Battery diagnostic device and its operating method

Abstract

A battery diagnostic device according to one embodiment disclosed herein may include a sensor for acquiring voltage data for each of the battery cells; and a processor for calculating a voltage change (dV), which is the difference between the voltage values ​​at any two points in time for each of the battery cells, based on the voltage data; calculating a cumulative change based on the voltage change; and diagnosing whether or not there is an abnormality in the battery cells based on the cumulative change.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2023 - 0095638, filed on July 21, 2023, and all the contents disclosed in the literature of the Korean patent application are included as part of this specification.

[0002] The embodiments disclosed in this document relate to a battery diagnostic device and an operation method thereof.

Background Art

[0003] Recently, research and development on secondary batteries have been actively conducted. Here, a secondary battery is a battery that can be charged and discharged, and includes all conventional Ni / Cd batteries, Ni / MH batteries, etc., and recent lithium - ion batteries. Among secondary batteries, lithium - ion batteries have the advantage of having a much higher energy density compared to conventional Ni / Cd batteries, Ni / MH batteries, etc. Also, lithium - ion batteries can be manufactured in a small size and light weight, are used as power sources for mobile devices, and recently, their usage range has been expanded to power sources for electric vehicles and has attracted attention as a next - generation energy storage medium.

[0004] As the industrial fields utilizing batteries expand, battery management systems (BMS: Battery Management System) for diagnosing battery safety are also developing. BMS can diagnose the performance of batteries by utilizing various diagnostic algorithms and can perform appropriate control according to the state of the battery. BMS can diagnose the presence or absence of abnormal battery cells. Here, an abnormality may include all causes that may cause ignition due to damage or aging of the battery itself. In particular, the use of electronic products equipped with abnormal batteries due to lithium precipitation may cause a fire, so there is a need to detect abnormal battery cells early.

Summary of the Invention

[0005] During the post-discharge rest period, abnormal battery cells may exhibit different voltage behavior than normal battery cells. This allows for the detection of abnormal battery cells by checking the voltage difference obtained via sensing signals for each individual battery cell.

[0006] However, sensor signals are not only weak in strength and have irregular signal cycles, but they can also contain various types of noise. Because there is a high degree of uncertainty in the sensor signals themselves, if we rely solely on the sensor signals to determine whether or not a battery cell is abnormal, there is a problem in that the accuracy of selecting abnormal battery cells decreases.

[0007] The technical problems of the embodiments disclosed herein are not limited to those mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0008] A battery diagnostic device according to one embodiment disclosed herein may include a sensor for acquiring voltage data for each of the battery cells; and a processor for calculating a voltage change (dV), which is the difference between the voltage values ​​at any two points in time for each of the battery cells, based on the voltage data; calculating a cumulative change based on the voltage change; and diagnosing whether or not there is an abnormality in the battery cells based on the cumulative change.

[0009] In one embodiment, the processor can calculate a Z-score, which is a standardized value of the voltage change amount based on the mean and standard deviation of the voltage change amount for the battery cell, and calculate the cumulative change amount based on the Z-score.

[0010] In one embodiment, the mean and standard deviation are the mean and standard deviation of the voltage change for each battery unit, including some of the battery cells out of all battery cells, and the processor can calculate the Z value for each battery unit, calculate the cumulative change amount based on the Z value, and diagnose whether or not there is an abnormality in the battery unit based on the cumulative change amount.

[0011] In one embodiment, the two arbitrary time points may be any two time points within the post-discharge rest period.

[0012] In one embodiment, the processor can diagnose a battery cell showing an increasing trend in the cumulative change amount as an abnormal battery cell.

[0013] In one embodiment, the battery diagnostic device may further include a communication circuit for transmitting the diagnostic results to a user terminal.

[0014] The operation method of a battery diagnostic device according to one embodiment disclosed herein may include: an operation to acquire voltage data for each of the battery cells; an operation to calculate a voltage change (dV), which is the difference between the voltage values ​​at any two points in time for each of the battery cells, based on the voltage data; an operation to calculate a cumulative change based on the voltage change; and an operation to diagnose whether or not there is an abnormality in the battery cells based on the cumulative change.

[0015] In one embodiment, the operation method may further include an operation to calculate a Z-score, which is a standardized value of the voltage change amount based on the mean and standard deviation of the voltage change amount for the battery cell, and the operation to calculate the cumulative change amount can calculate the cumulative change amount based on the Z-score.

