Panasonic Corporation

Kouki Inoue

Tatsuya Hashimoto

Yasushi Hirakawa

Kiyomi Kozuki

Kiyomi Kouzuki

In a secondary battery () comprising a battery case () for accommodating an electrode plate group () and an electrolyte, with one open end of the battery case () being sealed with an assembled sealing plate () that accommodates a safety mechanism () for exhausting pressure in the event of pressure build-up in the battery case () exceeding a predetermined level, at least one part () of vent holes () in the assembled sealing plate () facing the inside of the battery case () is constituted of an aperture that results from formation of a turned-out portion (), the distal end of the turned-out portion () being allowed to abut on an insulating plate () that makes contact with one end of the electrode plate group () so as to restrict movement of the electrode plate group (). This can prevent malfunctioning due to displacement of the electrode plate group () when an impact or vibration is applied.

Secondary battery with improved shock resistance

In a closure assembly for sealed rechargeable batteries, upon a metallic foil is placed a spacer having an aperture that is larger than an upwardly protruding portion of the foil but smaller than the outside diameter of the foil, and upon a metallic safety vent is placed either a spacer and a metallic cap, or a metallic cap only, the spacer and/or metallic cap having an aperture that is larger than a downwardly protruding portion of the safety vent but smaller than the outside diameter of the safety vent, so as to control and suppress deformation of the metallic foil and safety vent in the event of abnormal battery pressure increasing due to overcharging or the like and to ensure that rupture occurs at a predetermined pressure level, whereby a sealed rechargeable battery suitable for high-output applications and having high safety features is provided.

Growing community of inventors

Osaka, Japan

Kouki Inoue