Patent · US Expired

Apparatus and method for charging batteries

US5365160A · kind A · utility

204Cited by
10References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 6, 1991
Grant dateNov 15, 1994
Priority date
Expiry dateSep 6, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J7/0024
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A charging system monitors the rate of change in battery voltage, adjusts the rate of charging, and checks the changes in battery voltage following adjustments in the rate of charging to observe a predetermined sequence of voltage changes that signifies when a battery is fully charged. The charging system determines the slope between consecutive battery voltage measurements. The charging system charges a battery at the full battery capacity in response to positive or zero voltage slope measurements and reduces the charging rate in response to negative voltage slope measurements. A nickel-cadmium battery is fully charged when at least one sequence of a negative slope, followed by a decrease in charging rate, then a positive or flat slope, followed by an increase in charge rate, and finally another negative slope is observed.

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