[0016] In one embodiment, the mean and standard deviation are the mean and standard deviation of the voltage change for each battery unit, including some of the battery cells out of all battery cells, the operation to calculate the Z value calculates the Z value for each battery unit, and the diagnostic operation can diagnose whether or not there is an abnormality in the battery unit based on the cumulative change.

[0017] In one embodiment, the two arbitrary time points may be any two time points within the post-discharge rest period.

[0018] In one embodiment, the diagnostic operation can diagnose a battery unit showing an increasing trend in the cumulative change amount as an abnormal battery unit.

[0019] In one embodiment, the operation method may further include an operation to transmit the diagnostic result to the user terminal. [Effects of the Invention]

[0020] The battery diagnostic device and its operating method according to various embodiments disclosed herein can detect abnormal battery cells based on the trend of the cumulative change in voltage generated by abnormal battery cells by calculating the cumulative change in voltage for each battery cell.

[0021] The battery diagnostic device and its operating method according to various embodiments disclosed herein can reduce errors that may occur between battery modules by converting the voltage change amount to the battery cell into a Z-score.

[0022] The effects of the battery diagnostic device and its operating method disclosed herein are not limited to those mentioned above, and any other effects not mentioned herein can be clearly understood by those skilled in the art through the disclosure herein. [Brief explanation of the drawing]

[0023] [Figure 1]Shows a battery diagnostic device according to an embodiment disclosed in this document. [Figure 2] Shows a battery diagnostic device according to an embodiment disclosed in this document. [Figure 3] It is a block diagram of a battery diagnostic device according to an embodiment disclosed in this document. [Figure 4] Illustrates a graph for voltage data of battery cells according to an embodiment disclosed in this document. [Figure 5] Illustrates a graph for the cumulative change amount of battery cells included in different vehicles according to an embodiment disclosed in this document. [Figure 6] It is a flowchart showing an operation method of a battery diagnostic device for diagnosing abnormal battery cells according to an embodiment disclosed in this document. [Figure 7] It is a flowchart showing an operation method of a battery diagnostic device for diagnosing abnormal battery units according to an embodiment disclosed in this document.

[0024] In connection with the description of the drawings, the same or similar reference numerals can be used for the same or similar components.

Embodiments for Carrying Out the Invention

[0025] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include various modifications, equivalents, and / or alternatives of the embodiments of the present invention.

[0026] The embodiments and terminology used herein are not intended to limit the technical features described herein to any particular embodiment, but should be understood to include various modifications, equivalents, or substitutions of such embodiments. In connection with the description of the drawings, similar or related reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of such items unless otherwise indicated to be clearly different in the context.

[0027] In this document, each of the phrases “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B or C,” “at least one of A, B and C,” and “at least one of A, B, or C” may include any one of the items listed together with the applicable phrase, or any possible combination thereof. Terms such as “first,” “second,” “primary,” “second,” “A,” “B,” “(a),” or “(b)” may be used simply to distinguish one component from other components and, unless otherwise stated, do not limit the component in any other way (e.g., importance or order).

[0028] In this document, when a component (e.g., the first) is referred to as being "coupled," "joined," or "connected" to another component (e.g., the second) with or without such terms, it means that the first component may be connected to the other component directly (e.g., by wire or wireless) or indirectly (e.g., via the third component).

[0029] The methods according to the various embodiments disclosed herein may be provided in a computer program product. The computer program product may be traded as a commodity between sellers and buyers. The computer program product may be distributed in the form of a device-readable recording medium (e.g., compact disc read-only memory, CD-ROM) or online (e.g., by download or upload) via an application store or directly between two user devices. In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated on a device-readable recording medium such as the memory of a manufacturer's server, an application store server, or an intermediary server.

[0030] According to the embodiments disclosed herein, each of the aforementioned components (e.g., a module or a program) may include one or more individuals, some of which may be separated and arranged in other components. According to the embodiments disclosed herein, one or more of the aforementioned components or operations may be omitted, or one or more other components or operations may be added. Alternatively or additionally, multiple components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the multiple components identical or similar to those performed by the components prior to the integration. According to the embodiments disclosed herein, operations performed by a module, program, or other component may be performed sequentially, in parallel, repeatedly, or heuristically, or one or more of the operations may be performed in a different order, omitted, or one or more other operations may be added.

