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. 28, 2015
Filed:
Jul. 20, 2011
Jiro Iriyama, Tokyo, JP;
Tetsuya Kajita, Tokyo, JP;
Daisuke Kawasaki, Tokyo, JP;
Ryuichi Kasahara, Tokyo, JP;
Tatsuji Numata, Tokyo, JP;
Jiro Iriyama, Tokyo, JP;
Tetsuya Kajita, Tokyo, JP;
Daisuke Kawasaki, Tokyo, JP;
Ryuichi Kasahara, Tokyo, JP;
Tatsuji Numata, Tokyo, JP;
NEC Corporation, Tokyo, JP;
NEC Energy Devices, Ltd., Kanagawa, JP;
Abstract
There is provided a control system for a lithium secondary battery that can quantitatively sense a deterioration state inherent in a lithium secondary battery using silicon oxide as a negative electrode active material, that is, the nonuniform reaction state of a negative electrode. A control system for a lithium secondary battery including a positive electrode, a negative electrode using silicon oxide as a negative electrode active material, and a lithium reference electrode having a reference potential with respect to the negative electrode includes measurement means for measuring a voltage V of the negative electrode with respect to the lithium reference electrode and a discharge capacity Q of the lithium secondary battery during discharge of the lithium secondary battery; generation means for generating a V-dQ/dV curve representing a relationship between dQ/dV, which is a proportion of an amount of change dQ in the discharge capacity Q to an amount of change dV in the voltage V, and the voltage V; calculation means for calculating an intensity ratio of two peaks appearing on the V-dQ/dV curve for two voltage values in the voltage V; and sensing means for sensing a state of the negative electrode utilizing the intensity ratio.