Accession Number : ADD004176

Title :   Battery Thermal Runaway Monitor.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Benham,Harold L ; Clark,Steven D ; Huffman,Herbert L ; Stovall,Ronald J

Report Date : 15 Jun 1977

Pagination or Media Count : 21

Abstract : A device for determining a thermal runaway condition in a nickel-cadmium battery is described. A current sensor develops a DC voltage proportional to battery current and a converter converts the voltage to a pulse train whose frequency is directly proportional to battery current. The pulse train frequency is monitored for fixed periods of times and changes of frequencies are used to determine the slope of the charge current. A maximum allowable slope is specified and fed into a binary up/down counter which also counts the pulse train frequency. When the difference between two pulse train frequency readings is greater than the maximum allowable, a possible thermal runaway condition is indicated and after a predetermined number of consecutive indications, an indicator is energized to provide a warning. (Author)

Descriptors :   *Nickel cadmium batteries, *Monitors, *Patent applications, Monitoring, Electric current, Voltage, Pulse trains, Battery chargers, Heating

Subject Categories : Electrochemical Energy Storage

Distribution Statement : APPROVED FOR PUBLIC RELEASE