[0031] Figure 1 shows a battery diagnostic device 10 according to one embodiment disclosed in this document.

[0032] Referring to Figure 1, the battery diagnostic device 10 may be a BMS capable of diagnosing and controlling battery cells. In one embodiment, the battery diagnostic device 10 may include a battery pack BMS, a slave BMS, or a combination thereof. The battery diagnostic device 10 may be a BMS that senses the voltage, current, and temperature of the battery cells to control and diagnose the battery cells.

[0033] In other embodiments, the battery diagnostic device 10 may be a server or a charger. The battery diagnostic device 10 may be included in the server or charger. The operations performed by the battery diagnostic device 10 may be performed by the server or charger.

[0034] The battery diagnostic device 10 can acquire voltage data for battery units 121, 122, and 123 included in the electronic device 12. Here, each of the battery units 121, 122, and 123 may be a battery cell, a battery module, a battery pack, or a battery rack. The voltage data may be the voltage values ​​for battery units 121, 122, and 123 over a specified time interval. In one embodiment, the battery diagnostic device 10 can acquire the voltage values ​​of each of the battery units 121, 122, and 123 included in the electronic device 12 via a sensor. In one embodiment, the battery diagnostic device 10 can acquire the voltage values ​​of each of the battery units 121, 122, and 123 included in the electronic device 12 via a communication circuit. Here, the sensor and communication circuit may be included in the battery diagnostic device 10, and details regarding the sensor and communication circuit will be described later.

[0035] The battery diagnostic device 10 can calculate the voltage change (dV) for each of the battery units 121, 122, and 123 based on the voltage data. Here, the voltage change can be calculated based on the difference between the voltage values ​​at at least two points in time included in the voltage data for each of the battery units 121, 122, and 123.

[0036] The battery diagnostic device 10 can calculate the cumulative change amount by accumulating the voltage changes for each battery cell.

[0037] The battery diagnostic device 10 can diagnose whether or not there is an abnormality in each of the battery units 121, 122, and 123 based on the cumulative change amount.

[0038] The battery diagnostic device 10 can transmit diagnostic results to the user terminal 14. The battery diagnostic device 10 can transmit diagnostic results to the user terminal 14 via a communication circuit. Here, the user terminal 14 may be a mobile device or PC capable of checking the diagnostic results.

[0039] The battery diagnostic device 10 may be connected to the electronic device 12 and the user terminal 14 by wire and / or wirelessly.

[0040] In one embodiment, the connection between the battery diagnostic device 10 and the electronic device 12 may be a wired and / or wireless network communication connection. In one embodiment, the wired network may be based on LAN (local area network) communication or power line communication. In one embodiment, the wireless network may be based on a short-range communication network (e.g., Bluetooth®, WiFi (wireless fidelity), or IrDA (infrared data association)) or a long-range communication network (cellular network, 4G network, 5G network).

[0041] In one embodiment, the connection between the battery diagnostic device 10 and the electronic device 12 may be a device-to-device communication method (for example, a bus, GPIO (general purpose input and output), SPI (serial peripheral interface), or MIPI (mobile industry processor interface)).

[0042] In one embodiment, the connection between the battery diagnostic device 10 and the user terminal 14 may be a wired and / or wireless network communication connection.

[0043] In one embodiment, the electronic device 12 may be a mobile device (e.g., a mobile phone, laptop computer, smartphone, smartpad), an electric vehicle (e.g., an EV (electric vehicle), a HEV (hybrid EV), a PHEV (plug-in HEV), a FCEV (fuel cell EV)), an energy storage system (ESS), or a battery swapping system (BSS).

[0044] In one embodiment, the electronic device 12 may include one or more battery units 121, 122, 123, where each of the battery units 121, 122, 123 may be a battery cell, a battery module, a battery pack, or a battery rack.

[0045] In one embodiment, the user terminal 14 may be a mobile device (e.g., a mobile phone, laptop computer, smartphone, smartpad) or a PC (personal computer).

[0046] In the following explanation, we will assume that each battery cell abnormality is due to lithium deposition. However, this is merely for the sake of explanation, and battery cell abnormalities may include all abnormalities caused by internal short circuits that could lead to fire, as well as overcharging, etc.

[0047] Figure 2 shows a battery diagnostic device 10 according to one embodiment disclosed in this document.

