Battery management device and battery management method

Abstract

A battery management apparatus disclosed herein includes a communication unit configured to receive battery data of a battery cell, and a control unit configured to generate a discharge capacity change rate data based on the battery data, smooth the voltage data and the discharge capacity change rate data to obtain voltage smoothed data and discharge capacity smoothed data, and determine that the battery cell is defective based on the voltage smoothed data and the discharge capacity smoothed data satisfying a defect determination condition.

Description

Technical Field

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2023-0155641, filed on November 10, 2023, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The embodiments disclosed herein relate to battery management devices and battery management methods. Background Technology

[0005] Recently, research and development of rechargeable batteries have been actively pursued. In this paper, 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, making them already used as power sources for mobile devices. Moreover, as their applications expand to power electric vehicles, lithium-ion batteries are attracting attention as a next-generation energy storage medium.

[0006] When battery cells with assembly defects are present in a battery, they may overheat or catch fire during charging / discharging, posing a safety risk. Therefore, algorithms for detecting battery cells with assembly defects have been researched. Typically, to detect battery cells with assembly defects, raw data is used without smoothing, resulting in sporadic profiles that make it difficult to detect defective cells. Summary of the Invention

[0007] Technical issues

[0008] According to the embodiments disclosed herein, a battery management apparatus and method are provided, wherein exponential smoothing is applied to raw battery data to detect defective battery cells.

[0009] 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.

[0010] Technical solution

[0011] The battery management device according to an embodiment includes: a communication unit configured to receive battery data including voltage data of individual battery cells; and a control unit configured to generate discharge capacity change rate data based on the battery data, smooth the voltage data and discharge capacity change rate data to obtain voltage smoothed data and discharge capacity smoothed data, and determine that the individual battery cells are defective based on the voltage smoothed data and discharge capacity smoothed data satisfying defect determination conditions.

[0012] The controller can also be configured to perform exponential smoothing on voltage data and discharge capacity change rate data based on a smoothing coefficient applied to the exponential smoothing.

[0013] The controller can also be configured to obtain the predicted value by performing a weighted average of past predicted values ​​and past observations to exponentially smooth the voltage data and discharge capacity change rate data.

[0014] The controller can also be configured to determine that a battery cell is defective based on both voltage smoothing data and discharge capacity smoothing data meeting defect determination conditions within a preset time period.

[0015] The controller can also be configured to determine whether the voltage smoothing data and discharge capacity smoothing data meet the defect determination conditions based on the voltage smoothing data being less than the average voltage of multiple battery cells over a preset unit time and the discharge capacity smoothing data being greater than the rate of change of discharge capacity of multiple battery cells over that unit time.

[0016] The controller can also be configured to determine whether the voltage smoothing data and discharge capacity smoothing data meet the defect determination conditions based on the number of times the voltage smoothing data is less than the average voltage and the number of times the discharge capacity smoothing data exceeds the discharge capacity change rate within a certain period of time being greater than or equal to a preset reference number.

[0017] The controller can also be configured to send information about the battery cells identified as defective to an external device via a communication unit.

[0018] The battery management method according to an embodiment includes: receiving battery data including voltage data of individual battery cells; generating discharge capacity change rate data based on the battery data; smoothing the voltage data and discharge capacity change rate data to obtain voltage smoothed data and discharge capacity smoothed data; and determining that the individual battery cell is defective based on the voltage smoothed data and discharge capacity smoothed data satisfying defect determination conditions.

[0019] Smoothing voltage data and discharge capacity change rate data can include performing exponential smoothing on voltage data and discharge capacity change rate data based on a smoothing coefficient applied to exponential smoothing.

[0020] Smoothing voltage and discharge capacity change rate data can include obtaining predicted values ​​by performing a weighted average of past predicted values ​​and past observations to exponentially smooth the voltage and discharge capacity change rate data.

[0021] Determining that a battery cell is defective can be based on the simultaneous fulfillment of defect determination conditions by voltage smoothing data and discharge capacity smoothing data within a preset time period.

[0022] The battery management method according to the embodiment may further include: determining that the voltage smoothing data and the discharge capacity smoothing data meet the defect determination conditions based on the fact that the voltage smoothing data is less than the average voltage of multiple battery cells for a preset unit time and the discharge capacity smoothing data is greater than the discharge capacity change rate of multiple battery cells for that unit time.

