Battery diagnostic device and method of operating the same

Abstract

A battery diagnostic apparatus according to embodiments disclosed in the present document can include a pulse application unit that applies a current pulse to a battery, and a controller that acquires a first voltage corresponding to the current pulse, calculates a frequency-specific impedance of the battery based on the current pulse and the first voltage via a Fourier transform, and diagnoses whether an abnormal battery cell is included in the battery based on first information of the battery related to the frequency-specific impedance of the battery.

Description

Technical Field

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2023-0178063, filed with the Korean Intellectual Property Office on December 8, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The embodiments disclosed herein relate to a battery diagnostic device and its operating method. Background Technology

[0005] Recently, research and development of rechargeable batteries have been actively pursued. Here, rechargeable batteries, as rechargeable / dischargeable batteries, can include all conventional nickel (Ni) / cadmium (Cd) batteries, Ni / metal hydride (MH) batteries, and more recently, lithium-ion batteries. Among rechargeable batteries, lithium-ion batteries have a significantly higher energy density than conventional Ni / Cd and Ni / MH batteries. Furthermore, lithium-ion batteries can be manufactured to be small and lightweight, enabling their use as power sources for mobile devices. Recently, the application of lithium-ion batteries has expanded to power electric vehicles, attracting attention as a next-generation energy storage medium.

[0006] Batteries are managed through a Battery Management System (BMS). The BMS measures or predicts the battery's state and thus diagnoses whether the battery is abnormal. On the other hand, battery behavior can change depending on factors such as temperature, state of charge (SOC), and state of health (SOH), making it difficult to accurately diagnose abnormalities. Summary of the Invention

[0007] Technical issues

[0008] The embodiments disclosed herein are intended to provide a battery diagnostic apparatus and a method of operation thereof, wherein the frequency-specific impedance of a cell in a battery can be calculated and the battery can be diagnosed based on the calculated impedance.

[0009] The embodiments disclosed herein are intended to provide a battery diagnostic device and a method of operation thereof, wherein the frequency-specific impedance of the battery can be calculated based on the response of a pulse applied to the battery.

[0010] The technical problems of the embodiments disclosed herein are not limited to those described above, and other unmentioned technical problems will be clearly understood by those skilled in the art based on the following description.

[0011] Technical solutions

[0012] A battery diagnostic apparatus according to an embodiment disclosed herein includes: a pulse application unit configured to apply a current pulse to a battery; and a controller configured to: obtain a first voltage corresponding to the current pulse; calculate a frequency-specific impedance of the battery based on the current pulse and the first voltage via Fourier transform; and diagnose whether the battery contains abnormal battery cells based on first information of the battery related to the frequency-specific impedance of the battery.

[0013] In an implementation, the pulse application unit can be configured to apply at least one of a charging current pulse and a discharging current pulse to the battery.

[0014] In an implementation, the pulse application unit may also be configured to alternately apply at least two of the following signals to the battery: a charging current pulse, a pause current pulse, and a discharging current pulse.

[0015] In an implementation, the first information may include at least one of the following: the real part of a frequency-specific impedance, the imaginary part of a frequency-specific impedance, the amplitude of a frequency-specific impedance, or the phase of a frequency-specific impedance.

[0016] In an implementation, the controller may also be configured to: calculate a first difference based on the difference between first information at a first frequency and first information at multiple frequencies different from the first frequency; and diagnose whether the battery contains abnormal battery cells based on the first difference at multiple frequencies.

[0017] In an implementation, the controller may also be configured to: calculate a first difference for each of a plurality of battery cells included in the battery; calculate an average of the first differences for each of the plurality of battery cells; and diagnose battery abnormalities based on the average of the first differences and the first differences for each of the plurality of battery cells.

[0018] In an implementation, the controller may also be configured to: calculate the deviation between the average of the first difference and the first difference of each of the plurality of battery cells; and diagnose that the battery includes abnormal battery cells when the deviation is greater than or equal to a preset value.

[0019] In some implementations, the controller can also be configured to calculate deviations within a set frequency range.

[0020] In an implementation, the first frequency may be the lowest frequency among the frequencies from which the impedance is calculated.

[0021] In an implementation, the first frequency may be the highest frequency among the frequencies from which the impedance is calculated.

[0022] An operating method of a battery diagnostic device according to an embodiment disclosed herein includes: applying a current pulse to a battery; obtaining a first voltage corresponding to the current pulse; calculating a frequency-specific impedance of the battery based on the current pulse and the first voltage using a Fourier transform; and diagnosing whether the battery contains abnormal battery cells based on first information of the battery related to the frequency-specific impedance of the battery.

