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:
Jul. 04, 2000
Filed:
Sep. 18, 1998
Seiji Takeuchi, Hitachiota, JP;
Hidetoshi Honbo, Hitachi, JP;
Takeo Yamagata, Takahagi, JP;
Tatsuo Horiba, Hitachi, JP;
Yasushi Muranaka, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A lithium secondary battery suitable for use as a power source for a secondary battery using system such as an electric automobile, motor bicycle or portable equipment includes a negative electrode (17) composed of a carbon material including carbon particles carrying fine particles of a metal which forms an alloy with lithium. The carbon particles have a face-to-face dimension which is 3.354 to 3.369 .ANG. and a crystal grain size in a C-axis direction which is equal to or greater than 300 .ANG.. The metal forming an alloy with lithium has a particle size which is equal to or smaller than 1000 .ANG.. With the use of the charge/discharge capacity of an alloy of the metal and lithium, a value exceeding the theoretical capacity 372 mAh/g of graphite can be obtained. The lithium secondary battery is capable of discharge with an output energy density equal to or higher than 350 W/kg.