[0048] Referring to Figure 2, the battery diagnostic device 10 may be a battery pack BMS that manages multiple slave BMSs 111, 112, and 113. The battery diagnostic device 10 can acquire voltage data for battery units 121, 122, and 123 from each of the slave BMSs 111, 112, and 113, and can use the acquired voltage data to diagnose whether there are any abnormalities in the battery cells contained in the battery pack. Here, the slave BMS can perform diagnosis and control of the battery units as a subordinate system of the battery pack BMS. For example, the first slave BMS 111 can sense the voltage, current, and temperature of the battery cells contained in the first battery unit 121, and can control and diagnose each of the battery cells contained in the first battery unit 121. Each of the battery units 121, 122, and 123 may be a battery cell, a battery module, a battery pack, a battery rack, or a battery group. A battery group can refer to a collection of battery cells that can be sensed by the slave BMS. For example, the first slave BMS 111 can perform diagnostics and control of the first battery unit 121, and the first battery unit 121 may be referred to as a battery group.

[0049] The battery diagnostic device 10 can acquire voltage data for each of the battery units 121, 122, and 123 from each of the multiple slave BMSs 111, 112, and 113. Here, the voltage data may be the voltage values ​​for the battery units 121, 122, and 123 over a specified time interval. For example, the battery diagnostic device 10 can acquire the voltage value of the first battery unit 121 via the first slave BMS 111.

[0050] The battery diagnostic device 10 can calculate the voltage change for each of the battery units 121, 122, and 123 based on the voltage data.

[0051] The battery diagnostic device 10 can convert the voltage change amounts for each of the battery units 121, 122, and 123 into Z values. Here, the Z values ​​may be values ​​that standardize each voltage change amount based on the average value and standard deviation of the voltage change amounts of all battery cells. In one embodiment, the battery diagnostic device 10 can calculate the Z values ​​using the average and standard deviation of the voltage change amounts for each battery unit. For example, the battery diagnostic device 10 can calculate the Z values ​​for each of the battery cells included in the first battery unit 121 based on the average and standard deviation of the voltage change amounts for the battery cells included in the first battery unit 121. The method for calculating the Z values ​​will be described later in Figure 3.

[0052] The battery diagnostic device 10 can calculate the cumulative change amount by accumulating the Z values ​​for each of the battery units 121, 122, and 123.

[0053] The battery diagnostic device 10 can diagnose whether or not there is an abnormality in each of the battery units 121, 122, and 123 based on the cumulative change amount.

[0054] The battery diagnostic device 10 can transmit diagnostic results to the user terminal 14. The battery diagnostic device 10 can transmit diagnostic results to the user terminal 14 via a communication circuit. Here, the user terminal 14 may be a mobile device or PC capable of checking the diagnostic results.

[0055] Figure 3 is a block diagram of a battery diagnostic device 10 according to one embodiment disclosed in this document.

[0056] Referring to Figure 3, the battery diagnostic device 10 may include a sensor 100, a memory 102, a processor 104, a communication circuit 106, or a combination thereof.

[0057] Sensor 100 can acquire values ​​related to the state of the battery units 121, 122, and 123 of the electronic device 12. In one embodiment, the state values ​​may represent one or more values ​​for the voltage, current, resistance, state of charge (SOC), state of health (SOH), or temperature of the battery units 121, 122, and 123, or a combination thereof. Sensor 100 can acquire voltage data for the battery units 121, 122, and 123 of the electronic device 12. Sensor 100 can acquire voltage data for the battery units 121, 122, and 123 for each specified cycle. Hereinafter, the state values ​​may be referred to as "state values".

[0058] In one embodiment, the sensor 100 may not be included in the battery diagnostic device 10 if the operation performed by the battery diagnostic device 10 is performed by a server or charger. If the battery diagnostic device 10 does not include the sensor 100, the battery diagnostic device 10 can obtain status values ​​for battery units 121, 122, and 123 via the communication circuit 106.

[0059] Memory 102 can store data used by at least one component of the battery diagnostic device 10 (e.g., processor 104). For example, the data may include software (or instructions related thereto), input data, or output data. In one embodiment, the instructions can cause the battery diagnostic device 10 to perform the operations defined by the instructions at runtime by the processor 104. In one embodiment, memory 102 may include volatile memory and / or non-volatile memory. In one embodiment, memory 102 may include one or more software programs.

