Apparatus and method for diagnosing battery

1 . A battery diagnosing apparatus comprising:

a profile acquisition unit configured to acquire a battery profile representing a correspondence between a voltage and a capacity of a battery; and

a control unit configured to:

divide a capacity section of the battery profile into a plurality of sections,

derive a plurality of target values, wherein each target value of the plurality of target values is related to a differential capacity peak index or a charging capacity ratio index among a plurality of diagnosis indices set in advance and is for a section of the plurality of sections,

compare a correspondence between the plurality of target values with a preset reference profile that represents a correspondence between a plurality of target indices,

diagnose a deterioration state of the battery based on a result of the comparison, and

reduce an upper limit current-rate (C-rate), a constant voltage charging time or an upper charge limit voltage set for the battery based on the deterioration state of the battery,

wherein at least one target value of the plurality of target values is related to a charging capacity ratio index.

2 . The battery diagnosing apparatus according to claim 1 , wherein the control unit is configured to:

determine a number of a plurality of differential capacity peaks included in a differential profile corresponding to the battery profile, the differential profile representing a correspondence between a voltage and a differential capacity, determine the differential capacity peak index as an area of the differential profile, a voltage of a main peak among the plurality of differential capacity peaks, or a differential capacity of the main peak in a corresponding low-capacity section among the plurality of sections, and

determine the charging capacity ratio index in a corresponding high-capacity section among the plurality of sections.

3 . The battery diagnosing apparatus according to claim 1 , wherein the control unit is configured to:

diagnose the deterioration state of the battery as a positive negative electrode deterioration state when a target point indicating the correspondence between the plurality of target values is included in the preset reference profile,

diagnose the deterioration state of the battery as a negative electrode deterioration state when the target point is included in a first region based on the preset reference profile, and

diagnose the deterioration state of the battery as a positive electrode deterioration state when the target point is included in a second region based on the preset reference profile.

4 . The battery diagnosing apparatus according to claim 3 , wherein the control unit is configured to diagnose the deterioration state of the battery as an end of life (EOL) state when the target point is included in a third region, and

the third region is configured to be preset as a region that exceeds a preset threshold value for each of the plurality of target indices.

5 . The battery diagnosing apparatus according to claim 3 , wherein the control unit is configured to reduce the upper limit current-rate (C-rate) or the constant voltage charging time set for the battery when the deterioration state of the battery is diagnosed as the positive electrode deterioration state or the positive negative electrode deterioration state.

6 . The battery diagnosing apparatus according to claim 3 , wherein the control unit is configured to reduce the upper charge limit voltage set for the battery when the deterioration state of the battery is diagnosed as the negative electrode deterioration state or the positive negative electrode deterioration state.

7 . The battery diagnosing apparatus according to claim 1 , wherein the control unit is configured to divide the capacity section into a first section and a second section based on a division ratio or a target capacity set in advance.

8 . The battery diagnosing apparatus according to claim 7 , wherein the profile acquisition unit is configured to further acquire a differential profile corresponding to the battery profile, and

the control unit is configured to determine a main peak from the differential profile and divide the capacity section based on a capacity of the determined main peak.

9 . The battery diagnosing apparatus according to claim 8 , wherein the differential profile is configured to represent a correspondence between a capacity of the battery and a differential voltage, and

the control unit is configured to determine a plurality of local minimum points in the differential profile, and determine a local minimum point with a smallest corresponding differential voltage among the determined plurality of local minimum points, as the main peak.

10 . The battery diagnosing apparatus according to claim 8 , wherein the differential profile is configured to represent a correspondence between a voltage and a differential capacity of the battery, and

the control unit is configured to determine a plurality of local maximum points in the differential profile, and determine a local maximum point with a largest corresponding differential voltage among the determined plurality of local maximum points, as the main peak.

11 . A battery pack comprising the battery diagnosing apparatus according to claim 1 .

12 . A vehicle comprising the battery diagnosing apparatus according to claim 1 .

13 . A battery diagnosing method comprising:

acquiring a battery profile representing a correspondence between a voltage and a capacity of a battery;

dividing a capacity section of the battery profile into a plurality of sections;

deriving a plurality of target values, wherein each target value of the plurality of target values is related to a differential capacity peak index or a charging capacity ratio index among a plurality of diagnosis indices set in advance and is for a section of the plurality of sections;

comparing a correspondence between the plurality of target values with a preset reference profile that represents a correspondence between a plurality of target indices;

diagnosing a deterioration state of the battery based on a result of the comparison; and

reducing an upper limit current-rate (C-rate), a constant voltage charging time or an upper charge limit voltage set for the battery based on the deterioration state of the battery,

wherein at least one target value of the plurality of target values is related to a charging capacity ratio index.

14 . The battery diagnosing method according to claim 13 , further comprising:

determining a number of a plurality of differential capacity peaks included in a differential profile corresponding to the battery profile, the differential profile representing a correspondence between a voltage and a differential capacity, determine the differential capacity peak index as an area of the differential profile, a voltage of a main peak among the plurality of differential capacity peaks, or a differential capacity of the main peak in a corresponding low-capacity section among the plurality of sections, and determining the charging capacity ratio index in a corresponding high-capacity section among the plurality of sections.

15 . The battery diagnosing method according to claim 13 , wherein diagnosing the deterioration state of the battery based on a result of the comparison:

diagnosing the deterioration state of the battery as a positive negative electrode deterioration state when a target point indicating the correspondence between the plurality of target values is included in the preset reference profile,

diagnosing the deterioration state of the battery as a negative electrode deterioration state when the target point is included in a first region based on the preset reference profile, and

diagnosing the deterioration state of the battery as a positive electrode deterioration state when the target point is included in a second region based on the preset reference profile.

16 . The battery diagnosing method according to claim 15 , wherein diagnosing the deterioration state of the battery based on a result of the comparison includes diagnosing the deterioration state of the battery as an end of life (EOL) state when the target point is included in a third region, and

the third region is preset as a region that exceeds a preset threshold value for each of the plurality of target indices.

17 . The battery diagnosing method according to claim 15 , further comprising:

reducing the upper limit current-rate (C-rate) or the constant voltage charging time set for the battery when the deterioration state of the battery is diagnosed as the positive electrode deterioration state or the positive negative electrode deterioration state.

18 . The battery diagnosing method according to claim 15 , further comprising:

reducing the upper charge limit voltage set for the battery when the deterioration state of the battery is diagnosed as the negative electrode deterioration state or the positive negative electrode deterioration state.

19 . The battery diagnosing method according to claim 13 , wherein dividing the capacity section of the battery profile into the plurality of sections includes dividing the capacity section into a first section and a second section based on a division ratio or a target capacity set in advance.

20 . A non-transitory computer-readable storage medium having stored therein a program that, when executed, causes a computer to execute a battery diagnosing method comprising:

acquiring a battery profile representing a correspondence between a voltage and a capacity of a battery;

dividing a capacity section of the battery profile into a plurality of sections;

deriving a plurality of target values, wherein each target value of the plurality of target values is related to a differential capacity peak index or a charging capacity ratio index among a plurality of diagnosis indices set in advance and is for a section of the plurality of sections;

comparing a correspondence between the plurality of target values with a preset reference profile that represents a correspondence between a plurality of target indices;

diagnosing a deterioration state of the battery based on a result of the comparison; and

reducing an upper limit current-rate (C-rate), a constant voltage charging time or an upper charge limit voltage set for the battery based on the deterioration state of the battery,

wherein at least one target value of the plurality of target values is related to a charging capacity ratio index.