REAL-TIME ESTIMATION OF CELL CORE TEMPERATURE DURING PERIOD OF REST

• US 20120128026A1
• Filed: 05/20/2011
• Published: 05/24/2012
• Est. Priority Date: 05/25/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Kenkre, Mahendra M., Liu, Wei, Leutheuser, Andrew H., Hua, Charles
• Granted Patent: US 8,936,394 B2
• Time in Patent Office: Days
• US Class Current: 374/134
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Methods and systems for estimating the core temperature of at least one cell in a battery at the termination of a rest period. The method for estimating the core temperature of the cells in a battery includes measuring the surface temperature of the cells, obtaining the estimated core temperature of the cells, obtaining the time required for the surface temperature and the estimated core temperature of the cells to converge, and estimating the core temperature of the cells based on the measured surface temperatures, the obtained estimated core temperature, and the obtained time. The system for estimating the core temperature of the cells in a battery includes at least one sensor configured to receive temperature information and a control system in signal communication with the sensor, wherein the control system comprises a memory device and a controller.

Claims

1. A method for estimating the core temperature of at least one cell in a battery at the termination of a rest period, the method comprising:

measuring the surface temperature of the at least one cell at the initiation of the rest period and at the termination of the rest period;

obtaining the estimated core temperature of the at least one cell at the initiation of the rest period;

obtaining the time required for the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period to converge; and

estimating the core temperature of the at least one cell at termination of the rest period based on the measured surface temperatures, the obtained estimated core temperature, and the obtained time.

2. The method of claim 1, wherein the initiation of the rest period comprises key-off.

3. The method of claim 1, wherein the termination of the rest period comprises key-on.

4. The method of claim 1, wherein said method comprises estimating the core temperature of a plurality of cells, wherein obtaining the time required for the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period to converge comprises:

measuring the time required for the surface temperature of the at least one cell and the estimated core temperature of the at least one cell to converge; and

applying the measured time required for the surface temperature of the at least one cell and the estimated core temperature of the at least one cell to converge to a plurality of cells which are similarly situated to the at least one cell, such that the core temperature of a plurality of cells may be estimated.

5. The method of claim 1, further comprising measuring the time from the initiation of the rest period to the termination of the rest period and applying it to the method such that the estimated core temperature of the at least one cell at the termination of the rest period is additionally based on the measured time.

6. The method of claim 5, wherein the measured time is less than the obtained time.

7. The method of claim 6, wherein the estimated core temperature of the at least one cell at the termination of the rest period is characterized by the following relationship:

8. The method of claim 1, wherein the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period converge at the ambient temperature.

9. The method of claim 1, wherein the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period decrease or increase from the initiation of the rest period to the termination of the rest period.

10. The method of claim 1, wherein the surface temperature of the at least one cell at the initiation of the rest period is greater than the estimated core temperature of the at least one cell at the initiation of the rest period.

11. The method of claim 1, wherein the surface temperature of the at least one cell at the initiation of the rest period is less than the estimated core temperature of the at least one cell at the initiation of the rest period.

12. The method of claim 1, wherein the surface temperatures are measured with a sensor.

13. A method for estimating the core temperature of at least one cell in a battery at the termination of a rest period in real-time, the method comprising:

measuring the surface temperature of the at least one cell at the initiation of the rest period and at the termination of the rest period;

obtaining the estimated core temperature of the at least one cell at the initiation of the rest period;

obtaining the time required for the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period to converge;

measuring the time from the initiation of the rest period to the termination of the rest period; and

estimating the core temperature of the at least one cell at the termination of the rest period based on the measured surface temperatures, the obtained estimated core temperature, the obtained time, and the measured time.

14. The method of claim 13, wherein the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period converge at the ambient temperature.

15. The method of claim 14, wherein the surface temperature of the at least one cell at the initiation of the rest period is less than the estimated core temperature of the at least one cell at the initiation of the rest period and wherein the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period decrease from the initiation of the rest period to the termination of the rest period.

16. A system for estimating the core temperature of at least one cell in a battery in a vehicle at the termination of a rest period, wherein the vehicle receives at least a portion of its power from the battery, the system comprising:

at least one sensor configured to receive temperature information from the battery; and

a control system in signal communication with the sensor, wherein the control system comprises a memory device and a controller in signal communication with the memory device with instructions for estimating the core temperature of at least one cell in the battery at the termination of the rest period, the instructions being written to;

measure the surface temperature of the at least one cell at the initiation of the rest period and at the termination of the rest period;

obtain the estimated core temperature of the at least one cell at the initiation of the rest period;

obtain the time required for the surface temperature of the at least one cell at the initiation of the rest period and the estimated core temperature of the at least one cell at the initiation of the rest period to converge; and

estimate the core temperature of the at least one cell at termination of the rest period based on the measured surface temperatures, the obtained estimated core temperature, and the obtained time.

17. The system of claim 16, wherein initiation of the rest period comprises key-off and wherein the termination of the rest period comprises key-on.

18. The system of claim 16, further comprising a timing device in signal communication with the controller.

19. The system of claim 18, wherein the instructions are further written to measure the time from the initiation of the rest period to the termination of the rest period, such that the estimated core temperature of the at least one cell at the termination of the rest period is based on the measured surface temperatures, the obtained estimated core temperature, the obtained time, and the measured time.

20. The system of claim 19, wherein the measured time is less than the obtained time.

21. The system of claim 16, wherein the estimated core temperature of the at least one cell at the termination of the rest period is characterized by the following relationship:

22. A vehicle incorporating the system of claim 16.