[0023] The battery management method according to the embodiment may further include: determining that the voltage smoothing data and the discharge capacity smoothing data meet the defect determination conditions based on the number of times the voltage smoothing data is less than the average voltage and the number of times the discharge capacity smoothing data exceeds the discharge capacity change rate within a certain period of time being greater than or equal to a preset reference number.

[0024] The battery management method according to the embodiment may further include sending information about a battery cell identified as defective to an external device via a communication unit.

[0025] Beneficial effects

[0026] Using the battery management device according to the embodiment, the efficiency of detecting battery cells with assembly defects can be improved by using smoothed data, and the fire risk during battery use can be minimized by detecting battery cells with assembly defects at an early stage. Attached Figure Description

[0027] Figure 1 This is a block diagram illustrating the configuration of a general battery system including a battery management device according to an embodiment.

[0028] Figure 2 This is a block diagram illustrating the configuration of a battery management device according to an embodiment.

[0029] Figure 3 The process of determining whether a battery is defective is illustrated schematically by a battery management device according to an embodiment.

[0030] Figure 4A shows the raw data of the discharge capacity change rate used in the battery management device according to the embodiment.

[0031] Figure 4B shows the raw data of the voltage used in the battery management device according to an embodiment.

[0032] Figure 5A shows smoothed data of the rate of change of discharge capacity used in the battery management device according to an embodiment.

[0033] Figure 5B shows smoothed data of the voltage used in the battery management device according to an embodiment.

[0034] Figure 6 The defect determination conditions used in the battery management device according to the embodiment are shown.

[0035] Figure 7 This is a control flowchart of a battery management method according to an embodiment. Detailed Implementation

[0036] In the following, various embodiments disclosed herein will be described in detail with reference to the accompanying drawings. In this document, the same reference numerals will be used for the same parts in the drawings, and the same parts will not be described redundantly.

[0037] The various embodiments disclosed herein are illustrated only for the purpose of describing embodiments, and the various embodiments disclosed herein may be implemented in various forms and should not be construed as limited to the embodiments described herein.

[0038] As used in various embodiments, the terms "first," "second," "first," "second," etc., may modify various components regardless of their importance and do not limit the components. For example, a first component may be named a second component without departing from the claims of the embodiments disclosed herein, and similarly, a second component may be named a first component.

[0039] The terminology used herein is used only to describe certain exemplary embodiments and may not be intended to limit the scope of other exemplary embodiments. It should be understood that, unless the context clearly specifies otherwise, the singular form includes plural references.

[0040] All terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed herein pertain. It will be further understood that terms such as those defined in common dictionaries should be interpreted as having the same or similar meaning as they have in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly stated herein. In some cases, terms defined herein may be interpreted as excluding the embodiments disclosed herein.

[0041] Figure 1 This is a block diagram illustrating the configuration of a general battery system including a battery management device according to various embodiments.

[0042] Specifically, Figure 1 A battery system 10 and a higher-level controller 20, including a higher-level system, are schematically illustrated according to embodiments disclosed herein.

[0043] like Figure 1 As shown, the battery system 10 may include multiple battery modules 12, sensor units 14, switching units 16, and battery management devices 1. The battery system 10 may include multiple provided battery modules 12, sensor units 14, switching units 16, and battery management devices 1.

[0044] Multiple battery modules 12 may include at least one rechargeable / dischargeable battery cell 13. Battery cell 13 may include a positive electrode, positive electrode material, negative electrode, negative electrode material, separator, polymer, and casing. In this configuration, multiple battery modules 12 may be connected in series or in parallel.

[0045] The sensor unit 14 may include a voltage sensor 2, a current sensor 3, and a temperature sensor (not shown).

[0046] Voltage sensor 2 can be connected in parallel with the battery and is configured to detect the battery voltage across opposite ends of the battery and generate a voltage signal indicating the detected battery voltage.

[0047] The current sensor 3 can detect the current used in determining the state of charge (SOC) of the battery cell 13.

[0048] The current sensor 3 may include any component for generating a signal corresponding to the magnitude of the charging current, and may be mounted on the charging / discharging path, wherein the charging / discharging current flows in the battery.

[0049] The current sensor 3 can measure the battery current flowing in the battery, i.e., the charging current and the discharging current, and send the measurement results to the battery management device 1. According to an embodiment, the current sensor 3 can measure the battery current at predetermined intervals and send the measurement results to the battery management device 1 during a charging cycle for charging the battery using power from an external device or during a discharging cycle for discharging the battery.

