Battery management apparatus and method

1 . A battery management apparatus, comprising:

a calculating unit configured to calculate a plurality of differential values of a maximum capacity of a battery cell with respect to a voltage of the battery cell;

an analyzing unit configured to perform statistical analysis on the plurality of differential values; and

a determining unit configured to determine the capacity of the battery cell based on the statistical analysis and classify a state of the battery cell as normal or abnormal so as to control a charging or discharging of the battery cell based on the determined state of the battery cell,

wherein the analyzing unit is configured to:

select, as a representative value, a maximum deviation value among deviations of the plurality of differential values between charging/discharging cycles of the battery cell and

perform the statistical analysis on the representative value,

wherein the maximum deviation value among the deviations of the plurality of differential values between the charging/discharging cycles of the battery cell includes a maximum deviation value that does not correspond to peak differential values between the charging/discharging cycles of the battery cell, and

wherein the maximum deviation value is a difference between a value of two different differential curves of the plurality of differential values.

2 . The battery management apparatus of claim 1 , wherein the analyzing unit is further configured to:

calculate an approximation equation for the representative value, and

perform the statistical analysis on a coefficient of the approximation equation.

3 . The battery management apparatus of claim 2 , wherein the analyzing unit is further configured to perform K-means clustering on the coefficient of the approximation equation.

4 . The battery management apparatus of claim 3 , wherein the determining unit is further configured to determine that the capacity of the battery cell is normal when the battery cell belongs to a predetermined cluster among a plurality of clusters.

5 . The battery management apparatus of claim 4 , wherein the predetermined cluster comprises an absolute value of a gradient of the approximation equation for the representative value is less than a reference value.

6 . The battery management apparatus of claim 4 , further comprising a storing unit that is configured to store information about the plurality of clusters.

7 . The battery management apparatus of claim 4 , wherein the determining unit is further configured to determine the capacity of the battery cell after performing charging/discharging of the battery cell up to a preset number of cycles, when the battery cell does not belong to the predetermined cluster.

8 . The battery management apparatus of claim 2 , wherein the approximation equation is a primary or quadratic polynomial.

9 . A battery management method comprising:

calculating a plurality of differential values of a maximum capacity of a battery cell with respect to a voltage of the battery cell;

selecting, as a representative value, a maximum deviation value among deviations of the plurality of differential values between charging/discharging cycles of the battery cell;

performing statistical analysis on the plurality of differential values;

determining the capacity of the battery cell based on the statistical analysis;

classifying a state of the battery cell as normal or abnormal based on the determined capacity of the battery cell so as to control a charging or discharging of the battery cell based on the determined state of the battery cell,

wherein the performing of the statistical analysis comprises performing statistical analysis on the representative value,

wherein the maximum deviation value among the deviations of the plurality of differential values between the charging/discharging cycles of the battery cell includes a maximum deviation value that does not correspond to peak differential values of the charging/discharging cycles of the battery cell, and

wherein the maximum deviation value is a difference between a value of two different differential curves of the plurality of differential values.

10 . The battery management method of claim 9 , further comprising calculating an approximation equation for the representative value,

wherein the performing of the statistical analysis comprises performing statistical analysis on a coefficient of the approximation equation.

11 . The battery management method of claim 10 , further comprising performing K-means clustering on the coefficient of the approximation equation.

12 . The battery management method of claim 11 , further comprising determining that the capacity of the battery cell is normal when the battery cell belongs to a predetermined cluster among a plurality of clusters.