Battery diagnosing apparatus and method

1 . A battery control apparatus, comprising:

a controller; and

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

calculate a voltage deviation between a threshold open circuit voltage (OCV) corresponding to the battery and a measured OCV of the battery;

calculate a resistance deviation between a threshold resistance corresponding to the battery and an estimated resistance based on a measured voltage and a measured current of the battery;

diagnose a state of the battery based on a combination of a voltage increase/decrease pattern for the voltage deviation and a resistance increase/decrease pattern for the resistance deviation; and

adjust a charging and/or discharging condition of the battery based on the diagnosed state of the battery.

2 . The battery control apparatus according to claim 1 ,

wherein the state of the battery is one of a side reaction state, a resistance increase state or a resistance decrease state.

3 . The battery control apparatus according to claim 2 ,

wherein the instructions are configured to cause the controller to diagnose the state of the battery as the side reaction state, the resistance increase state or the resistance decrease state based at least in part on a comparison of the voltage increase/decrease pattern and the resistance increase/decrease pattern.

4 . The battery control apparatus according to claim 3 ,

wherein the instructions are configured to cause the controller to:

diagnose the state of the battery as the side reaction state in response to the voltage increase/decrease pattern and the resistance increase/decrease pattern being identical to each other; and

diagnose the state of the battery as the resistance increase state or the resistance decrease state, in response to the voltage increase/decrease pattern and the resistance increase/decrease pattern being different from each other.

5 . The battery control apparatus according to claim 4 ,

wherein the instructions are configured to cause the controller to diagnose the state of the battery as the resistance increase state, in response to the voltage increase/decrease pattern increasing and the resistance increase/decrease pattern decreasing.

6 . The battery control apparatus according to claim 4 ,

wherein the instructions are configured to cause the controller to diagnose the state of the battery as the resistance decrease state, in response to the voltage increase/decrease pattern decreasing and the resistance increase/decrease pattern increasing.

7 . The battery control apparatus according to claim 2 ,

wherein the side reaction state includes at least one of a first degradation state caused by occurrence of a positive electrode side reaction of the battery and a second degradation state caused by occurrence of a negative electrode side reaction.

8 . The battery control apparatus according to claim 2 ,

wherein the instructions are configured to cause the controller to:

change at least one of a discharge termination voltage and a charge termination voltage for the battery in response to the state of the battery being diagnosed as the side reaction state; and

change at least one of a charge current rate (C-rate) and a discharge C-rate for the battery in response to the state of the battery being diagnosed as the resistance increase state.

9 . The battery control apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to:

at each of a plurality of different time points; calculate the voltage deviation and the resistance deviation;

determine the voltage increase/decrease pattern based on the plurality of calculated voltage deviations; and

determine the resistance increase/decrease pattern based on the plurality of calculated resistance deviations.

10 . The battery control apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to:

calculate the resistance deviation based on a ratio between (i) a difference between a first voltage of the battery measured at a first time point at which the battery is discharged to a discharge termination voltage, and a second voltage of the battery measured at a second time point at which a predetermined time has elapsed from the first time point and (ii) a discharge current of the battery; and

calculate the voltage deviation based on an OCV measured at a third time point later than the second time point.

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

12 . A battery control method, comprising:

measuring a current, a voltage and an OCV of a battery;

estimating a resistance of the battery based on the current and the voltage measured in the measuring step;

calculating, by a controller, a voltage deviation between a threshold OCV corresponding to the battery and the OCV;

calculating, by the controller, a resistance deviation between a threshold resistance corresponding to the battery and the resistance; and

diagnosing a state of the battery based on a combination of a voltage increase/decrease pattern for the voltage deviation and a resistance increase/decrease pattern for the resistance deviation; and

adjusting, by the controller, a charging and/or discharging condition of the battery based on the diagnosed state of the battery.

13 . The battery control apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to diagnose a state of the battery as one of a side reaction state, a resistance increase state or a resistance decrease state based on the voltage increase/decrease pattern for the voltage deviation and the resistance increase/decrease pattern for the resistance deviation, wherein the side reaction state is associated with a first cause of degradation and wherein the resistance increase state is associated with a second cause of degradation that is different from the first cause of degradation.

14 . The battery control apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to perform at least one of an increase to a discharging termination voltage of the battery or a decrease to a charging termination voltage of the battery based on the cause of degradation being a side reaction of a positive or negative electrode of the battery.

15 . The battery control apparatus according to claim 1 ,

wherein the instructions are configured to cause the controller to perform at least one of a decrease to a charge C-rate of the battery or a decrease to a discharge C-rate of the battery based on the cause of degradation being an increase in internal resistance of the battery.

16 . The battery control apparatus according to claim 2 , wherein the instructions are configured to maintain the charging and/or discharging condition of the battery based on the state of the battery being diagnosed as the resistance decrease state.