[0023] In an implementation, applying a current pulse to the battery may include applying at least one of a charging current pulse and a discharging current pulse to the battery.

[0024] In one implementation, applying a current pulse to the battery may include applying at least two of the following signals alternately: a charging current pulse, a rest current pulse, and a discharging current pulse.

[0025] In an implementation, the first information may include at least one of the following: the real part of a frequency-specific impedance, the imaginary part of a frequency-specific impedance, the amplitude of a frequency-specific impedance, or the phase of a frequency-specific impedance.

[0026] In one implementation, diagnosing whether a battery contains an abnormal battery cell based on first information about the battery that is related to the frequency-specific impedance of the battery may include: calculating a first difference based on the difference between the first information at a first frequency and first information at multiple frequencies different from the first frequency; and diagnosing whether a battery contains an abnormal battery cell based on the first difference at multiple frequencies.

[0027] In one implementation, diagnosing whether a battery contains an abnormal battery cell based on first information about the battery related to the frequency-specific impedance of the battery may include: calculating a first difference for each of a plurality of battery cells included in the battery; calculating an average of the first differences for each of the plurality of battery cells; and diagnosing the abnormality of the battery based on the average of the first differences and the first differences for each of the plurality of battery cells.

[0028] In one implementation, diagnosing a battery abnormality based on the average of the first difference and the first difference of each of the plurality of battery cells may include: calculating the deviation between the average of the first difference and the first difference of each of the plurality of battery cells; and diagnosing that the battery includes an abnormal battery cell when the deviation is greater than or equal to a preset value.

[0029] In an implementation, calculating the deviation between the average value of the first difference and the first difference of each of the plurality of battery cells may include calculating the deviation within a set frequency range.

[0030] In an implementation, the first frequency may be the highest frequency among the frequencies from which the impedance is calculated.

[0031] In an implementation, the first frequency may be the highest frequency among the frequencies from which the impedance is calculated.

[0032] Beneficial effects

[0033] The battery diagnostic apparatus and its operating method according to the embodiments disclosed herein can accurately diagnose batteries.

[0034] The battery diagnostic apparatus and its operating method according to the embodiments disclosed herein can calculate the frequency-specific impedance using Fourier transform and diagnose the battery based on the calculated frequency-specific impedance.

[0035] The battery diagnostic apparatus and its operating method according to the embodiments disclosed herein can determine whether there are defective cells in a battery.

[0036] In addition, various effects that can be directly or indirectly identified through this document can be provided. Attached Figure Description

[0037] Figure 1 This is a block diagram of a battery diagnostic device according to the embodiments disclosed herein.

[0038] Figure 2 An example of applying a pulse to a battery diagnostic device according to an embodiment disclosed herein is shown.

[0039] Figure 3 An example is shown of the results of calculating frequency-specific impedance using a battery diagnostic apparatus according to an embodiment disclosed herein.

[0040] Figure 4 An example is shown of determining the presence of abnormal battery cells in a battery using a battery diagnostic apparatus according to an embodiment disclosed herein.

[0041] Figure 5 This is a view illustrating the operation method of a battery diagnostic device according to an embodiment disclosed herein.

[0042] Figures 6 to 8 This is a flowchart illustrating in detail the operation method of a battery diagnostic device according to the embodiments disclosed herein.

[0043] Figure 9 This is a block diagram illustrating the hardware configuration of a computing system for performing an operation method of a battery diagnostic device according to an embodiment disclosed herein. Detailed Implementation

[0044] In the following, the embodiments disclosed herein will be described in detail with reference to exemplary accompanying drawings. When adding reference numerals to components in each drawing, it should be noted that even if the same component is shown in different drawings, the same component will be labeled with the same reference numerals as much as possible. Furthermore, in describing the embodiments disclosed herein, detailed descriptions of related known configurations or functions will be omitted if it is determined that such detailed descriptions interfere with the understanding of the embodiments disclosed herein.

[0045] To describe components of the embodiments disclosed herein, terms such as first, second, A, B, (a), (b), etc., may be used. These terms are used only to distinguish one component from another and do not limit the components to their nature, sequence, order, etc. The terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art, unless otherwise defined. Terms defined in general dictionaries should be interpreted as having the same meaning as in the context of the related art and should not be interpreted as having an ideal or exaggerated meaning unless clearly defined in this application.

[0046] Figure 1 A battery diagnostic device according to an embodiment disclosed herein is shown.

