Patent · US Expired

Battery charging, monitoring and alarm circuit

US4916438A · kind A · utility

25Cited by
20References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 4, 1989
Grant dateApr 10, 1990
Priority date
Expiry dateMay 4, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/392
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Methods and circuits are provided for monitoring a battery with the monitored battery electrically connected in an operating system. A dynamic impedance characteristic of the monitored battery is identified and compared with a predefined value. An alarm signal is generated responsive to the compared values to predict a degraded battery capacity. A leakage current value through the monitored battery is detected. An alarm signal is generated responsive to the detected leakage current value to predict a short life expectancy for the monitored battery. Visual and audible alarms are generated responsive to either of the generated alarm signals after the monitored battery has been fully charged. An alarm signal is immediately generated responsive to a detected charging current value above a predetermined value.

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