Battery management apparatus and method

Patent metadata

Field	Value
Publication number	US-12405310-B2
Application number	US-202117923027-A
Country	US
Kind code	B2
Filing date	Nov 17, 2021
Priority date	Nov 17, 2020
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

A battery management apparatus and method capable of preventing lithium plating from occurring in a battery cell by determining an optimal upper limit C-rate corresponding to the battery cell. In particular, since the charging and discharging of the battery cell may be controlled according to the determined upper limit C-rate, it is possible to prevent side reactions from occurring in the battery cell due to charging and discharging according to the high C-rate, and since the degradation of the battery cell may be slowed, the lifespan of the battery cell may be increased.

First claim

What is claimed is:

1. A battery management apparatus, which manages a battery cell charged multiple times at each of a plurality of current rates (C-rates), comprising:
a controller; and
memory having stored thereon instructions that, when executed, are configured to cause the controller to:
for each of a plurality of battery profiles representing a relationship between voltage and capacity of a battery cell at respective current rates (C-rates), obtain a differential profile representing a relationship between the voltage and a differential capacity of the battery cell;
classify the plurality of differential profiles into a threshold differential profile corresponding to a preset threshold C-rate and a plurality of reference differential profiles;
determine a threshold peak in the threshold differential profile;
determine a plurality of reference peaks including a respective reference peak in each of the plurality of reference differential profiles;
compare a voltage of the determined threshold peak with a voltage of the plurality of determined reference peaks; and
determine an upper limit C-rate for the battery cell based on the comparison, wherein the battery cell is configured to be charged and/or discharged at a C-rate equal to or less than the upper limit C-rate.

2. The battery management apparatus according to claim 1 ,
wherein the instructions are configured to cause the controller to:
for each respective reference peak of the plurality of reference peaks, calculate a respective voltage difference between the threshold peak and the reference peak;
compare the respective calculated voltage differences with a preset threshold voltage; and
determine the upper limit C-rate based on the comparison.

3. The battery management apparatus according to claim 2 ,
wherein the instructions are configured to cause the controller to:
determine a reference peak for which the corresponding calculated voltage difference is equal to or greater than the threshold voltage as a target peak; and
determine a C-rate corresponding the reference differential profile including the determined target peak as the upper limit C-rate.

4. The battery management apparatus according to claim 2 ,
wherein the instructions are configured to cause the controller to:
generate a voltage profile representing a relationship between the respective voltage differences and the plurality of C-rates; and
determine an upper limit C-rate as the threshold voltage in the generated voltage profile.

5. The battery management apparatus according to claim 2 ,
wherein the instructions are configured to cause the controller to:
obtain the plurality of battery profiles;
determine, from among the plurality of obtained battery profiles, a threshold battery profile corresponding to the threshold C-rate and a reference battery profile corresponding to a reference C-rate; and
set the threshold voltage based on the determined threshold battery profile and the determined reference battery profile.

6. The battery management apparatus according to claim 5 ,
wherein the instructions are configured to cause the controller to:
select a reference capacity satisfying a predetermined condition in the reference battery profile; and
set a voltage corresponding to the reference capacity in the threshold battery profile as the threshold voltage.

7. The battery management apparatus according to claim 6 ,
wherein the instructions are configured to cause the controller to select a capacity corresponding to a point in the reference battery profile at which a negative electrode voltage is 0 as the reference capacity.

8. The battery management apparatus according to claim 6 ,
wherein the instructions are configured to cause the controller to set a negative electrode voltage corresponding to the reference capacity in the threshold battery profile as the threshold voltage.

9. A battery pack, comprising the battery management apparatus according to claim 1 .

10. A battery management method, which manages a battery cell charged multiple times at each of a plurality of C-rates, comprising:
obtaining a plurality of battery profiles representing a corresponding relationship between voltage and capacity of the battery cell at each of the plurality of C-rates;
for each of a plurality of battery profiles representing a relationship between voltage and capacity of a battery cell at respective C-rate, obtaining, by a controller, a differential profile representing a relationship between the voltage and a differential capacity of the battery cell;
classifying, by the controller, the plurality of differential profiles into a threshold differential profile corresponding to a preset threshold C-rate and a plurality of reference differential profiles;
determining, by the controller, a threshold peak in the threshold differential profile;
determining, by the controller, a plurality of reference peaks including a respective reference peak in each of the plurality of reference differential profiles;
comparing, by the controller, a voltage of the determined threshold peak with a voltage of the plurality of determined reference peaks; and
determining, by the controller, an upper limit C-rate for the battery cell based on the comparison, wherein the battery cell is configured to be charged and/or discharged at a C-rate equal to or less than the upper limit C-rate.

Assignees

• Lg Energy Solution Ltd

Inventors

• Bae Yoon-Jung
• Cha A-Ming

Classifications

• H02J7/933 Primary

  the cycle being controlled or terminated in response to electric parameters · CPC title

• H01M2010/4271

  Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing · CPC title

• H01M10/46

  Accumulators structurally combined with charging apparatus (circuits for charging H02J7/00) · CPC title

• G01R31/382

  Arrangements for monitoring battery or accumulator variables, e.g. SoC · CPC title

• G01R31/396

  Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery · CPC title