Multi-region battery separators
AssigneeHollingsworth & Vose Company
InventorsAkshay Ashirgade, Zhiping Jiang
Life of this patent
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Abstract
Disclosed is a battery separator, comprising two fiber regions comprising glass fibers, and a middle fiber region disposed between them comprising larger average diameter fibers and specified amounts of silica, or fine fibers, or both; and processes for making the separator. Also disclosed is a battery separator, comprising a fiber region and either one or two silica-containing region(s) adjacent thereto, each of the regions containing a specified amount of silica; and processes for making the separator. Such separators are useful, e.g., in lead-acid batteries.
Claims20
A battery separator, comprising:
- a middle fiber region;
- a first peripheral fiber region;
- and
- a second peripheral fiber region;
- wherein the middle fiber region comprises fibers having an average diameter of greater than or equal to about 2 μm;
- and
- wherein each of the first and second peripheral fiber regions independently comprises glass fibers having an average diameter from about 0.1 to about 2 μm;
- provided that the average diameter of the fibers of the middle fiber region is larger than the average diameter of the fibers of each of the first and second peripheral fiber regions;
- wherein the middle fiber region is disposed between the first peripheral fiber region and the second peripheral fiber region;
- wherein the thickness of the middle fiber region constitutes 1-49% of the total fiber region thickness;
- and
- wherein the thickness of the first peripheral fiber region is different from the thickness of the second peripheral fiber region.
A battery separator, comprising:
- a middle fiber region;
- a first peripheral fiber region;
- and
- a second peripheral fiber region;
- wherein the middle fiber region comprises fibers having an average diameter of greater than or equal to about 2 μm;
- and
- wherein each of the first and second peripheral fiber regions independently comprises glass fibers having an average diameter from about 0.1 to about 2 μm;
- provided that the average diameter of the fibers of the middle fiber region is larger than the average diameter of the fibers of each of the first and second peripheral fiber regions;
- wherein the middle fiber region is disposed between the first peripheral fiber region and the second peripheral fiber region;
- wherein the thickness of the middle fiber region constitutes 1-49% of the total fiber region thickness;
- wherein the thickness of the first peripheral fiber region is different from the thickness of the second peripheral fiber region;
- and
- wherein formation of the battery separator involves a process comprising:
- (a) providing a first slurry of fibers having an average diameter from about 0.1 μm to about 2 μm;
- (b) laying down the first slurry on a wire of a papermaking machine;
- (c) providing a second slurry of fibers having an average diameter of greater than or equal to about 2 μm;
- (d) laying down the second slurry on top of the first slurry;
- and
- (e) dewatering the first and second slurries to form a 2-layer structure comprising the first peripheral region and at least a portion of the middle fiber region.
A battery separator, comprising:
- a middle fiber region;
- a first peripheral fiber region;
- a second peripheral fiber region, wherein the first and second peripheral regions are different from the middle fiber region;
- means for the battery separator exhibiting an acid filling time of about 17 to about 155 seconds;
- and
- means for the battery separator exhibiting an acid stratification distance of from about 2.5 to about 16 cm.
Dependencies are inferred from the claim text.