US 5,705,929 A · Battery capacity monitoring system

Abstract

A method of and apparatus for centrally monitoring the capacity of batteries in a battery string includes electrical leads connected to each battery terminal of the battery string. A capacity testing system a) switches between the electrical leads for sequentially selecting the leads associated with the terminals of each battery, b) measures the internal resistance of the battery associated with each selected pair of electrical leads, c) compares the internal resistance of each battery cell to an internal resistance threshold, and d) triggers an alarm when the internal resistance of a battery exceeds the internal resistance threshold. A central monitoring station monitors battery capacity data and alarm signals from various battery strings, schedules battery capacity testing, transmits control commands to each capacity testing system for i) scheduling testing, ii) initializing upload of capacity data, and iii) requesting status information, provides battery capacity data analysis, and uploads information to a network management computer. The system is especially suitable for centrally monitoring the capacity of batteries located remote from the central station, preferably in external telecommunications housings and telecommunications power rooms.

Claims32

Dependent claims

A system for monitoring the capacity of the batteries in at least one battery string, each battery comprising a pair of terminals, each battery string comprising connecting straps connecting adjacent batteries of the string, the monitoring system comprising:

a plurality of electrical leads, each lead being associated with and electrically connected to a battery terminal of the battery string;
and
capacity testing means associated with each battery string for testing the capacity of each battery in the associated battery string, each capacity testing means comprising:
i) means for switching between the electrical leads for sequentially selecting the pair of electrical leads associated with the terminals of each battery;
ii) means for measuring the internal resistance of the battery associated with each selected pair of electrical leads, said means comprising:
a voltmeter connected between the selected pair of electrical leads for determining the voltage across the terminals of the battery associated with the leads;
a current testing circuit for applying a load resistance across the selected terminals and for measuring the current between the selected terminals under the load resistance;
and
means for calculating the internal resistance of the selected battery from the voltage across the selected terminals and the current between the selected terminals;
iii) means for comparing the internal resistance of each battery cell to an internal resistance threshold;
and
iv) means for triggering an alarm condition when the internal resistance of a battery exceeds the limits of the internal resistance threshold.

9 more elements

A method of monitoring the capacity of the batteries in at least one battery string, each battery comprising a pair of terminals, each battery string comprising connecting straps connecting adjacent batteries of the string, the method comprising the steps of:

a) fixedly attaching electrical leads to the terminals of the batteries in the battery string whereby each battery terminal is in electrical contact with at least one electrical lead;
b) sequentially switching between the electrical leads for selecting the pair of electrical leads associated with the terminals of each battery;
c) measuring the internal resistance of each battery as that battery is selected;
d) comparing the internal resistance of each battery to an internal resistance threshold;
and
e) triggering an alarm condition when the internal resistance of a battery exceeds the internal resistance threshold.

3 more elements

A system for centrally monitoring the capacity of at least one battery in at least one remote location, each battery comprising a pair of terminals, the monitoring system comprising:

a central monitoring station;
and
capacity testing means located at each remote location for testing the capacity of the batteries at that remote location, each capacity testing means comprising:
i) means for switching between electrical leads connected to the battery terminals of the batteries at the remote location for sequentially selecting the pair of electrical leads associated with the terminals of each battery;
ii) means for measuring the internal resistance of the battery associated with each selected pair of electrical leads;
iii) means for comparing the internal resistance of each battery cell to an internal resistance threshold;
iv) means for triggering an alarm condition when the internal resistance of a battery exceeds a limit of the internal resistance threshold;
and
v) means for transmitting the alarm condition to the central station.

6 more elements

Dependencies are inferred from the claim text.

Battery capacity monitoring system

Life of this patent

Battery capacity monitoring system

Life of this patent

Abstract

Claims32