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:
Aug. 19, 2003
Filed:
May. 25, 2000
John Wendell Oglesbee, Watkinsville, GA (US);
Arthur G. Burns, Plantation, FL (US);
Georgina More, Lakeland, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A protection circuit ( ) and protection device ( ) for protecting a rechargeable (lithium-based) battery cell or cells from overcharging. A voltage regulator element ( ) is connected in parallel with the battery cell or cells ( ) and is thermally coupled to a thermal element ( ) connected in series with the charging current supply. The voltage regulator element ( ) prevents overcharging of the battery ( ) by shunting current away from the battery when a predetermined voltage across the battery is exceeded. Moreover, the thermal element ( ) prevents failure of the voltage regulator element ( ) by open circuiting the current path when the heat dissipated by the voltage regulator element ( ), thermally coupled to the thermal element ( ) causes the thermal element to enter a high resistance state. Additional protection may be provided by fuse bonds ( ) connecting the combination of the shunt voltage regulator and the thermal elements ( ) to the charging current supply and to the battery ( ).