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EP-4564645-B1 - BATTERY MANAGEMENT APPARATUS AND METHOD

EP4564645B1EP 4564645 B1EP4564645 B1EP 4564645B1EP-4564645-B1

Inventors

  • KIM, HWA SU

Dates

Publication Date
20260513
Application Date
20240830

Claims (15)

  1. A battery management apparatus comprising: a temperature sensor (110), and a processor (130), a heat management module (120), characterised in that the temperature sensor (110) is configured to measure a temperature for each section of each battery cell (BAT) included in a battery module; the heat management module (120) is configured to control a temperature of a battery cell (BAT) or the temperature for each section of each battery cell (BAT); the processor (130) is configured to: calculate a maximum average slope value (gCell1~gCellN) for each battery cell (BAT) which is a maximum value among a plurality of average temperature slopes for each section of each battery cell (BAT), wherein the maximum average slope value corresponds to a maximum value among a plurality of average temperature deviations with nearby sections for respective sections of each battery cell (BAT), and perform temperature control via the heat management module (120) or charging current control on a weak battery cell (BAT) based on the maximum average slope values (gCell1~gCellN) of a plurality of battery cells (BAT).
  2. The battery management apparatus of claim 1, wherein, if a maximum average slope value (max(gCell1~gCellN)) among the maximum average slope values (gCell1~gCellN) of the plurality of battery cells (BAT) is greater than a specified threshold lower limit temperature value (Threshold_low), the processor (130) is configured to perform the temperature control or the charging current control on the weak battery cell (BAT) corresponding to a battery cell (BAT) of which the maximum value among the plurality of average temperature deviations with nearby sections for respective sections is greatest.
  3. The battery management apparatus of claim 2, wherein, when performing the charging current control, the processor (130) is configured to perform current reduction control using a difference value between the maximum average slope value (max(gCell1~gCellN)) and a specified threshold upper limit temperature value (Threshold_high).
  4. The battery management apparatus of claim 3, wherein, when performing the current reduction control, the processor (130) is configured to stop charging without performing current reduction control if a value obtained by subtracting the maximum average slope value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) is 1 and a weight value (Weighted_factor) is 0.
  5. The battery management apparatus of claim 4, wherein the weight value (Weighted_factor) corresponds to a value obtained by subtracting the maximum average slope value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) and taking a log of a resultant value.
  6. The battery management apparatus of claim 4 or 5, wherein, when performing the current reduction control, the processor (130) is configured to not immediately control a charging current to increase by only changing the weight value to decrease in a range of the specified threshold upper limit temperature value (Threshold_high) and the specified threshold lower limit temperature (Threshold_low) even if the temperature of the battery cell (BAT) is reduced by a reduction of the charging current.
  7. The battery management apparatus of claim 6, wherein, when performing the current reduction control, the processor (130) is configured to finishe the stopping of the charging and re-performs charging with an original maximum current by increasing the charging current if the weight value (Weighted_factor) is reset to 1 as the maximum average slope value (max(gCell1~gCellN)) is smaller than the specified threshold lower limit temperature (Threshold_low).
  8. The battery management apparatus of claim 4, wherein, when performing the current reduction control, the processor (130) is configured to perform charging while continuously maintaining an already reduced current rather than stopping the charging when a value obtained by subtracting the maximum average slope value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) is not 1 and the weight value is not 0.
  9. A battery management method characterised in that : calculating, by a processor (130), with respect to a plurality of battery cells (BAT) included in a battery module, each of the plurality of battery cells (BAT) including a plurality of sections, a maximum average slope value (gCell1 to gCellN) for each of the plurality of battery cells (BAT) which is a maximum average slope value among a plurality of average temperature slopes for respective sections of each of the plurality of battery cell (BAT), wherein the maximum average slope value corresponds to a maximum average temperature deviation value among a plurality of average temperature deviation values with nearby sections for respective sections of each of the plurality of battery cell (BAT); and performing, by the processor (130), temperature control or charging current control on a weak battery cell (BAT) based on the maximum average slope values (gCell1 to gCellN) of the plurality of battery cells (BAT).
  10. The battery management method of claim 9, further comprising: calculating, by the processor (130), a maximum average slope value (max(gCell1~gCellN)) among the maximum average slope values (gCell1 to gCellN) of the plurality of battery cells (BAT), wherein, if the maximum average slope value (max(gCell1~gCellN)) of the plurality of battery cells (BAT) is greater than a specified threshold lower limit temperature value (Threshold_low), the processor (130) performs the temperature control or the charging current control on the weak battery cell (BAT) corresponding to a battery cell (BAT) of which the maximum temperature deviation value among the plurality of average temperature deviation values with nearby sections for respective sections is greatest.
  11. The battery management method of claim 10, wherein, in performing the charging current control, the processor (130) performs current reduction control using a difference value between the maximum average slope value (max(gCell1~gCellN)) and a specified threshold upper limit temperature value (Threshold_high).
  12. The battery management method of claim 11, wherein, when performing the current reduction control, the processor (130) stops charging without performing the current reduction control any more when a value obtained by subtracting the maximum average slope value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) is 1 and a weight value (Weighted_factor) is 0.
  13. The battery management method of claim 12, wherein the weight value (Weighted_factor) corresponds to a value obtained by subtracting the maximum average slope value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) and taking a log of a resultant value.
  14. The battery management method of claim 12 or 13, wherein, when performing the current reduction control, the processor (130) does not immediately control a charging current to increase by only changing the weight value to decrease in a range of the specified threshold upper limit temperature value (Threshold_high) and the specified threshold lower limit temperature value (Threshold_low) even if the temperature of the battery cell (BAT) is reduced by reduction of the charging current.
  15. The battery management method of claim 12, wherein, when performing the current reduction control, the processor (130) (130) is configured to perform charging while continuously maintaining an already reduced current if a value obtained by subtracting the maximum value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) is not 1 and the weight value is not 0.

