US-12625187-B2 - Method and apparatus with battery state estimation

Abstract

A processor-implemented method with battery state estimation includes: determining a state variation of a battery using a voltage difference between a sensed voltage of the battery and an estimated voltage of the battery that is estimated by an electrochemical model corresponding to the battery; updating an internal state of the electrochemical model based on the determined state variation of the battery; and estimating state information of the battery based on the updated internal state of the electrochemical model.

Inventors

• Jinho Kim
• Tae Won Song

Assignees

• SAMSUNG ELECTRONICS CO., LTD.
• SAMSUNG SDI CO., LTD.

Dates

Publication Date

20260512

Application Date

20240410

Priority Date

20191022

Claims (5)

1. 1 . An apparatus with battery state estimation, comprising: a processor configured to: obtain a sensed voltage of a battery from a voltage sensor; estimate, using an electrochemical model, an estimated voltage of the battery from the sensed voltage; determine a first voltage difference between the sensed voltage of the battery and the estimated voltage of the battery; in response to the first voltage difference being greater than a threshold voltage difference, determine a correction method of correcting an internal state of the electrochemical model; in response to the first voltage difference being less than or equal to the threshold voltage difference, determine a correction method of correcting a sensed current to be input to the electrochemical model, to apply the determined correction method to the electrochemical model; estimate state information of the battery using the electrochemical model to which the determined correction method is applied; and perform at least one of operations including monitoring abnormalities, preventing over-charge, preventing over-discharge, performing thermal control, or performing cell balancing based on a result of the estimating state information of the battery.
2. 2 . The apparatus of claim 1 , wherein the processor is further configured to update the internal state of the electrochemical model using a state variation of the battery determined by the first voltage difference between a voltage of the battery sensed in a current time period and a voltage of the battery estimated by the electrochemical model; or correct a sensed current of the battery in the current time period to be input to the electrochemical model using a capacity error corresponding to a second voltage difference between a sensed voltage of the battery in a previous time period and an estimated voltage of the battery in the previous time period.
3. 3 . The apparatus of claim 1 , wherein the processor is further configured to determine a correction method of the electrochemical model such that the correction method of correcting the sensed current to be input to the electrochemical model is to be performed more frequently than the correction method of correcting the internal state of the electrochemical model.
4. 4 . An apparatus with battery state estimation, comprising: a processor configured to: obtain a sensed voltage of a battery from a voltage sensor; estimate, using an electrochemical model, an estimated voltage of the battery from the sensed voltage; determine a first voltage difference between the sensed voltage of the battery and the estimated voltage of the battery; determine one of a plurality of correction methods of the electrochemical model based on a result of comparing the first voltage difference to a threshold voltage difference; depending on the determined correction method, correct an internal state of the electrochemical model or correcting a sensed current to be input to the electrochemical model, by applying the determined correction method to the electrochemical model; estimate state information of the battery using the electrochemical model to which the determined correction method is applied; and perform at least one of operations including monitoring abnormalities, preventing over-charge, preventing over-discharge, performing thermal control, or performing cell balancing based on a result of the estimating state information of the battery, wherein the processor is further configured to determine the correction method of the electrochemical model such that a correction method of correcting the sensed current to be input to the electrochemical model is to be performed more frequently than a correction method of correcting the internal state of the electrochemical model.
5. 5 . The apparatus of claim 4 , wherein the determining of the correction method of the electrochemical model based on the first voltage difference comprises: in response to the first voltage difference being greater than the threshold voltage difference, selecting the correction method of correcting the internal state of the electrochemical model; and in response to the first voltage difference being less than or equal to the threshold voltage difference, selecting the correction method of correcting the sensed current to be input to the electrochemical model.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of application Ser. No. 17/683,483 filed on Mar. 1, 2022, which is a division of application Ser. No. 16/814,212 filed on Mar. 10, 2020, which claims the benefit under 35 USC § 119(a) of Korean Patent Application No. 10-2019-0131570 filed on Oct. 22, 2019, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. BACKGROUND 1. Field The following description relates to a method and apparatus with battery state estimation. 2. Description of Related Art There are various methods to estimate a state of a battery. For example, such methods may include estimating a state of a battery by integrating an electrical current of a battery or using a battery model, for example, an electric circuit model or an electrochemical model. SUMMARY This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. In one general aspect, a processor-implemented method with battery state estimation includes: determining a state variation of a battery using a voltage difference between a sensed voltage of the battery and an estimated voltage of the battery that is estimated by an electrochemical model corresponding to the battery; updating an internal state of the electrochemical model based on the determined state variation of the battery; and estimating state information of the battery based on the updated internal state of the electrochemical model. The determining of the state variation of the battery may include determining the state variation of the battery based on the voltage difference, previous state information previously estimated by the electrochemical model, and an open-circuit voltage (OCV) table. The determining of the state variation of the battery may further include obtaining an OCV corresponding to the previous state information based on the OCV table, and applying the voltage difference to the obtained OCV. The updating of the internal state of the electrochemical model may include correcting an ion concentration distribution in an active material particle or an ion concentration distribution in an electrode based on the determined state variation of the battery. The updating of the internal state of the electrochemical model may include uniformly correcting an ion concentration distribution in an active material particle or an ion concentration distribution in an electrode based on the determined state variation of the battery. The updating of the internal state of the electrochemical model may include determining a concentration gradient characteristic based on a diffusion characteristic based on the determined state variation of the battery, and correcting an ion concentration distribution of the battery based on the determined concentration gradient characteristic. The updating of the internal state of the electrochemical model may further include calculating a diffusion equation of an active material based on the determined state variation of the battery, and correcting an ion concentration distribution in an active material particle or an ion concentration distribution in the electrode. The internal state of the electrochemical model may include any one or any combination of any two or more of a positive electrode lithium-ion concentration distribution of the battery, a negative electrode lithium-ion concentration distribution of the battery, and an electrolyte lithium-ion concentration distribution of the battery. The method may further include: verifying whether the voltage difference between the sensed voltage of the battery and the estimated voltage of the battery exceeds a threshold voltage difference. The electrochemical model may be configured to estimate state information of a target battery among a plurality of batteries. The sensed voltage may be a voltage measured from the target battery. The estimated voltage may be a voltage previously estimated from another battery among the plurality of batteries by the electrochemical model. The battery may be a battery cell, a battery module, or a battery pack. The estimated state information of the battery may include any one or any combination of any two or more of a state of charge (SOC), a state of heath (SOH), and abnormality state information. In another general aspect, a non-transitory computer-readable storage medium stores instructions that, when executed by a processor, cause the processor to perform the method described above. In another general aspect, a processor-implemented method with battery state estimation includes: obtaining sensing data including a sensed voltage of a battery; obtaining an estimated voltage of the b