[0047] Reference Figure 1 The battery diagnostic apparatus 100 according to the embodiments disclosed herein may include a pulse application unit 110 and a controller 120.

[0048] The battery diagnostic device 100 can be one of various electronic devices used for diagnosing or testing a battery. For example, the battery diagnostic device 100 can be a pulse analyzer. The pulse analyzer can be a device for diagnosing whether a battery is abnormal based on the response to a pulse applied to the battery. The pulse analyzer can be included in the BMS in a vehicle, or it can be implemented as a separate external device distinct from the BMS in the vehicle. The pulse analyzer can also include a pulse generator for pulse generation, but this is only an example, and the pulse generator can be implemented as a separate external device. In the latter case, the battery diagnostic device 100 can receive the response from the battery to a pulse applied to the battery by the pulse generator and diagnose whether the battery is abnormal based on that response.

[0049] According to another embodiment, the battery diagnostic device 100 may be included in a device for charging / discharging testing, such as a server, cloud server, or charge / discharge cycler, or may be included in various devices for diagnosing or testing batteries.

[0050] The pulse application unit 110 can apply current pulses to the battery. For example, the pulse application unit 110 can apply multiple current pulses to the battery.

[0051] According to one embodiment, the pulse application unit 110 can apply at least one of a charging pulse and a discharging pulse to the battery. In another example, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery.

[0052] According to one embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery, and there may be no pause period between the charging pulses and discharging pulses. According to another embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery while setting a pause period between the charging pulses and discharging pulses.

[0053] According to the embodiment, the pulse application unit 110 can continuously apply charging pulses to the battery. For example, the pulse application unit 110 can apply charging pulses to the battery, set a rest period, and apply charging pulses again, thereby continuously applying charging pulses during the set period.

[0054] According to the embodiment, the pulse application unit 110 can continuously apply discharge pulses to the battery. For example, the pulse application unit 110 can apply discharge pulses to the battery, set a rest period, and apply discharge pulses again, thereby continuously applying discharge pulses during the set period.

[0055] According to the embodiment, the pulse application unit 110 can alternately apply charging pulses, pause pulses, and discharge pulses set according to specific conditions to the battery. For example, the pulse application unit 110 applies pulses to the battery in a manner that applies a charging pulse for 0.1 seconds, has a pause period of 0.1 seconds, applies a discharge pulse for 0.1 seconds, and repeats the aforementioned process. However, this disclosure is not limited to this, and the pulse application unit 110 can apply pulses to the battery by determining the following: the application time of the charging pulse, whether to apply a charging pulse, whether to pause, the pause period, the application time of the discharge pulse, and whether to apply a discharge pulse.

[0056] According to the embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses multiple times. For example, the pulse application unit 110 can alternately apply charging pulses and discharging pulses three to ten times. However, the present disclosure is not limited thereto, and the pulse application unit 110 can alternately apply charging pulses and discharging pulses n times (n is a natural number).

[0057] According to the embodiment, the pulse application unit 110 can apply charging pulses and discharging pulses as current.

[0058] Such a pulse application unit 110 can receive pulses generated by an external device and apply the received pulses to the battery, and can also generate pulses based on the control of the controller 120 and apply the generated pulses to the battery.

[0059] Figure 2 An example of applying a pulse to a battery diagnostic device according to an embodiment disclosed herein is shown.

[0060] Reference Figure 2 The pulse application unit 110 of the battery diagnostic device 100 can apply pulses to the battery. Although in Figure 2 The pulse application unit 110 alternately applies charging pulses and discharging pulses, but the present disclosure is not limited thereto.

[0061] According to the embodiment, the pulse application unit 110 can apply various pulses to the battery by means of: repetition of charging pulses and discharging pulses, repetition of charging pulses and pauses, repetition of discharging pulses and pauses, repetition of charging pulses, pauses and discharging pulses, etc.

[0062] Refer again Figure 1 The controller 120 can obtain a first voltage corresponding to the current pulse. For example, the controller 120 can obtain a voltage corresponding to either the charging pulse or the discharging pulse of the current pulse as the first voltage.

[0063] According to an embodiment, when the pulse application unit 110 applies a plurality of current pulses, the controller 120 can obtain a first voltage corresponding to one or all of the plurality of current pulses. In another example, the controller 120 can obtain a voltage response corresponding to each of the plurality of current pulses, and obtain all or some of the obtained voltage responses as the first voltage. For example, the controller 120 can obtain the voltage corresponding to a discharge pulse among the plurality of current pulses as the first voltage, obtain the voltage corresponding to a charging pulse among the plurality of current pulses as the first voltage, or obtain the voltage corresponding to each of the charging pulse and discharge pulse included in the plurality of current pulses as the first voltage.