Description

BACKGROUND 1. Field Aspects of embodiments of the present disclosure relate to a battery management apparatus and method capable of preventing unbalanced charging between battery cells. 2. Description of the Related Art In general, a lifetime of a battery pack (or a cell to pack (CTP)) or battery module composed of one or more battery cells is determined by a weak battery cell (or a worst cell) with a reduced lifetime due to fastest degradation among the battery cells included in the battery module (or the battery pack). For example, as a battery is used, a deviation occurs between the battery cells, and the deviation accelerates the degradation of a specific cell (weak battery cell), resulting in ultimately shortening the lifetime of the battery module (or the battery pack) due to this battery cell (i.e., the weak battery cell) (even when the remaining batter cells are still in a sufficiently usable state). Therefore, in order to extend the lifetime of the battery module (or the battery pack) composed of the plurality of battery cells, there is a need for a technology of preventing unbalanced charging between the battery cells. In addition, as a capacity of the battery cell increases, the unbalanced charging between sections (or areas) occurs even in a single battery cell, and thus there is a need for a technology for preventing unbalanced charging between sections of battery cells. US2021/273270A1 describes a battery system including a battery module that includes a plurality of cells. A management unit manages charging-discharging of the battery module and a temperature sensor inside the battery module. The management unit estimates a maximum temperature of an inside of a cell in the battery module based on a measured temperature in the battery module, and controls, during charging-discharging of the battery module, a charging-discharging current of the battery module and/or cooling of the battery module in such a way that the estimated maximum temperature does not exceed an upper limit temperature. SUMMARY The present invention is directed to providing a battery management apparatus and method capable of preventing unbalanced charging between battery cells in a battery module (or a battery pack) composed of a plurality of battery cells. In addition, the present invention is directed to providing a battery management apparatus and method capable of preventing unbalanced charging between sections in a single battery cell. According to an aspect of the present invention, there is provided a battery management apparatus including a temperature sensor configured to measure a temperature for each section of each battery cell included in a battery module, a heat management module configured to control a temperature of the battery cell or the temperature for each section of each battery cell, and a processor, wherein the processor is configured to: calculate a maximum average slope value (gCell1 to gCellN) for each battery cell which is a maximum value among a plurality of average temperature slopes for respective sections of each battery cell, wherein the maximum average slope value corresponds to a maximum value among a plurality of average temperature deviations with nearby sections for respective sections of each battery cell, and perform temperature control or charging current control in a specific manner on a weak battery cell based on the maximum average slope values (gCell1 to gCellN) of a plurality of battery cells. When a maximum value (max(gCell1~gCellN)) among the maximum average slope values (gCell1 to gCellN) of a plurality of battery cells is greater than a specified threshold lower limit temperature value (Threshold_low), the processor may perform the temperature control or the charging current control on the weak battery cell corresponding to a battery cell of which the maximum value among the plurality of average temperature deviations with nearby sections for respective sections is the greatest. When performing the charging current control in a specified manner, the processor may perform current reduction control using a difference value between the maximum value (max(gCell1~gCellN)) and a specified threshold upper limit temperature value (Threshold_high). When performing the current reduction control, the processor may stop charging with not performing current reduction control any more when a value obtained by subtracting the maximum value (max(gCell1~gCellN)) from the threshold upper limit temperature value (Threshold_high) is 1 and thus a weight value (Weighted_factor) is 0. The weight value (Weighted_factor) may correspond to a value (i.e., Logx(Threshold_high-the maximum slope average value)) obtained by subtracting the maximum value (max(gCell1~gCellN)) from the specified threshold upper limit temperature value (Threshold_high) and taking a log for a resultant value. When performing the current reduction control, the processor may not immediately control a charging current to increase