Battery separator assembly

• US 4,741,979 A
• Filed: 05/19/1986
• Issued: 05/03/1988
• Est. Priority Date: 05/19/1986
• Status: Expired due to Term

• Current Assignee: Ultralife Batteries Incorporated
• Original Assignee: Eastman Kodak Company
• Inventors: Faust, Marilyn A., Suchanski, Mary R., Osterhoudt, Hans W.
• Primary Examiner(s): Niebling, John F.
• Assistant Examiner(s): Marquis, Steven P.
• Application Number:
  US06/864,376
• Time in Patent Office: 715 Days
• Field of Search: 429/62, 429/142, 429/144, 429/248, 429/249, 429/194, 429/197
• US Class Current: 429/144
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: H01M 2200/00 Safety devices for primary or secondary batteries
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 50/414 Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: H01M 50/454 comprising a non-fibrous layer and a fibrous layer superimposed on one another
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A separator assembly for use in batteries comprising a film bearing a thermal fuse in the form of a layer of wax coated fibers is disclosed.

Claims

1. A separator assembly for use in batteries comprising a film bearing a thermal fuse in the form of a layer of wax coated fibers;

wherein said assembly is sufficiently porous to allow continuous flow of ions in the battery.

2. The separator assembly of claim 1 wherein both the film and the thermal fuse is porous.

3. The separator assembly of claim 2 or 1 wherein the film is microporous.

4. The separator assembly of claim 2 or 1 wherein the wax has a melting point of 50°

to 150°

C.

5. The separator assembly of claim 2 or 1 wherein the wax is selected from the group consisting of

(a) a mixture of paraffin and a thermoplastic polymer,

(b) beeswax,

(c) microcrystalline wax,

(d) candellila wax,

(e) rice bran wax,

(f) polyethylene wax, and

(g) polypropylene wax.

6. A battery comprising an anode, a cathode, an electrolyte and a separator assembly between the anode and the cathode;

wherein the separator assembly (a) comprises a film bearing a thermal fuse in the form of a layer of wax coated fibers and (b) is sufficiently porous to allow continuous flow of ions in said battery.

7. The battery of claim 6 comprising a lithium anode.

8. The battery of claim 6 comprising a MnO₂ cathode.

9. The battery of claim 7, 8 or 6 wherein the separator assembly is porous.

10. The battery of claim 7, 8, 9 or wherein the wax is selected from the group consisting of

(a) a mixture of paraffin and a thermoplastic polymer,

(b) beeswax,

(c) microcrystalline wax,

(d) candellila wax,

(e) rice bran wax,

(f) polyethylene wax, and

(g) polypropylene wax.

11. The battery of claim 7, 8, 9 or 6 wherein the wax has a melting point in the range of 50°

to 150°

C.

12. A battery comprising a lithium anode, an MnO₂ cathode, an electrolyte comprising 1M LiBF₄ in a solvent mixture of butyrolactone and dimethoxyethane and a separator assembly between the anode and cathode;

wherein the separator assembly comprises a porous film bearing a thermal fuse in the form of a porous layer of wax coated fibers.

13. A battery comprising a lithium anode, an MnO₂ cathode, an electrolyte comprising 1M LiCF₃ SO₃ in a solvent mixture of butyrolactone and dimethoxyethane and a separator assembly between the anode and the cathode;

wherein the separator assembly comprises a porous film bearing a thermal fuse in the form of a porous layer of wax coated fibers.