Battery pack and method of producing the same

• US 20060228623A1
• Filed: 03/31/2004
• Published: 10/12/2006
• Est. Priority Date: 06/26/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kitagawa, Toshiharu, Ebi, Ryuichiro, Masumoto, Kenjin
• Granted Patent: US 7,635,535 B2
• Time in Patent Office: Days
• US Class Current: 429/181
• CPC Class Codes: H01M 2200/106 PTC
• CPC Class Codes: H01M 50/169 by welding, brazing or soldering
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/4911 including sealing

Abstract

A battery pack having a battery in which a battery case and a cap of a sealing plate sealing an open end of the battery case serve as connection electrodes of opposite polarities, a terminal unit including external connection terminals respectively connected to these connection electrodes and an insulating cover integrally formed therewith, the terminal unit covering at least one end of the battery case, and a resilient member interposed between one end of the battery case and the terminal unit in a compressed state. In the manufacturing method of this battery pack, the dimension between the terminal unit and the other end of the battery case is controlled when fixing the terminal unit with the battery case. The battery pack thus has a simple and low cost configuration and yet exhibits high reliability in terms of the connection state of the external connection terminals when set in a portable electronic device.

Claims

1. A battery pack comprising:

a battery in which a battery case and a cap of a sealing plate sealing an open end of the battery case serve as connection electrodes of opposite polarities;

a terminal unit including external connection terminals respectively connected to these connection electrodes and an insulating cover integrally formed therewith, the terminal unit covering at least one end of the battery case; and

a resilient member interposed between one end of the battery case and the terminal unit in a compressed state.

2. The battery pack according to claim 1, wherein with the dimension between the end face of the terminal unit and the other end of the battery case being controlled, the connection electrodes and the external connection terminals are connected with one another to fix the battery case with the terminal unit.

3. The battery pack according to claim 1, wherein one of the external connection terminals has a connection leg extending from the terminal unit such as to overlap part of the outer surface of one end of the battery case and being connected to the outer surface of the battery case by welding.

4. The battery pack according to claim 3, wherein at least one gas outlet aperture is provided in the connection leg in a given location within a height range of from a welding position at which it is welded to the outer surface of the battery case and a position corresponding to the lower end of the terminal unit.

5. The battery pack according to claim 3, wherein at least one gas outlet aperture is provided in the connection leg in the vicinity of the boundary between the battery case and the lower end of the terminal unit.

6. The battery pack according to claim 3, wherein the other one of the external connection terminals and the cap are connected to each other via a lead plate that is placed inside the terminal unit.

7. The battery pack according to claim 6, wherein a PTC element or a temperature fuse is provided in the lead plate.

8. The battery pack according to claim 1, wherein one of the external connection terminals includes a layer having a different resistance from that of the external connection terminal on part of the surface thereof, and the terminal unit is integrated with the insulating cover after constituting an identification terminal portion.

9. The battery pack according to claim 1, wherein one of the external connection terminals is provided with a skin coating having a predetermined resistance on part of the surface thereof, and the terminal unit is integrated with the insulating cover after constituting an identification terminal portion.

10. The battery pack according to claim 1, wherein at least part of the terminal unit and the outer surface of the battery case are covered by a film-like outer material.

11. A method of manufacturing a battery pack having:

a battery in which a battery case and a cap of a sealing plate sealing an open end of the battery case serve as connection electrodes of opposite polarities; and

a terminal unit including external connection terminals respectively connected to these connection electrodes and an insulating cover integrally formed therewith, the terminal unit covering at least one end of the battery case, the method comprising;

interposing a resilient member between one end of the battery case and the terminal unit;

controlling the dimension between an end face of the terminal unit and the other end of the battery case while compressing the resilient member; and

connecting the connection electrodes with the external connection terminals.

12. The method of manufacturing a battery pack according to claim 11, further comprising:

connecting the cap with the other of the external connection terminals via a lead plate;

mounting the terminal unit such as to cover one end of the battery case and controlling the position of the terminal unit while compressing the resilient member; and

connecting a connection leg with an outer surface of the battery case by welding, the connection leg of one of the external connection terminals extending from the terminal unit to overlap the outer surface at one end of the battery case.

13. The method of manufacturing a battery pack according to claim 12, wherein the connection leg of the one of the external connection terminals is connected to the outer surface of the battery case by welding at a position where a reinforcing plate is placed at one end of the battery case.

14. The method of manufacturing a battery pack according to claim 11, wherein at least part of the terminal unit and the outer surface of the battery case are covered by a film-like outer material.