[0064] According to one embodiment, the controller 120 can calculate the average value of the first voltage corresponding to at least one current pulse as the average voltage. For example, the controller 120 can extract at least one current pulse from a plurality of current pulses according to a standard, and calculate the average value of the first voltage corresponding to the extracted at least one current pulse as the average voltage. In another embodiment, the controller 120 can calculate the average value of the first voltage corresponding to all or some of the current pulses among the plurality of current pulses as the average voltage. According to another embodiment, the controller 120 can calculate the average voltage by calculating the average value of the first voltage corresponding to a low-noise current pulse among the plurality of current pulses.

[0065] According to the implementation, when the charging pulse and discharging pulse are repeated 5 times, the controller 120 can obtain 5 first voltages as voltage responses corresponding to the 5 discharging pulses, and can calculate the average value of all or some of the 5 first voltages as the average voltage. That is, the controller 120 can obtain the first voltages corresponding to one or more current pulses, and diagnose the battery based on the average voltage of the obtained first voltages. However, the operation of calculating the average voltage of the first voltages corresponding to multiple current pulses as a noise removal operation can be omitted.

[0066] The controller 120 can calculate the frequency-specific impedance of the battery based on the current pulse and a first voltage using a Fourier transform. For example, the Fourier transform may include a Fast Fourier Transform (FFT) or a Discrete Fourier Transform (DFT).

[0067] According to one implementation, the controller 120 can perform a Fourier transform on the current pulse, perform a Fourier transform on the first voltage, and divide the Fourier-transformed first voltage by the Fourier-transformed current pulse to calculate the Fourier-transformed impedance. The controller 120 can calculate a frequency-specific impedance based on the Fourier-transformed impedance.

[0068] The controller 120 can diagnose whether the battery contains abnormal battery cells based on first information about the battery related to its frequency-specific impedance. For example, the first information may include at least one of the following: the real part of the frequency-specific impedance, the imaginary part of the frequency-specific impedance, the amplitude of the frequency-specific impedance, or the phase of the frequency-specific impedance. According to an embodiment, the controller 120 can diagnose whether the battery contains abnormal battery cells based on the real part of the frequency-specific impedance.

[0069] The controller 120 can calculate a first difference based on the difference between first information at a first frequency and first information at multiple frequencies different from the first frequency. For example, the first frequency could be the minimum frequency among the frequencies used to calculate the impedance. In another example, the first frequency could be the maximum frequency among the frequencies used to calculate the impedance. That is, the first frequency could be a reference frequency among the frequencies used to calculate the impedance.

[0070] The controller 120 can diagnose whether the battery contains abnormal battery cells based on a first difference at multiple frequencies. For example, the controller 120 can calculate the difference between the real part of the impedance at the first frequency and the real parts of the impedance at multiple frequencies, and diagnose whether abnormal battery cells are included based on the calculated difference.

[0071] According to an implementation, the battery may include a plurality of battery cells. The controller 120 may calculate a first difference for each of the plurality of battery cells included in the battery, and calculate an average of the first differences for each of the plurality of battery cells. The controller 120 may also diagnose battery abnormalities based on the average of the first differences and the first differences for each of the plurality of battery cells. For example, the controller 120 may also diagnose whether the battery includes abnormal battery cells based on the average of the first differences and the first differences for each of the plurality of battery cells.

[0072] According to the implementation, the controller 120 can calculate the deviation between the average value of the first difference and the first difference of each of the plurality of battery cells, and when the deviation is greater than or equal to a preset value, diagnose that the battery includes abnormal battery cells.

[0073] According to one implementation, the controller 120 can calculate the deviation within a set frequency range for diagnostic purposes. For example, the set frequency range may include a range from 0.5 Hz to 50 Hz.

[0074] Figure 3 An example is shown of the results of calculating frequency-specific impedance using a battery diagnostic apparatus according to an embodiment disclosed herein.

[0075] Reference Figure 3 The battery diagnostic device 100 can calculate the frequency-specific impedance of the battery cells included in the battery to identify the Nyquist plot. However, identifying the Nyquist plot is not a necessary feature, and the battery diagnostic device 100 can identify the real and imaginary parts of the frequency-specific impedance of the battery cells.

[0076] The controller 120 of the battery diagnostic device 100 can identify the impedance 310 of the battery cell at a first frequency. Although in Figure 3The diagram shows that the minimum frequency in the frequency range used to calculate the impedance is the first frequency, but this disclosure is not limited thereto. Controller 120 can identify the impedance 320 of the battery cell at multiple frequencies other than the first frequency.

