System and method to determine the state of charge of a battery using magnetostriction to detect magnetic response of battery material

• US 8,872,519 B2
• Filed: 08/21/2009
• Issued: 10/28/2014
• Est. Priority Date: 09/26/2008
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Meisner, Gregory P., Verbrugge, Mark W., Herbst, Jan F.
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): PELTON, NATHANIEL R
• Application Number:
  US12/545,311
• Publication Number:
  US 20100079145A1
• Time in Patent Office: 1,894 Days
• Field of Search: 324/432, 324/425, 324/427
• US Class Current: 324/432
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: G01R 1/16 Magnets
• CPC Class Codes: G01R 15/18 using inductive devices, e.g. transformers
• CPC Class Codes: G01R 31/378 specially adapted for the type of battery or accumulator
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4285 Testing apparatus
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

One exemplary embodiment includes a method including providing a battery, producing a first magnetic field so that a second magnetic field is induced in the battery, sensing a magnetic field resulting from the interaction of the first magnetic field and the second magnetic field, utilizing the sensed net magnetic field to determine the state of charge of the battery.

Claims

1. A method comprising:

providing a battery;

producing a first magnetic field of a known constant strength so that a second magnetic field is induced in the battery;

sensing a net magnetic field resulting from the interaction of the first magnetic field and the second magnetic field;

utilizing the sensed net magnetic field to determine or estimate the state of charge of the battery.

2. A method is set forth in claim 1 wherein the sensing a magnetic field comprises providing a magnetic field sensor on a first face of the battery.

3. A method as set forth in claim 2 wherein the producing a first magnetic field comprises providing a magnetic field generating component on a second face of the battery opposite the magnetic field sensor, and causing the magnetic field generating component to produce the first magnetic field.

4. A method as set forth in claim 2 wherein the magnetic field sensor comprises a magnetostriction sensor.

5. A method as set forth in claim 1 further comprising taking action in response to the determined or estimated state of charge of the battery.

6. A method as set forth in claim 5 wherein the taking action comprises recharging the battery.

7. A method as set forth in claim 5 wherein the taking action comprises recharging the battery if the determined or estimated state of charged is less than 15%.

8. A method as set forth in claim 5 wherein the taking action comprises utilizing energy stored in the battery to at least partially power a motor.

9. A method as set forth in claim 1 wherein the producing a first magnetic field comprises providing a permanent magnet on a first face of the battery.

10. A method as set forth in claim 1 wherein the producing a first magnetic field comprises providing a coil wrapped around the battery and flowing current through the coil.

11. A method as set forth in claim 1 wherein the battery comprises a lithium ion battery.

12. A method as set forth in claim 11 wherein the lithium ion battery comprises an electrode comprising iron and phosphate.

13. A method as set forth in claim 1 wherein the battery comprises an electrode having a paramagnetic susceptibility.

14. A method comprising:

providing a battery;

producing a first magnetic field of a known constant strength so that a second magnetic field is induced in the battery;

sensing a net magnetic field resulting from the interaction of the first magnetic field and the second magnetic field;

correlating the sensed net magnetic field to the state of charge of the battery.

15. A product comprising:

a battery;

means for producing a first magnetic field of a known constant strength so that a second magnetic field is induced in the battery;

means for sensing a net magnetic field resulting from the interaction of the first magnetic field and the second magnetic field;

means for determining or estimating the state of charge of the battery by utilizing the sensed net magnetic field.

16. A product as set forth in claim 15 wherein means for sensing a net magnetic field resulting from the interaction of the first magnetic field and the second magnetic field comprises a magnetostriction sensor.

17. A product as set forth in claim 16 wherein the means for producing a first magnetic field of a known strength so that a second magnetic field is induced in the battery comprises a permanent magnet on a first face of the battery.

18. A product as set forth in claim 17 wherein the battery comprises a lithium ion battery.

19. A product as set forth in claim 18 wherein the lithium ion battery comprises an electrode comprising iron and phosphate.

20. A product as set forth in claim 15 wherein the battery comprises an electrode having a paramagnetic susceptibility.