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:
Feb. 17, 2009
Filed:
Dec. 08, 2005
Alex Fresard, Encinitas, CA (US);
Robert Crawford, Murrieta, CA (US);
Alex Fresard, Encinitas, CA (US);
Robert Crawford, Murrieta, CA (US);
Maxwell Technologies, Inc., San Diego, CA (US);
Abstract
Porous separator is sandwiched between electrode films with attached current collector foil to obtain an electrode sheet. The electrode sheet is formed into a jellyroll for use in a double layer capacitor. The jellyroll is inserted into a can through an open end to rest against the can's bottom. A collector plate is pressed against the jellyroll, crunching current collector foil protruding from each end of the jellyroll. The bottom and the collector plate include indentations of reduced thickness. Laser is applied to the indentations to weld the foil on each end of the jellyroll to the bottom or collector plate. The laser application pattern, for example, a zigzag pattern, results in the total length of laser welds along each indentation being considerably longer than the length of the indentation, reducing contact resistance between (1) the foil and the bottom, and (2) the foil and the current collector.