a contact width of a tip surface having a diameter of 1.9 mm of a needle to the miniature rib in a cross section perpendicular to the linear direction of the miniature rib is changed while repeatedly increasing and decreasing at a constant cycle by perpendicularly touching the miniature rib of the other surface with the tip surface of the needle and moving the needle along a direction of the inter-rib distance, a probability of contacting the tip surface of the needle with the miniature rib is 10% or more and 30% or less, and
the probability is determined from a ratio of a width of the miniature rib that is brought into contact with the needle to a width of the tip surface of the needle while the needle moves for one cycle of the cycle.

3. The separator for a lead acid storage battery according to claim 1 , wherein the miniature ribs have a miniature rib height of from 0.05 to 0.20 mm.

4. The separator for a lead acid storage battery according to claim 1 , wherein the base portion has a thickness of from 0.15 to 0.25 mm.

5. The separator for a lead acid storage battery according to claim 1 , wherein the miniature ribs are provided in a linear form in a direction in parallel to a flow direction of a sheet in compression molding in production of the microporous film.

Assignees

• Nippon Sheet Glass Co Ltd

Inventors

• Onishi Masaki
• Shidomi Takashi
• Kawachi Masahiro

Classifications

• H01M10/06 Primary

  Lead-acid accumulators (semi-lead accumulators H01M10/20) · CPC title

• H01M50/463 Primary

  Separators, membranes or diaphragms characterised by their shape · CPC title

• H01M50/417

  Polyolefins · CPC title

• H01M50/406

  Moulding; Embossing; Cutting · CPC title

• H01M50/40 Primary

  Separators; Membranes; Diaphragms; Spacing elements inside cells · CPC title