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:
Sep. 10, 2002
Filed:
Apr. 05, 2000
Toyo Aluminum Kabushiki Kaisha, Osaka, JP;
Abstract
A collector for a secondary battery includes a metal foil having throughholes shaped or arranged to achieve an increased hole area ratio to improve an active material's adhesion thereto. A throughhole in the metal foil has a largest dimension of at least 1.55 mm, and the foil has a hole area ratio of at least 40%, and a thickness of at least 5 &mgr;m and at most 200 &mgr;m. The throughhole has a peripheral shape including two substantially straight sides that extend along lines intersecting with each other on their respective extensions to form an acute angle at a corner of the throughhole. To form the metal foil, a resist film with a predetermined pattern is arranged on a solid foil, and is used as a mask to etch the foil to provide the plurality of throughholes penetrating the foil.