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:
Feb. 02, 1999
Filed:
Jun. 03, 1997
Xin Du, Bartlett, IL (US);
Edward F Bachner, III, Lockport, IL (US);
Double-Time Battery Corporation, Lockport, IL (US);
Abstract
A self-contained, rechargeable battery pack uses a coulomb-counting control circuit to measure charge received by and taken from the cells and to store a current charge status of those cells. The control circuit controls a charge/discharge pass transistor in the pack to provide overcharge protection. An always-on trickle charge resistor insures that the controller is in operation during charging even when the cells associated with the controller are completely discharged. A Schottky diode is placed across the charge/discharge pass transistor in order to minimize the discharge dropoff voltage between the terminal of the cell and a corresponding external terminal. The present invention considerably lengthens the useful life of nickel-based rechargeable batteries, as measured in terms of both the number of cycles and the available capacity per cycle, while requiring no extra terminals.