[0050] A temperature sensor can be configured to measure battery temperature and generate a temperature signal indicating the measured battery temperature. The temperature sensor can be disposed within a housing to measure a temperature close to the actual temperature of the battery. For example, the temperature sensor can be attached to the surface of at least one battery cell included in a cell group and detect the surface temperature of the battery cell as the battery temperature.

[0051] A temperature sensor can be configured to measure the external temperature as the temperature at a predetermined location spaced apart from the battery, and generate a temperature signal indicating the measured external temperature. The temperature sensor can be positioned at a predetermined location outside the housing, where heat exchange occurs between the battery and the atmosphere. According to an embodiment, the temperature sensor can be implemented as a combination of one, two, or more known temperature sensing elements (such as thermocouples, thermistors, bimetallic sensors, etc.). A current sensor can detect the current flowing in the battery system 10. In this case, a detection signal can be sent to the battery management device 1.

[0052] Although Figure 1 The sensor unit 14 is connected between the positive terminal of the battery cell 13 and the switching unit 16, but Figure 1 The connection relationships between the components shown are examples and are not limited to these.

[0053] The switching unit 16 can be connected in series to the positive (+) terminal side or the negative (-) terminal side of the battery module 12 to control the charging / discharging current of the battery module 12. For example, for the switching unit 16, depending on the specifications of the battery system 10, at least one relay, magnetic contactor, etc. can be used.

[0054] The battery management device 1 can perform control and management by monitoring the voltage, current, temperature, etc. of the battery system 10 to prevent overcharging and over-discharging, and may include, for example, a battery management system (BMS).

[0055] The battery management device 1, which serves as an interface for receiving measured values ​​of the various parameters mentioned above, may include multiple terminals and circuitry connected thereto for processing input values. Furthermore, the battery management device 1 can control the switching unit 16, such as a relay or contactor, to turn on / off, and can be connected to the battery modules 12 to monitor the status of each battery module 12.

[0056] The battery management device 1 can receive temperature data, voltage data and current data from the sensor unit 14 to obtain battery status information and diagnose the battery status.

[0057] The upper-level controller 20 can send control signals for controlling the battery module 12 to the battery management device 1. Therefore, the battery management device 1 can be controlled in its operation based on the control signals applied from the upper-level controller 20. Furthermore, the battery module 12 can be a component included in an energy storage system (ESS). In this case, the upper-level controller 20 can be a battery bank control unit (BBMS) including multiple battery systems 10 or an ESS control unit for controlling the entire ESS including multiple banks. However, the battery system 10 is not limited to such purposes.

[0058] Figure 2This is a block diagram illustrating the configuration of a battery management device according to an embodiment.

[0059] refer to Figure 2 According to the embodiment, the battery management device 1 may include a control unit 100 including at least one processor 110 and a memory 120, and a communication unit 200, and can diagnose the battery by communicating with an external device 4 via the communication unit 200.

[0060] According to an embodiment, the external device 4 communicating with the battery management device 1 may include a user terminal that sends diagnostic results from the battery management device 1.

[0061] Specifically, when the external device 4 is a user terminal, the control unit 100 of the battery management device 1 can send the battery diagnostic results to the user terminal so that the user can check the diagnostic results. In this case, the user terminal may include, but is not limited to, a personal computer (PC), a terminal, a portable telephone, a smartphone, a handheld device, a wearable device, etc.

[0062] When external device 4 is a server device, the server device can be implemented using various computing devices such as workstations, clouds, data drives, data stations, etc. A server device can be implemented as one or more server devices that are physically or logically separated based on their functions, detailed configurations, data, etc., and can send and receive data through communication between server devices, and can process the sent and received data.

[0063] The battery management device 1 according to the embodiment can refer to any electronic device including processor 110 and memory 120, and can be installed in a vehicle for operation. Each component of the battery management device 1 will be described in detail below.

[0064] The communication unit 200 may include a wireless communication unit 210 and a wired communication unit 220 for communicating with the external device 4. The communication unit 200 may send and receive programs or various data, such as those for characteristic calculations, classification, and lifetime estimation of battery cells, to and from a separately provided external server.

[0065] The wireless communication unit 210 may include at least one of a short-range communication module or a long-range communication module.