[0077] The controller 120 can calculate a first difference 330 between first information related to the impedance of the battery cell at a first frequency and first information related to the impedance of the battery cell at multiple frequencies different from the first frequency. For example, the controller 120 can calculate the first difference for each of the multiple frequencies. Although in Figure 3 The first information shown includes the real part of the impedance, but this disclosure is not limited thereto. Although in Figure 3 The diagram shows the calculation of the first difference for two frequencies, but this disclosure is not limited thereto, and the controller 120 can calculate the first difference for all frequencies for which the impedance has been calculated.

[0078] Although Figure 3 The present invention illustrates a frequency-specific impedance of a battery cell and calculates a first difference for multiple frequencies of a battery cell, but the present disclosure is not limited thereto, and the controller 120 may calculate a frequency-specific impedance for each of the plurality of battery cells and calculate a first difference for each of the plurality of battery cells at multiple frequencies.

[0079] Figure 4 An example is shown of determining the presence of abnormal battery cells in a battery using a battery diagnostic apparatus according to an embodiment disclosed herein.

[0080] Reference Figure 4 According to the embodiments disclosed herein, the controller 120 of the battery diagnostic device 100 can calculate a first frequency difference 510 for each of a plurality of battery cells.

[0081] The controller 120 can calculate the average of the first differences for each of the plurality of battery cells, and calculate the deviation 520 between the average of the first differences and the first differences of each of the plurality of battery cells. For example, the controller 120 can calculate the average of the first differences for each frequency (the frequency at which the first differences 510 for each of the plurality of battery cells are calculated), and calculate the deviation between the average of the first differences and the first differences of each battery cell for each calculated frequency. In another example, the deviation can be calculated based on the difference, can be calculated based on the standard deviation of a normal distribution, or can be calculated in various ways such as root mean square (RMS), least squares mean (LSM), etc.

[0082] The controller 120 can determine whether a faulty battery cell is included among the plurality of battery cells based on a deviation 520 of a first difference among each of the plurality of battery cells. In other words, the controller 120 can determine whether a faulty battery cell is included in the battery based on a deviation 520 of a first difference among each of the plurality of battery cells. According to an embodiment, the controller 120 can calculate the deviation within a set frequency range 530 and diagnose whether a faulty battery cell is included in the battery.

[0083] Therefore, the battery diagnostic device 100 according to the embodiments disclosed herein can accurately diagnose the battery.

[0084] The battery diagnostic device 100 according to the embodiments disclosed herein can calculate the frequency-specific impedance using Fourier transform and diagnose the battery based on the calculated frequency-specific impedance.

[0085] The battery diagnostic apparatus 100 according to the embodiments disclosed herein can determine whether there are defective cells in the battery.

[0086] Figure 5 This is a view illustrating an operation method of a battery diagnostic device according to an embodiment disclosed herein. According to the embodiment, Figure 5 The operations shown can be performed by Figure 1 The battery diagnostic device 100 is executed.

[0087] Reference Figure 5 In operation 510, the pulse application unit 110 can apply a current pulse to the battery. For example, the pulse application unit 110 can apply multiple current pulses to the battery.

[0088] According to one embodiment, the pulse application unit 110 can apply at least one of a charging pulse and a discharging pulse to the battery. In another example, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery.

[0089] According to one embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery, and there may be no pause period between the charging pulses and the discharging pulses. According to another embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses to the battery, and a pause period may be provided between the charging pulses and the discharging pulses.

[0090] According to the embodiment, the pulse application unit 110 can continuously apply charging pulses to the battery. For example, the pulse application unit 110 can apply charging pulses to the battery, set a rest period, and apply charging pulses again, thereby continuously applying charging pulses during the set period.

[0091] According to the embodiment, the pulse application unit 110 can continuously apply discharge pulses to the battery. For example, the pulse application unit 110 can apply discharge pulses to the battery, set a rest period, and apply discharge pulses again, thereby continuously applying discharge pulses during the set period.

[0092] According to the embodiment, the pulse application unit 110 can alternately apply charging pulses, pause pulses, and discharge pulses set according to specific conditions to the battery. For example, the pulse application unit 110 applies pulses to the battery in a manner that applies a charging pulse for 0.1 seconds, has a pause period of 0.1 seconds, applies a discharge pulse for 0.1 seconds, and repeats the aforementioned process. However, this disclosure is not limited to this, and the pulse application unit 110 can apply pulses to the battery by determining the following: the application time of the charging pulse, whether to apply a charging pulse, whether to pause, the pause period, the application time of the discharge pulse, and whether to apply a discharge pulse.

