APPARATUS AND METHOD FOR STATE OF CHARGE (SOC) DETERMINATION FOR BATTERY

• US 20170045587A1
• Filed: 08/15/2016
• Published: 02/16/2017
• Est. Priority Date: 08/13/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: YEO, Tae Jung, KIM, Jin Ho, SONG, Tae Won
• Granted Patent: US 10,627,452 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/3828 using current integration
• CPC Class Codes: G01R 31/387 Determining ampere-hour charge capacity or SoC
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature

Abstract

Battery state of charge (SOC) determination apparatuses and methods are disclosed, where the battery SOC determination apparatus includes a grouper configured to cluster the cells in the battery pack into the groups based on similarity of the sensing data among the cells, a representative cell selector configured to select the representative cell for the each group, a first SOC estimator configured to estimate the SOC of the representative cell of the each group based on the battery model, and a second SOC estimator configured to determine the SOC of the battery pack based on the SOC of the representative cell of the each group.

Claims

1. An apparatus for battery state of charge (SOC) determination, the apparatus comprising:

a processor configured to;

cluster cells in a battery pack into groups based on similarity of sensing data among the cells;

select a representative cell for each group;

estimate a SOC of the representative cell of each group based on a battery model; and

determine a SOC of the battery pack based on the SOC of the representative cell of the each group.

2. The apparatus of claim 1, wherein the processor comprises:

a grouper configured to cluster the cells in the battery pack into the groups based on similarity of the sensing data among the cells;

a representative cell selector configured to select the representative cell for the each group;

a first SOC estimator configured to estimate the SOC of the representative cell of the each group based on the battery model; and

a second SOC estimator configured to determine the SOC of the battery pack based on the SOC of the representative cell of the each group.

3. The apparatus of claim 2, wherein the sensing data of each of the cells comprises any one or any combination of a current, a voltage, and a temperature of the each cell.

4. The apparatus of claim 2, wherein the grouper is further configured to cluster the cells into the groups at designated group update intervals.

5. The apparatus of claim 2, wherein the representative cell selector is further configured to select the representative cell of the each group at designated representative cell update intervals.

6. The apparatus of claim 5, wherein the representative cell selector is further configured to either number the cells in a group and to select each of the numbered cells in turn as the representative cell at the representative cell update intervals, or to randomly select a cell from the each group as the representative cell at the representative cell update intervals.

7. The apparatus of claim 2, wherein the battery model comprises either an electric circuit model or an electro-chemical model.

8. The apparatus of claim 2, wherein the second SOC estimator is further configured to estimate a SOC of each cell in the each group based on the estimated SOC of the representative cell of the each group, and to estimate the SOC of the battery pack based on the SOC of each of the cells and the SOC of the each of the representative cells.

9. The apparatus of claim 8, wherein the second SOC estimator is further configured to estimate the SOC of the each cell in the each group by applying a variance of the SOC of the representative cell of the each group to an initial SOC value of the each cell.

10. The apparatus of claim 8, wherein the second SOC estimator is further configured to estimates the SOC of the battery pack using measures of central tendency of the SOC of the each cell.

11. The apparatus of claim 2, further comprising:

an eccentric cell detector configured to detect an eccentric cell from the cells based on a result of cell clustering.

12. The apparatus of claim 11, wherein the eccentric cell detector is further configured to detect, as the eccentric cell, a cell that has not been classified into the groups, or has continuously changed its group according to the group update intervals.

13. The apparatus of claim 2, further comprising:

a calibrator configured to calibrate the SOC of the representative cell of the each group.

14. A method for battery state of charge (SOC) determination, the method comprising:

clustering cells in a battery pack into groups based on similarity of sensing data among the cells;

selecting a representative cell of each group;

estimating a SOC of the representative cell of each group based on a battery model; and

determining a SOC of the battery pack based on the SOC of the representative cell of the each group.

15. The method of claim 14, wherein the sensing data of each of the cells comprises any one or any combination of a current, a voltage, and a temperature of the each cell.

16. The method of claim 14, wherein the clustering of the cells is performed at designated group update intervals.

17. The method of claim 14, wherein the selecting of the representative cell of the each group is performed at designated representative cell update intervals.

18. The method of claim 17, wherein the selecting of the representative cell of each group comprises numbering the cells in a group and selecting each of the numbered cells in turn as the representative cell at the representative cell update intervals, or randomly selecting a cell from the each group as the representative cell at the representative cell update intervals.

19. The method of claim 14, wherein the battery model comprises either an electric circuit model or an electro-chemical model.

20. The method of claim 14, wherein the determining of the SOC of the battery pack comprises estimating a SOC of each cell in the each group based on the estimated SOC of the representative cell of the each group, and determining the SOC of the battery pack based on the SOC of the cells and the SOC of the each of the representative cells.

21. The method of claim 20, wherein the determining of the SOC of the each cell in the each group comprises estimating the SOC of the each cell by applying a variance of the SOC of the representative cell of the each group to an initial SOC value of each of the each cell.

22. A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform the method of claim 14.