DEVICE AND METHOD FOR ESTIMATING SECONDARY CELL STATUS

• US 20150046108A1
• Filed: 09/18/2012
• Published: 02/12/2015
• Est. Priority Date: 03/13/2012
• Status: Active Grant

• Current Assignee: Primearth EV Energy Company Limited (Toyota Motor Corporation)
• Original Assignee: Primearth EV Energy Company Limited (Toyota Motor Corporation)
• Inventors: Akamine, Naoshi
• Granted Patent: US 10,120,032 B2
• Time in Patent Office: Days
• US Class Current: 702/63
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• 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 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/48 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 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Provided is a device for estimating secondary cell status using multiple models. The device for estimating secondary cell status uses multiple models, model 1, model 2, and model 3, to estimate the status of respective secondary cells. An arithmetic unit compares the estimated voltage values obtained from model 1, model 2, and model 3 with measured voltage values, sets the model having the highest correlation as the optimal model, optimizes the parameters of such model, and estimates secondary cell status.

Claims

1. A device for estimating a secondary cell status comprising:

voltage detection means for detecting a voltage of the secondary cell; and

computation means for estimating the secondary cell status by use of a plurality of models, the means including comparing estimated voltage values acquired from the plurality of models with a voltage value detected by the voltage detection means, selecting a model exhibiting highest correlation between the estimated voltage value and the voltage value as an optimum model, and estimating the secondary cell status by optimizing a parameter used in the optimum model by use of the voltage value detected by the voltage detection means.

10. The device for estimating a secondary cell status according to claim 1, wherein the parameter is optimized by means of any two or more selected from among the voltage value detected by the voltage detection means, a current value detected by current detection means, and a temperature detected by temperature detection means.

2. A device for estimating a secondary cell status comprising:

voltage detection means for detecting a voltage of the secondary cell; and

computation means for estimating the secondary cell status by use of a plurality of models, the means including comparing estimated voltage values acquired from the plurality of models with a voltage value detected by the voltage detection means at every predetermined period, selecting, as an optimum model, a model exhibiting highest correlation between the estimated voltage value and the voltage value, and estimating the secondary cell status by use of the selected optimum model.

3. The device for estimating a secondary cell status according to claim 2, wherein the computation means optimizes a parameter used in the optimum model by use of the voltage value detected by the voltage detection means, thus estimating the secondary cell status.

4. (canceled)

5. A device for estimating a secondary cell status comprising:

voltage detection means for detecting a voltage of the secondary cell; and

computation means for estimating the secondary cell status by use of a plurality of models, the means including optimizing parameters used respectively in the plurality of models by use of the voltage value detected by the voltage detection means, selecting, as an optimum model, a model involving least change in an amount of parameter correction from among the plurality of models having the optimized parameters, and estimating the secondary cell status by use of the selected optimum model.

6. The device for estimating a secondary cell status according to claim 5, wherein the computation means optimizes the parameters used respectively in the plurality of models at every predetermined period and selects, as an optimum model, the model involving the least change in the amount of parameter correction acquired from the plurality of models having the optimized parameters.

12. The device for estimating a secondary cell status according to claim 5, wherein the parameter is optimized by means of any two or more selected from among the voltage value detected by the voltage detection means, a current value detected by current detection means, and a temperature detected by temperature detection means.

7. A device for estimating a secondary cell status comprising:

voltage detection means for detecting a voltage of the secondary cell; and

computation means for estimating the secondary cell status by use of a plurality of models by switching between first processing and second processing in which the first processing includes comparing estimated voltage values acquired from the plurality of models with a voltage value detected by the voltage detection means, selecting as an optimum model a model exhibiting the highest correlation between the estimated voltage value and the voltage value, and optimizing a parameter used in the optimum model by use of the voltage value detected by the voltage detection means and in which the second processing includes optimizing parameters used respectively in the plurality of models by use of the voltage value detected by the voltage detection means and selecting as an optimum model a model exhibiting least change in an amount of change in parameter correction acquired in the plurality of models having the optimized parameters, thus estimating the secondary cell status.

8. The device for estimating a secondary cell status according to claim 7, wherein the computation means estimates the secondary cell status by the first processing at every first period and estimates the secondary cell status by the second processing at every second period that is relatively longer than the first period.

9. The device for estimating a secondary cell status according to claim 7, wherein the computation means estimates the secondary cell status by the second processing when the secondary cell is in an excessively charged region or an excessively discharged region and estimates the secondary cell status by the first processing when the secondary cell is in neither the excessively charged region nor the excessively discharged region.

13. The device for estimating a secondary cell status according to claim 7, wherein the parameter is optimized by means of any two or more selected from among the voltage value detected by the voltage detection means, a current value detected by current detection means, and a temperature detected by temperature detection means.

11. (canceled)