[0093] According to the embodiment, the pulse application unit 110 can alternately apply charging pulses and discharging pulses multiple times. For example, the pulse application unit 110 can alternately apply charging pulses and discharging pulses three to ten times. However, the present disclosure is not limited thereto, and the pulse application unit 110 can alternately apply charging pulses and discharging pulses n times (n is a natural number).

[0094] According to the embodiment, the pulse application unit 110 can apply charging pulses and discharging pulses as current.

[0095] In operation 520, controller 120 can obtain a first voltage corresponding to the current pulse. For example, controller 120 can obtain a voltage corresponding to either the charging pulse or the discharging pulse of the current pulse as the first voltage.

[0096] According to an embodiment, when the pulse application unit 110 applies a plurality of current pulses, the controller 120 can obtain a first voltage corresponding to one or all of the plurality of current pulses. In another example, the controller 120 can obtain a voltage response corresponding to each of the plurality of current pulses, and obtain all or some of the obtained voltage responses as the first voltage. For example, the controller 120 can obtain the voltage corresponding to a discharge pulse among the plurality of current pulses as the first voltage, obtain the voltage corresponding to a charging pulse among the plurality of current pulses as the first voltage, or obtain the voltage corresponding to each of the charging pulse and discharge pulse included in the plurality of current pulses as the first voltage.

[0097] According to one embodiment, the controller 120 can calculate the average value of the first voltage corresponding to at least one current pulse as the average voltage. For example, the controller 120 can extract at least one current pulse from a plurality of current pulses according to a standard, and calculate the average value of the first voltage corresponding to the extracted at least one current pulse as the average voltage. In another embodiment, the controller 120 can calculate the average value of the first voltage corresponding to all or some of the current pulses among the plurality of current pulses as the average voltage. According to another embodiment, the controller 120 can calculate the average voltage by calculating the average value of the first voltage corresponding to a low-noise current pulse among the plurality of current pulses.

[0098] According to the implementation, when the charging pulse and discharging pulse are repeated 5 times, the controller 120 can obtain 5 first voltages as voltage responses corresponding to the 5 discharging pulses, and can calculate the average value of all or some of the 5 first voltages as the average voltage. That is, the controller 120 can obtain the first voltages corresponding to one or more current pulses, and diagnose the battery based on the average voltage of the obtained first voltages. However, the operation of calculating the average voltage of the first voltages corresponding to multiple current pulses as a noise removal operation can be omitted.

[0099] In operation 530, controller 120 can calculate the frequency-specific impedance of the battery based on the current pulse and the first voltage using a Fourier transform. For example, the Fourier transform may include an FFT or a DFT.

[0100] According to one implementation, the controller 120 can perform a Fourier transform on the current pulse, perform a Fourier transform on the first voltage, and divide the Fourier-transformed first voltage by the Fourier-transformed current pulse to calculate the Fourier-transformed impedance. The controller 120 can calculate a frequency-specific impedance based on the Fourier-transformed impedance.

[0101] In operation 540, controller 120 can diagnose whether the battery contains abnormal battery cells based on first information about the battery related to its frequency-specific impedance. For example, the first information may include at least one of the following: the real part of the frequency-specific impedance, the imaginary part of the frequency-specific impedance, the amplitude of the frequency-specific impedance, or the phase of the frequency-specific impedance. According to an embodiment, controller 120 can diagnose whether the battery contains abnormal battery cells based on the real part of the frequency-specific impedance.

[0102] Figures 6 to 8 This is a flowchart illustrating in detail the operation method of a battery diagnostic device according to an embodiment disclosed herein. According to the embodiment, Figures 6 to 8 The operations shown can be performed by Figure 1 The battery diagnostic device 100 is executed.

[0103] Reference Figure 6 In operation 610, controller 120 can calculate a first difference based on the difference between first information at a first frequency and first information at multiple frequencies different from the first frequency. For example, the first frequency could be the minimum frequency among the frequencies used to calculate the impedance. In another example, the first frequency could be the maximum frequency among the frequencies used to calculate the impedance. That is, the first frequency could be a reference frequency among the frequencies used to calculate the impedance.

[0104] In operation 620, controller 120 can diagnose whether the battery contains abnormal battery cells based on a first difference at multiple frequencies. For example, controller 120 can calculate the difference between the real part of the impedance at the first frequency and the real parts of the impedance at multiple frequencies, and diagnose whether abnormal battery cells are included based on the calculated difference.

