Granted Patent B2

US 12,656,407 · App. 17/924,282 · Granted Jun 16, 2026

Inventors: Hyun-Jun Choi (Daejeon, KR); Dae-Soo Kim (Daejeon, KR); Young-Deok Kim (Daejeon, KR); Bo-Mi Lim (Daejeon, KR)

Assignee: LG Energy Solution, Ltd.

G01R31/392G01R31/367G01R31/388

Abstract

Claims (48)

1 . An apparatus for diagnosing a state of a battery, the apparatus comprising:

a controller; and

memory having programmed thereon instructions that, when executed by the controller, cause the controller to:

receive a voltage profile of the battery for a voltage and a capacity of the battery;

obtain a differential profile for the voltage and a differential capacity from the voltage profile;

select a plurality of peaks included in a predetermined voltage section from the differential profile, wherein the predetermined voltage section corresponds to a voltage range within which a first reference peak and a second reference peak of a preset reference profile appear;

determine a first peak associated with a negative electrode and a second peak associated with a positive electrode from among the plurality of peaks;

compare the first peak and the second peak with the first reference peak and the second reference peak of the preset reference profile, respectively; and

diagnose the state of the battery based on at least one of a difference between the first peak and the first reference peak or a difference between the second peak and the second reference peak.

2 . The apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to set a largest peak in the preset reference profile as the first reference peak, and set a second largest peak in the preset reference profile as the second reference peak.

3 . The apparatus according to claim 2 ,

wherein each peak of the plurality of peaks in the differential profile, the first reference peak, and the second reference peak in the preset reference profile is a point at which a slope is 0, and at which an instantaneous change rate according to the voltage switches from positive to negative.

4 . The apparatus according to claim 2 ,

wherein the instructions are configured to cause the controller to set one of the plurality of peaks corresponding to the first reference peak in the differential profile as the first peak, and set another one of the plurality of peaks corresponding to the second reference peak in the differential profile as the second peak.

5 . The apparatus according to claim 1 ,

wherein the preset reference profile is a first profile for the voltage and the differential capacity of a reference cell corresponding to the battery, wherein the voltage and the differential capacity are measured while the reference cell is being charged within a predetermined C-rate range.

6 . The apparatus according to claim 5 ,

wherein the differential profile is a second profile for the voltage and the differential capacity of the battery, wherein the voltage and the differential capacity of the second profile are measured while the battery is being charged within the predetermined C-rate range.

7 . The apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to:

calculate a second peak change value by comparing the second peak with the second reference peak; and

diagnose whether the battery is degraded based on the second peak change value.

8 . The apparatus according to claim 7 ,

wherein the instructions are configured to cause the controller to:

in response to the diagnosis indicating that the battery is degraded, calculate a first peak change value by comparing the first peak with the first reference peak; and

diagnose a cause of the degradation of the battery based on the first peak change value and the second peak change value.

9 . The apparatus according to claim 8 ,

wherein the instructions are configured to cause the controller to, in response to the first peak change value and the second peak change value being equal to or greater than a predetermined magnitude, diagnose that the cause of the degradation of the battery is negative electrode degradation and positive electrode degradation.

10 . The apparatus according to claim 8 ,

wherein the instructions are configured to cause the controller to, in response to the first peak change value being smaller than a predetermined magnitude and the second peak change value being equal to or greater than the predetermined magnitude, diagnose that the cause of the degradation of the battery is positive electrode degradation.

11 . The apparatus according to claim 7 ,

wherein the instructions are configured to cause the controller to, in response to the diagnosis indicating that the battery is degraded, adjust at least one of an upper limit of a state of charge (SOC) of the battery, a lower limit of the SOC of the battery, or an upper limit of a charging/discharging C-rate of the battery.

12 . The apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to:

at each of a plurality of charging cycles in which the battery is charged, receive a respective voltage profile, wherein the memory is configured to store respective voltage profiles of the plurality of charging cycles;

for each respective voltage profile obtain a respective differential profile from the respective voltage profile;

for each respective differential profile, determine a respective first peak and a respective second peak in the respective differential profile; and

diagnose whether the battery is degraded based on at least one of a difference between the respective first peak and the first reference peak, or a difference between the respective second peak and the second reference peak for at least one of the respective differential profiles of the plurality of charging cycles.

13 . A battery pack comprising the apparatus according to claim 1 .

14 . A vehicle comprising the apparatus according to claim 1 .

15 . A method for diagnosing a state of a battery, the method comprising:

receiving, by a controller, a voltage profile of the battery for voltage and capacity of the battery;

obtaining, by the controller, a differential profile for the voltage and a differential capacity from the voltage profile;

selecting, by the controller, a plurality of peaks included in a predetermined voltage section from the differential profile, wherein the predetermined voltage section corresponds to a voltage range within which a first reference peak and a second reference peak of a preset reference profile appear;

determining, by the controller, a first peak associated with a negative electrode and a second peak associated with a positive electrode from among the plurality of peaks;

comparing, by the controller, the first peak and the second peak with the first reference peak and the second reference peak of the preset reference profile, respectively; and

diagnosing, by the controller, the state of the battery based on at least one of a difference between the first peak and the first reference peak or a difference between the second peak and the second reference peak.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (32)