[0060] The processor 104 can execute software (e.g., a battery diagnostic algorithm) to control at least one other component (e.g., a hardware or software component) of the battery diagnostic device 10 connected to the processor 104, and can perform various data processing or calculations.

[0061] The processor 104 can calculate the voltage change (dV) for each battery cell. The processor 104 can calculate the voltage change for each battery cell based on the voltage data for each battery cell. The processor 104 can calculate the voltage change based on the voltage data in the post-discharge rest period. The processor 104 can calculate the voltage change based on the voltage data in a specified time interval within the rest period. Here, the voltage change may be calculated based on the difference between voltage values ​​at at least two points in time included in the voltage data. The post-discharge rest period may be a time interval after a certain amount of time has passed since the vehicle stopped starting. For example, for each battery cell included in the first battery unit 121, the processor 104 can calculate the voltage change for each battery cell based on the difference between the voltage value corresponding to 1200 seconds and the voltage value corresponding to 7200 seconds within the post-discharge rest period.

[0062] The processor 104 can calculate the voltage change for each battery cell at each specified cycle. The processor 104 can calculate the voltage change for each battery cell during the post-discharge rest period at each specified cycle.

[0063] The processor 104 can calculate a Z-score based on the voltage change. The processor 104 can convert the voltage change for each battery cell into a Z-score. The processor 104 can calculate a standardized Z-score for each battery cell based on the voltage change for each battery cell. The processor 104 can convert the voltage change for each battery cell into a Z-score based on the mean and standard deviation of the voltage change for each battery cell. Here, the Z-score may be a standardized value for each voltage change based on the mean and standard deviation of the voltage changes for all battery cells. The Z-score can be expressed by mathematical formula 1.

[0064] [Mathematics 1] TIFF2026522672000002.tif3469 Here, x may be the voltage change for each battery cell, u may be the average of the voltage changes, and σ may be the standard deviation of the voltage changes.

[0065] In one embodiment, the processor 104 can calculate Z values ​​for each battery unit. The processor 104 can calculate Z values ​​for each battery cell included in the same battery unit. The processor 104 can convert the voltage change for each battery cell in each battery unit into a Z value. The processor 104 can calculate Z values ​​for each battery unit based on the voltage change for each battery unit, which includes at least some of the battery cells of all battery cells. The processor 104 can convert the voltage change for each battery cell included in the same battery unit into a Z value based on the mean and standard deviation of the voltage change for each battery unit. For example, the processor 104 can convert the voltage data for each battery cell included in the first battery unit 121 into a Z value based on the mean voltage and standard deviation of the battery cells included in the first battery unit 121. Here, the Z value may be a value obtained by standardizing each voltage change based on the mean and standard deviation of the voltage changes of each of the battery units 121, 122, and 123. The processor 104 can reduce errors caused by differences in SOC between battery modules by converting voltage data into Z values ​​and standardizing the voltage data for all battery cells.

[0066] The processor 104 can calculate the cumulative change by accumulating the voltage changes for each battery cell. The processor 104 can calculate the cumulative change by accumulating the voltage changes obtained for each battery cell according to a specified cycle.

[0067] In one embodiment, the processor 104 can calculate the cumulative change amount by accumulating the Z value for each battery cell. The processor 104 can calculate the cumulative change amount by accumulating the Z value based on the voltage change amount obtained for each battery cell according to a specified cycle.

[0068] In one embodiment, the processor 104 can calculate the cumulative change for each battery unit. The processor 104 can calculate the cumulative change based on the converted Z value for each battery unit. The processor 104 can calculate the cumulative change based on the converted Z value according to the specified cycle for each battery unit.

[0069] The processor 104 can diagnose whether a battery cell is abnormal based on the cumulative change. The processor 104 can diagnose whether a battery cell is abnormal based on whether the cumulative change tends to increase. The processor 104 can diagnose a battery cell whose cumulative change tends to increase as an abnormal battery cell. The processor 104 can diagnose a battery cell whose cumulative change exceeds a critical value as an abnormal battery cell. Here, the critical value may be the average or median of the cumulative change for all battery cells.