[0105] According to the implementation, operations 610 and 620 may include... Figure 5 In operation 540.

[0106] Reference Figure 7 In operation 710, the controller 120 can calculate a first difference for each of the multiple battery cells included in the battery.

[0107] In operation 720, controller 120 can calculate the average of the first difference for each of the multiple battery cells.

[0108] In operation 730, controller 120 can also diagnose battery abnormalities based on the average of the first difference and the first difference of each of the plurality of battery cells.

[0109] Operations 710 to 730 may include Figure 5 In operation 540. For example, a battery may include multiple battery cells.

[0110] Reference Figure 8 In operation 810, controller 120 can calculate the deviation between the average value of the first difference and the first difference of each of the plurality of battery cells.

[0111] In operation 820, when the deviation is greater than or equal to a preset value, the controller 120 can diagnose that the battery contains abnormal battery cells.

[0112] According to one implementation, the controller 120 can calculate the deviation within a set frequency range for diagnostic purposes. For example, the set frequency range may include a range from 0.5 Hz to 50 Hz.

[0113] Figure 9This is a block diagram illustrating the hardware configuration of a computing system for performing an operation method of a battery diagnostic device according to an embodiment disclosed herein.

[0114] Reference Figure 9 The computing system 1000 according to the embodiments disclosed herein may include a microcontroller unit (MCU) 1010, a memory 1020, an input / output interface (I / F) 1030, and a communication I / F 1040.

[0115] MCU 1010 can be a processor that executes various programs stored in memory 1020 (e.g., pulse generation program, voltage extraction program, impedance calculation program, battery diagnostic program, etc.). These programs process various information, including battery voltage, battery impedance, and the presence or absence of abnormal battery cells, and perform other tasks. Figure 1 The battery diagnostic device shown in the diagram includes the aforementioned functions of the controller.

[0116] The memory 1020 can store various programs, such as pulse generation programs, voltage extraction programs, impedance calculation programs, battery diagnostic programs, etc. In addition, the memory 1020 can store various information, such as battery voltage, battery impedance, and the presence or absence of abnormal battery cells.

[0117] The memory 1020 can be provided in multiples as needed. The memory 1020 can be volatile or non-volatile. For the memory 1020 as volatile memory, random access memory (RAM), dynamic RAM (DRAM), static RAM (SRAM), etc., can be used. For the memory 1020 as non-volatile memory, read-only memory (ROM), programmable ROM (PROM), electrically rewritable ROM (EAROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), flash memory, etc., can be used. The examples of memory 1020 listed above are merely examples and are not limited to this.

[0118] The Input / Output I / F 1030 provides an interface for sending and receiving data by connecting input devices (not shown) such as a keyboard, mouse, touch panel, etc., and output devices such as a display (not shown) to the MCU 1010.

[0119] The communication I / F 1040, which is a component capable of sending and receiving various types of data from a server, can be any type of device capable of supporting wired or wireless communication. For example, a battery diagnostic device can use the communication I / F 1040 to send and receive various information from a separately provided external server, including information such as battery voltage, battery impedance, and the presence or absence of abnormal battery cells.

[0120] Therefore, the computer program according to the embodiments disclosed herein can be recorded in memory 1020 and processed by MCU 1010, thereby being implemented to, for example, execute... Figure 1 The modules for each function are shown in the image.

[0121] The above description is merely an illustration of the technical concept disclosed herein, and various modifications and changes can be made by those skilled in the art to which the embodiments disclosed herein pertain without departing from the basic characteristics of the embodiments disclosed herein.

[0122] Therefore, the embodiments disclosed herein are intended to describe, and not limit, the technical spirit of the embodiments disclosed herein, and the scope of the technical spirit disclosed herein is not limited by these embodiments. The scope of protection of the technical spirit disclosed herein should be interpreted by the following claims, and all technical spirit within the same scope should be understood to be included within the scope of this document.

[0123] [Explanation of reference numerals for key components in the attached diagram]

[0124] 100: Battery diagnostic device

[0125] 110: Pulse application unit

[0126] 120: Controller

[0127] 1000: Computing System

[0128] 1010: MCU

[0129] 1020: Memory

[0130] 1030: Input / Output I / F

[0131] 1040: Communication I / F

Claims

1. A battery diagnostic device, comprising: A pulse application unit is configured to apply a current pulse to the battery; as well as The controller is configured to: Obtain the first voltage corresponding to the current pulse; The frequency-specific impedance of the battery is calculated using Fourier transform based on the current pulse and the first voltage; as well as The presence of abnormal battery cells in the battery is diagnosed based on first information about the battery that is related to the frequency-specific impedance of the battery.

