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:
Apr. 04, 2017
Filed:
Dec. 09, 2011
Masayuki Kouzu, Hitachi, JP;
Kento Hoshi, Hitachi, JP;
Toshikatsu Shimazaki, Hitachi, JP;
HITACHI CHEMICAL COMPANY, LTD., Tokyo, JP;
Abstract
The invention provides a negative electrode material for lithium ion secondary battery, including a composite particle of a first particle containing a carbonic substance A and a second particle containing silicon, which are combined with a carbonic substance B, wherein, when a cross-section of the composite particle is observed with respect to: the content of silicon atom in a core region in a circle having a center thereof on the midpoint of the major axis, which constitutes the maximum length, and having a radius of ⅛ of the length of the minor axis orthogonally intersecting the major axis at the midpoint thereof, and the content thereof in a rim region extending from the circumference to a depth of ⅛ of the length of the minor axis, the ratio of the content in the rim region to that in the core region is 2 or higher.