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:
Oct. 28, 2003
Filed:
Oct. 31, 2002
Nobuo Shiojima, Tokyo, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Abstract
A rechargeable battery device includes battery voltage detection means which detects the terminal voltage of a rechargeable battery comprising a nickel hydride metal battery and switching means which switches on and off the charging current of the rechargeable battery continuously or intermittently. A value corresponding to the internal resistance R of the rechargeable battery is determined from the battery voltage Von immediately before the charging current is switched off and the open battery voltage Voff after the charging current is switched off. The value Z(int) corresponding to the early-stage internal resistance R of the rechargeable battery and the value Z(now) corresponding to the latest internal resistance R of the rechargeable battery are compared to determine the operation life of the rechargeable battery.