Multi-layer, microporous membrane, battery separator and battery
AssigneeToray Battery Separator Film Co., Ltd.
InventorsKoichi Kono, Kohtaro Kimishima, Hiroyuki Ozaki, Patrick Brant, Jeffrey L. Brinen, Zerong Lin
Life of this patent
Estimating the term…
Abstract
The invention relates to a multi-layer, microporous membrane having appropriate permeability, pin puncture strength, shutdown temperature, shutdown speed, meltdown temperature, and thickness uniformity. The invention also relates to a battery separator formed by such multi-layer, microporous membrane, and a battery comprising such a separator. Another aspect of the invention relates to a method for making the multi-layer, microporous polyolefin membrane, a method for making a battery using such a membrane as a separator, and a method for using such a battery.
Claims14
A multi-layer microporous membrane, comprising:
- a first layer material comprising a first polyethylene and a first polypropylene having a weight-average molecular weight of 3.0×105 to 1.40×106 and a second layer material comprising a second polyethylene and a second polypropylene consisting of a propylene homopolymer, the second polypropylene having a weight-average molecular weight of 0.90×106 to 2.69×106 and a heat of fusion of 95 J/g or more the fraction of the second polypropylene having a molecular weight of 1.8×106 or more being 10% or more by mass of the second polypropylene and the first and second polypropylenes have different weight-average molecular weights.
Dependencies are inferred from the claim text.