[0070] In one embodiment, the processor 104 can diagnose whether a battery unit is abnormal based on the cumulative change. The processor 104 can detect abnormal battery units based on the cumulative change. The processor 104 can diagnose whether a battery unit is abnormal depending on whether the cumulative change tends to increase. The processor 104 can diagnose a battery unit in which the cumulative change tends to increase as an abnormal battery unit. The processor 104 can diagnose a battery unit in which the cumulative change exceeds a critical value as an abnormal battery unit. Here, an abnormal battery unit may be a battery module containing one or more abnormal battery cells. The critical value may be the average or median value of the cumulative change for the battery cells included in the battery unit.

[0071] The processor 104 described above may include a central processing unit, an application processor, a graphics processing unit, a neural processing unit (NPU), an image signal processor, a sensor processor, or a communication processor.

[0072] The processor 104 can execute software to control at least one other component (e.g., hardware or software component) of the battery diagnostic device 10 connected to the processor 104, and can perform various data processing or calculations.

[0073] The communication circuit 106 establishes a wired communication channel and / or a wireless communication channel between the battery diagnostic device 10 and the electronic device 12 and / or the user terminal 14, and can send and receive data with the electronic device 12 and / or the user terminal 14 via the established communication channel.

[0074] In one embodiment, if the battery diagnostic device 10 is a device included in a server or charger, the communication circuit 106 can receive status values ​​for the battery units 121, 122, and 123 via wired or wireless connection from the electronic device 12 or sensor 100.

[0075] In one embodiment, the communication circuit 106 can transmit the diagnostic results performed by the processor 104 to the user terminal 14.

[0076] Depending on the embodiment, the battery diagnostic device 10 shown in Figure 3 may further include at least one component other than the components shown in Figure 3 (for example, a display, an input device, or an output device).

[0077] Figure 4 illustrates graph 40 for voltage data of a battery cell according to one embodiment disclosed in this document.

[0078] Referring to Figure 4, Graph 40 shows the voltage values ​​for the battery cell during a specified time interval 400. Here, the specified time interval 400 may be all or part of the post-discharge rest interval. Referring to Graph 40, the post-discharge rest interval may be a time interval between 1200 seconds and 9000 seconds, and the specified time interval 400 may be a time interval between 1200 seconds and 7200 seconds.

[0079] The voltage data may be the voltage values ​​for the battery cells during a specified time interval within the post-discharge rest period. For example, the battery diagnostic device 10 can calculate the voltage change for each battery cell based on the difference between the voltage value at 1200 seconds and the voltage value at 7200 seconds.

[0080] Figure 5 illustrates graphs 50, 52, and 54 showing the cumulative change in one embodiment disclosed in this document.

[0081] Referring to Figure 5, the first graph 50 shows abnormal battery units, the second graph 52 shows normal battery units, and the third graph 54 shows battery units due to other causes. Here, "other causes" may include causes remaining after excluding those that cause fire. For example, "other causes" may be quality defects that occurred during the battery cell manufacturing process.

[0082] Referring to Graph 50, we can see that the cumulative change tends to increase as the cycle progresses. Here, this increasing trend may include cases where the cumulative change decreases in some cycles, but the overall cumulative change increases compared to the initial cycle.

[0083] Referring to Graphs 52 and 54, we can see that the cumulative change tends to decrease as the cycle progresses. Here, the decreasing trend may include cases where the cumulative change increased in some cycles but decreased compared to the initial cycle.

[0084] Referring to graphs 50, 52, and 54, the battery diagnostic device 10 can diagnose a battery cell as abnormal if the cumulative change amount over cycles tends to increase.

[0085] Figure 6 is a flowchart showing the operation method of a battery diagnostic device 10 for diagnosing abnormal battery cells according to one embodiment disclosed in this document.

[0086] Referring to Figure 6, in operation 600, the sensor 100 can acquire voltage data of the battery units 121, 122, and 123 of the electronic device 12. The sensor 100 can acquire voltage data of the battery units 121, 122, and 123 at specified cycle intervals. In one embodiment, the sensor 100 may not be included in the battery diagnostic device 10 if the operation performed by the battery diagnostic device 10 is performed by a server or charger. If the sensor 100 is not included in the battery diagnostic device 10, the battery diagnostic device 10 can acquire status values ​​for the battery units 121, 122, and 123 via the communication circuit 106.

