Accession Number : ADD003760

Title :   Method for Determining Battery State of Charge by Measuring A.C. Electrical Phase Angle Change.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE ARMY WASHINGTON D C

Personal Author(s) : Dowgiallo,Edward J , Jr

Report Date : 05 Oct 1976

Pagination or Media Count : 7

Abstract : Several embodiments for determining the state of charge of a cell or battery are disclosed. In accordance with one method of this invention, an A.C. voltage is applied to a cell or battery through a shunt. The phase angle between the A.C. voltage across the battery terminals and the A.C. current through the battery (measured as a shunt voltage) is continuously monitored. This phase angle is converted to an analog voltage which represents the A.C. component that is phase shifted by the impedance of the battery.

Descriptors :   *Patents, *Electric batteries, *Phase measurement, Battery chargers, Voltage

Subject Categories : Electrochemical Energy Storage

Distribution Statement : APPROVED FOR PUBLIC RELEASE