METHOD AND SYSTEM FOR MAGNETIC FIELD PROBING FOR SEALED-ACID BATTERY DIAGNOSIS

• US 20130088204A1
• Filed: 10/08/2012
• Published: 04/11/2013
• Est. Priority Date: 10/10/2011
• Status: Active Grant

• Current Assignee: Villanova University
• Original Assignee: Villanova University
• Inventors: Singh, Pritpal, Vassiliou, John, Khare, Neeta
• Granted Patent: US 9,184,611 B2
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/005 Detection of state of health [SOH]

Abstract

A system and method for determining the health of a battery. A primary coil may be positioned along a first portion of a battery and a secondary coil may be positioned along a second portion of the battery. The primary coil may then be excited with a signal, and an electromagnetic field induced in the secondary coil by the excited primary coil may be measured. A state of health of the battery may thus correlate to the measured electromagnetic field during operation of the battery. This state of health may be determined as a function of electrolyte stratification, current profile, electrode structure, electrode surface degradation, and combinations thereof.

Claims

1. A method comprising the steps of:

positioning a primary coil along a first portion of a battery;

positioning a secondary coil along a second portion of the battery;

exciting the primary coil with a signal; and

measuring an electromagnetic field induced in the secondary coil by the excited primary coil,

wherein the measured electromagnetic field correlates to a state of health of the battery during operation thereof.

2. The method of claim 1 wherein the second portion of the battery opposes the first portion of the battery and wherein the induced electromagnetic field is substantially perpendicular to an electric field between electrodes in the battery.

3. The method of claim 1 wherein the battery is a lead acid battery, a lithium-ion battery, or a sealed lead acid battery.

4. The method of claim 1 wherein the battery is part of an electric vehicle, a hybrid electric vehicle, an uninterrupted power supply system, a backup power system for a cell tower, a power system for a cell tower, a backup power system for a data storage system, a grid energy storage system, or a power system for a data storage system.

5. The method of claim 1 wherein the operation comprises a discharging, charging, or equilibrium process.

6. The method of claim 1 wherein the signal is a sinusoidal signal.

7. The method of claim 1 wherein the state of health is determined as a function of a value selected from the group consisting of electrolyte stratification, current profile, electrode structure, capacity loss, increase in impedance, change in temperature, electrode leakage, electrode material loss, polymer aging, electrode surface degradation, and combinations thereof.

8. The method of claim 1 wherein the electromagnetic field is an alternating current electromagnetic field.

9. The method of claim 1 further comprising the step of determining a state of health of the battery during operation of the battery using the measured electromagnetic field.

10. The method of claim 9 wherein the step of determining a state of health of the battery further comprises inferring electrolyte stratification, current profile, electrode structure, capacity loss, increase in impedance, change in temperature, electrode leakage, electrode material loss, polymer aging, or electrode surface degradation from additional primary and secondary coils positioned at different portions of the battery.

11. A system for monitoring a battery comprising:

a primary coil positioned along a first portion of a battery;

a secondary coil positioned along a second portion of the battery;

a signal generator connected to the primary coil for generating a signal to excite the primary coil; and

a signal analyzer for measuring a magnetic response induced in the secondary coil by the excited primary coil,

wherein the measured magnetic response correlates to battery health.

12. The system of claim 11 wherein the second portion of the battery opposes the first portion of the battery and wherein the induced magnetic response is substantially perpendicular to an electric field between electrodes in the battery.

13. The system of claim 11 wherein the battery is a lead acid battery, a lithium-ion battery, or a sealed lead acid battery.

14. The system of claim 11 wherein the signal analyzer is a voltmeter or a spectrum analyzer.

15. The system of claim 11 wherein the battery is part of an electric vehicle, a hybrid electric vehicle, an uninterrupted power supply system, a backup power system for a cell tower, a power system for a cell tower, a backup power system for a data storage system, a grid energy storage system, or a power system for a data storage system.

16. The system of claim 11 wherein the generated signal is a sinusoidal signal.

17. The system of claim 11 further comprising additional primary and secondary coils positioned at different portions of the battery to monitor battery health at different levels of the battery.

18. The system of claim 11 wherein battery health is determined as a function of a value selected from the group consisting of electrolyte stratification, current profile, electrode structure, capacity loss, increase in impedance, change in temperature, electrode leakage, electrode material loss, polymer aging, electrode surface degradation, and combinations thereof.

19. The system of claim 11 further comprising a wireless or wire-line transmitter to provide information from the signal analyzer to a processor remote from the battery.

20. A non-invasive magnetic field probing method to monitor a battery during battery operation comprising the steps of:

generating an alternating current magnetic field between at least one pair of coils situated on a battery;

measuring changes in the magnetic field across the battery; and

determining a state of health of the operating battery as a function of the measured magnetic field changes.

21. The method of claim 20 wherein the step of determining a state of health further comprises inferring electrolyte stratification, current profile, electrode structure, capacity loss, increase in impedance, change in temperature, electrode leakage, electrode material loss, polymer aging, or electrode surface degradation from the measured magnetic field changes.

22. The method of claim 20 wherein the battery is a lead acid battery, a lithium-ion battery, or a sealed lead acid battery.