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. 30, 2002
Filed:
Mar. 08, 2001
Yusai Murakami, Shizuoka, JP;
Tadao Kimura, Hyogo, JP;
Toshiaki Nakanishi, Aichi, JP;
Toshihiro Katsuda, Aichi, JP;
Yoshiaki Kikuchi, Aichi, JP;
Other;
Abstract
A device and method is provided that can detect overcharge reliably by separating heat generated by internal resistance and heat chemically generated upon overcharging in a secondary battery. Based on the temperature of the secondary battery detected every first predetermined time by a battery temperature detection section, a temperature gradient operation section calculates a temperature gradient indicating a temperature increase per unit time for every second predetermined time that is longer than the first predetermined time. When a temperature gradient determination section determines that the temperature gradient is larger than a predetermined temperature gradient threshold, which is preset according to the charged state of the secondary battery, N times in a row (where N is a natural number), a fully charged state of the secondary battery is detected.