[0066] The short-range communication module can communicate with an external device 4 adjacent to the battery management device 1 using a short-range communication method. In this document, the short-range communication module can use one of the following communication methods: Bluetooth, Bluetooth Low Energy (BLE), Infrared Data Association (IrDA), Zigbee, WiFi, WiFi Direct, Ultra-Wideband (UWB), or Near Field Communication (NFC).

[0067] The long-range wireless communication module may include communication modules that perform various types of long-range communication, and may include a mobile communication module. The mobile communication unit can transmit and receive radio signals from at least one of a base station, an external terminal, or an external device 4 via a mobile communication network. The long-range communication module can communicate with the external device 4 or other electronic devices via a nearby access point (AP). The AP can connect the local area network (LAN) to which the battery management device 1 is connected to to the wide area network (WAN) to which the communication server is connected. Therefore, the battery management device 1 can communicate with each other via the external device 4 and the WAN connected to the communication server.

[0068] The wired communication unit 220 can access a wired communication network and communicate with the external device 4 through the wired communication network. For example, the wired communication unit 220 can access the wired communication network via Ethernet (IEEE 802.3, technical standard), access the wired communication network via CAN communication, and send data to and receive data from the external device 4 through the wired communication network.

[0069] The battery management device 1 according to an embodiment may include an input / output interface (not shown). An interface may be provided to allow data to be sent and received via connection to an input device (not shown) such as a keyboard, mouse, touch panel, etc., an output device such as a display (not shown), and a processor 110.

[0070] The memory 120 can store various information required by the battery management device 1. Specifically, the memory 120 can store the operating system and programs required by the battery management device 1, or store the data required by the battery management device 1.

[0071] Specifically, the memory 120 can store various programs related to the characteristic calculation, classification, and lifespan estimation of individual battery cells. Furthermore, the memory 120 can store various data for each individual battery cell, such as voltage, current, and characteristic data.

[0072] The memory 120 can also store the defect determination conditions of the battery cell 13 used by the processor 110.

[0073] The memory 120 may include volatile memory 120, such as static random access memory (S-RAM) and dynamic random access memory (D-RAM), for temporary data storage. The memory 120 may also include non-volatile memory 120, such as read-only memory (ROM), erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM), for long-term data storage.

[0074] The processor 110 can control the battery management device 1 as a whole by outputting control signals. The processor 110 may include one CPU or graphics processing unit (GPU) or multiple CPUs or GPUs. In this case, the processor 110 may be implemented as an array of multiple logic gates, or it may be implemented as a combination of a general-purpose microprocessor 110 and a memory 120 storing a program executable on the microprocessor 110.

[0075] The memory 120 and processor 110 may be included in a control unit 100, which controls the aforementioned components to determine whether a defect has occurred in the battery cell.

[0076] The control unit 100 can generate discharge capacity change rate data based on battery data, and smooth the voltage data and discharge capacity change rate data to obtain smoothed voltage data and smoothed discharge capacity data. The control unit 100 can perform exponential smoothing on the voltage data and discharge capacity change rate data based on a smoothing coefficient applied to exponential smoothing.

[0077] Specifically, the control unit 100 can obtain the predicted value by performing a weighted average of past predicted values ​​and past observed values ​​to exponentially smooth the voltage data and discharge capacity change rate data.

[0078] The control unit 100 can determine that a battery cell is defective based on the fact that the voltage smoothing data and discharge capacity smoothing data meet the defect determination conditions, and send the information of the battery cell determined to be defective to the external device 4 through the communication unit 200.

[0079] The control unit 100 can determine a battery cell as defective based on both voltage smoothing data and discharge capacity smoothing data meeting a predetermined defect determination condition within a preset time period. Therefore, the control unit 100 can determine whether a battery cell is defective based on two conditions, thereby reducing false diagnoses and providing accurate diagnoses.

[0080] Regarding the defect determination criteria for individual battery cells, when the voltage smoothing data is less than the average voltage of multiple battery cells over a preset unit time and the discharge capacity smoothing data is greater than the rate of change of discharge capacity of multiple battery cells over that unit time, the control unit 100 can determine that the defect determination criteria are met.

[0081] The control unit 100 can determine whether the defect determination condition is met based on the number of times the voltage smoothing data is less than the average voltage and the number of times the discharge capacity smoothing data exceeds the discharge capacity change rate within a certain time period being greater than or equal to a preset reference number.

