Apparatus for diagnosing battery of vehicle, battery diagnostic method thereof, and vehicle system comprising same

An apparatus for diagnosing a battery of a vehicle, the apparatus comprising:

• a voltage sensor configured to measure voltage of each of a plurality of battery cells within the battery;
• and
• a processor configured to perform low voltage diagnosis with respect to the battery based on a cell voltage measured by the voltage sensor,
• wherein the processor comprises:
• a first diagnosis module configured to, based on the cell voltage satisfying a preset condition, determine that the battery is at a low voltage state, and
• a second diagnosis module configured to (i) operate independently from the first diagnosis module and, (ii) based on a minimum cell voltage among voltages of the plurality of cells satisfying the preset condition, determine that the battery is at the low voltage state,
• wherein first diagnosis module is further configured to:
• determine that the cell voltage satisfies the diagnosis start condition, based on the cell voltage being (i) maintained at or greater than a first reference time and (ii) greater than or equal to a first reference voltage and less than or equal to a second reference voltage,
• determine that the battery satisfies the preset diagnostic condition, based on the cell voltage being (i) maintained at or greater than a preset second reference time and (ii) less than the first reference voltage, and
• determine that the battery is at the low voltage state based on the preset diagnostic condition being satisfied.

A vehicle battery diagnostic method performed by a processor based on a plurality of cell voltages measured by a voltage sensor, comprising:

• monitoring the plurality of cell voltages;
• determining whether a cell voltage among the plurality of cell voltages satisfies a diagnosis start condition;
• determining, based on the cell voltage satisfying the diagnosis start condition, whether the cell voltage satisfies a preset diagnostic condition;
• and
• determining, based on the cell voltage satisfying the diagnostic condition, that the battery is at a low voltage state,
• wherein determining whether the diagnosis start condition is satisfied comprises:
• determining, based on the cell voltage being (i) maintained at or greater than a preset first reference time and (ii) equal to or greater than a first reference voltage and less than or equal to a second reference voltage, that the cell voltage satisfies the diagnosis start condition, and
• wherein determining whether the diagnostic condition is satisfied comprises:
• determining, based on the cell voltage being (i) maintained at or greater than a preset second reference time and (ii) less than the first reference voltage, that the cell voltage satisfies the diagnostic condition.

A vehicle system comprising:

• a battery;
• a load operated based on energy supplied from the battery;
• a relay disposed between the battery and the load;
• and
• a battery diagnostic apparatus,
• wherein the battery diagnostic apparatus comprises:
• a voltage sensor configured to measure voltage of each of a plurality of battery cells within the battery;
• and
• a processor configured to perform low voltage diagnosis with respect to the battery based on a cell voltage measured by the voltage sensor,
• wherein the processor is configured to:
• based on the cell voltage satisfying a diagnosis start condition, determine whether the cell voltage satisfies a preset diagnostic condition, and
• based on the cell voltage satisfying the diagnostic condition, determine that the battery is at a low voltage state,
• wherein the processor is further configured to:
• determine that the cell voltage satisfies the diagnosis start condition, based on the cell voltage being (i) maintained at or greater than a first reference time and (ii) greater than or equal to a first reference voltage and less than or equal to a second reference voltage,
• determine that the battery satisfies the preset diagnostic condition, based on the cell voltage being (i) maintained at or greater than a preset second reference time and (ii) less than the first reference voltage, and
• determine that the battery is at the low voltage state based on the preset diagnostic condition being satisfied.