The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 07, 2008
Filed:
Sep. 14, 2004
Yoshihiro Dokko, Fukushima, JP;
Yoshihiro Dokko, Fukushima, JP;
Sony Corporation, Tokyo, JP;
Abstract
A battery, which can inhibit raise of an internal resistance even when temperature change or mechanical shock is applied, and which has superior productivity is provided. A safety mechanism and a battery cover are installed at an open part of a battery case by caulking through a gasket. Inside of the battery case is sealed. A flange part of the battery cover contacts with a flange part of a safety valve of the safety mechanism. A surface roughness of the contact face is set to be in the range from about 0.5 μm to about 5.5 μm based on an arithmetic average roughness Ra. A contact resistance between the battery cover and the safety valve is thereby reduced. Further, a maximum height Ry of the contact face is preferably in the range from about 8.0 μm to about 50.0 μM.