[0087] In operation 602, the processor 104 can calculate the voltage change (dV) for each battery cell. The processor 104 can calculate the voltage change for each battery cell based on the voltage data for each battery cell. The processor 104 can calculate the voltage change based on the voltage data in the post-discharge rest period. The processor 104 can calculate the voltage change based on the voltage data in a specified time interval within the rest period.

[0088] The processor 104 can calculate the voltage change for each battery cell at each specified cycle. The processor 104 can calculate the voltage change for each battery cell during the post-discharge rest period at each specified cycle.

[0089] In operation 604, the processor 104 can calculate the cumulative change by accumulating the voltage changes for each battery cell. The processor 104 can calculate the cumulative change by accumulating the voltage changes obtained for each battery cell according to a specified cycle.

[0090] In operation 606, the processor 104 can diagnose whether there is an abnormality in the battery cell based on the cumulative change. The processor 104 can diagnose whether there is an abnormality in the battery cell based on whether the cumulative change tends to increase.

[0091] In operation 608, the processor 104 can diagnose a battery cell whose cumulative change tends to increase as an abnormal battery cell. The processor 104 can also diagnose a battery cell whose cumulative change exceeds a critical value as an abnormal battery cell.

[0092] In operation 610, the processor 104 can diagnose a battery cell whose cumulative change tends to decrease as a normal battery cell. The processor 104 can diagnose a battery cell whose cumulative change is below a critical value as a normal battery cell.

[0093] Figure 7 is a flowchart showing the operation method of a battery diagnostic device 10 for diagnosing an abnormal battery unit according to one embodiment disclosed in this document.

[0094] Referring to Figure 7, in operation 700, the sensor 100 can acquire voltage data of the battery units 121, 122, and 123 of the electronic device 12. The sensor 100 can acquire voltage data of the battery units 121, 122, and 123 at specified cycle intervals. In one embodiment, the sensor 100 may not be included in the battery diagnostic device 10 if the operation performed by the battery diagnostic device 10 is performed by a server or charger. If the sensor 100 is not included in the battery diagnostic device 10, the battery diagnostic device 10 can acquire status values ​​for the battery units 121, 122, and 123 via the communication circuit 106.

[0095] In operation 702, the processor 104 can calculate the voltage change (dV) for each battery cell. The processor 104 can calculate the voltage change for each battery cell based on the voltage data for each battery cell. The processor 104 can calculate the voltage change based on the voltage data in the post-discharge rest period. The processor 104 can calculate the voltage change based on the voltage data in a specified time interval within the rest period.

[0096] The processor 104 can calculate the voltage change for each battery cell at each specified cycle. The processor 104 can calculate the voltage change for each battery cell during the post-discharge rest period at each specified cycle.

[0097] In operation 704, the processor 104 can calculate the Z-score based on the voltage change. The processor 104 can convert the voltage change for each battery cell into a Z-score.

[0098] In one embodiment, the processor 104 can convert the voltage change for each battery cell in each battery unit into a Z value. The processor 104 can calculate a Z value for each battery cell included in the same battery unit.

[0099] In operation 706, the processor 104 can calculate the cumulative change by accumulating the voltage changes for each battery cell. The processor 104 can calculate the cumulative change by accumulating the voltage changes obtained for each battery cell according to a specified cycle.

[0100] In one embodiment, the processor 104 can calculate the cumulative change amount by accumulating the Z value for each battery cell. The processor 104 can calculate the cumulative change amount by accumulating the Z value based on the voltage change amount obtained for each battery cell according to a specified cycle.

[0101] In one embodiment, the processor 104 can calculate the cumulative change for each battery unit. The processor 104 can calculate the cumulative change based on the converted Z value for each battery unit. The processor 104 can calculate the cumulative change based on the converted Z value according to the specified cycle for each battery unit.

[0102] In operation 708, the processor 104 can diagnose whether there is an abnormality in the battery unit based on the cumulative change. The processor 104 can detect an abnormal battery unit based on the cumulative change. The processor 104 can diagnose whether there is an abnormality in the battery unit depending on whether the cumulative change tends to increase or not.

[0103] In operation 710, the processor 104 can diagnose a battery unit whose cumulative change tends to increase as an abnormal battery unit. The processor 104 can diagnose a battery unit whose cumulative change exceeds a critical value as an abnormal battery unit.

[0104] In operation 712, the processor 104 can diagnose a battery unit whose cumulative change tends to decrease as a normal battery unit. The processor 104 can diagnose a battery unit whose cumulative change is below a critical value as a normal battery unit.

