PROTECTIVE ELEMENT AND SECONDARY BATTERY DEVICE

• US 20110012704A1
• Filed: 05/14/2009
• Published: 01/20/2011
• Est. Priority Date: 05/23/2008
• Status: Active Grant

• Current Assignee: Dexerials Corporation
• Original Assignee: Sony Chemical & Information Device Corporation (Sony Group Corp.)
• Inventors: Asada, Takahiro, Kimura, Yuji, Suzuki, Kazuaki, Yoneda, Yoshihiro
• Granted Patent: US 8,547,195 B2
• Time in Patent Office: Days
• US Class Current: 337/168
• CPC Class Codes: H01H 2085/466 with remote controlled forced fusing
• CPC Class Codes: H01H 37/761 with a fusible element forming part of the switched circuit H01H37/767 takes precedence
• CPC Class Codes: H01H 61/02 wherein the thermally-sensitive member is heated indirectly, e.g. resistively, inductively
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• 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 50/583 in response to current, e.g. fuses
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49107 Fuse making

Abstract

A protection element and a secondary battery device employing the protection element are provided for stably retaining a flux on a soluble conductor at a predetermined position, so as to enable appropriate blowout of the soluble conductor in the event of an abnormality. The protection element has a soluble conductor which is disposed on an insulation baseboard, and which is connected to a power supply path of a device targeted to be protected, and which causes a blowout when a predetermined abnormal electric power, amount is supplied. A flux is coated on a surface of the soluble conductor, and an insulation cover member is mounted on the baseboard and covers the soluble conductor. The protection element also includes a stepped portion for retaining the flux at a predetermined position in contact with the flux, and the stepped portion is formed opposite to the soluble conductor on an interior face of the insulation cover member.

Claims

1. A protection element comprising:

a soluble conductor which is disposed on an insulation baseboard, which is connected to a power supply path of a device targeted to be protected, and which causes a blowout when a predetermined abnormal electric power amount is supplied;

an insulation cover member which is mounted on the baseboard, and which covers the soluble conductor with a predetermined space; and

a flux coated on a surface of the soluble conductor and positioned in the space;

wherein, in a case where the abnormal electric power amount is supplied to the device targeted to be protected, the soluble conductor causes the blowout, and a current path thereof is shut off; and

wherein said protection element comprises a stepped portion which is formed on an interior face of the insulation cover member opposite to the soluble conductor, for retaining the flux at a predetermined position in the space in contact with the flux.

2. The protection element as set forth in claim 1, wherein:

the stepped portion is formed by a protrusion formed on the interior face of the insulation cover member.

3. The protection element as set forth in claim 1, wherein:

the stepped portion comprises a protrusive stripe formed in a circular shape such that a center part of the soluble conductor is surrounded by the interior face of the insulation cover member.

4. The protection element as set forth in claim 3, wherein:

the stepped portion comprises a protrusive stripe formed in a cylindrical shape such that the center part of the soluble conductor is surrounded by the interior face of the insulation cover member.

5. The protection element as set forth in claim 1, wherein:

the stepped portion is formed by a recessed portion formed on the interior face of the insulation cover member.

6. The protection element as set forth in claim 1, wherein:

the stepped portion is formed by a polygonal protrusion formed on the interior face of the insulation cover member.

7. The protection element as set forth in claim 1, wherein:

when the soluble conductor causes the blowout, an end face at a side of the soluble conductor of the stepped portion is provided at a position at which a top part of the blowout soluble conductor does not come into contact.

8. The protection element as set forth in claim 1, wherein:

a protrusion opposite to the stepped portion is provided at an end of the soluble conductor.

9. The protection element as set forth in claim 1, wherein:

the stepped portion comprises an opening of a through hole formed in the insulation cover member.

10. The protection element as set forth in claim 9, wherein:

a plurality of the openings are formed in the insulation cover member.

11. The protection element as set forth in claim 3, wherein:

a cutout portion communicating with a space at a back side of the insulation cover member is formed in the protrusive stripe.

12. The protection element as set forth in claim 11, wherein:

the cutout portion is provided at a position which is symmetrical to a center axis of the insulation cover member.

13. The protection element as set forth in claim 1, wherein:

a heating element is laminated on the baseboard via an insulation layer;

the soluble conductor and the heating element are connected between a plurality of electrodes formed on the baseboard; and

a number of the electrodes formed on the baseboard is three or less.

14. The protection element as set forth in claim 1, wherein:

with respect to a size of the baseboard, dimensional ratios thereof meet a condition that a length to thickness ratio is 1080%;

50 to 78% and a width to thickness ratio is 640%;

50 to 78%.

15. The protection element as set forth in claim 14, wherein:

the dimensional ratios meet a condition that a length to thickness ratio is 1080%;

50 to 78% and a width to thickness ratio is 640%;

50 to 56%.

16. A secondary battery device, wherein:

the protection element as set forth in claim 1 is provided in a power supply path of a secondary battery.