04697134 is referenced by 186 patents and cites 20 patents.

A testing device measures the impedance of secondary cells that form a battery, such as a lead acid battery, while the battery is in a float charge condition and connected to an active electrical load. The impedance measurement is made at a frequency selected to be different from those frequencies otherwise present in the charger-load circuit. A first application of the testing device monitors the battery for a change in impedance that can signal a developing defect in one or more individual cells or intercell connections that can prevent the battery from delivering its stored energy to the load. In a second application, the testing device is used to compare the impedance of individual cells and electrical connections to locate faulty components.

Title
Apparatus and method for measuring battery condition
Application Number
6/892793
Publication Number
4697134
Application Date
July 31, 1986
Publication Date
September 29, 1987
Inventor
Charles M Gabriel
Lombard
IL, US
Merlin E Burkum
Elmhurst
IL, US
Agent
Willian Brinks Olds Hofer Gilson & Lione
Assignee
Commonwealth Edison Company
IL, US
IPC
H02J 7/00
G01N 27/46
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