[0082] In this way, the battery management device 1 according to the embodiment can smooth the raw battery data and diagnose whether a defect has occurred in a battery cell by using both voltage smoothing data and discharge capacity smoothing data, thereby significantly improving the reliability of the diagnosis.

[0083] Figure 3 The process of determining whether a battery is defective is illustrated schematically by a battery management device according to an embodiment. Figure 3 Components 101 to 103 can be implemented as software blocks and can be stored in memory 120 and executed by processor 110.

[0084] The control unit 100 can receive battery data from individual battery cells from the sensor unit, specifically voltage data from voltage sensor 2 and current data from current sensor 3.

[0085] The discharge capacity data generation unit 101 of the control unit 100 can generate discharge capacity data by integrating current-voltage data. That is, the control unit 100 can integrate current-voltage data to obtain the area of ​​the discharge curve indicating voltage versus time at a specific current, and generate discharge capacity data having the area of ​​the discharge curve.

[0086] The control unit 100 can generate discharge capacity change rate data as the rate of change of discharge capacity data, and can generate discharge capacity change rate data as the difference from the previous data point by using discharge capacity data points based on each time interval.

[0087] For example, for two consecutive data points (t) i C i ) and (t i+1 C i+1 The rate of change of discharge capacity R can be calculated using the equation provided below.

[0088] [Equation 1]

[0089]

[0090] In this article, C i and C i+1 This can be interpreted as the discharge capacity relative to two consecutive time intervals, and t1 and t2. i+1 It can mean C i and C i+1 The measurement time.

[0091] Subsequently, the exponential smoothing execution unit 102 of the control unit 100 can perform exponential smoothing on the received voltage data and discharge capacity change rate data, wherein exponential smoothing can smooth the time series battery data to remove trends or seasonality and reduce noise.

[0092] The control unit 100 can smooth the voltage and discharge capacity data based on simple exponential smoothing or double exponential smoothing, but there are no restrictions on the method, as long as the method can smooth the data.

[0093] When the smoothed voltage data and discharge capacity data meet specific conditions, the defect determination unit 103 of the control unit 100 can determine that the battery cell is defective.

[0094] In other words, when both the voltage smoothing data and the discharge capacity smoothing data satisfy the defect determination condition, the control unit 100 can determine that the battery cell is defective. In this case, when either the voltage smoothing data or the discharge capacity smoothing data satisfies the defect determination condition, the control unit 100 can determine that the battery cell is normal to prevent false diagnosis.

[0095] Subsequently, the control unit 100 can send information about the battery cells identified as defective or normal to the external device 4, and the battery user or manager can remotely determine whether the battery cells are defective through the external device 4.

[0096] Figure 4A shows raw data of the discharge capacity change rate used in the battery management device according to an embodiment, and Figure 4B shows raw data of the voltage used in the battery management device according to an embodiment.

[0097] Referring to Figure 4A, the control unit 100 can obtain discharge capacity change rate data based on battery data, wherein the discharge capacity change rate data can be shown as a discharge capacity change rate curve as shown in Figure 4A.

[0098] Referring to Figure 4B, the control unit 100 can obtain voltage data included in the battery data, wherein the voltage data can be displayed as a voltage curve as shown in Figure 4B.

[0099] As shown in Figures 4A and 4B, raw data without exponential smoothing has sporadic profiles, making it difficult to select the appropriate specifications for defect selection when using raw data to determine whether a battery is defective, as is the case in conventional techniques.

[0100] Therefore, when determining whether a battery is defective by using raw data as in conventional technologies, the defect detection capability may be reduced, making it impossible to detect battery defects and thus leading to battery fires and accidents.

[0101] Specifically, in Figure 4A, the original data was not smoothed, causing the fluctuation range (a) of the discharge capacity change rate curve to be close to 6. Similarly, in Figure 4B, due to the original data, the fluctuation range (a) of the voltage curve is close to 150 at 150 seconds.

[0102] Therefore, raw data has a wider range of fluctuations and more noise than smoothed data, thus distorting the actual data and reducing the accuracy of analyses used to detect battery defects.

[0103] On the other hand, the battery management device 1 according to the embodiment can reduce fluctuations in battery data and minimize instability of battery data through smoothing. In this way, false detection of battery performance degradation can be prevented, and errors in battery defect diagnosis can be minimized.

