BATTERY PACK AND PORTABLE ELECTRONIC DEVICE

• US 20080220321A1
• Filed: 03/10/2008
• Published: 09/11/2008
• Est. Priority Date: 03/09/2007
• Status: Active Grant

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Inventors: Yonemochi, Kenshin, Horikoshi, Seita
• Granted Patent: US 7,851,079 B2
• Time in Patent Office: Days
• US Class Current: 429/89
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/3425 in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention includes a plurality of battery cells, each provided with a gas discharge valve. A housing accommodates the battery cells and has a gas opening. The housing does not melt at an inside temperature of the battery pack increased by gas discharged from the gas discharge valve. A blocking member blocks the gas opening and melts at the inside temperature of the battery pack increased by the gas discharged from the gas discharge valve, breaching the gas opening.

Claims

1. A battery pack comprising:

a plurality of battery cells each provided with a gas discharge valve;

a housing, which accommodates therein the battery cells and has a gas opening, the housing not melting at an inside temperature of the battery pack increased by gas discharged from the gas discharge valve; and

a blocking member which blocks the gas opening and melts at the inside temperature of the battery pack increased by the gas discharged from the gas discharge valve, breaching the gas opening.

2. The battery pack according to claim 1, wherein the housing is in a sealed state when the gas opening is blocked.

3. The battery pack according to claim 1,

wherein the housing is formed of a material selected from a magnesium alloy and an aluminum alloy;

and

the blocking member is formed of a synthetic resin.

4. The battery pack according to claim 3, wherein the synthetic resin is molded in the shape of the gas opening and is bonded to the housing by a bondant selected from an adhesive and a weld.

5. The battery pack according to claim 3, wherein the blocking member is formed with a thin-walled portion.

6. The battery pack according to claim 1,

wherein the gas opening is formed in the housing in a plural number;

and

the sum of areas of the gas openings is at least one percent of the surface area of the housing.

7. The battery pack according to claim 1,

wherein the housing comprises an upper housing and a lower housing;

and

the gas opening is formed along a fitting portion of the upper housing and the lower housing.

8. The battery pack according to claim 7,

wherein the gas opening is formed in a shape of a slit in a plural number;

and

a total length of the plural number of gas openings is at least fifty percent of a length of the fitting portion.

9. The battery pack according to claim 1,

wherein the housing comprises an upper housing and a lower housing;

and

the gas opening is formed on a bottom surface selected from a bottom surface of the upper housing and a bottom surface of the lower housings.

10. The battery pack according to claim 9, wherein the gas opening is formed in the shape of a mesh.

11. The battery pack according to claim 9,

wherein the plurality of battery cells include a row of battery cells connected in series;

and

the gas opening is formed along the row of battery cells on a bottom surface of the upper housing.

12. The battery pack according to claim 1, wherein the housing forms a part of an outline of a body of a portable electronic device when the battery pack is mounted in the portable electronic device.

13. The battery pack according to claim 1, wherein the housing includes an extending portion located outside an outline of a body of a portable electronic device when the battery pack is mounted in the portable electronic device.

14. The battery pack according to claim 1,

wherein the battery pack is housed in a battery bay of a portable electronic device;

and

the gas opening is formed on a surface of the housing opposite a side wall of the battery bay.

15. A portable electronic device comprising:

a battery bay housing a battery pack;

the battery pack comprising

a plurality of battery cells, each being provided with a gas discharge valve;

a housing accommodating therein the plurality of battery cells and with a gas opening, the housing not melting at an inside temperature of the battery pack increased by gas discharged from the gas discharge valve; and

a blocking member which blocks the gas opening and melts at the inside temperature of the battery pack increased by the gas discharged from the gas discharge valve, breaching the gas opening.

16. The portable electronic device according to claim 15, father comprising an opening in a side wall of the battery bay for discharging gas.