CPC H02J 7/00712 (2020.01) [G01R 31/367 (2019.01); G01R 31/3842 (2019.01); G01R 31/389 (2019.01); G01R 31/396 (2019.01); H01M 10/48 (2013.01); H02J 7/0013 (2013.01); H02J 7/0047 (2013.01)] | 16 Claims |
1. A battery management apparatus, comprising:
a voltage measurer configured to measure a voltage of a battery cell;
a current measurer configured to measure a current of the battery cell; and
a controller connected to the voltage measurer and the current measurer, the controller being configured to:
receive a voltage value for the voltage measured by the voltage measurer;
receive a current value for the current measured by the current measurer;
estimate an electricity amount of the battery cell, based on the received current value;
obtain an electricity amount-voltage curve for the battery cell, based on the estimated electricity amount and the received voltage value;
extract a plurality of inflection points from the obtained electricity amount-voltage curve;
classify inflection points at which a derivative curve of the electricity amount-voltage curve has an upwardly convex shape, among the plurality of inflection points in the electricity amount-voltage curve, as a first inflection point group;
extract an electricity amount of a specific point satisfying a predetermined condition among the inflection points in the first inflection point group of the plurality of extracted inflection points;
calculate a first function value for the extracted electricity amount of the specific point from a derivative of the electricity amount-voltage curve;
extract a second function value corresponding to the first function value from a pre-stored reference electricity amount-voltage table; and
calculate a resistance change rate of a present resistance with respect to an initial resistance of the battery cell, based on the first function value and the second function value.
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