[0104] Figure 5A shows smoothed data of the discharge capacity change rate used in the battery management device according to the embodiment, and Figure 5B shows smoothed data of the voltage used in the battery management device according to the embodiment.

[0105] Referring to Figure 5A, the control unit 100 can obtain discharge capacity smoothed data by performing exponential smoothing on the discharge capacity change rate data, wherein the discharge capacity smoothed data can be shown as a discharge capacity change rate curve as shown in Figure 5A.

[0106] Referring to Figure 5B, the control unit 100 can obtain voltage smoothed data by performing exponential smoothing on the voltage data, wherein the voltage smoothed data can be shown as a voltage curve as shown in Figure 5B.

[0107] As shown in Figures 5A and 5B, the smoothed data has a gently sloping curve, which makes it easier to select specifications for battery defects and can improve detection capabilities.

[0108] Therefore, similar to the battery management device 1 according to the embodiment, when determining whether a battery is defective by using smoothing data, the defect detection capability can be improved, and thus the associated battery fires and accidents can be prevented.

[0109] Specifically, in Figure 5A, the data is smoothed discharge capacity data, and therefore the fluctuation range (a) of the discharge capacity change rate curve is 0.8, which shows that the fluctuation range is reduced compared to the original data. Similarly, in Figure 5B, due to the smoothed voltage data, it can be seen that the fluctuation range (a) of the voltage curve decreases to 40 at 150 seconds.

[0110] In this way, smoothed data has a narrower range of fluctuations than the original data, and exhibits changes that are easier to observe over time with less noise, thereby improving the accuracy of interpretation for battery defect detection.

[0111] In the following, a defect determination condition according to an embodiment for determining whether a battery cell is defective based on smoothed data by the battery management device 1 will be described.

[0112] Figure 6 The defect determination conditions used in the battery management device according to the embodiment are shown.

[0113] refer to Figure 6 The control unit 100 can determine whether the voltage smoothing data and discharge capacity smoothing data satisfy at least one of the following defect determination conditions: unit time determination condition (a); minimum determination condition (b); maximum determination condition (c); and count determination condition (d).

[0114] Furthermore, the control unit 100 can determine whether each of the voltage smoothing data and the discharge capacity smoothing data satisfies any one of the defect determination conditions, and when each of the voltage smoothing data and the discharge capacity smoothing data satisfies any one of the defect determination conditions, the control unit 100 can determine that the battery cell is defective.

[0115] In other words, when the discharge capacity smoothing data does not meet any of the defect determination conditions but the voltage smoothing data meets at least one of the defect determination conditions, the control unit 100 can determine that no battery defect has occurred.

[0116] In this way, the battery management device 1 according to the embodiment can strictly and accurately determine whether the battery is defective.

[0117] Specifically, the control unit 100 can set the entire defined time period, for example, a defined time period from 0 to 300 seconds.

[0118] Subsequently, for voltage-related unit-time determination condition (a), when the average voltage of the battery cells included in a battery tray is less than -45mV during the determination period, the control unit 100 can determine that the battery meets the defect determination condition.

[0119] For the unit time determination condition (a) related to the rate of change of discharge capacity, when the average rate of change of discharge capacity of the battery cells included in a battery tray is at least 0.4 during the determination period, the control unit 100 can determine that the battery meets the defect determination condition.

[0120] For the minimum determination condition (b) and the maximum determination condition (c) related to voltage, the control unit 100 can determine whether a defect has occurred by performing defect determination on the voltage smoothing data within a range from a minimum of 221 seconds to a maximum of 280 seconds.

[0121] For the minimum determination condition (b) and the maximum determination condition (c) related to the rate of change of discharge capacity, the control unit 100 can determine whether a defect has occurred by performing defect determination on the voltage smoothing data in the range of a minimum of 221 seconds to a maximum of 280 seconds.

[0122] In other words, the battery management device 1 according to the embodiment can set the optimal determination range for determining whether the battery is defective by limiting the minimum determination condition (b) and the maximum determination condition (c) that can be set experimentally.

[0123] For voltage-related counting determination condition (d), the control unit 100 can count the number of times that voltage smoothing data is determined to be defective during a defined time period, and the number of counts is at least 59.

[0124] For the counting determination condition (d) related to the discharge capacity change rate, the control unit 100 can count the number of times that the discharge capacity smoothing data is determined to be defective during a defined time period, and the number of counts is at least 65.

