Patent · US Expired

Battery charger circuit including battery temperature control

US5504416A · kind A · utility

39Cited by
45References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 15, 1993
Grant dateApr 2, 1996
Priority date
Expiry dateDec 15, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An adaptive battery charger circuit including a state machine adjusts the charging current in accordance with the battery charge acceptance. The battery charging cycle includes an initial charging phase characterized by a relatively high charge acceptance, an intermediate charging phase characterized by a decreasing charge acceptance and a rising battery temperature, and a final charging phase characterized by the battery being at substantially full charge and the charge acceptance approaching zero. Each charging phase corresponds to one or more states of the state machine. Multiple sets of conditions causing transitions between the states of operation are derived from a model of a battery under charge which relates charge acceptance, battery temperature, and cumulative supplied charge. During the intermediate charging phase, the charging current is adjusted to maintain a predetermined battery temperature for a predetermined duration. With this arrangement, the maximum product of charging current and charge acceptance maintainable for the battery without exceeding a safe temperature is continuously achieved.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.