2. The battery diagnostic device according to claim 1, wherein, The pulse application unit is further configured to apply at least one of a charging current pulse and a discharging current pulse to the battery.

3. The battery diagnostic device according to claim 1, wherein, The pulse application unit is also configured to alternately apply at least two of the following signals to the battery: a charging current pulse, a rest current pulse, and a discharging current pulse.

4. The battery diagnostic device according to claim 1, wherein, The first information includes at least one of the following: the real part of the frequency-specific impedance, the imaginary part of the frequency-specific impedance, the amplitude of the frequency-specific impedance, or the phase of the frequency-specific impedance.

5. The battery diagnostic device according to claim 1, wherein, The controller is also configured to: The first difference is calculated based on the differences between the first information at a first frequency and the first information at multiple frequencies different from the first frequency; and The presence of abnormal battery cells in the battery is diagnosed based on the first difference at the plurality of frequencies.

6. The battery diagnostic device according to claim 5, wherein, The controller is also configured to: Calculate the first difference for each of the plurality of battery cells included in the battery; Calculate the average of the first difference for each of the plurality of battery cells; as well as The abnormality of the battery is diagnosed based on the average of the first difference and the first difference of each of the plurality of battery cells.

7. The battery diagnostic device according to claim 6, wherein, The controller is also configured to: Calculate the deviation between the average of the first differences and the first difference of each of the plurality of battery cells; and When the deviation is greater than or equal to a preset value, the battery is diagnosed to contain an abnormal battery cell.

8. The battery diagnostic device according to claim 7, wherein, The controller is also configured to calculate the deviation within a set frequency range.

9. The battery diagnostic device according to claim 5, wherein, The first frequency is the lowest frequency among the frequencies from which the impedance was calculated.

10. The battery diagnostic device according to claim 5, wherein, The first frequency is the highest frequency among the frequencies at which the impedance is calculated.

11. A method for operating a battery diagnostic device, the method comprising: Apply a current pulse to the battery; Obtain the first voltage corresponding to the current pulse; The frequency-specific impedance of the battery is calculated using Fourier transform based on the current pulse and the first voltage; as well as The presence of abnormal battery cells in the battery is diagnosed based on first information about the battery that is related to the frequency-specific impedance of the battery.

12. The operating method according to claim 11, wherein, Applying the current pulse to the battery includes applying at least one of a charging current pulse and a discharging current pulse to the battery.

13. The operating method according to claim 11, wherein, Applying the current pulse to the battery includes alternately applying at least two of the following signals: a charging current pulse, a rest current pulse, and a discharging current pulse to the battery.

14. The operating method according to claim 11, wherein, The first information includes at least one of the following: the real part of the frequency-specific impedance, the imaginary part of the frequency-specific impedance, the amplitude of the frequency-specific impedance, or the phase of the frequency-specific impedance.

15. The operating method according to claim 11, wherein, Diagnosing whether the battery contains the abnormal battery cell based on first information about the battery related to the frequency-specific impedance of the battery includes: The first difference is calculated based on the differences between the first information at a first frequency and the first information at multiple frequencies different from the first frequency; and The presence of abnormal battery cells in the battery is diagnosed based on the first difference at the plurality of frequencies.

16. The operating method according to claim 15, wherein, Diagnosing whether the battery contains the abnormal battery cell based on first information about the battery related to the frequency-specific impedance of the battery includes: Calculate the first difference for each of the plurality of battery cells included in the battery; Calculate the average of the first difference for each of the plurality of battery cells; and The abnormality of the battery is diagnosed based on the average of the first difference and the first difference of each of the plurality of battery cells.

17. The operating method according to claim 16, wherein, Diagnosing battery abnormalities based on the average of the first differences and the first difference of each of the plurality of battery cells includes: Calculate the deviation between the average of the first differences and the first difference of each of the plurality of battery cells; and When the deviation is greater than or equal to a preset value, the battery is diagnosed to contain an abnormal battery cell.

18. The operating method according to claim 17, wherein, Calculating the deviation between the average of the first difference and the first difference of each of the plurality of battery cells includes calculating the deviation within a set frequency range.

19. The operating method according to claim 15, wherein, The first frequency is the highest frequency among the frequencies at which the impedance is calculated.

20. The operating method according to claim 15, wherein, The first frequency is the highest frequency among the frequencies at which the impedance is calculated.

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