[0125] In other words, when the voltage smoothing data satisfies at least one of the unit time determination condition (a), minimum determination condition (b), maximum determination condition (c), and count determination condition (d), and the discharge capacity smoothing data simultaneously satisfies at least one of the unit time determination condition (a), minimum determination condition (b), maximum determination condition (c), and count determination condition (d), the control unit 100 can determine that the battery is defective.

[0126] Figure 7 This is a control flowchart of a battery management method according to an embodiment.

[0127] refer to Figure 7 In operation 700, the control unit 100 can receive battery data from multiple individual battery cells. The battery data received by the control unit 100 can be for each individual battery cell or for each battery module.

[0128] In operation 710, the control unit 100 can generate voltage data and discharge capacity change rate data based on battery data. Voltage data can refer to data obtained by extracting voltage values ​​from battery data and arranging the voltage values ​​in a time series, and discharge capacity change rate data can refer to discharge capacity change rate data calculated based on current data and voltage data.

[0129] In operation 720, control unit 100 can perform exponential smoothing by applying exponential smoothing logic to the raw data of voltage data and discharge capacity change rate. Therefore, control unit 100 can improve defective battery detection capability by smoothing the raw data.

[0130] Subsequently, in operation 730, the control unit 100 can determine whether the number of times a defect in which the voltage smoothing data is less than the average voltage of multiple battery cells is determined exceeds a reference number.

[0131] When it is determined that the number of times a defect in which the voltage smoothing data is less than the average voltage of multiple battery cells is determined exceeds a reference number (yes in operation 730), in operation 740, the control unit 100 may determine whether the number of times a defect in which the discharge capacity smoothing data is less than the average discharge capacity change rate is determined exceeds a reference number.

[0132] When the number of times a defect is identified where the discharge capacity smoothing data is less than the average discharge capacity change rate exceeds the reference number (yes in operation 740), in operation 750, the control unit 100 can determine that the battery cell is defective.

[0133] At this point, the order in which defects are determined for voltage smoothing data and discharge capacity smoothing data are performed is not restricted, and unlike the above, defects for discharge capacity smoothing data can be determined first.

[0134] Therefore, the battery management device 1 according to the embodiment can use voltage smoothing data and discharge capacity smoothing data obtained by smoothing the original data to more accurately diagnose battery defects.

[0135] Furthermore, the disclosed embodiments can be implemented in the form of a recording medium storing computer-executable instructions. The instructions can be stored as program code, and when executed by a processor, a program module can be generated and operations according to the disclosed embodiments can be performed. The recording medium can be implemented as a computer-readable recording medium.

[0136] Computer-readable recording media can include any type of recording medium that stores instructions that can be interpreted by a computer. For example, computer-readable recording media can include ROM, RAM, magnetic tape, magnetic disk, flash memory, optical data storage devices, etc.

[0137] Furthermore, computer-readable recording media may be provided in the form of non-transitory storage media. In this document, the term "non-transitory storage media" simply means that the storage medium is a tangible device and does not include signals (e.g., electromagnetic waves), but this term does not distinguish between cases where data is stored semi-permanently in the storage medium and cases where data is temporarily stored in the storage medium. For example, "non-transitory storage media" may include buffers for temporarily storing data.

[0138] According to embodiments, methods according to various embodiments disclosed herein may be included and provided in a computer program product. The computer program product can be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable recording medium (e.g., an optical disc read-only memory (CD-ROM)) or via an app store (e.g., the Play Store). TM Online distribution (e.g., download or upload) or direct distribution between two user devices (e.g., smartphones). When distributed online, at least a portion of the computer program product (e.g., a downloadable app) may be temporarily generated or at least temporarily stored in a machine-readable recording medium, such as the memory of a manufacturer's server, an app store's server, or the memory of a relay server 102.

[0139] Even though all components constituting the embodiments disclosed herein have been described above as operating in one or more combinations, the embodiments disclosed herein are not necessarily limited to these embodiments. That is, within the scope of the objectives of the embodiments disclosed herein, all components can be operated by selectively combining them into one or more.

[0140] Furthermore, unless otherwise stated, terms such as “comprising,” “constituting,” or “having” above may mean that the corresponding component may be inherent, and therefore should be interpreted as including other components rather than excluding them. Unless otherwise defined, all terms including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed herein pertain. Terms used in the same manner as defined in a dictionary should be interpreted as having the same meaning as in the context of the relevant art, and should not be interpreted as having an ideal or overly formal meaning unless they are explicitly defined in this document.

