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:
Nov. 09, 1993
Filed:
Oct. 21, 1992
Minoru Hirahara, Kawasaki, JP;
Fujitsu Limited, , JP;
Abstract
A quick charging method of secondary cell in which a secondary cell is prevented from being damaged on account of overcharging. A strain gage is bonded to the side face of a cell to be charged. A low resistor for quick charging and a high resistor for normal charging connected in parallel are inserted between a charger and the cell. The low resistor for quick charging is connected with the contact of a normally open contact relay. A voltage for measurement is generated according to the resistance of the strain gage and this voltage for measurement is compared with a reference voltage. The relay is ON/OFF controlled by the result of the comparison. Since the resistance of the strain gage is low in the beginning stage of charging, a high voltage for measurement is generated and, thereby, the relay is energized and the contact is closed so that quick charging is performed. When the cell is fully charged, the resistance of the strain gage increases and, thereby, the relay is turned OFF and the quick charging mode is switched to the normal charging mode.