[0105] The operations performed by the battery diagnostic device 10 described above were explained assuming they were performed on the vehicle's BMS, but these operations may also be performed on an external server and charger.

[0106] The terms "contains," "constitutes," or "possesses," as used above, mean that the component in question may be present, unless otherwise stated, and should be interpreted as including other components rather than excluding them. All terms, including technical and scientific terms, have the same meaning as those generally understood by a person of ordinary skill in the art to which the embodiments disclosed herein belong, unless otherwise defined. Commonly used terms, such as those defined in dictionaries, should be interpreted to be consistent with their meaning in the context of the relevant technology and not as ideal or overly formal unless explicitly defined herein.

[0107] The above description is merely illustrative of the technical concept disclosed herein, and a person with ordinary skill in the art to which the embodiments disclosed herein belong can make various modifications and variations, provided that they do not deviate from the essential characteristics of the embodiments disclosed herein. Therefore, the embodiments disclosed herein are for illustrative purposes only, not to limit the technical concept of the embodiments disclosed herein, and the scope of the technical concept disclosed herein is not limited by such embodiments. The scope of protection of the technical concept disclosed herein shall be interpreted in accordance with the following claims, and all technical concepts within an equivalent scope shall be interpreted as being included in the scope of rights of this document.

Claims

1. A sensor that acquires voltage data for each battery cell, Based on the voltage data, the voltage change (dV), which is the difference between the voltage values ​​at any two points in time for each of the battery cells, is calculated. Based on the aforementioned voltage change, the cumulative change is calculated, A processor that diagnoses whether or not there is an abnormality in the battery cell based on the cumulative change amount, Battery diagnostic device.

2. The aforementioned processor, Based on the average and standard deviation of the voltage change for the battery cell, the Z-score (Z-score) is calculated by standardizing the voltage change. The cumulative change is calculated based on the Z value. The battery diagnostic device according to claim 1.

3. The aforementioned mean and standard deviation are the mean and standard deviation of the voltage change for each battery unit, including at least some of the battery cells of all battery cells. The aforementioned processor, The Z value is calculated for each of the aforementioned battery units. Based on the Z value, the cumulative change is calculated, Based on the cumulative change amount, the presence or absence of abnormality in the battery unit is diagnosed. The battery diagnostic device according to claim 2.

4. The aforementioned two arbitrary time points are any two time points within the post-discharge rest period. A battery diagnostic device according to any one of claims 1 to 3.

5. The aforementioned processor, A battery cell showing an increasing trend in the cumulative change amount is diagnosed as an abnormal battery cell. A battery diagnostic device according to any one of claims 1 to 3.

6. The system further includes a communication circuit for transmitting diagnostic results to the user's terminal. A battery diagnostic device according to any one of claims 1 to 3.

7. The operation of acquiring voltage data for each battery cell, The operation of calculating the voltage change (dV), which is the difference between the voltage values ​​of each of the battery cells at any two time points, based on the voltage data, The operation of calculating the cumulative change amount based on the aforementioned voltage change amount, An operation to diagnose whether there is an abnormality in the battery cell based on the cumulative change amount, including, How to operate the battery diagnostic device.

8. The process further includes calculating a Z-score (Z-score) obtained by standardizing the voltage change based on the average and standard deviation of the voltage change for the battery cell, The operation for calculating the cumulative change is as follows: The cumulative change is calculated based on the Z value. The operating method according to claim 7.

9. The aforementioned mean and standard deviation are the mean and standard deviation of the voltage change for each battery unit, including at least some of the battery cells of all battery cells. The operation for calculating the Z value is as follows: The Z value is calculated for each of the aforementioned battery units. The diagnostic actions described above are: Based on the cumulative change amount, the presence or absence of abnormality in the battery unit is diagnosed. The operating method according to claim 8.

10. The aforementioned two arbitrary time points are any two time points within the post-discharge rest period. The operating method according to any one of claims 7 to 9.

11. The diagnostic actions described above are: A battery unit showing an increasing trend in the cumulative change amount is diagnosed as an abnormal battery unit. The operating method according to any one of claims 7 to 9.

12. This further includes the operation of transmitting the diagnostic results to the user's terminal. The operating method according to any one of claims 7 to 9.

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