[0141] The above description is merely an illustration of the technical ideas disclosed herein, and various modifications and variations will be possible for those skilled in the art to which the embodiments disclosed herein pertain without departing from the basic characteristics of the embodiments disclosed herein. Therefore, the embodiments disclosed herein are intended to describe, 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 appended claims, and all technical spirit within the same scope should be understood to be included within the scope of this document.

Claims

1. A battery management device, comprising: A communication unit configured to receive battery data including voltage data of individual battery cells; as well as The control unit is configured to generate discharge capacity change rate data based on the battery data, smooth the voltage data and the discharge capacity change rate data to obtain voltage smoothed data and discharge capacity smoothed data, and determine that the battery cell is defective based on the voltage smoothed data and the discharge capacity smoothed data satisfying the defect determination conditions.

2. The battery management device according to claim 1, wherein, The controller is also configured to perform exponential smoothing on the voltage data and the discharge capacity change rate data based on a smoothing coefficient applied to exponential smoothing.

3. The battery management device according to claim 2, wherein, The controller is also configured to obtain predicted values ​​by performing a weighted average of past predicted values ​​and past observed values ​​to exponentially smooth the voltage data and the discharge capacity change rate data.

4. The battery management device according to claim 1, wherein, The controller is also configured to determine that the battery cell is defective based on the simultaneous fulfillment of the defect determination conditions by the voltage smoothing data and the discharge capacity smoothing data within a preset time period.

5. The battery management device according to claim 4, wherein, The controller is further configured to determine that the voltage smoothing data and the discharge capacity smoothing data satisfy the defect determination condition based on the voltage smoothing data being less than the average voltage of multiple battery cells over a preset unit time and the discharge capacity smoothing data being greater than the rate of change of discharge capacity of the multiple battery cells over the unit time.

6. The battery management device according to claim 5, wherein, The controller is further configured to determine that the voltage smoothing data and the discharge capacity smoothing data meet the defect determination condition based on the number of times the voltage smoothing data is less than the average voltage and the number of times the discharge capacity smoothing data exceeds the discharge capacity change rate during the defined time period being greater than or equal to a preset reference number.

7. The battery management device according to claim 1, wherein, The controller is also configured to send information about the battery cell identified as defective to an external device via the communication unit.

8. A battery management method, comprising: Receive battery data, including voltage data of individual battery cells; Based on the battery data, discharge capacity change rate data is generated; The voltage data and the discharge capacity change rate data are smoothed to obtain smoothed voltage data and smoothed discharge capacity data. as well as The battery cell is determined to be defective based on the fact that the voltage smoothing data and the discharge capacity smoothing data meet the defect determination criteria.

9. The battery management method according to claim 8, wherein, Smoothing the voltage data and the discharge capacity change rate data includes performing exponential smoothing on the voltage data and the discharge capacity change rate data based on a smoothing coefficient applied to exponential smoothing.

10. The battery management method according to claim 9, wherein, Smoothing the voltage data and the discharge capacity change rate data includes obtaining a predicted value by performing a weighted average of past predicted values ​​and past observed values ​​to exponentially smooth the voltage data and the discharge capacity change rate data.

11. The battery management method according to claim 8, wherein, Determining that a battery cell is defective includes determining that the battery cell is defective based on the simultaneous fulfillment of the defect determination conditions by the voltage smoothing data and the discharge capacity smoothing data within a preset predetermined time period.

12. The battery management method according to claim 11, further comprising: Based on the fact that the voltage smoothing data is less than the average voltage of multiple battery cells over a preset unit time and the discharge capacity smoothing data is greater than the rate of change of discharge capacity of the multiple battery cells over the unit time, it is determined that the voltage smoothing data and the discharge capacity smoothing data satisfy the defect determination condition.

13. The battery management method according to claim 12, further comprising: Based on the number of times the voltage smoothing data is less than the average voltage and the number of times the discharge capacity smoothing data exceeds the discharge capacity change rate during the defined time period being greater than or equal to a preset reference number, it is determined that the voltage smoothing data and the discharge capacity smoothing data meet the defect determination condition.

14. The battery management method of claim 8 further includes transmitting information about the battery cell identified as defective to an external device via a communication unit.

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