Battery separators having a low apparent density

Patent metadata

Field	Value
Publication number	US-10014501-B2
Application number	US-201515127057-A
Country	US
Kind code	B2
Filing date	Mar 20, 2015
Priority date	Mar 22, 2014
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

In some embodiments, a battery separator described herein may comprise a layer having a relatively low apparent density; for example, the density that includes any unoccupied space within the outermost boundaries of the layer may be relatively low. The low apparent density may be attributed to, at least in part, the geometry of the layer. For instance, in some embodiments, the layer may include undulations and/or have at least one non-planar surface (e.g., a corrugated layer; an embossed layer). In some embodiments, a battery comprising a layer having a relatively low apparent density may have desirable properties, including relatively low electrical resistance and/or relatively high capacity. The battery separators described herein may be well suited for a variety of battery types, including lead acid batteries.

First claim

What is claimed is:

1. A battery separator, comprising:
a first non-woven web comprising:
a plurality of glass fibers having an average diameter of greater than or equal to about 0.1 microns;
a plurality of synthetic fibers, wherein the synthetic fibers are present in an amount of greater than or equal to about 1 wt. % and less than or equal to about 80 wt. % of the first non-woven web; and
a plurality of inorganic particles, wherein the inorganic particles are present in an amount of greater than or equal to about 10 wt. % and less than or equal to about 80 wt. % of the first non-woven web; and

an additional layer adjacent the first non-woven web, wherein the additional layer is a second non-woven web comprising glass fibers, and wherein the additional layer is corrugated, embossed, pleated, creped, or micrexed.

2. A battery separator as in claim 1 , wherein the first non-woven web has undulations.

3. A battery separator as in claim 1 , wherein the first non-woven web is corrugated, embossed, pleated, creped, and/or micrexed.

4. A battery separator as in claim 1 , wherein an apparent density of the first non-woven web is greater than or equal to about 40 g/m 2 /mm and less than or equal to about 250 g/m 2 /mm.

5. A battery separator as in as in claim 1 , wherein an apparent density of the battery separator is greater than or equal to about 40 g/m 2 /mm and less than or equal to about 200 g/m 2 /mm.

6. A battery separator as in claim 1 , wherein the additional layer has an apparent density of greater than or equal to about 40 g/m 2 /mm and less than or equal to about 300 g/m 2 /mm.

7. A battery separator as in claim 1 , wherein the synthetic fibers are present in an amount of greater than or equal to about 5 wt. % and less than or equal to about 50 wt. % of the first non-woven web.

8. A battery separator as in claim 1 , wherein the inorganic particles are resistant to sulfuric acid, and wherein the inorganic particles are present in an amount of greater than or equal to about 30 wt. % and less than or equal to about 60 wt. % of the non-woven web.

9. A battery separator as in claim 1 , wherein first non-woven web further comprises a binder resin.

10. A battery separator as in claim 1 , wherein a volume porosity of the battery separator is greater than or equal to about 80% and less than or equal to about 98%.

11. A battery separator as in claim 1 , wherein the battery separator is a lead acid battery separator.

12. A battery separator as in claim 1 , wherein an apparent density of the first non-woven web is greater than or equal to about 80 g/m 2 /mm and less than or equal to about 150 g/m 2 /mm.

13. A battery separator as in claim 1 , wherein the inorganic particles have a surface area of greater than or equal to about 100 m 2 /g and less than or equal to about 600 m 2 /g.

14. A battery separator as in claim 1 , wherein a thickness of the battery separator is greater than or equal to about 0.1 mm and less than or equal to about 3 mm.

15. A battery separator as in claim 1 , wherein a pore size of the battery separator is greater than or equal to about 0.2 microns and less than or equal to about 30 microns.

16. A battery separator as in claim 1 , wherein a puncture strength of the battery separator is greater than or equal to about 1.5 N and less than or equal to about 15 N.

17. A battery separator as in claim 1 , wherein a tensile strength of the battery separator is greater than or equal to about 15 kg/cm 2 and less than or equal to about 60 kg/cm 2 .

18. A lead acid battery comprising the battery separator of claim 1 .

19. A battery separator as in claim 1 , wherein the first non-woven web comprises a plurality of indentations, and wherein a percent surface area of the first non-woven web that is indented is greater than or equal to about 20%.

Assignees

• Hollingsworth & Vose Co

Inventors

• Natesh Gubbi Krishnappa
• Marchigowda Krishna
• Girisha Basavaraju
• Patchigolla Venkata Kameswara Rao
• Clement Nicolas
• Ashirgade Akshay
• Kumar Sachin
• Wertz John A
• Angus Jr Richard O
• Jiang Zhiping

Classifications

• H01M50/414

  Synthetic resins, e.g. thermoplastics or thermosetting resins · CPC title

• H01M50/457

  comprising three or more layers · CPC title

• H01M50/494

  Tensile strength · CPC title

• H01M50/491

  Porosity · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title